Welcome to meningitisโs page.
Contributor score: 644
Comments ...
gh889
I think you're right, FA2019 pp444 even states that sensory to the scrotum is via the Genitofemoral nerve
+5
dr.xx
you mean, pure luck? :)
+13
nor16
same here, Glutamine is a NH3 (-amin) donor, so guessing made sense
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meningitis
sorry about the formatting, they were supposed to be bullets not italic.
+30
drdoom
looks good to me! ;) instead of asterisks try using the plus sign for unordered lists; the system gets confused sometimes because the asterisk is also for italics ๐
+2
meningitis
Yeah, I noticed :s
Oh, I didnt know the + sign did that! Very much appreciated, I will try that next time.
+1
meningitis
the prevalence of the exposure and the health outcome are measured at the same time. You are basically trying to figure out how many people in the population have the disease and how many people have the exposure at one point in time.
Case Control would determine ODDS ratio
Cohort would determine Relative Risk
+3
makinallkindzofgainz
I ruled out duodenum because it's towards the right side, and I ruled out body of pancreas because that's basically midline. We are talking about the left lower kidney, which is by the spleen and splenic flexure.
Idk if this logic checks out, but I got it right
+
chaosawaits
The only part that frustrated me about this picture is that the stomach is incredibly variable in its final resting place within the population and, as the picture provided on this page shows, the splenic flexure is a bit lateral to the kidneys. So I overthought it and chose not-so-wisely
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kevin
just for people who are taking exam this year, ewing is now understood to be mesenchymal stem cell neoplasm (uworld)
+3
meningitis
Sorry about the format, it came out wrong but I hope his helps.
+2
gh889
According to FA2019, stage 2 ends at 11, stage 3 starts 11.5-13, and stage 4 starts at 13-15, where did you get your info from?
+1
meningitis
You can change it to ENDS at 11, ENDS at 13, ENDS at 14... I simply have it as a range just like you stated in a couple of them. The importance is in how the kid presents because he/she will have some things mature but others not, the age will vary in questions.
+1
endochondral1
stage 3 breast mound is for females not males btw
+4
endochondral1
see pg. 635 in FA it just pubertal. Idk if that correlates to the same stage as females
+1
angelaq11
this is just too funny, I LOVE it! xD
+4
snripper
While this is impressive, this doesn't help with answering the question.
+2
yng
Pseudogynecomastia (False gynecomastia): this has nothing to do with puberty or hormones. Simple d/t the fast some guys have extra fat in chest area, making it look like they have breasts. The boy weight at 60 percentile while height at 50 percentile.
+1
hello
Where in Pathoma? I couldn't find it.
+2
almondbreeze
also sketchy says that thiazide s decrease the amount of lithium cleared--> lithium toxicity
+2
paperbackwriter
Agh confused as well because FA2019 (pg 562) says that thiazides are implicated in lithium toxicity D:
+1
paperbackwriter
OOPS, please ignore last comment. I just realized that this Q stem never mentioned lithium. And on top of that @meningitis mentioned that amiloride is used if lithium induced. Apologies.
+1
jaramaiha
Question is nephrogenic DI. ADH is increased but kidney's aren't reacting, mutated receptors. In which the Tx is HCTZ
+1
mantarayray
I think that it's not ANP because ANP will cause a loss of Na but water will follow (they usually go together), whereas ADH will cause absorption of only water and will cause hyponatremia
except only thought this post getting the question wrong :")
+5
mantarayray
Oops sorry the formatting is confusing: I think that it's not ANP because ANP will cause a loss of Na but water will follow (they usually go together), whereas ADH will cause absorption of only water and will cause hyponatremia.
+4
pg32
@mantaray pretty sure you are right and that is the only way to get this question correct. Remembering that Na concentration really is a measure of water balance is key. If the pt is hyponatremic, that just means they have too much water in the blood, which is caused by ADH. If the patient was hypoVOLEMIC, that might mean they are losing too much Na.
This is illustrated by pts with SIADH. They are hyponatremic, but euvolemic, meaning that they have too much water (hyponatremia from the ADH) but their Na balance is ok (due to excretion of Na via ANP/BNP)
+1
avocadotoast
We need to be thinking about how heart failure is a condition with a low effective circulating volume. Our patient had an MI and now his heart cant keep up with the volume (low CO), leading to congestion. When congestion occurs, water is pushed into the interstitial spaces and isn't circulating in the arterial system. For that reason, the body ramps up the RAAS and ADH despite an actual increase in body water. This is a non-osmotic release of ADH. At this point plasma sodium levels are determined by relative intake and losses and hyponatremia is common in these patients because of that. Also, ANP and BNP don't hold a candle to the RAAS.
+1
zevvyt
and just to note answer b) "induction of histamine release" DOES happen , but it's not the "Initial Event" that the question asks for
+1
unknown001
there you go, another introducer of confusion who dislikes straightforward questions
+
medschul
Would pheo have a normal resting BP though?
+16
meningitis
I was trying to justify these tricky questions but very true medschul.. It shouldn't have normal resting BP. Sometimes it seems these NBME always have a trick up their sleeve. Im getting paranoid lol
+
nala_ula
The reason why the patient probably has normal HTN is because Pheochromocytoma has symptoms that occurs in "spells" - they come and go. Apparently in that moment, when the physician is examining her, she doesn't have the HTN, but like @meningitis explained, so many adrenergic hormones around leads to double the vasoconstriction when the patient stands up.
+10
meningitis
Thank you @nala_ula for your contribution! Really filled in the gap Iwas missing.
+2
nala_ula
No problem! Thank you for all your contributions throughout this page!
+2
mjmejora
I thought the pheochromocytoma was getting squeezed during sitting and releasing the epinephrine then. kinda like how it can happen during manipulation during surgery. Got it right for sorta wrong reasons then oh well.
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llamastep1
When she sits in the examination table there would be a normal activation of the sympathetic system from the stress of getting examined which is amplified by the pheo. Cheers.
+
sammyj98
UpToDate: Approximately one-half have paroxysmal hypertension; most of the rest have either primary hypertension (formerly called "essential" hypertension) or normal blood pressure.
+
notyasupreme
Damn llama, that is WAYYY too much of an inference. Maybe if they said she was nervous in general or something, but not everyone gets stressed out by a doctor hahaha
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jakelong377
Itโs not about being stressed infront of doctor. When u stand sympathetics activate to prevent orthostatic hypotension, to counter it adrenal medulla released catecholamines so much so that pheochromocytoma patients would appears with flushed skin n such
+
Subcomments ...
etherbunny
When you say MH is "often seen" in patients receiving anesthesia, its VERY rare.
+
meningitis
Im thinking he meant "often seen" in question stems.. not the actual incidence
+
meningitis
For that same reason (not an NSAID) it doesn't reduce inflammation so it cant be used for Gout.
+7
meningitis
And I think Indomethacin is associated with anaphylactic reactions in patients with aspirin-sensitive asthma and aspirin allergies. Can anyone confirm?
+1
link981
How many other's like me didn't see "allergic to aspirin"? FML
+3
hyperfukus
OMFG me too i just got so mad and questioned my whole life at least its cuz i can't read not bc i don't understand :(((((
+1
an1
Actually, from what I recall from UW, acetaminophen actually is an NSAID... it only acts centrally though. From FA: "Reversibly inhibits cyclooxygenase, mostly in CNS. Inactivated peripherally." But for that reason, It wouldn't be helpful for gout because it can't do squat in the periphery, which is where gout accumulates.
+
sympathetikey
Probably a Strawberry Hemangioma since she's a baby
+10
meningitis
Can anyone explain what is option A?
+2
redvelvet
bc, it's a benign "capillary" hemangioma, we can see "thin-walled blood vessels with narrow lumens filled with blood and separated by connective tissue". It sounds similar to "arterioles in a fibrous stroma" but it's capillary.
+1
peridot
@meningitis I believe option A ("arterioles in a fibrous stroma") is describing an angiofibroma. The name angiofibroma already tells you that there is some component of fibrotic tissue involved, whereas in this case of strawberry hemangioma, the name tells you that it's more like pure blood vessels (capillaries in this case).
+5
madamestep
@periodt Also those are pretty much always going to be in teen boys with recurrent nosebleeds!
+
meningitis
To make sure, palpable Gallbladder is more in cholangiocarcinoma and Pancreatic Cancer? And if it were non-tender, could palpable gallbladder mean gallstones?
+9
yb_26
@meningitis, it is a Courvoisier sign of pancreatic adenocarcinoma: jaundice + palpable, nontender gallbladder
+3
an1
what's the periumbilical ecchymosis? could this be caput medusa?
+
an1
and what about tenderness of the epigastrium on palpation?
+
fatboyslim
@an1 Periumbilical ecchymosis is likely referring to Cullen's sign which is commonly associated with hemorrhagic pancreatitis. Another sign associated with hemorrhagic pancreatitis is Grey Turner sign, which is ecchymosis around the flanks bilaterally.
+
meningitis
Why others not it:
Anticipation: Trinucleotide repeats; CAG (Huntington), CTG (Myotonic dyst), GAA (ataxia telangiectasia), CGG(Fragile X)
Chromosomal rearrangement: Many but can think of Trisomy 21, BCR-Abl, etc
Imprinting: Prader willi, angelman
Loss of heterozygosity: loss of a single parent's contribution to part of its genome. A common occurrence in cancer, it often indicates the presence of tumor suppressor gene in the lost region.
+3
kai
trinucleotide repeats are not associated with breast cancer
Neither are chromosomal rearrangements
BRCA1,2 tumor supressor genes are associated with breast cancer, which is why I chose E, but I guess I should have bought the new First Aid..........
+
tulsigabbard
So is the amplification of the receptors unrelated to BRCA 1, 2? I'm still stuck on this as Sketchy states that breast cancer falls under the "two-hit" model.
+
tallerthanmymom
@tulsigabbard I think one of the keys here is the question stem; " what is the most likely cause of the OVERexpression in this pts tumor cells?" --> I think that the "2-Hit" model would lead to UNDERexpression of a tumor suppression gene rather than overexpression. Whereas amplification would cause OVERexpression of the HER2/estrogen and progesterone receptors. But, I don't think that amplification would be the answer if they were asking about a triple negative cancer.
+1
tallerthanmymom
Also this is on page 632 of FA 2018 for those using that version
+
drzed
I can understand why @tulsigabbard dropped out of the race--she's taking step 1 soon LOL
+3
methylased
Young child following URI with TCP is pretty classic ITP. Sometimes they throw in extra stuff on purpose, but I didnโt see much on the bone marrow aspirate either.
+9
mousie
I was also thinking ITP but the bone marrow image kind of threw me off too, not sure what I'm supposed to see but still think ITP is best choice ...
+
meningitis
It also almost threw me off, but then I remembered he had low platelet count and I guessed those multinucleated cells were Megakaryocytes (I looked for Megakaryocyte Bone Marrow Biopsy in google and they are the same).
+1
what
Bone marrow shows increased megakaryocytes -> ITP
+
meningitis
I chose Testosterone but I almost chose GnRH because it is surged when starting puberty and therefore increases everything downstream.
+11
temmy
When answering the question, i thought to myself that if GnRH is correct, LH will be too cos GnRH stimulates the Leydig cells via LH to release testosterone. That left testosterone as the best answer because it had the most direct effect.
+11
goaiable
GnRH and LH are increased in a pulsatile fashion at the onset of puberty, so idk if that constitutes as the "rapid increase" that this question is asking for. Tripped me up also.
+
tallerthanmymom
I originally eliminated testosterone and chose androstanediol because women can have Acne Vulgaris too, and Testosterone should not be rising to the same degree. Do I not understand how puberty works?
+2
drzed
Women can still make testosterone though; and androstAnediOL is not the same as androstEnediONE
+3
meningitis
Could you elaborate? Is this related to: less "preload" from mother circulation causes lowered HR?
+
meningitis
Or backflow of blood and causes a Reflex Bradycardia? still confused on this question.
+
kentuckyfan
So I think the subtle difference in choice E is that there would be a negative CHRONOTROPIC effect, no inotropic effect (contractility).
+10
maxillarythirdmolar
if anything, inotrophy could go UP not down as diastole prolongs and LVEDV increases --> Starling equation bullshit
+
meningitis
Forgot the time frame for Serum sickness and got it wrong.. thanks @thomasalterman
+25
medstudent22
Taking it one step further - B-cell depletion = decreased Ab secretion = decreased opsonization.
Opsonization with subsequent phagocytosis by spleen = #1 mechanism by which encapsulated bacteria (ie Strep Pneumo) are degraded.
+3
meningitis
I think its there.. I thought it was the lighter red/pink material (hyaline material)
And I thought the white streaks were the fibrosis like "streaked ovaries"in Turners.
+
samadmom
Apparently the histology looks like leydig cell hyperplasia but is actually called "pseudoademonatous clusters" and are reduced in number due to increased FSH and LH.
+
meningitis
sorry about the formatting, they were supposed to be bullets not italic.
+30
drdoom
looks good to me! ;) instead of asterisks try using the plus sign for unordered lists; the system gets confused sometimes because the asterisk is also for italics ๐
+2
meningitis
Yeah, I noticed :s
Oh, I didnt know the + sign did that! Very much appreciated, I will try that next time.
+1
meningitis
and explains the flame hemorrhages (Goljan) caused by malignant HTN
+5
ally123
The flame hemmorhages are also a good buzz word for recognizing he has hypertensive retinopathy 2e chronic, uncontrolled HTN. Pt's with hypertensive retinopathy can also present with "cotton wool spots" and "macular star". Pics on FA 2019, p. 299
+2
madamestep
@ally123 I think the best buzzword for hypertensive retinopathy here is "190/135 mmHg"
+
meningitis
Also explains the splenomegaly. If you have thrombosed splenic vein, the blood will pool in the spleen, can also cause expansion of red pulp of spleen.
+11
pg32
I picked splenic vein because of this ^^ association. However, why is the patient vomiting blood if there isn't a backup of blood into the left gastric/esophageal veinous system?
+1
savethewhales
The splenic vein drains the fundus of the stomach. So, splenic vein thrombosis can cause gastric fundal varices, which explains his bloody vomit.
+4
ac3
@medschooler1 Just my guess, but when answering this I assumed that splenomegaly meant splenic congestion with blood which can only happen if its outflow tract (splenic vein) is blocked.
+5
thrawn
Arterial occlusion would be mesenteric angina - or the likes thereof. Venous occlusion leads to variceal bleed
+
imgdoc
You rule out arteries because if they are occluded its an infarction and if they are partially occluded you'll get angina.
+
meningitis
"Pick your **Big** **Foamie** **Zeibra** nose with your Sphinger"
Choose options with the letter I.
SpIngomyelin, Sphingomyelinase, bIgorgans (hepatomegaly etc), zeIbra bodies, Foam cells
+2
meningitis
isn't letter C the intercalated disc where the gap junctions are?
+13
chediakhigashi
The actin is bound to structural proteins at the Z-line, this was on u-world #1734 if i understood correctly
+
meningitis
More like Zika Virus (Same a. aegypti vector) since it says she has rash associated to her bone and muscle pain. I had Zika one time (i live in Puerto Rico).
Remember also dengue and Zika are Flavivirus. Dengue can cause hemolysis (hemorrhagic), and Zika is associated with Guillen Barre and fetal abnormalities.
+12
nala_ula
I'm shocked that I found a fellow puerto rican on this site! Good luck on your test!
+2
namira
dont be shocked! me too! exito!
+2
dr_jan_itor
I was thinking that its Murine typhus transmitted by fleas
+
monique
I would say this is more likely scenario of either Dengue or Chikungunya, not Zika virus. Excruciating pain is common in those, not in Zika. Zika has milder symptoms of those three infection.
+2
jakeperalta
Can confirm that Chikungunya's arthralgia is pretty horrible, from personal experience.
+
almondbreeze
UW: co-infection with chikungunya virus with dengue virus can occure bc Aedes mosquito is a vector of both Chiungunya, dengue, and zika
+
lovebug
FA2019, page 167 RNA virusesy.
+
lovebug
Found that Chikungunya also have Rash./// An erythematous macular or maculopapular rash usually appears in the first 2โ3 days of the illness and subsides within 7โ10 days. It can be patchy or diffuse on the face, trunk and limbs. It is typically asymptomatic but may be pruritic (Taubitz W, Cramer JP, Kapaun A, et al. Chikungunya fever in travelers: clinical presentation and course. Clin Infect Dis. 2007; 45: e1. )
+1
beto
it is chikungunya->fever, polyarthralgia, diffuse macular rash, dengue has retro-orbital pain mostly
+1
dr.xx
likely not "lil b" as 2-4 times as many cases are found in whites than in persons of other races
+7
drdoom
lil b not a referent of race; cf. lil boo, lil baybay, lil bowow, &c.
+
dr.xx
I disagree. Google "lil b" for images. See what you may discover.
+1
masonkingcobra
My issue was the stem said no skin damage (I would think pulling out your hair damages your scalp)
[Turns out it does not](http://onlinelibrary.wiley.com/doi/full/10.1111/j.1529-8019.2008.00165.x)
+
meningitis
Compulsively pulling out oneโs own hair. Causes significant distress and persists despite attempts to
stop. Presents with areas of thinning hair or baldness on any area of the body, most commonly the
scalp. Incidence highest in childhood but spans all ages. Treatment: psychotherapy is first line;
medications (eg, clomipramine) may be considered.
+15
teepot123
damn its in FA and Ive never ocne read it XO
+
hungrybox
be honest did u know that before looking it up
+9
meningitis
@hungry, because you didn't know it, doesn't mean he didn't. This is a forum for answering questions and helping out, not dissing or showing off. Grow up before becoming a doctor.
+32
sbryant6
Looks like somebody needs an enema to get that stick out.
+1
meningitis
SAD PUCKER:
Suprarenal (adrenal) glands [not shown]
Aorta and IVC
Duodenum (2nd through 4th parts)
Pancreas (except tail)
Ureters
Colon (descending and ascending)
Kidneys
Esophagus (thoracic portion)
Rectum (partially)
+25
cienfuegos
I find "SAID PUCKER" to be helpful because it includes IVC
+5
meningitis
I think you meant:
Jugular venous distention = LT HF
Pulmonary edema = RT HF
+4
hungrybox
woops yea I meant Jugular venous distention = RIGHT HF, Pulmonary edema = LEFT HF
+12
jackie_chan
What threw me off the picking 4-chamber dilatation was it seemed like that would be a major cardiac/ventricular remodeling and the vignette gave a somewhat acute 2 week onset
+
meningitis
Why isnt it endometriosis? Could someone help me out on this?
+2
meningitis
Sorry, I was confusing with higher risk for endometrial carcinoma.
+1
vi_capsule
Estrogen is responsible for cyclical bleeding and pain associated with endometriosis hence progestin is a treatment modality. But estrogen isnt a risk factor for Endometriosis. Rather theres retrograde flow, metaplatic transformation etc theories are responsible for endometriosis.
+1
sympathetikey
Tfw you get so thrown off by a picture that you don't read the question properly.
+34
hyperfukus
@meningitis idk if u still care lol but always go back to endometriosis=ectopic endometrial tissue outside of the uterus so you can rule it out since increased estrogen would cause you to have worsened endometriosis or a thicker one but not directly...you can see the clumps of the follicles in the ovaries if you look super close so that along with the presentation takes you to PCOS and anytime you don't have a baby or stay in the proliferative phase(estrogen phase) you get endometrial proliferation-->hyperplasia--->ultimately carcinoma
+2
lovebug
Other answer H)Meigs syndrome :
triad of 1) ovarian fibroma, 2) ascites, 3) pleural effusion. โPullingโ sensation in groin. FA 2019, pg 632
+1
xw1984
Isn't option G, Leiomyomata uteri, associated with high estrogen level? Per FA 2020, fibroid is estrogen sensitive.
+2
ownersucks
@xw1984 gross image would show multiple whorled masses
+1
meningitis
Why isnt it endometriosis? Could someone help me out on this?
+2
meningitis
Sorry, I was confusing with higher risk for endometrial carcinoma.
+1
vi_capsule
Estrogen is responsible for cyclical bleeding and pain associated with endometriosis hence progestin is a treatment modality. But estrogen isnt a risk factor for Endometriosis. Rather theres retrograde flow, metaplatic transformation etc theories are responsible for endometriosis.
+1
sympathetikey
Tfw you get so thrown off by a picture that you don't read the question properly.
+34
hyperfukus
@meningitis idk if u still care lol but always go back to endometriosis=ectopic endometrial tissue outside of the uterus so you can rule it out since increased estrogen would cause you to have worsened endometriosis or a thicker one but not directly...you can see the clumps of the follicles in the ovaries if you look super close so that along with the presentation takes you to PCOS and anytime you don't have a baby or stay in the proliferative phase(estrogen phase) you get endometrial proliferation-->hyperplasia--->ultimately carcinoma
+2
lovebug
Other answer H)Meigs syndrome :
triad of 1) ovarian fibroma, 2) ascites, 3) pleural effusion. โPullingโ sensation in groin. FA 2019, pg 632
+1
xw1984
Isn't option G, Leiomyomata uteri, associated with high estrogen level? Per FA 2020, fibroid is estrogen sensitive.
+2
ownersucks
@xw1984 gross image would show multiple whorled masses
+1
meningitis
Why cant it be protoporphyrinogen oxidase?
It was because of that reason (Increased AST and ALT) I thought it wasnt uroporphyrinogen decarb. My train of thought was: "wow, mitochondria are messed up.. there must be a lot of intermediates in there,therefore the Uroporph decarb must OK."
+
arlenieeweenie
FA 2019 pg. 417, the later on the defect in the heme synthesis pathway is the one more associated with skin findings! Also according to this year's edition uroporphyrinogen synthase is now known as prophobilinogen deaminase
+9
nobody
AMBOSS has estrogen therapy listed as a susceptibility factor for PCT. I could not find a link between elevated AST/ALT and estrogen therapy that would occur 15 years into treatment.
+
jcrll
I think it's about adding our opinion and more about seeing what the situation is because a patient contacted you in distress. The others are about contacting management off hearsay; that could also "muddy the waters," I Is this question also addressing quaternary prevention?
+3
meningitis
I agree with jcrll.
My same thought process but then I changed it to psychiatric consultation in order to first attend the patient's distress and anxiety since it was hindering her decision making.
Besides, the whole ordeal about her treatments and ineffectiveness was emotionally and physically exhausting her.
+4
tsl19
Going straight to the chair of the ethics committee without having spoken to the other physicians would be inappropriate because it would be jumping a bunch of steps in communication first - like jcrll said, you want to get the picture of what's going on from the other physicians first. Maybe the gynecologic oncologist isn't actually as opposed to palliative measures as the patient perceives him to be and thinks he's doing what the patient wants, etc. It could just be miscommunication, which you could help clear up without getting ethics involved ... better to start there.
+12
an_improved_me
Also, to add a little bit: internists on a healthcare team are the care coordinators. For any given problem a patient has, the internist is responsible for managing all the different aspects of a patients treatment. In this case, the intern has to manage the dissenting opinions of her different gynecologists. In other instances, an internist may have to manage the disagreement between a Surgeon vs. IR vs. Onc.
+2
meningitis
The above explanation is correct (disregarding the hard to read and unprofessional dialect) but just in case anyone was wondering:
chromatin-negative= Just a quick way of knowing it was a boy. The term applies to the nuclei of cells in normal males as well as those in individuals with certain chromosomal abnormalities
+17
yotsubato
Turner syndrome patients are also chromatin negative as well though....
+6
sympathetikey
I didn't know a complication post-meningitis was lack of humor.
+6
sympathetikey
Ah, didn't read the last line. Yeah, that is taking it a bit far
+32
niboonsh
yall are haters. this is the first explanation that has ever made sense to me
+7
whoissaad
How does chormatin-negative indicate a normal cell? Isn't chormatin just condensed DNA?
+2
cienfuegos
According to this paper most individuals with Turner Syndrome are chromatin negative: "One of the initial laboratory procedures used to confirm or rule out this diagnosis involves a sex chromatin determination from a buccal smear. Cells from the lining of the mouth are stained for the presence or absence of X-chromatin or Barr bodies, which represent a portion of an inactivated X chromosome. The typical Turnerโs syndrome patient, who has 45 chromosomes and only one sex chromosome (an X), has no Barr bodies and is, therefore, X-chromatin negative.
This abnormal X-chromatin negative finding in the majority of Turnerโs syndrome females is similar to the result found in a normal male, who also has only one X chromosome, and differs from the X-chromatin positive condition observed in the normal female, who has two X chromosomes. Occasionally, the patient with features of Turnerโs syndrome is found to be X-chromatin positive."
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6233891/
+2
hyperfukus
i really hate haters this is awesome!
+2
selectuw
to add to the above, free testosterone is aromatized to estrogen leading to breast development
+1
misrao
Is the free testosterone not creating male internal or external gentalia because of the defect in androgen receptors?
+1
hungrybox
jesus this answer was probably too long i'm sorry
+9
meningitis
I disagree. It's the complete thought process needed for many Thiazide/Loop question that can be thrown. Thanks.
+17
amirmullick3
This is what NBME should be providing with each question's correct answer! Thanks hungrybox!
+1
amirmullick3
@hungrybox did you mean "All of this DECREASED Na increases aldosterone activity."?
+2
pg32
Anyone care to explain why she feels she has, "lost [her] pep"? Is that due to the hypokalemia? Or hypercalcemia caused by the thiazides?
+
cmun777
@madojo @pg32 I assumed between her hypokalemia (which can cause weakness/fatigue) and possible contraction alkalosis those were the most likely causes for the "lost her pep" comment. I think if they wanted to indicate hypercalcemia to differentiate if loop diuretics were also in the answer choices they would certainly give more context for hypercalcemia sx
+
meningitis
Does anyone know the relevance of the stem saying: "during this time she also has been crying frequently"?
+53
usmleuser007
Think the postrenal azotemia is d/t her pregnancy. With the increasing in size fetus, the pelvic cavity is being compressed and thus there is pressure on the ureters. This leading to the presentation.
As per above --- the crying maybe just d/t her pain and emotional stress caused by worrying about possible complications regarding her fetus.
+4
maxillarythirdmolar
My gut tells me it must be some sort of transient change in placental size with hormonal changes. It's reminiscent of what you might expect for breast changes during the menstrual cycle, imo
+
j44n
or maybe the fetus is literally crushing her ureters into the wall of her pelvis and shes got an infected kidney
+4
meningitis
I found this to add a little bit more explanation as to how it causes the acidosis if anyone needs it.
1. Mitochondrial toxicity - decreases aerobic respiration and shunts to lactic acid production
2. Cardio toxicity (Secondary to Mitochondrial toxicity) leads to cardiogenic shock (hypoperfusion), which causes lactic acidosis
3. Hepatotoxicity - Decreases lactate metabolism, causing lactic acidosis
4. When in trivalent form (Fe+3), it can react with 3 molecules of H2O
--> FeOH3 + 3H+
This will then deplete Bicarb buffering system resulting in non-gap acidosis.
Source: https://forums.studentdoctor.net/threads/iron-poisoning-anion-gap-or-non-anion-gap-acidosis.958285/
+20
sympathetikey
None of the other choices were even metabolic acidosis. They threw us a bone with this one.
+33
imnotarobotbut
Don't changes in bicarb take a few days? How did his bicarb drop down to 8 in 12 hours?
+2
j44n
they did throw us a bone however I didnt catch it
+7
meningitis
Yes, correct. The 5'GGCC option could cause some confusion.
+1
guillo12
I really don't understand the question nor the answer. Can someone explain it for dummies like me?
+16
whossayin
yes please.. I'm with guillo12 on this
+
sugaplum
@guillo12 @whossayin
questions says you've created a new cut site,
1. look at the region on the sick vs healthy. The C to G is the change
2. Write out the sick "CCGG" from 5'3'- you could write out the whole thing, but the answer only has 4 letters, so being lazy here
3. write under it, its complement, the dna base pair. So "GGCC"
4. remember both strands are going in opposite directions when you write them out on top of each other.
5. So the bottom strand actually reads 5' CCGG 3' so that is the answer
I hope that clears it up
+60
shirafune
To add to the palindrome part, many restriction endonucleases actually function as dimers. Each individual subunit usually has a nickase, so to create a double-stranded break in DNA, they must bind a palindrome so that each enzymatic domain creates a single-stranded break (thus a double-stranded break).
+1
alimd
Why do we start from CCGG? Why not CGGG or TACC?
+6
alimd
Why do we start from CCGG? Why not CGGG or TACC?
+1
ssbhatti
I think its due to the palindrome requirement?
+
bbr
Maybe I'm missing a part here, but the substrate that the enzyme will bind to will be the DNA. I went with the line that was from the questions stem, as it is the mtuated DNA will be recognized by the restriction enzyme. I didnt see the need to convert it into base pairing. Let me know what you guys think.
+2
uloveboobs
@bbr I agree. I'm definitely not an expert in these lab tests, but the question asks "substrate specificity." I was thinking that it would recognize the abnormal DNA; nothing to do with RNA. I didn't know about the palindromic preference of restriction enzymes, but I don't think there's any need to figure out base-pairing and whatnot here. (At least for this question it didn't work out that way!)
+
spaceboy98
sugaplum, I'd give you an award if this was Reddit
+6
The question is confusing because a TRUE POSITIVE test result is finding detecting cancer by US (goes to show you we gotta look at what the test is looking for).
An ABNORMAL test detecting PrCa means its NOT A POSITIVE: ie: 35 out of 50 were False Positives
An ABNORMAL test WITHOUT PrCa means its NOT A NEGATIVE: 20 out of 100 WITHOUT PrCa were FALSE NEGATIVE.
TN = 80, FP = 15. Specificity: TN/(TN+FP); 80/(80+15) = 84%. And since it says "best represents" then 84% is closest to 80%.