Kim! Hi! Itโ€™s your dad!๐Ÿ‘‹ ▪ Khalilah, Iโ€™m proud of you for taking a risk for your dream.Everyoneโ€™s explanations tend to be so on-point, and the commiseration makes me feel better, too!Hi Hira. You are doing a good job!Hey Shariq! Doing a great job!                       want to add a fly-by? email us! ๐Ÿ˜Š
share email twitter ⋅ join discord whatsapp(2ck)
Free 120  NBME 24  NBME 23  NBME 22  NBME 21  NBME 20  NBME 19  NBME 18  NBME 17  NBME 16  NBME 15  NBME 13 
search for anything NEW!
NBME 13 Answers

Question#1 (reveal difficulty score)
A 77-year-old woman dies in the hospital ...
Interleukin-1 (IL-1)๐Ÿ”,๐Ÿ“บ

Question#13 (reveal difficulty score)
An 18-month-old boy is brought to the ...
Iduronate sulfatase๐Ÿ”,๐Ÿ“บ


Question#20 (reveal difficulty score)
A 3-year-old girl is found to have a grade ...
Ventricular septal defect๐Ÿ”,๐Ÿ“บ

Question#25 (reveal difficulty score)
A 32-year-old woman comes to the physician ...
Myasthenia gravis๐Ÿ”,๐Ÿ“บ




Question#30 (reveal difficulty score)
A 43-year-old man comes to the physician for ...
Low-calorie๐Ÿ”,๐Ÿ“บ

Question#41 (reveal difficulty score)
A 20-year-old man has cramping periumbilical ...
Interleukin-1 (IL-1)๐Ÿ”,๐Ÿ“บ

Question#43 (reveal difficulty score)
An 18-year-old man has had temperatures to ...
T lymphocytes๐Ÿ”,๐Ÿ“บ

Question#48 (reveal difficulty score)
A male newborn at 34 weeks' gestation is ...
Endothelium๐Ÿ”,๐Ÿ“บ


Question#6 (reveal difficulty score)
A female newborn is delivered at 34 weeks' ...
Nitric oxide๐Ÿ”,๐Ÿ“บ

Question#8 (reveal difficulty score)
A 5-month-old boy is brought to the physician ...
Thyroglossal duct๐Ÿ”,๐Ÿ“บ

Question#9 (reveal difficulty score)
In order to determine risk factors for death ...
Observational cohort study๐Ÿ”,๐Ÿ“บ



Question#38 (reveal difficulty score)
A 5-year-old boy is brought to the physician ...
Ischium๐Ÿ”,๐Ÿ“บ

Question#41 (reveal difficulty score)
A 23-year-old woman comes to the physician ...
Dextromethorphan๐Ÿ”,๐Ÿ“บ


Question#5 (reveal difficulty score)
A previously healthy 42-year-old Asian woman ...
Induction of cytochrome P450๐Ÿ”,๐Ÿ“บ

Question#6 (reveal difficulty score)
Homologous pairing of chromosomes in prophase ...
Crossing over๐Ÿ”,๐Ÿ“บ

Question#7 (reveal difficulty score)
A 32-year-old woman comes to the physician ...
Clomiphene๐Ÿ”,๐Ÿ“บ



Question#15 (reveal difficulty score)
A 33-year-old woman who is right-handed is ...
Voltage-gated Na+ channels๐Ÿ”,๐Ÿ“บ

Question#19 (reveal difficulty score)
A study is conducted to evaluate the onset ...
Population-based๐Ÿ”,๐Ÿ“บ

Question#21 (reveal difficulty score)
An autopsy is done on a 46-year-old woman who ...
Paraganglioma๐Ÿ”,๐Ÿ“บ



Question#35 (reveal difficulty score)
A 25-year-old woman undergoes a radical ...
Compression sleeve๐Ÿ”,๐Ÿ“บ

Question#39 (reveal difficulty score)
A young adult couple has been unable to ...
Seminal vesicles๐Ÿ”,๐Ÿ“บ


Question#2 (reveal difficulty score)
An 18-year-old woman with mild mental ...
Apo B๐Ÿ”,๐Ÿ“บ

Question#7 (reveal difficulty score)
A mouse melanoma, B-16, is highly metastatic. ...
Homing๐Ÿ”,๐Ÿ“บ


Question#20 (reveal difficulty score)
A previously healthy 32-year-old man is ...
Alcohol dehydrogenase๐Ÿ”,๐Ÿ“บ


Question#34 (reveal difficulty score)
A 33-year-old woman comes to the physician ...
Cortical hyperplasia๐Ÿ”,๐Ÿ“บ

Question#35 (reveal difficulty score)
A 55-year-old man with hepatic encephalopathy ...
Lactulose๐Ÿ”,๐Ÿ“บ



Question#46 (reveal difficulty score)
A 62-year-old man is brought to the emergency ...
Pulmonary edema๐Ÿ”,๐Ÿ“บ



Question#40 (reveal difficulty score)
A 46-year-old man receives the diagnosis of ...
Aorta๐Ÿ”,๐Ÿ“บ

Question#10 (reveal difficulty score)
A 40-year-old woman comes to the physician ...
Heteroplasmy๐Ÿ”,๐Ÿ“บ

Question#22 (reveal difficulty score)
A 9-year-old girl is brought to the emergency ...
Periosteum๐Ÿ”,๐Ÿ“บ


Question#41 (reveal difficulty score)
A 60-year-old man comes to the physician ...
Difficulty swallowing๐Ÿ”,๐Ÿ“บ

Question#15 (reveal difficulty score)
A previously healthy 35-year-old man comes to ...
Bromocriptine๐Ÿ”,๐Ÿ“บ

Question#12 (reveal difficulty score)
A 5-year old girl is brought to the physician ...
Cleavage and polyadenylation๐Ÿ”,๐Ÿ“บ

Recent comments ...

... drjungly made a comment on nbme13/block3/q#7 (32 yo woman, 5 years inability to conceive)
 +10 
submitted by drjungly(15)
unscramble the site ⋅ remove ads ⋅ become a member ($39/month)

lNmoar emnnhrrlmoaoo, male rsepm tdsuy dna lmaorn n:eesms sllti tcanโ€™ cnveecio then giev YTR hwit ilenhcom,pe thta si snAttongia at GRnH rrtopece at oap,sltamahyH oklcB srtoEeng mdteiade iionbiinht fo GnHR hncee nseIeacr lreseea of &i;&gn;.g;&ct&g&;>GHtng;ttRtg; HL uesgr ontiomaoinBourctiel prv - dwuol eb feuhpll if hte pt sah eiifnltryit deu ot SACERNEI RTLNOD CIEPSA. - is detsopp ni US due to lrcae ellc oarmcnaic ni nougy faleem norb ot rtiyenmE. lhoht tloireads - dinb gertseno tigtg&ttttio;&npg;e;c&iehgbrtg&;&; HnRG gnto&g&t;gtg;;;&t& HL sgur:e no s e.i(nuc iRks fo amltrieenod droMreaytiexg)osrcrecenponam - is sgeprtrnio โ€”bidn- eoeegsrntpro cp.(eo.nc.e.rtsenitmorpo fo mirngno eatfr llp)i

... jsmoov made a comment on nbme13/block4/q#2 (18 yo woman, mild mental retardation, 3 days decreased ability to see in reduced light)
 +8 
submitted by jsmoov(18)

This baby has abetalipoproteinemia. ("without Beta apolipoproteins"). Thus they will lack B-48 and B-100 and have absent levels of chylomicrons, VLDL, and LDL. Infants present with severe fat malabsorption and deficiencies of all fat soluble vitamins (ADEK). Lack of vitamin A renders them vulnerable to Retinitis pigmentosa and lack of VitE leads to spinocerebellar degeneration.

... skip_lesions made a comment on nbme13/block2/q#38 (5 yo boy, 6 months progressive clumsiness and fatigue)
 +3 
submitted by skip_lesions(12)

Muscle: Adductor magnus

Origin: Pubis, tuberosity of ischium

Insertion: Femur

Action: Adducts the thigh at the hip

... jsmoov made a comment on nbme13/block3/q#21 (Autopsy of 46 yo woman, adenocarcinoma of colon)
 +3 
submitted by jsmoov(18)

Positive staining for synaptophysin and chromogranin are immediate buzzwords for neuroendocrine tumors. Paragangliomas are the only type listed here.

Others would be small cell carcinoma of lung, carcinoid tumor, gastrinomas/insulinomas/etc, pheos, medullary carcinoma of thyroid.

... trazobone made a comment on nbme13/block3/q#21 (Autopsy of 46 yo woman, adenocarcinoma of colon)
 +3 
submitted by trazobone(59)

If anyone else is on the dumdum boat and didnโ€™t know what a paranganglioma was: a neuroendocrine tumor that begins in nerve cells, closely related to a pheochromocytoma

cheesetouch  Mayo clinic says 2 out of 1 million people have a paraganglioma. Talk about a zebra! +2
... jsmoov made a comment on nbme13/block3/q#31 (23 yo woman, type 1 diabetes mellitus, follow-up examination)
 +3 
submitted by jsmoov(18)

Halides are the elements in the 2nd the last column of the periodic table (F, Cl, Br, I, etc). Defective MPO prevents conversion of H2O2 into HOCl (a hydroxy-halide) which is aka bleach and the most powerful antimicrobial our phagocytes can synthesize

... thegooddoctor2 made a comment on nbme13/block1/q#1 (77 yo woman, dies in hospital after long illness)
 +2 
submitted by thegooddoctor2(1)

Remember, HOT T Bone Steak. IL-1 causes severe inflammation and is directly involved in the creation of the lytic lesion.

... iceberglettuce made a comment on nbme13/block3/q#15 (33 yo woman, right-handed, 3 days progressive weakness, numbness of arms and legs)
 +2 
submitted by iceberglettuce(10)

This one was a doozy. I think by saying "nerve studies show slow conduction velocity," they are referencing saltatory conduction impairment. Therefore they are asking us which channels are necessary for saltatory conduction - which would be voltage-gated Na+ channels.

... drjungly made a comment on nbme13/block3/q#19 (Study of onset and course of cardiovascular disease in African American men and women)
 +2 
submitted by drjungly(15)
unscramble the site ⋅ remove ads ⋅ become a member ($39/month)

rssheercare wtan ot oknw CV kisr touba ranfciA imaAcrne aopsilutnpo tbu do ton vaeh daat rof rvyee fpsreI.on a ehrsaecrre awnetd ot nrlae tewrheh bnieg ircntea niyctieth erecansi a iksr fo icrrtaalpu ees,sida ti wluod not be caipcrlta to tusdy eevry daiulidivn from hatt eiinchtyt . I,asentd teh eecaerrsrh hmgti eclets a alsmpe of hte lpoip.ntuoa A malpes si a lelsamr ropgu of ebmmsre of a alpiuotpno sceledte ot ntpsrreee het iooalup.npt nI dorer ot esu stttiascis to nreal inghts utabo teh oonu,ipltap het aepmls stum eb arndom. A onmrad mpales si oen in hiwhc rveye rebmme fo a ouipoplant ash na qleua eccanh of nbieg te.cseeld Teh stmo clymonmo ueds almsep is a eimpsl mndaor .paelms tI urqrisee ttha veyre spieolbs semalp fo the etedslce ezis sah na eqaul hcacne fo gbein u.sde

... skip_lesions made a comment on nbme13/block3/q#45 (25 yo man, cystic fibrosis, 3 days fever, cough, progressive shortness of breath)
 +2 
submitted by skip_lesions(12)

P. aeruginosa has been shown to form biofilm-like microcolonies in the lungs of CF patients making it difficult to treat with antibiotics.

... trazobone made a comment on nbme13/block4/q#21 (40 yo woman, brought to ER, 30 minutes after severe chest injuries in motor vehicle collision)
 +2 
submitted by trazobone(59)

I answered this via process of elimination.

A) Gliobastoma multiforme - no b/c that would need to show a tumor B) HSV encephalitis - would need to be in the temporal region and also doesnโ€™t quite fit with the 25 year seizure disorder history C) Mesial temporal sclerosis - i have no idea what this is really, but judging from โ€œsclerosisโ€ i assume there needs to be some signs of sclerosis which is not present in the photo D) Neonatal ischemic stroke - no she old E) Vascular malformation - could not think of a vascular disorder that was associated with seizures, but it makes sense b/c the picture shows a bunch of dilated spaces which I assumed are the vessels being malformed

trazobone  I answered this via process of elimination. A) Gliobastoma multiforme - no b/c that would need to show a tumor B) HSV encephalitis - would need to be in the temporal region and also doesnโ€™t quite fit with the 25 year seizure disorder history C) Mesial temporal sclerosis - i have no idea what this is really, but judging from โ€œsclerosisโ€ i assume there needs to be some signs of sclerosis which is not present in the photo D) Neonatal ischemic stroke - no she old E) Vascular malformation - could not think of a vascular disorder that was associated with seizures, but it makes sense b/c the picture shows a bunch of dilated spaces which I assumed are the vessels being malformed +2
... pharmtomed made a comment on nbme13/block1/q#1 (77 yo woman, dies in hospital after long illness)
 +1 
submitted by pharmtomed(2)

So I think where I got tripped up is that she does, indeed, have multiple myeloma (so there will be increased serum IgG), but the thing that is actually causing her bones to show the osteoclastic lesions shown in the image is IL-1 (osteoclast activating factor). Weird wording. Thanks NBME.

... schep made a comment on nbme13/block1/q#1 (77 yo woman, dies in hospital after long illness)
 +1 
submitted by schep(26)

I thought lytic bone lesion-->multiple myeloma-->hypercalcemia

but I suppose that calcium isn't involved in the process of creating the lytic lesion, that would be IL-1 and TNF

... jsmoov made a comment on nbme13/block1/q#19 (22 yo woman, 3 months painless, slowly enlarging mass on left neck)
 +1 
submitted by jsmoov(18)

Branchial cleft cysts typically occur due to failure of the 2nd branchial cleft to obliterate resulting in a persistent cervical sinus. Branchial cleft cysts will not move with swallowing and classically occur anterior to the sternocleidomastoid muscle

... trazobone made a comment on nbme13/block1/q#29 (43 yo woman, metastatic colon cancer, taking bevacizumab)
 +1 
submitted by trazobone(59)

This is straight up testing if you knew Ab nomenclature ๐Ÿ™„. -umab designates human origin while -omab designates murine origin. So bevacizumab is a humanized Ab. The other answer choice saying it was a murine Ab directed against VEGF was designed to trick you. Luckily I did not fall for such witchery.

trazobone  This is straight up testing if you knew Ab nomenclature ๐Ÿ™„. -umab designates human origin while -omab designates murine origin. So bevacizumab is a humanized Ab. The other answer choice saying it was a murine Ab directed against VEGF was designed to trick you. Luckily I did not fall for such witchery. IN CASE ANYONE TRIES TO SCRAMBLE +2
... victor_abdullatif made a comment on nbme13/block1/q#48 (Male newborn at 34 weeks gestation delivered vaginally)
 +1 
submitted by victor_abdullatif(5)

Diagnosis: strawberry hemangioma

Heme = blood -ang- = vessel -oma = benign mass

A benign tumor of capillaries, therefore the origin is endothelium

cheesetouch  NOTE: Endothelium derived from mesoderm. (I was mis-reading this as endoderm). +1
... schep made a comment on nbme13/block2/q#6 (Female newborn, delivered at 34 weeks gestation, advanced-care setting)
 +1 
submitted by schep(26)

FYI since I didn't know the difference

Nitric oxide=NO

Nitrous oxide=N2O

... trazobone made a comment on nbme13/block3/q#7 (32 yo woman, 5 years inability to conceive)
 +1 
submitted by trazobone(59)

Normal hormonal, male sperm study and normal semen: still canโ€™t conceive then give TYR (???) with clomiphene, that is antagonist at GnRH receptor at hypothalamus, block estrogen mediated inhibition of GnRH hence increase release of LH surge Bromocriptine - would be helpful if the pt has infertility due to INCREASE LPEDS CTIRAON (??? I am assuming its PROLACTIN) - is stopped in US due to clear cell carcinoma in young female born to term. Ethinyl estradiol - bind estrogen & GnRH; LH surge: no use. (Inc risk of endometrial carcinoma) Medroxyprogesterone - is progesterin bind progesterone eonis(oeeccn.rprpmot..t. (???) of morning after pill)

trazobone  Clomiphene: a SERM, antagonist at estrogen receptors in hypothalamus (FA18 637) +1
... l0ud_minority made a comment on nbme13/block3/q#14 (40 yo man, brought to ER, 1 hour after sudden onset of severe pain in left leg)
 +1 
submitted by l0ud_minority(1)

I got this wrong I thought Decreased Myosin Light Chain Phosphatase activity would play a factor from the long leg cast immobilization for 6 months. Not being able to use the leg would cause atrophy. But I was wrong.

scoresloth  same here +1
bugdrivergirl  I thought that was only for smooth muscle though +
... jsmoov made a comment on nbme13/block3/q#30 (Cluster of three cases of nosocomial pneumonia caused by <i>Klebsiella pneumonia</i>)
 +1 
submitted by jsmoov(18)

Klebsiella has a capsule and is spread through person-to-person contact (e.g. from patient to patient via the contaminated hands of healthcare personnel). "The bacteria are not spread through the air"

... skip_lesions made a comment on nbme13/block3/q#39 (Young adult couple, 2 years unable to conceive)
 +1 
submitted by skip_lesions(12)

Seminal vesicles contribute fructose to the ejaculate. Decreased fructose concentration may indicate an ejaculatory duct obstruction.

... mario made a comment on nbme13/block4/q#7 (Mouse melanoma, B-16, highly metastatic)
 +1 
submitted by mario(1)
unscramble the site ⋅ remove ads ⋅ become a member ($39/month)

isth lecsl lhduos be mste ellc nsaatptlr,n so onghim is the invneeornmt htat acetpc ehtm and osrhuni meht whit tghorw acstorf to rteaum

... skip_lesions made a comment on nbme13/block4/q#35 (55 yo man, hepatic encephalopathy, 24 hours of confusion and lethargy)
 +1 
submitted by skip_lesions(12)

Colonic bacteria convert lactulose into lactic acid and acetic acid, which acidifies colonic contents. This leads to the conversion of ammonia (NH3), which is a weak base, into its nonabsorbable protonated form, ammonium (NH4+). Once protonated, the positive charge prevents ammonium from crossing cell membranes, keeping the molecule in the colon. As the levels of ammonia in circulation gradually declines, the symptoms of hepatic encephalopathy improve

... iceberglettuce made a comment on nbme13/block4/q#36 (25 yo man, admitted to hospital for viral pneumonia)
 +1 
submitted by iceberglettuce(10)

Diffuse alveolar damage = ARDS -> alveolar hyaline membranes

... cheesetouch made a comment on nbme13/block2/q#22 (A 9-year-old girl is brought to the emergency...)
 +1 
submitted by cheesetouch(200)

2 places with osteoprogenitor cells are periosteum and endosteum. Stem cells from periosteum are involved in fracture healing, whereas those in the endosteum are involved in bone remodeling. Source: https://www.kenhub.com/en/library/anatomy/histology-of-bone

... trazobone made a comment on nbme13/block3/q#41 (A 60-year-old man comes to the physician because of...)
 +1 
submitted by trazobone(59)

SMH I was thinking alcoholic B12 loss of vibratory, so obvious now he has ALS. Hyperreflexia UMN sign, fasciculations LMN sign. And common cause of death is due to aspiration pneumonia because of dysphagia (LMN deficit). FA 2018 p 514

trazobone  Sorry dysphagia (UMN deficit) +
trazobone  SMH I was thinking alcoholic B12 loss of vibratory, so obvious now he has ALS. Hyperreflexia UMN sign, fasciculations LMN sign. And common cause of death is due to aspiration pneumonia because of dysphagia (UMN deficit). FA 2018 p 514 +
cheesetouch  UMN vs LMN is FA18 p 513 also! +1
... cv020496 made a comment on nbme13/block1/q#13 (18-month-old boy, 6 months progressive facial abnormalities, slow growth)
 +0 
submitted by cv020496(1)

Hurler syndrome (Auto Rec) symptoms - Developmental delay, gargoylism, airway obstruction, corneal clouding, hepatosplenomegaly. Deficient - ฮฑ-l-iduronidase accumulation of- Heparan sulfate,dermatan sulfate

Hunter syndrome (X-linked Rec) - Mild Hurler + aggressive behavior, no corneal clouding. deficient - Iduronate sulfatase Build up - Heparan sulfate,dermatan sulfate

... athenathefirst made a comment on nbme13/block1/q#20 (3 yo girl, grade 4/6, loud, harsh, high-pitched holosystolic murmur)
 +0 
submitted by athenathefirst(7)

Why is this VSD? Is it just because she is 3 years old? I was stuck between MVP, VSD.

schep  I picked VSD because of the description of the murmur-loud, harsh, holosystolic, radiates over precordium and palpable thrill at left sternal border (I think because high pressure blood is moving from LV-->RV so you can feel a thrill) MVP is late systolic, crescendo murmur with midsystolic click +1
castlblack  rule out all diastolic murmurs including -aortic regurg, -mitral stenosis, -PDA (no sound in diastole so cant be continuous). Rule out all murmurs that are heard on A and M sites, -aortic stenosis, -mitral regurg. Coarctation of the aorta is heard between the scapula I read so rule that out too. Rule out crescendo decrescendo murmurs, because holosystolic murmurs are like they sound: the same throughout systole. -pulmonic stenosis, -atrial septal defect. (AS has already been ruled out) You are now left with tricuspid regurg and VSD. Use harsh, high pitched descriptors to pick VSD. Tricuspid is described as blowing just like mitral regurg. Tricuspid regurg is a close candidate because it is heard in the same place as VSD, can be due to congenital malformation e.g. ebstein anomaly. It is also seen in rheumatic fever and endocarditis, but no other symptoms are mentioned so this question is leaning toward congenital malformation. +
... cv020496 made a comment on nbme13/block1/q#25 (32 yo woman, 1 month progressive shortness of breath and anxiety)
 +0 
submitted by cv020496(1)

Middle aged woman thinking autoimmune condition... Restrictive lung symptoms (decreased lung volumes) that get worse as the day progresses matches well with myasthenia gravis.

Chronic bronchitis and alpa1-antitrypsin deficiency both cause obstructive lung disease.

... schep made a comment on nbme13/block1/q#26 (4 yo boy, brought to ER, 1 hour headache, nausea, vomiting, dizziness)
 +0 
submitted by schep(26)

carbon monoxide inhibits the final step of ETC, cytochrome oxidase

... skip_lesions made a comment on nbme13/block1/q#30 (43 yo man, routine health maintenance examination)
 +0 
submitted by skip_lesions(12)

Patient is obese with a BMI of 30 and a major risk factor for T2DM is obesity and high-calorie diet.

castlblack  what is wrong with low carbohydrate? Carbs raise insulin after all +6
trazobone  I also have this question ^^^. My guess is the question says which diet is most effective so if he had a low-carb diet but high in everything else, then he wonโ€™t lose weight. Versus no loopholes in a low-calorie diet +2
... specialist_jello made a comment on nbme13/block1/q#41 (20 yo man, cramping periumbilical pain; pain shifts to right lower quadrant)
 +0 
submitted by specialist_jello(26)

I get HOT T Bone STEAK IL 1 for fever

but 90% neutrophils, why cant it be LTB4 neutrophil chemotaxis?

dentist  i picked LTB4 i guess the question itself is "which causes the patient's fever and leukocytosis" LTB4 wouldn't be a direct cause of fever. dumb question +
... meryen13 made a comment on nbme13/block1/q#43 (18 yo man, 8 days temperature of 38.3 C, sore throat, cervical lymph node enlargement)
 +0 
submitted by meryen13(23)

https://www.slideshare.net/csbrprasad/imn-csbrp-54556104 i found this link helpful. the atypical cd8+ lymphocytes are diagnostic for EBV

castlblack  Despite being dormant in monocytes (premature macrophages), causing B cell immortality and B cell lymphomas, EBV causes atypical T cells in the blood. +2
... cheesetouch made a comment on nbme13/block2/q#6 (Female newborn, delivered at 34 weeks gestation, advanced-care setting)
 +0 
submitted by cheesetouch(200)

Nitric oxide (NO) is a vasodilator, thus helping to decrease the high pressure of the pulmonary vessels. Pulmonary hypertension has excess vasoconstrictors (endothelin), and deceased vasodilators (NO, prostacyclins). FA18 p 661

... jsmoov made a comment on nbme13/block2/q#8 (5-month-old boy, 5 days difficulty feeding)
 +0 
submitted by jsmoov(18)

Midline mass that moves with swallowing = thyroglossal duct cyst

... cv020496 made a comment on nbme13/block2/q#21 (36 yo man, HIV seropositive, 2 weeks nonproductive cough)
 +0 
submitted by cv020496(1)

P. jiroveci: Causes Pneumocystis pneumonia (PCP), a diffuse interstitial pneumonia. Yeast-like fungus (originally classified as protozoan). Inhaled. Most infections are asymptomatic. Immunosuppression (eg, AIDS) predisposes to disease. Diffuse, bilateral ground-glass opacities on CXR/CT. Diagnosed by lung biopsy or lavage. Disc-shaped yeast seen on methenamine silver stain of lung tissue

Treatment/prophylaxis: TMP-SMX, pentamidine, dapsone (prophylaxis only), atovaquone. Start prophylaxis when CD4+ count drops to < 200 cells/mm3 in HIV patients.

... trazobone made a comment on nbme13/block2/q#41 (23 yo woman, 3 weeks persistent cough worsened by cold air)
 +0 
submitted by trazobone(59)

A) Codeine - common in cough syrup but itโ€™s a weak agonist at mu and delta receptors, so thereโ€™s potential for substance abuse.
B) Dextromethorphan - a cough suppressant with low potential for abuse and does not cause constipation; antagonizes NMDA receptors (not mu kappa or delta receptors).
C & D) Hydromorphone & oxycodone -- potent opioids used to treat moderate to severe pain (I am assuming they work at mu receptors but itโ€™s not in FA so ๐Ÿคท๐Ÿปโ€โ™€๏ธ)

E) Tramadol - a weak opioid agonist used for neuropathic pain, acts by reuptake of NE and 5HT

trazobone  A) Codeine - common in cough syrup but itโ€™s a weak agonist at mu and delta receptors, so thereโ€™s potential for substance abuse. B) Dextromethorphan - a cough suppressant with low potential for abuse and does not cause constipation; antagonizes NMDA receptors (not mu kappa or delta receptors). C & D) Hydromorphone & oxycodone -- potent opioids used to treat moderate to severe pain (I am assuming they work at mu receptors but itโ€™s not in FA so ๐Ÿคท๐Ÿปโ€โ™€๏ธ) E) Tramadol - a weak opioid agonist used for neuropathic pain, acts by reuptake of NE and 5HT IN CASE ANYONE TRIES TO SCRAMBLE +1
... cv020496 made a comment on nbme13/block2/q#45 (54 yo man, squamous cell carcinoma of right lung)
 +0 
submitted by cv020496(1)

Loss of heterozygosity: If a patient inherits or develops a mutation in a tumor suppressor gene, the complementary allele must be deleted/mutated before cancer develops. This is not true of oncogenes. (FA)

... iceberglettuce made a comment on nbme13/block3/q#5 (42 yo Asian woman, brought to ER, 24 hours nausea, vomiting, progressive lethargy)
 +0 
submitted by iceberglettuce(10)

Chronic EtOH induces CytP450. Acetaminophen metabolism yields NAPQI, which is highly hepatotoxic.

CytP450 inducers: CRAP GPS

Carbamazepine Rifampin Alcohol (chronic) Phenytoin

Griseofulvin Phenobarbitol St. John's wart

... imkingran made a comment on nbme13/block3/q#6 (Homologous pairing of chromosomes in prophase I)
... imkingran made a comment on nbme13/block3/q#14 (40 yo man, brought to ER, 1 hour after sudden onset of severe pain in left leg)
 +0 
submitted by imkingran(1)

FA 2020 pg 206 - Cellular Adaptations - Atrophy

... imkingran made a comment on nbme13/block4/q#7 (Mouse melanoma, B-16, highly metastatic)
 +0 
submitted by imkingran(1)

This homing phenomenon may be related to tumour cell recognition of specific โ€œexit sitesโ€ from the circulation or to awareness of a particularly favourableโ€”or forbiddingโ€”โ€œsoilโ€ of another tissue. This may occur because of an affinity that exists between receptor proteins on the surface of cancer cells and molecules that are abundant in specific tissues.


FA 2020, pg 221, "Hallmarks of Cancer"

Metastasis is defined by distant spread via blood/lymphatics --> binding to endothelium --> extravasation & homing.

Since metastasis to only one organ has been affected, it's safe to say this liver cell surface antibody has affected "homing" towards the liver.

... trazobone made a comment on nbme13/block4/q#7 (Mouse melanoma, B-16, highly metastatic)
 +0 
submitted by trazobone(59)

This cells should be stem cell transplant so homing is the environment that accept them and nourish them with growth factors to mature

trazobone  I donโ€™t understand what I unscrambled. This does not apply to the question stem? +
trazobone  Apparently there is something called โ€œhepatic homingโ€ that occurs with mononuclear inflammatory cells I have never heard such a thing +1
... cheesetouch made a comment on nbme13/block4/q#21 (40 yo woman, brought to ER, 30 minutes after severe chest injuries in motor vehicle collision)
 +0 
submitted by cheesetouch(200)

Symptoms of brain AVMS (arteriovascular malformations) include seizures. Brain avms can be found in HHT (hereditary hemorrhagic telangiectasia / Osler Weber Rendu syndrome). More info here: https://www.mayoclinic.org/diseases-conditions/brain-avm/symptoms-causes/syc-20350260 & at curehht.org

... cv020496 made a comment on nbme13/block4/q#34 (33 yo woman, 16 kg weight gain over 6 months despite dieting)
 +0 
submitted by cv020496(1)

ACTH-secreting pituitary adenoma (Cushing disease); paraneoplastic ACTH secretion (eg, small cell lung cancer, bronchial carcinoids)โ€”result in ACTH, bilateral adrenal hyperPLASIA. Cushing disease is responsible for the majority of endogenous cases of Cushing syndrome. Cortisol produced in zona fasciculata in cortex.

... scoresloth made a comment on nbme13/block4/q#42 (64 yo woman, 6 months heartburn, difficulty swallowing solid food and liquid)
... cv020496 made a comment on nbme13/block4/q#42 (64 yo woman, 6 months heartburn, difficulty swallowing solid food and liquid)
 +0 
submitted by cv020496(1)

Scleroderma (systemic sclerosis) - Triad of autoimmunity, noninflammatory vasculopathy, and collagen deposition with fibrosis. Commonly sclerosis of skin, manifesting as puffy, taut skin A without wrinkles, fingertip pitting B . Also sclerosis of renal, pulmonary (most common cause of death), cardiovascular, GI systems. 75% female. 2 major types:

Diffuse sclerodermaโ€”widespread skin involvement, rapid progression, early visceral involvement. Associated with anti-Scl-70 antibody (anti-DNA topoisomerase I antibody).

Limited sclerodermaโ€”limited skin involvement confined to fingers and face. Also with CREST syndrome: Calcinosis C , anti-Centromere antibody, Raynaud phenomenon, Esophageal dysmotility, Sclerodactyly, and Telangiectasia. More benign clinical course

... meryen13 made a comment on nbme13/block2/q#20 (an investigator is studying the human immune response)
 +0 
submitted by meryen13(23)

i was so confused by this question. is this because the rest are human antigens, so why would we have antibodies against them? but HPV is antibody toward E6 is foreign...?

topgunber  im going with this explanation. the rest : cd19, her2, Prostate acid phosph, tyrosinase are all endogenous molecules. makes sense that viral protein e6 has the highest immunogenicity. +7
... ejahan made a comment on nbme13/block1/q#19 (A 1-year-old girl is brought to the physician...)
 +0 
submitted by ejahan(0)

I think Cheidak-Higashi syndrome -albinism, pyogenic infections, giant granules in granulocytes, cytopenia => defect in lysosomal trafficking regulator gene (LYST) => microtubule dysfunction in phagolysosome fusion.

... imkingran made a comment on nbme13/block1/q#40 (A 46-year-old man receives the diagnosis of squamous...)
 +0 
submitted by imkingran(1)

Top 1/3: Esophageal branches of inferior thyroid artery, which is a branch of the thyrocervical trunk (option E)

Middle 1/3: Esophageal branches of thoracic part of aorta (option B)

Bottom 1/3: Esophageal branches of left gastric artery (which is branch of celiac trunk, which is branch of aorta) (option A)


FA 2020 pg 364: abdominal aorta --> celiac trunk --> left gastric --> esophageal arteries