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NBME 21

Block 1/Question#1
A 24-year-old woman with sickle cell disease comes to the ...
Serum parvovirus B19 IgM antibody test

Block 1/Question#2
A 6-month-old girl is brought to the physician because her ...
GM2

Block 1/Question#3
An investigator is studying the efficacy of distinct vaccine ...
Flagellin

Block 1/Question#4
A 67-year-old man comes to the emergency department because ...
Translation

Block 1/Question#5
A 45-year-old woman is brought to the emergency department 45 ...
Absorption atelectasis

Block 1/Question#6
A normal-appearing 17-year-old girl has never had a menstrual ...
Androgen insensitivity syndrome

Block 1/Question#7
A 30-year-old primigravid woman at 22 weeks' gestation comes ...
Listeria monocytogenes

Block 1/Question#8
A 52-year-old woman is admitted to the hospital because of ...
Speak with the two gynecologists to attempt to coordinate care

Block 1/Question#9
A 53-year-old woman who underwent an operation for breast ...
Breast: antagonist; Uterus: partial agonist

Block 1/Question#10
A 34-year-old woman is brought to the emergency department 30 ...
Primary metabolic acidosis with increased anion gap

Block 1/Question#11
A 27-year-old primigravid woman at 34 weeks' gestation is ...
Schistocytes

Block 1/Question#12
A 25-year-old nulligravid woman comes to the physician ...
Endometrial hyperplasia

Block 1/Question#13
A 25-year-old man develops shortness of breath after moving ...
Decreased alveolar Po2

Block 1/Question#14
A 21-year-old man is brought to the emergency department 45 ...
Streptococcus pneumoniae

Block 1/Question#15
A 35-year-old man comes to the physician because of a 1-day ...
Increased vascular permeability

Block 1/Question#16
A 43-year-old man comes to the physician for a follow-up ...
Aortic

Block 1/Question#17
A 7-year-old girl is brought to a clinic in a developing ...
Methionine

Block 1/Question#18
A 61-year-old woman is brought to the physician by her ...
Donepezil

Block 1/Question#19
A 22-year-old man has had frequent episodes of cutaneous ...
C1 esterase inhibitor (binds activated C1r, C1s)

Block 1/Question#20
A 10-year-old girl develops fever, malaise, and loss of ...
Retrograde transport through nerves

Block 1/Question#21
A 40-year-old man with type 2 diabetes mellitus comes to the ...
Stimulation of the peroxisome proliferator-activated receptor γ

Block 1/Question#22
A 36-year-old man with AIDS elects to participate in a ...
Chemokine

Block 1/Question#23
A 59-year-old man comes to the physician because of a 3-month ...
Foci of keratinization

Block 1/Question#24
A 23-year-old man drinks alcohol heavily on a weekend. Which ...
Fatty change

Block 1/Question#25
A 28-year-old man is brought to the emergency department 30 ...
Dissecting aneurysm

Block 1/Question#26
A 62-year-old man who is a farmer comes to the physician ...
Actinic keratosis

Block 1/Question#27
A 60-year-old man is brought to the emergency department ...
Urethral disruption

Block 1/Question#28
A 47-year-old man is brought to the emergency department by ...
Mixed venous oxygen tension

Block 1/Question#29
A 34-year-old man comes to the physician because of a 2-week ...
Cluster headache

Block 1/Question#30
A newborn has female external genitalia and a 46,XY ...
Dihydrotestosterone

Block 1/Question#31
A 30-year-old woman comes to the office for a follow-up ...
Linoleic acid

Block 1/Question#32
A 50-year-old man has had progressive dyspnea on exertion ...
Usual interstitial pneumonitis

Block 1/Question#33
A 30-year-old man comes to the physician because of a ...
Varicella-zoster virus infection

Block 1/Question#34
A 30-year-old man develops urinary incontinence 2 weeks after ...
Pelvic nerves

Block 1/Question#35
A 7-year-old boy is brought to the physician by his mother ...
Increased blood lead

Block 1/Question#36
A 51-year-old woman comes to the physician because of a ...
Area labeled 'B' (Parietal cell)

Block 1/Question#37
A 35-year-old man with diabetic ketoacidosis has a decrease ...
Serum potassium concentration

Block 1/Question#38
A 47-year-old woman with aplastic anemia is being treated for ...
Amphotericin B

Block 1/Question#39
A 33-year-old woman comes to the physician because of fever, ...
Genital herpes

Block 1/Question#40
A physician prescribes a recently marketed drug for 20 ...
Phase 4

Block 1/Question#41
A 35-year-old woman comes to the physician because of a 2-day ...
Uroporphyrinogen decarboxylase

Block 1/Question#42
A 36-year-old woman undergoes a total hysterectomy and ...
Hyperplasia

Block 1/Question#43
A 52-year-old man is brought to the emergency department 30 ...
Histamine

Block 1/Question#44
A test has been developed to screen for human papillomavirus ...
Predictive value of a positive test

Block 1/Question#45
An 18-year-old man comes to the physician because of a 2-week ...
Pyruvate kinase

Block 1/Question#46
A 66-year-old man is brought to the emergency department ...
Lipopolysaccharide stimulation of toll-like receptor

Block 1/Question#47
A 26-year-old woman (III-2) comes to the physician for ...
50% in females but near 0 in males

Block 1/Question#48
A 44-year-old man is admitted to the hospital because of ...
Increasing cGMP

Block 1/Question#49
An 80-year-old woman comes to the emergency department ...
Hydrochlorothiazide

Block 1/Question#50
A photograph is shown of a myelin-stained cross section of a ...
Loss of sensation to vibration over both feet

Block 2/Question#1
A 27-year-old man comes to the physician for an examination ...
Schizoid

Block 2/Question#2
A 4-year-old girl is conscious but unable to breathe ...
Pseudocholinesterase deficiency

Block 2/Question#3
A 17-year-old boy returns to the locker room after football ...
Apocrine

Block 2/Question#4
An 18-year-old woman comes to the office because of a 2-week ...
Extensor carpi radialis brevis

Block 2/Question#5
A 2-week-old male newborn has a patent ductus arteriosus. ...
Higher than normal left ventricular cardiac output

Block 2/Question#6
A 38-year-old woman comes to the physician because of a ...
Serum calcium concentration

Block 2/Question#7
A 50-year-old man with rheumatoid arthritis comes to the ...
Anemia of chronic disease

Block 2/Question#8
A 55-year-old man is diagnosed with renal artery stenosis. ...
Cortex

Block 2/Question#9
A 40-year-old man is brought to the emergency department 45 ...
Metabolic acidosis and respiratory acidosis

Block 2/Question#10
A 42-year-old woman comes to the physician because of a ...
Rosacea

Block 2/Question#11
A 22-year-old woman, gravida 1, para 1, is brought to the ...
Internal iliac

Block 2/Question#12
A 66-year-old woman comes to the physician because of fever, ...
Diverticulitis

Block 2/Question#13
A 53-year-old woman with gastroesophageal reflux disease ...
Omeprazole

Block 2/Question#14
A 30-year-old woman comes to the office because she is ...
Abnormal brain development

Block 2/Question#15
A 48-year-old man is brought to the emergency department ...
Splenic and left renal

Block 2/Question#16
A 34-year-old woman comes to the physician because of a ...
Atrioventricular bundle

Block 2/Question#17
Scientists have identified the flawed gene that causes about ...
Mismatch repair

Block 2/Question#18
A 34-year-old woman comes to the physician because she has ...
“I’m concerned about how bad you’ve been feeling lately. Have you had any thoughts about death or wanting to be dead?”

Block 2/Question#19
A 3-year-old boy who recently immigrated to the USA is ...
Increased proportions of osteoid

Block 2/Question#20
A 14-year-old girl is brought to the physician by her mother ...
Trichotillomania

Block 2/Question#21
A 35-year-old woman undergoes flexible nasopharyngoscopy ...
Superior to the superior concha

Block 2/Question#22
A 33-year-old woman, gravida 4, para 4, is admitted to the ...
Transfusion-related acute lung injury

Block 2/Question#23
A 4-year-old boy with chronic granulomatous disease is ...
Macrophages producing interleukin-1 (IL-1)

Block 2/Question#24
A 65-year-old man dies in a motor vehicle collision. A ...
Squamous cell carcinoma

Block 2/Question#25
A 54-year-old man comes to the physician for a routine health ...
Area labeled 'F' (Efferent arteriole)

Block 2/Question#26
A healthy 32-year-old woman at 35 weeks' gestation is ...
Birth canal reflex

Block 2/Question#27
A 47-year-old woman with psoriasis comes to the physician for ...
“Most people find it difficult to stick to a routine. How did you do?”

Block 2/Question#28
A 64-year-old woman with type 2 diabetes mellitus and ...
Gemfibrozil

Block 2/Question#29
A healthy 25-year-old man is participating in a study of ...
Alanine

Block 2/Question#30
A 44-year-old man comes to the physician because of ...
Leukotriene C4: increased;
Arachidonic acid: increased;
Prostaglandin H2: decreased;
Prostaglandin E2: decreased


Block 2/Question#31
A 37-year-old man is brought to the emergency department 45 ...
Intercostal

Block 2/Question#32
A 17-year-old boy has the acute onset of lethargy, sore ...
Lymphocytes

Block 2/Question#33
A 68-year-old man comes to the physician because of a 1-month ...
Libido: normal; Nocturnal erections: normal

Block 2/Question#34
A 28-year-old man is brought to the emergency department ...
Inferior rectus and inferior oblique

Block 2/Question#35
A 4-month-old female infant is brought to the emergency ...
Hyponatremia

Block 2/Question#36
An investigator is conducting a study of antiretroviral ...
Enfuvirtide

Block 2/Question#37
A 17-year-old boy is evaluated for constitutional delay in ...
Craniopharyngioma

Block 2/Question#38
A 63-year-old man with bladder cancer starts treatment with ...
Tubulin polymerization stabilization

Block 2/Question#39
A 64-year-old man with bronchospastic pulmonary disease ...
Enhanced action of the agonist at β-adrenergic receptors

Block 2/Question#40
Acetaminophen and nonsteroidal antiinflammatory agents reduce ...
Prostaglandin E2

Block 2/Question#41
A 75-year-old woman has the sudden onset of Horner syndrome ...
Posterior inferior cerebellar

Block 2/Question#42
A 26-year-old man with HIV infection comes to the physician ...
Penicillin

Block 2/Question#43
A 78-year-old woman is brought to the emergency department by ...
Embolectomy

Block 2/Question#44
A 75-year-old man has the sudden onset of partial loss of ...
Parietal lobe, left

Block 2/Question#45
A 3-year-old boy is brought to the emergency department ...
Synthesis of factor X (Stuart factor)

Block 2/Question#46
An 8-year-old girl is brought to the physician for a ...
“Your daughter’s development is normal.”

Block 2/Question#47
A 55-year-old woman comes to the physician because of a ...
Increased parathyroid hormone

Block 2/Question#48
A 75-year-old man has fever, back pain, and pain on ...
Enterococcus faecalis

Block 2/Question#49
A 6-year-old girl is brought to the physician by her mother ...
Poxvirus

Block 2/Question#50
A 65-year-old woman comes to the emergency department because ...
Lung and common carotid artery

Block 3/Question#1
A 30-year-old woman develops dimness of vision
Ethambutol

Block 3/Question#2
A 40-year-old man with interstitial pulmonary fibrosis has a ...
Increased radial traction on airways

Block 3/Question#3
A 55-year-old African American man with hypertension is asked ...
Tell the patient that he can change his mind about participating

Block 3/Question#4
A clinical trial is conducted to compare the efficacy of a ...
Surgical procedure group: 400; Medical management group: 400

Block 3/Question#5
A 70-year-old woman is found to have persistent fever despite ...
Candida albicans

Block 3/Question#6
A 40-year-old African American woman comes to the physician ...
1,25-Dihydroxycholecalciferol

Block 3/Question#7
A 65-year-old man comes to the physician because of a 1-month ...
DNA fragmentation

Block 3/Question#8
A 55-year-old woman is brought to the emergency department by ...
Mammillary bodies

Block 3/Question#9
A 75-year-old woman is brought to the emergency department ...
Shrunken eosinophilic (red) neurons

Block 3/Question#10
A 30-year-old man has had intermittent severe lower abdominal ...
Cysteine

Block 3/Question#11
A 50-year-old man is found dead in bed at home. His family ...
Arrhythmia

Block 3/Question#12
A 55-year-old man with hypertension comes to the physician ...
Left renal artery atherosclerosis

Block 3/Question#13
A 40-year-old woman comes to the physician for an initial ...
Antagonizes VLDL-cholesterol secretion

Block 3/Question#14
A 35-year-old man is brought to the emergency department ...
Activation of adenylyl cyclase

Block 3/Question#15
A 47-year-old man has jaundice. Laboratory findings include ...
Obstruction of the bile duct

Block 3/Question#16
A 16-year-old boy is brought to the physician because of a ...
Exercise-induced asthma

Block 3/Question#17
A 66-year-old woman with pancreatic cancer comes to the ...
Short gastric

Block 3/Question#18
An 83-year-old man comes to the physician because of a 3-day ...
Bullous pemphigoid antigen

Block 3/Question#19
A 25-year-old woman develops increasing shortness of breath ...
Four-chamber dilation

Block 3/Question#20
A 68-year-old woman has had a fever and shortness of breath ...
Reactive granulocytosis

Block 3/Question#21
A screening program is instituted for detection of vaginal ...
10%

Block 3/Question#22
A 9-year-old boy has mild mental retardation and a 4-year ...
Rhabdomyoma

Block 3/Question#23
A 43-year-old woman dies after a 10-year illness ...
Area labeled ‘C’ (Caudate nucleus)

Block 3/Question#24
Diastolic blood pressures are obtained in two groups of 100 ...
Median of group Y: higher; Mode of group Y: higher

Block 3/Question#25
A 32-year-old woman comes to the physician because her sister ...
Dysplastic nevi

Block 3/Question#26
A 19-year-old woman comes to the office because of a 1-month ...
Descending colon

Block 3/Question#27
A 55-year-old woman with a benign nodule in the left lobe of ...
External carotid

Block 3/Question#28
A 1-year-old girl is admitted to the hospital because of a ...
Disruption of the secondary structure of collagen molecules

Block 3/Question#29
A 34-year-old man is evaluated after becoming light-headed ...
Number of impulses from carotid baroreceptor: decreased;
Sympathetic efferent activity: increased;
Parasympathetic efferent activity: decreased


Block 3/Question#30
A 41-year-old man comes to the physician because of a 6-week ...
Abduction of the upper extremity

Block 3/Question#31
A 28-year-old woman at 18 weeks' gestation has palpitations. ...
Free T4

Block 3/Question#32
A 72-year-old man comes to the physician because of a 2-week ...
Bleomycin

Block 3/Question#33
Left radial arterial and venous blood samples are drawn from ...
HCO3 transported in the plasma

Block 3/Question#34
A 39-year-old woman with rheumatoid arthritis develops ...
Membranous glomerulonephritis

Block 3/Question#35
A 63-year-old woman comes to the physician because of a 5-day ...
Increased resting cardiac output

Block 3/Question#36
Which of the following best explains why the use of an ...
Myeloma cells do not have membrane-bound surface immunoglobulin

Block 3/Question#37
A 5-year-old boy who has homocystinuria improves with ...
The line on the graph labeled ‘B’

Block 3/Question#38
A 28-year-old man develops a temperature of 39.9°C (103.8°F) ...
Granulocyte colony-stimulating factor

Block 3/Question#39
A 74-year-old woman with mild dementia is admitted to the ...
Inability to understand the severity and prognosis of her medical condition

Block 3/Question#40
A 65-year-old woman undergoes surgical repair of an aneurysm ...
Area labeled ‘A’ (Cranial nerve 3)

Block 3/Question#41
A 75-year-old woman comes to the physician's office because ...
Major depressive disorder

Block 3/Question#42
A 27-year-old primigravid woman at 39 weeks' gestation is ...
Shoulder dystocia

Block 3/Question#43
An undernourished 70-year-old man has fever, night sweats, ...
Interferon-γ

Block 3/Question#44
A 23-year-old woman develops persistent sneezing each year in ...
Stabilization of mast cell membranes

Block 3/Question#45
A 28-year-old man comes to the physician for evaluation of ...
Fructose

Block 3/Question#46
A 38-year-old woman comes to the physician because of a ...
Patent foramen ovale

Block 3/Question#47
A 48-year-old man comes to the physician because of ...
Increased intestinal iron absorption

Block 3/Question#48
A 29-year-old woman comes to the physician because of a ...
Baclofen

Block 3/Question#49
The gene that codes for a protein normally found in the ...
Deletion of a hydrophobic amino acid sequence from the N terminus

Block 3/Question#50
A 32-year-old woman comes to the emergency department because ...
Arthropod vector

Block 4/Question#1
A 50-year-old woman has azotemia. Renal ultrasonography shows ...
Uterine cervix

Block 4/Question#2
A 23-year-old woman comes to the student health center ...
Obliterative endarteritis with lymphocytes and plasma cells

Block 4/Question#3
A study was performed that evaluated the relationship between ...
Odds ratio

Block 4/Question#4
The FOXO transcription factor responds to insulin signaling ...
Nuclear/cytoplasmic shuttling: yes;
Serine phosphorylation: yes
Ubiquitin-mediated proteolysis: no


Block 4/Question#5
An 11-year-old boy has had persistent pain in his right knee ...
Lung

Block 4/Question#6
A 55-year-old man comes to the physician because of a 2-month ...
Cortisol

Block 4/Question#7
A 14-year-old boy is brought to the physician by his mother ...
Inhaled glue

Block 4/Question#8
A 70-year-old woman has had recurrent pneumonia, fatigue, and ...
Euthyroid sick syndrome

Block 4/Question#9
A 60-year-old woman with psoriasis comes to the physician ...
Porphyria cutanea tarda

Block 4/Question#10
A 64-year-old man is evaluated for cough, dyspnea, and chest ...
Hyponatremia

Block 4/Question#11
A study is conducted on patients with asthma to compare a new ...
If the treatment really changes the mean asthma score by 0.4, there is an 80% chance that a study of this size will find a p-value < 0.05

Block 4/Question#12
A 24-year-old man with a history of drug abuse has nausea, ...
Heroin

Block 4/Question#13
A 4-month-old boy is diagnosed with a rare autosomal ...
Dilated rough endoplasmic reticulum

Block 4/Question#14
A 25-year-old woman has a 3-week history of bleeding gums ...
Autoantibodies against platelet glycoproteins

Block 4/Question#15
A 5-year-old boy is brought to the physician for a well-child ...
Lack of choroidal pigment deposition in the macula

Block 4/Question#16
A 40-year-old woman who had pneumonia due to Streptococcus ...
Surfactant

Block 4/Question#17
A 48-year old man is referred for evaluation of possible ...
Increase in width

Block 4/Question#18
A previously healthy 4-week-old male newborn is brought to ...
Pyloric stenosis

Block 4/Question#19
A 45-year-old woman comes to the emergency department because ...
Hepatopancreatic ampulla

Block 4/Question#20
A 7-month-old boy is brought to the physician 2 days after ...
46,XY

Block 4/Question#21
A 47-year-old man is treated with colchicine for acute gouty ...
Tubulin polymerization

Block 4/Question#22
A 57-year-old woman is brought to the emergency department ...
Ninth

Block 4/Question#23
An investigator is studying the regulation of pulmonary ...
Intravenous infusion of 0.9% saline for 5 minutes

Block 4/Question#24
A 56-year-old man undergoes a renal transplant. Five minutes ...
IgG plus complement

Block 4/Question#25
An 80-year-old woman cannot concentrate her urine above 450 ...
2.0

Block 4/Question#26
The immunosuppressive agent cyclosporin A (CsA) is a potent ...
Interleukin-2 (IL-2) gene transcription

Block 4/Question#27
A 65-year-old woman is being treated in the hospital for ...
“The two of you seem to have a very important relationship. Of course you may stay together.”

Block 4/Question#28
A 56-year-old man undergoes surgical resection of the ...
Release of cholecystokinin

Block 4/Question#29
A 22-year-old man comes to the physician because of a 2-month ...
Formation of destructive free radicals

Block 4/Question#30
A 5-year-old boy is admitted to the hospital because of ...
ApoC-II

Block 4/Question#31
A 48-year-old woman comes to the physician because of a ...
Paracrine stimulation of osteoclasts by osteoblasts

Block 4/Question#32
A 19-year-old college student says he hears voices." He was ...
Risperidone

Block 4/Question#33
A female newborn delivered at 26 weeks' gestation is found to ...
Retina

Block 4/Question#34
A healthy 8-year-old boy is brought to the physician by his ...
Stimulation of the release of biogenic amine neurotransmitters

Block 4/Question#35
A 50-year-old woman is admitted to the hospital because of a ...
Didanosine (ddI)

Block 4/Question#36
A 45-year-old man comes to the physician because of ...
Chondrosarcoma

Block 4/Question#37
A 66-year-old right-handed woman develops the acute onset of ...
Area labeled 'B' (Internal capsule)

Block 4/Question#38
A 62-year-old woman is brought to the physician by her ...
Instruct the patient to keep notes and lists to help her memory

Block 4/Question#39
A 46-year-old man comes to the physician because of a 2-month ...
1/15

Block 4/Question#40
A study is conducted to assess the normal mean serum urea ...
500 Men from a list of patients scheduled to be examined by a urologist

Block 4/Question#41
A 66-year-old man with stage IV colon cancer comes to the ...
Loperamide

Block 4/Question#42
A 20-year-old primigravid woman at 12 weeks' gestation comes ...
Multifactorial

Block 4/Question#43
A 4-year-old boy falls and lacerates his lower leg to the ...
Formation of fibrin clot

Block 4/Question#44
A 28-year-old woman with chronic renal failure (creatinine ...
Furosemide

Block 4/Question#45
During an experiment, an investigator observes that glutamate ...
NMDA receptors are blocked by Mg2+ at the resting membrane potential

Block 4/Question#46
A 14-year-old girl is brought to the physician for a ...
TP53

Block 4/Question#47
While lifting weights, a 24-year-old man develops a painful ...
Strangulation

Block 4/Question#48
A 75-year-old man with dementia, Alzheimer type, is brought ...
Encourage the family to come to a consensus based on their perception of the patient's wishes

Block 4/Question#49
A 76-year-old man comes to the physician because of a 2-week ...
Left thalamus

Block 4/Question#50
A 19-year-old woman is brought to the emergency department 30 ...
Scaphoid

Recent comments ...

... cantaloupe5 made a comment on nbme21/block1/q#3 (An investigator is studying the efficacy of distinct...)
 +0  upvote downvote
submitted by cantaloupe5(5)

Capsular polysaccharide vaccines are often conjugated to proteins to improve immunogenicity. Flagellin is the only answer choice that's a protein.

... wasabilateral made a comment on nbme21/block1/q#3 (An investigator is studying the efficacy of distinct...)
 +0  upvote downvote
submitted by wasabilateral(0)

I think they want you to think about how conjugate vaccine is made: polysaccharide + protein fragment (to induce T dependent immune response). Only flagellin is a protein (or at least sounds like one) in the option list.

... haliburton made a comment on nbme21/block1/q#4 (A 67-year-old man comes to the emergency department...)
 +0  upvote downvote
submitted by haliburton(-1)

EF2 is translational elogation factor 2, which is necessary for protein synthesis.

... haliburton made a comment on nbme21/block1/q#5 (A 45-year-old woman is brought to the emergency...)
 +0  upvote downvote
submitted by haliburton(-1)

wikipedia (apologies): The atmosphere is composed of 78% nitrogen and 21% oxygen. Since oxygen is exchanged at the alveoli-capillary membrane, nitrogen is a major component for the alveoli's state of inflation. If a large volume of nitrogen in the lungs is replaced with oxygen, the oxygen may subsequently be absorbed into the blood, reducing the volume of the alveoli, resulting in a form of alveolar collapse known as absorption atelectasis.

I chose cardiogenic edema, but I believe this is incorrect because there is no heart failure risk at this time, so the purpose of the PEEP is certainly not to push out fluid.

... hayayah made a comment on nbme21/block1/q#11 (A 27-year-old primigravid woman at 34 weeks'...)
 +0  upvote downvote
submitted by hayayah(43)

HELLP syndrome: Hemolysis Elevated Liver enzymes Low Platelets.

A manifestation of severe preeclampsia. Blood smear shows schistocytes. Can lead to DIC and hepatic subcapsular hematomas Ž rupture Ž severe hypotension.

... haliburton made a comment on nbme21/block1/q#13 (A 25-year-old man develops shortness of breath after...)
 +0  upvote downvote
submitted by haliburton(-1)

FA 2017: Chronic hypoxic pulmonary vasoconstriction results in pulmonary hypertension and RVH.

... est88 made a comment on nbme21/block1/q#20 (A 10-year-old girl develops fever, malaise, and loss...)
 +1  upvote downvote
submitted by est88(4)

Rabies Virus (rhabdoviridae)

Fever, encephalitis, drooling

... haliburton made a comment on nbme21/block1/q#20 (A 10-year-old girl develops fever, malaise, and loss...)
 +0  upvote downvote
submitted by haliburton(-1)

Rabies attacks the nicotinic Acetylcholine receptor, and travels retrograde via dynein motors after binding AChR, according to FA.

... hayayah made a comment on nbme21/block1/q#22 (A 36-year-old man with AIDS elects to participate in...)
 +0  upvote downvote
submitted by hayayah(43)

Cysteine-cysteine chemokine receptor 5 (CCR5) is a protein found on the surface of CD4 cells.

... thechurchofbobbyhill made a comment on nbme21/block1/q#23 (A 59-year-old man comes to the physician because of...)
 +0  upvote downvote
submitted by thechurchofbobbyhill(0)

Hi- I don't have an explanation for this but I am also curious as to why this was the answer.

... est88 made a comment on nbme21/block1/q#23 (A 59-year-old man comes to the physician because of...)
 +1  upvote downvote
submitted by est88(4)

I believe its Squamous cell carcinoma. Its centrally located, smoker, and its a hilar mass. Keratin pearls.

... vonhippelindau made a comment on nbme21/block1/q#24 (A 23-year-old man drinks alcohol heavily on a...)
 +0  upvote downvote
submitted by vonhippelindau(0)

It’s acute alcohol consumption so fatty change more likely. Cellular swelling indicates alcoholic hepatitis which requires chronic alcohol consumption (See FA 2019 pg 385). At least that’s the logic I used to pick fatty change.

... hayayah made a comment on nbme21/block1/q#28 (A 47-year-old man is brought to the emergency...)
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submitted by hayayah(43)

Mixed venous oxygen saturation (SvO2) is measured in the pulmonary artery. SvO2 samples the true mixed venous blood leaving the right heart. Measurement of mixed venous oxygen saturation (SvO2) from the pulmonary artery has been advocated as an indirect index of tissue oxygenation.

In cardiogenic shock you have decreased CO --> decreased O2 delivery --> decreased SvO2.

... haliburton made a comment on nbme21/block1/q#31 (A 30-year-old woman comes to the office for a...)
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submitted by haliburton(-1)

there are two essential fatty acids: linoleic = omega 6, and alpha-linoleic = omega 3.

... halux made a comment on nbme21/block1/q#42 (A 36-year-old woman undergoes a total hysterectomy...)
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submitted by halux(1)

can some one please explain why is the hyperplasia?

beeip  Loss of negative feedback from resected ovaries leads to gonadotroph hyperplasia.
halux  so, the explanation is that in the absence of Estrogen negative feedback inhibition to LH and FSH, this leads to Gonadotrophs Hyperplasia at the Pituitary resulting in elevated LH and FSH secretion levels? I get busted by this one :/ Thanks in advance!
... beeip made a comment on nbme21/block1/q#42 (A 36-year-old woman undergoes a total hysterectomy...)
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submitted by beeip(7)

[moved to subcomment]

... halux made a comment on nbme21/block1/q#42 (A 36-year-old woman undergoes a total hysterectomy...)
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submitted by halux(1)

[moved to subcomment]

... cantaloupe5 made a comment on nbme21/block1/q#45 (An 18-year-old man comes to the physician because of...)
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submitted by cantaloupe5(5)

For this one you just had to know the glycolysis pathway. Stem told you 2,3-BPG is elevated, which is upstream of pyruvate kinase.

... est88 made a comment on nbme21/block1/q#45 (An 18-year-old man comes to the physician because of...)
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submitted by est88(4)

Pyruvate Kinase defect leads to decreased ATP leading to rigid RBCs and extra vascular hydrolysis. Increased levels of 2,3-BPG decreases hemoglobin affinity for O2.

... drmantistoboggan4 made a comment on nbme21/block1/q#47 (A 26-year-old woman (III-2) comes to the physician...)
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submitted by drmantistoboggan4(1)

It said it was fatal to males in utero, and the question asked about live born offspring. Since the males aren’t being born in the first place, I said 50% females and 0% males.

... haliburton made a comment on nbme21/block1/q#50 (A photograph is shown of a myelin-stained cross...)
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submitted by haliburton(-1)

this is a cervical spinal cord section. the cuneate fasciculus is intact (UE) vibration and proprioception, but the white section is the gracile fasciculus (LE) and is damaged. I think the lateral portion that is uneven is just natural/artifact.

... haliburton made a comment on nbme21/block2/q#2 (A 4-year-old girl is conscious but unable to breathe...)
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submitted by haliburton(-1)

https://ghr.nlm.nih.gov/condition/pseudocholinesterase-deficiency

"People with pseudocholinesterase deficiency may not be able to move or breathe on their own for a few hours after [fast-acting drugs, such as succinylcholine and mivacurium] are administered.

... lnsetick made a comment on nbme21/block2/q#3 (A 17-year-old boy returns to the locker room after...)
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submitted by lnsetick(1)
  • APocrine = your armpits smell like an APE
  • ceRUMen = there’s no ROOM in your ears since they’re full of wax
  • EC-CRYne = when you ECercise, your pores are CRYing
  • SEBaceous = SEBum is SEEPing out of your pores
... moneysacs made a comment on nbme21/block2/q#5 (A 2-week-old male newborn has a patent ductus...)
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submitted by moneysacs(0)

Why is does a PDA after birth result in "higher than normal left ventricular cardiac output" over increased "right ventricular PO2"? Does the pulm artery --> aorta shunt become reversed after birth, so higher oxygen aorta blood would flow back into the right ventricle? I get that more blood would be pumped to the left ventricle, resulting in RVH/LVH, but don't understand the O2 bit.

... heavy_neighborhood made a comment on nbme21/block2/q#5 (A 2-week-old male newborn has a patent ductus...)
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submitted by heavy_neighborhood(1)

PDA flows from the Aorta ==> Pulmonary arteries, by passing the RV so there is no change in O2 in the RV.

... cantaloupe5 made a comment on nbme21/block2/q#6 (A 38-year-old woman comes to the physician because...)
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submitted by cantaloupe5(5)

Recurrent kidney stones should include hyperparathyroidism on your differential, couple that with gastrinoma and you’re looking at MEN 1. Lipomas are also associated with MEN 1.

... _pusheen_ made a comment on nbme21/block2/q#8 (A 55-year-old man is diagnosed with renal artery...)
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submitted by _pusheen_(0)

I think this one is literally just asking what part of the kidney will be the most poorly perfused. That part would have the most renin. Also, the medulla doesn’t have JG cells so I guess that’s another reason why it couldn’t have the most renin.

sklawpirt  Exactly, it has to do with where in the kidney renin is released and requires a bit of knowledge of the artery branches that give rise to the afferent arteriole in the first place and where this branch point is located. http://anatomyforme.blogspot.com/2008/05/histology-of-kidney-lot-to-process.html Where renin production occurs in JGA cells, EPO production occurs in the renal peritubular interstitium (especially the proximal renal tubule, corext and some of the outer medulla.) Thus with the same questions stem it might ask where is concentration of EPO the highest? [And it would still be the cortex, with lower concentrations in the outer medulla, lowest concentration in the inner medulla, and none found in the papilla or renal pelvis.
hayayah  Actually, the renal medulla receives significantly less blood flow than renal cortex. So the medulla is the one that's very sensitive to hypoxia and vulnerable to ischemic damage. I don't think this question is related to "what area is the most poorly perfused." It's just knowing that renal artery stenosis is going to decrease blood flow to the kidney. JG cells sense the decrease in perfusion pressure and secrete renin. Knowing that renin is produced by the JG cells and that JG cells are in the cortex should be enough to answer this question.
... hayayah made a comment on nbme21/block2/q#8 (A 55-year-old man is diagnosed with renal artery...)
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submitted by hayayah(43)

Renal artery stenosis is going to decrease blood flow to the kidney. JG cells sense the decrease in perfusion pressure and secrete renin.

Renin is produced by the JG cells, JG cells are in the cortex (they are modified smooth muscle of the afferent arteriole).

... porky_pork_chop made a comment on nbme21/block2/q#12 (A 66-year-old woman comes to the physician because...)
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submitted by porky_pork_chop(0)

My reasoning was that it’d be diverticulitis due to the more acute history of presentation: “fever, chills, LLQ pain for 1 day.” Crohn’s should have a longer timeline of presentation; although the skip lesions made this one really tricky. Not sure how the gross pathology photograph plays in though ...

... nuts4med made a comment on nbme21/block2/q#12 (A 66-year-old woman comes to the physician because...)
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submitted by nuts4med(0)

I was thinking Chron’s because of the narrowing of the lumen and the picture seemed like there was creeping fat. Now that I think about it though, the LLQ and constipation should have led towards diverticulitis pretty quickly.

... logical_champion made a comment on nbme21/block2/q#12 (A 66-year-old woman comes to the physician because...)
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submitted by logical_champion(0)

I think it is good to note the demographics. The patient is female and old. That, along with the constipation, made me lean more towards diverticulitis. IBD usually develops in younger persons.

... vonhippelindau made a comment on nbme21/block2/q#12 (A 66-year-old woman comes to the physician because...)
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submitted by vonhippelindau(0)

I picked Crohn’s too. I think the severe constipation over 5 years distracted me.

haliburton  i think it is critical to remember that constipation is what caused the diverticulosis.
... hayayah made a comment on nbme21/block2/q#14 (A 30-year-old woman comes to the office because she...)
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submitted by hayayah(43)

Cretinism (congenital hypothyroidism) is the most common cause of treatable mental disability. Causes poor brain development.

... hayayah made a comment on nbme21/block2/q#16 (A 34-year-old woman comes to the physician because...)
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submitted by hayayah(43)

This pt has an ASD which is a "hole" between the LA and RA. Fixing it could damage the AV bundles.

... hayayah made a comment on nbme21/block2/q#19 (A 3-year-old boy who recently immigrated to the USA...)
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submitted by hayayah(43)

This pt has osteomalacia / rickets (since he's a kiddo). Caused by defective mineralization of osteoid (osteomalacia) or cartilaginous growth plates (rickets, only in children).

Most commonly d/t Vitamin D deficiency.

Children with rickets have pathologic bow legs (genu varum), bead-like costochondral junctions (rachitic rosary), craniotabes (soft skull).

  • Dec. Vitamin D (normal function is to reabsorb Ca2+ and PO4)

  • Dec. serum Ca2+

  • Dec.  serum PO4

  • Inc. PTH

... mattfoley_govtcheese made a comment on nbme21/block2/q#20 (A 14-year-old girl is brought to the physician by...)
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submitted by mattfoley_govtcheese(1)

The clues for trichotillomania were the death of her grandmother suddenly, since trichotillomania is often stress-induced. I also narrowed it down by it saying the hair was in different growth stages in the patchy areas, which makes sense if she’s plucking them out at different times.

Telogen effluvium is most common in middle-aged women, so she doesn’t fit the profile (but you’re right about it being caused by stress).

... haliburton made a comment on nbme21/block2/q#21 (A 35-year-old woman undergoes flexible...)
... mattfoley_govtcheese made a comment on nbme21/block2/q#24 (A 65-year-old man dies in a motor vehicle collision....)
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submitted by mattfoley_govtcheese(1)

My choice for Squamous Cell Carcinoma was guided by the central location of the tumor. To me, that didn’t look like the cavity you’d get with abscess but a huge tumor.

... lnsetick made a comment on nbme21/block2/q#24 (A 65-year-old man dies in a motor vehicle collision....)
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submitted by lnsetick(1)

I don’t think it was cavitary; I think that was just the bronchus. I think abscesses tend to be smaller, and wouldn’t affect the surrounding parenchyma much. I wasn’t super confident in picking squamous cell carcinoma, but I did know that squamous cell carcinoma tends to be a centrally-located lung tumor.

... hayayah made a comment on nbme21/block2/q#26 (A healthy 32-year-old woman at 35 weeks' gestation...)
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submitted by hayayah(43)

Stretch or dilation of the cervix and vagina are strong stimuli for oxytocin secretion, mediated by neural pathways called the Ferguson reflex.

Article: https://www.sciencedirect.com/topics/neuroscience/ferguson-reflex

... haliburton made a comment on nbme21/block2/q#28 (A 64-year-old woman with type 2 diabetes mellitus...)
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submitted by haliburton(-1)

FA 2017: Fibrate ADRs include myopathy increased risk with statins, cholesterol gallstones

... frimmy_11 made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
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submitted by frimmy_11(-2)

Muscle protein breaks down into the amino acid alanine which enters Cahill Cycle to form glucose ...

... volcanobuns made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
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submitted by volcanobuns(0)

@frimmy_11 Why would protein break down after only 20 hours? Shouldn’t fat be the major contributor now? Also if protein is being used, then why isn’t valine the choice? It’s also glucogenic.

... assoplasty made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
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submitted by assoplasty(3)

Fats are ketogenic (except odd chain FA), so they produce ketones for energy production (Acetyl-CoA) rather than glucose. If the question asked what the primary source of energy production was, it would still be glycogen (and not ketones), because this is within 24 hours. However after 24 hours the answer could be ketone bodies. Regardless, the question specifically said the pt had a serum glucose of 100, indicating that we are looking for something that provides a substrate for gluconeogenesis.

During periods of starvation, substrates for gluconeogenesis come from two sources: (1) breakdown of existing muscle, or (2) via odd-chain FA through propionyl-CoA. (*Valine also feeds into propionyl CoA, but is not involved during starvation --> see below)

(1) The alanine-pyruvate cycle provides this (glutamine in muscle + pyruvate --> alanine --> goes to liver --> transamination to alpha-ketoglutorate --> pyruvate is separated from glutamine --> glutamine goes to urea cycle, pyruvate goes on to gluconeogenesis). Lactate can also be used (this could have been a right answer if it were listed).

(2) Odd chain FAs are also glucogenic, but stearic acid (provided in the answer choice) isn’t odd chain, so it is only ketogenic and can be ruled out.

Although valine (and other branched a.a.) feed into Propionyl-CoA, they are not used in starvation because starvation strictly relies on hepatic gluconeogenesis. These a.a. are not metabolized in the liver because the liver lacks branched-chain a.a. transferase enzyme. In First Aid, Biochem section, under Fasting/Starvation, in both the “fasting state” (which is within the time frame of this question), or the “starvation state,” both utilize hepatic gluconeogenesis. My assumption is that valine is used during regular metabolism, and not during periods of starvation.

... hayayah made a comment on nbme21/block2/q#29 (A healthy 25-year-old man is participating in a...)
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submitted by hayayah(43)

P. 91 of FA has a quick explanation for this!

Basically once you're in a starving state there's still hepatic gluconeogenesis going on (as well as using FFA) but the gluconeogenesis is coming from peripheral tissue lactate and alanine.

... vlodkadrinker made a comment on nbme21/block2/q#31 (A 37-year-old man is brought to the emergency...)
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submitted by vlodkadrinker(1)

why? like does my med school suck or am I just that dumb cuz we never learned anything like this

sklawpirt  I think its just that the patient is CONSCIOUSLY experiencing chest pain. Because he is consciously feeling the pain and would be able to directly point to it (and that it is not referred visceral pain) it has to be a somatic afferent nerve fiber. This narrows it down exclusively to the intercostal nerve exc;usively. https://en.wikipedia.org/wiki/Intercostal_nerves IMportant to the patients "right sided chest pain" is his history of MVA and x-ray confirming multiple rib fractures. I think this is correct? Does that make sense ? All of the other choices do not carry SA fibers in that area
... hayayah made a comment on nbme21/block2/q#31 (A 37-year-old man is brought to the emergency...)
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submitted by hayayah(43)

With this question, I think they want you to recognize that the patient isn't having chest pain related to the heart. They emphasize several rib fractures and a pneumothorax but don't indicate any heart damage (lack of adventitious sounds = no pulmonary edema indicated or a lung issue related to heart problem).

The pericarditis is what's innervated by the phrenic n. Seeing as how his heart is fine, the fractured ribs are probably what are causing him pain via the intercostal nerves.

... haliburton made a comment on nbme21/block2/q#33 (A 68-year-old man comes to the physician because of...)
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submitted by haliburton(-1)

from AAFP ED of mixed organic and psychogenic origin is common. Psychogenic causes are more likely when the patient has normal erections with masturbation or when nocturnal penile tumescence is normal.

... haliburton made a comment on nbme21/block2/q#35 (A 4-month-old female infant is brought to the...)
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submitted by haliburton(-1)

This is water intoxication. https://www.ncbi.nlm.nih.gov/pubmed/1877579

... wasabilateral made a comment on nbme21/block2/q#39 (A 64-year-old man with bronchospastic pulmonary...)
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submitted by wasabilateral(0)

This is what I thought but not sure if it’s correct. There is a UWorld q where it describes co-administration of cortisol and epinephrine. Cortisol significantly enhances the effect of epi because cortisol has a permissive effect on maintaining the adrenergic receptors.

... 5thgencephalosporin made a comment on nbme21/block2/q#39 (A 64-year-old man with bronchospastic pulmonary...)
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submitted by 5thgencephalosporin(0)

“The combination of a long-acting beta 2 agonist (LABA) and an inhaled corticosteroid is more efficacious in asthma and [COPD] than [...] either alone. Corticosteroids may regulate beta 2 receptor function by increasing expression of the receptor, restoring G-protein/beta 2 receptor coupling, and inhibiting beta 2 receptor downregulation.”

https://www.ncbi.nlm.nih.gov/pubmed/16113435

... hayayah made a comment on nbme21/block2/q#44 (A 75-year-old man has the sudden onset of partial...)
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submitted by hayayah(43)

lower quadrantanopia: parietal lesion

vs upper quadrantanopia = temporal lesion

... hayayah made a comment on nbme21/block2/q#47 (A 55-year-old woman comes to the physician because...)
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submitted by hayayah(43)

Secondary hyperparathyroidism (usually d/t chronic renal failure).

Lab findings include ↑ PTH (response to low calcium), ↓ serum calcium (renal failure), ↑ serum phosphate (renal failure), and ↑ alkaline phosphatase (PTH activating osteoBlasts).

haliburton  also remember that in renal failure, 1-alpha-hydroxylase activity is down, so there will be less activation of 25-hydroxycholecalciferol to 1,25-hydroxycholecalciferol, which is a key mechanism causing hypocalcemia.
... hayayah made a comment on nbme21/block2/q#50 (A 65-year-old woman comes to the emergency...)
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submitted by hayayah(43)

Catheter placement:

https://aneskey.com/wp-content/uploads/2016/08/image00804.jpeg

Recall that the lung apex extends above the first rib.

... beeip made a comment on nbme21/block3/q#4 (A clinical trial is conducted to compare the...)
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submitted by beeip(7)

I might be the only person on earth who got this one wrong, but regardless:

"ITT analysis includes every subject who is randomized according to randomized treatment assignment. It ignores noncompliance, protocol deviations, withdrawal, and anything that happens after randomization."[1]

... feronie made a comment on nbme21/block3/q#7 (A 65-year-old man comes to the physician because of...)
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submitted by feronie(1)

Orchiectomy = ↓ testosterone production = ↓ DHT => prostate cells undergo apoptosis. (This mechanism is similar to using 5α-reductase blockers to treat BPH.)

Apoptosis is characterized by DNA fragmentation (pyknosis, karyorrhexis, karyolysis).

... _pusheen_ made a comment on nbme21/block3/q#7 (A 65-year-old man comes to the physician because of...)
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submitted by _pusheen_(0)

Alternatively, all the other options pointed to things that would actually increase testosterone production and its effects; orchiectomy would obviously not do that.

... cytocoins made a comment on nbme21/block3/q#7 (A 65-year-old man comes to the physician because of...)
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submitted by cytocoins(0)

With the drop in testosterone (and therefore DHT), some of the prostate cells will undergo apoptosis. Apoptosis = DNA fragmentation (180 bp segments).

... hayayah made a comment on nbme21/block3/q#8 (A 55-year-old woman is brought to the emergency...)
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submitted by hayayah(43)

Wernicke-Korsakoff syndrome. Don't have to be an alcoholic to get this, just usually is related to alcoholism / thiamine deficiency.

... haliburton made a comment on nbme21/block3/q#10 (A 30-year-old man has had intermittent severe lower...)
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submitted by haliburton(-1)

FA 2017: Urinary cyanide-nitroprusside test is diagnostic. not sure how to know that it was a red color, but maybe just the fact that red seemed like a positive test result.

link to more background but not necessarily helpful for this question

... cantaloupe5 made a comment on nbme21/block3/q#11 (A 50-year-old man is found dead in bed at home. His...)
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submitted by cantaloupe5(5)

Histology showed coagulative necrosis (preserved architecture of myocardial fibers) with neutrophil infiltration which hinted that the MI was within 24 hours. Most likely cause of death within first 24 hours of MI is arrhythmia. Myocardial rupture would also be visible on gross appearance of the heart, which they described in the stem.

... frimmy_11 made a comment on nbme21/block3/q#11 (A 50-year-old man is found dead in bed at home. His...)
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submitted by frimmy_11(-2)

Mottling and softening of anterior wall on autopsy suggests it was not older than 24 hrs. Death from fatal arrhythmia like V-fib most commonly occurs within one day of the MI. That said, once scar has formed in myocardial tissue it, too, can cause arrhythmia.

... volcanobuns made a comment on nbme21/block3/q#11 (A 50-year-old man is found dead in bed at home. His...)
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submitted by volcanobuns(0)

MI sudden death -> arrhythmia. The order of commonness is arrhythmia > cardiogenic shock > rupture.

... haliburton made a comment on nbme21/block3/q#15 (A 47-year-old man has jaundice. Laboratory findings...)
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submitted by haliburton(-1)

i think this is because bilirubin is a soluble liver breakdown product of heme, but has not entered the intestine/colon for gut bacteria conversion to stercobilin or urobilin. urobilin in urine is normal.

... lnsetick made a comment on nbme21/block3/q#16 (A 16-year-old boy is brought to the physician...)
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submitted by lnsetick(1)

I just remember Sattar saying MVP tends to be asymptomatic. Also, I think the kid complained specifically of coughing, and that made me really lean away from MVP.

... liltr made a comment on nbme21/block3/q#16 (A 16-year-old boy is brought to the physician...)
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submitted by liltr(0)

I choose MVP too, but this patient’s main symptom is cough only during exercise. This is more indicative of exercised associated asthma. You could see shortness of breath in MVP during exercise, but choosing MVP leaves the cough unaccounted for.

... haliburton made a comment on nbme21/block3/q#18 (An 83-year-old man comes to the physician because of...)
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submitted by haliburton(-1)

Bullous pemphigoid antigen must be hemidesmosome. FA: bulla are "bullow" the dermis (subepidermal blister). BP also yield "tense" bulla.

... haliburton made a comment on nbme21/block3/q#19 (A 25-year-old woman develops increasing shortness of...)
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submitted by haliburton(-1)

Peri- or postpartum cardiomyopathy (PPCM) is a rare, life-threatening heart disease of unclear origin and is characterized by heart failure of sudden onset between the final weeks of pregnancy and 6 months after delivery. link to pubmed The clinical picture of PPCM corresponds to a dilated cardiomyopathy (DCM) with signs of severe heart failure.

... drdoom made a comment on nbme21/block3/q#21 (A screening program is instituted for detection of...)
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submitted by drdoom(14)

2,500 students ... but you find out during your initial screen that 500 already have the disease. So, strikeout those people. That leaves 2,000 students who don’t have the disease.

Over the course of 1 year, you discover 200 students developed the infection. Thus:

200 new cases / 2,000 people who didn’t have the disease when you started your study = 10 percent

Tricky, tricky NBME ...

... drdoom made a comment on nbme21/block3/q#21 (A screening program is instituted for detection of...)
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submitted by drdoom(14)

Don’t forget that incidence is the number of new cases which emerge in an unaffected population. Incidence is trying to get at the question -> “In a given year, how many new people develop this disease?”

In other words, you cannot count people who already have the disease. You have to exclude those people from your calculation. You want to know, among all the people out there who DO NOT have the disease, how many times this year was someone (newly) diagnosed?

Said differently still, you don’t want to “double-count” people who developed the disease before your study. As an epidemiologist, that would screw up your sense of how infective or transmissible a disease is. You want to know, “from time1 to time2 how many new cases emerged?”

... drdoom made a comment on nbme21/block3/q#21 (A screening program is instituted for detection of...)
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submitted by drdoom(14)

Also consider this great description from the NIH’s MeSH database:

INCIDENCE: The number of new cases of a given disease during a given period in a specified population. It also is used for the rate at which new events occur in a defined population. It is differentiated from PREVALENCE, which refers to all cases, new or old, in the population at a given time.

https://meshb.nlm.nih.gov/record/ui?ui=D015994