Official Similar mechanisms/presentation thread

[Transposony]

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There are many question where they give you the presentation followed by the diagnosis and then ask "Which of the following has similar mechanism" as the given condition.
I am starting this thread in the hope that we can bunch together these "similar mechanism" conditions to help us on the test.
I'll start:

Patient is having mucosal bleeding following percutaneous coronary intervention. Abciximab was give during this procedure. Which of the AR disorder has similar mechanism which led to bleeding in this patient?

 

[dfib slim]

Glanzmann's

 

[dfib slim]

A patient suffers from Gitelman syndrome. An overdose of which medication would most likely produce similar findings?

 

[Transposony]

Glanzmann's

Great, take the test already 🙂

Glanzmann's thrombasthenia is associated with abnormal glycoprotein IIb/IIIa which is an integrin aggregation receptor on platelets.

 

[dfib slim]

Just started uworld today. I'm diggin it.

 

[Transposony]

A patient suffers from Gitelman syndrome. An overdose of which medication would most likely produce similar findings?

Thiazides.

What about Bartter's syndrome ?

 

[dfib slim]

Lasix

 

[Transposony]

Bacterial toxin which has similar mechanism of action in humans as tetracycline in bacteria?

 

[faisal 2000]

Toxic which has similar mechanism of action in humans as tetracycline in bacteria?

psudomonas extoxin A--> liver
shiga toxin--> bloody diarrhea
diphtheria toxin --> heart

 

[madeyedhl]

Mother has hair growth etc during pregnancy. Baby girl also "virilized". Whats the disease? What drug with similar mechanism?

 

[dfib slim]

Mother has hair growth etc during pregnancy. Baby girl also "virilized". Whats the disease? What drug with similar mechanism?

11 Beta-hydroxylase deficiency, exogenous testosterone/danazol?

 

[madeyedhl]

11 Beta-hydroxylase deficiency, exogenous testosterone/danazol?

Should have been clearer or is this not enough info? Confused myself... +_+ I think it is enough info...

I was thinking of aromatase deficiency. 11 b hydroxylase deficiency would cause virilization of female, but would have added hypertension to the vignette maybe?
But wait... 11 b hydroxylase def would also have increased testosterone& estrogen--> why virilization? +_+ Just TOO much testosterone?

The hint I was trying to make was that mothers also get virilized during pregnancy in aromatase deficiency because infant's testo would pass placenta..

But, now what I don't get is.. 11 b hydroxylase also has increased testo AND estrogen (because it has normal aromatase), so why do those kids have virilization, can someone answer please? 🙂 Thanks.

 

[Transposony]

Which drug used to treat side effect of an anticancer agent has similar mechanism of action as a drug used to treat acetaminophen toxicity ?

 

[Transposony]

Name the conditions in which the actual damage is due to type IV hypersensitivity but can be diagnosed by antibodies ?

 

[dfib slim]

Name the conditions in which the actual damage is due to type IV hypersensitivity but can be diagnosed by antibodies ?

Celiac disease and pernicious anemia

 

[Transposony]

Celiac disease and pernicious anemia

I remember 4 more...........

 

[dfib slim]

I remember 4 more...........

I think T1DM and hashimotos?
Haven't had MSK or neuro systems yet so I'm missing a few.

 

[Apoplexy__]

Should have been clearer or is this not enough info? Confused myself... +_+ I think it is enough info...

I was thinking of aromatase deficiency. 11 b hydroxylase deficiency would cause virilization of female, but would have added hypertension to the vignette maybe?
But wait... 11 b hydroxylase def would also have increased testosterone& estrogen--> why virilization? +_+ Just TOO much testosterone?

The hint I was trying to make was that mothers also get virilized during pregnancy in aromatase deficiency because infant's testo would pass placenta..

But, now what I don't get is.. 11 b hydroxylase also has increased testo AND estrogen (because it has normal aromatase), so why do those kids have virilization, can someone answer please? 🙂 Thanks.

No, your vignette of aromatase deficiency is classical, and high-yield. I believe the drug you were going for was anastrazole.

I think what you're misunderstanding is that you're thinking in the vignette you gave that the fetus has aromatase deficiency. It does not. Your vignette is of a woman who has aromatase deficiency, which manifests/gets more apparent upon becoming pregnant. She gets hiruste/virile off the fetus's normal androgens. The fetus is fine; the mother has aromatase deficiency.

 

[Transposony]

I think T1DM and hashimotos?
Haven't had MSK or neuro systems yet so I'm missing a few.

The classical---> Rheumatoid arthritis.
Also, Guillain-Barre.

 

[Transposony]

Which drug used to treat side effect of an anticancer agent has similar mechanism of action as a drug used to treat acetaminophen toxicity ?

Well, I'll answer it :
MESNA has similar MOA as N-acetylcysteine.

 

[seminoma]

Well, I'll answer it :
MESNA has similar MOA as N-acetylcysteine.

Can you expand? I thought mesna inactivated acrolein and NAC was a precursor in glutathione synthesis.

 

[seminoma]

Presents like sarcoidosis, but the vignette mentions a specific employment or toxic exposure. Where does the guy work/what is the exposure and what is the diagnosis?

 

[dfib slim]

Can you expand? I thought mesna inactivated acrolein and NAC was a precursor in glutathione synthesis.

It's a sulfhydryl group mediated antioxidant.

 

[Transposony]

Presents like sarcoidosis, but the vignette mentions a specific employment or toxic exposure. Where does the guy work/what is the exposure and what is the diagnosis?

Berylliosis, associated with aerospace industry.

 

[Transposony]

Most common side effect of statins?

 

[faisal 2000]

Presents like sarcoidosis

in sarcoidosis there is Noncaseating granulomas as beryllium exposure, Crohn disease, and cat scratch disease.
sarcoidosis result in destuction of multiple organs most commonly lung ,salivary gland,and lacrimal gland . it looks like Sjogren syndrome but in
Sjogren syndrome there is no Noncaseating granulomas

 

[dfib slim]

Most common side effect of statins?

Fatigue, maybe a little myopathy.

 

[Transposony]

Fatigue, maybe a little myopathy.

Hepatotoxicity which is about 20 times more common than myopathy.
That's why baseline LFT are recommended before starting statins.

Edit: Myopathy is the most common side effect of statins.

 

[faisal 2000]

Which drug used to treat side effect of an anticancer agent has similar mechanism of action as a drug used to treat acetaminophen toxicity ?

if patient take Methotrexate and then start developing its side effects , folic acid supplementation is good choice to deal with that

 

[faisal 2000]

which condition has the same mutation in the adenomatous polyposis coli (APC) gene as familial polyposis ??

 

[seminoma]

Hepatotoxicity which is about 20 times more common than myopathy.
That's why baseline LFT are recommended before starting statins.

Myalgia is the MC side effect of statins. Hepatotoxicity might be more common than rhabdo, but it definitely isn't more common than myopathy, which includes myalgia.

 

[Transposony]

Myalgia is the MC side effect of statins. Hepatotoxicity might be more common than rhabdo, but it definitely isn't more common than myopathy, which includes myalgia.

Source/explanation ?
Also, why LFTs are recommended and not CPK ?
This is what FA 2015 Page 306 says: Hepatotoxicity ( increased LFTs), myopathy (esp. when used with fibrates or niacin).
AFAIK, Statins are the most common drugs that cause myopathy but the most common side effect of statins is hepatotoxicity.

 

[dfib slim]

Source/explanation ?
Also, why LFTs are recommended and not CPK ?
This is what FA 2015 Page 306 says: Hepatotoxicity ( increased LFTs), myopathy (esp. when used with fibrates or niacin).
AFAIK, Statins are the most common drugs that cause myopathy but the most common side effect of statins is hepatotoxicity.

From Uptodate

Statins-associated muscle adverse events are not uncommon. Myalgias and myopathy occur with a frequency of 2 to 11 percent. However, severe myonecrosis and clinical rhabdomyolysis are much rarer (0.5 percent and less than 0.1 percent, respectively). Patients can experience statin-induced myalgias without an elevation in serum creatine kinase (CK) concentration. (See 'Epidemiology' above.)

Hepatic dysfunction — Clinical studies of statins have demonstrated a 0.5 to 3.0 percent occurrence of persistent elevations in aminotransferases in patients receiving statins. This has primarily occurred during the first three months of therapy and is dose-dependent.

When I said myopathy, I was referring to myalgia, not rhabdo.

 

[seminoma]

Source/explanation ?
Also, why LFTs are recommended and not CPK ?
This is what FA 2015 Page 306 says: Hepatotoxicity ( increased LFTs), myopathy (esp. when used with fibrates or niacin).
AFAIK, Statins are the most common drugs that cause myopathy but the most common side effect of statins is hepatotoxicity.

Source is just that I remember learning it a few weeks ago. Took a look online just now and didn't find anything convincing on pubmed, although mayo does say myalgia is most common.

LFTs recommended for a couple of reasons (again no source, just what I learned). First, liver damage is more clinically silent and has worse outcomes than muscle damage. Second, CK can be normal in statin-myopathy so testing doesn't have great sensitivity.

 

[Transposony]

Uptodate trumps all. Wish I could afford a subscription.
I checked other resources and hepatotoxicity was a major side effect during initial post-marketing surveillance studies but later studies found myopathy to be the major side effect.
Interestingly, incidence of Statin hepatotoxicity is not increased in patients with chronic hepatitis C, hepatic steatosis, or other underlying liver diseases, and statins can be used safely in these patients.
Also, Statins (just like ACEls) are category X and must be discontinued before pregnancy.

Note on mechanism: Statins causes increased expression of the LDL receptor gene therby upregulating LDL receptors. The greater number of LDL receptors on the surface of hepatocytes results in increased removal of LDL from the blood, thereby lowering LDL-C levels.

 

[Silo004]

Name the conditions in which the actual damage is due to type IV hypersensitivity but can be diagnosed by antibodies ?

Goodpasture's??

Edit: Wrong, it's type 2 insensitivity.

 

[dfib slim]

Uptodate trumps all. Wish I could afford a subscription.
I checked other resources and hepatotoxicity was a major side effect during initial post-marketing surveillance studies but later studies found myopathy to be the major side effect.
Interestingly, incidence of Statin hepatotoxicity is not increased in patients with chronic hepatitis C, hepatic steatosis, or other underlying liver diseases, and statins can be used safely in these patients.
Also, Statins (just like ACEls) are category X and must be discontinued before pregnancy.

Note on mechanism: Statins causes increased expression of the LDL receptor gene therby upregulating LDL receptors. The greater number of LDL receptors on the surface of hepatocytes results in increased removal of LDL from the blood, thereby lowering LDL-C levels.

Your school doesn't give you free access?

 

[Transposony]

Your school doesn't give you free access?

My school only taketh........not giveth (esp anything free).

 

[seminoma]

My school only taketh........not giveth (esp anything free).

We must go to the same school.

 

[seminoma]

Name the conditions in which the actual damage is due to type IV hypersensitivity but can be diagnosed by antibodies ?

RA, some forms of acute transplant rejection, TB, lots of others I'd imagine.

 

[Transposony]

RA, some forms of acute transplant rejection, TB, lots of others I'd imagine.

Acute transplant rejection can only be diagnosed by biopsy.
Others are:
Celiac disease
Pernicious anemia
Type 1 DM
Hashimoto's
Guillain-Barre

 

[syoung]

offtopic
just took repro, so now i know what a seminoma is -_-

 

[CodeRedDew]

offtopic
just took repro, so now i know what a seminoma is -_-

yeah he has huge cajones

 

[Transposony]

offtopic
just took repro, so now i know what a seminoma is -_-

So, what's the equivalent in females especially common in a chromosomal disorder that affects only females?

 

[lunalight]

So, what's the equivalent in females especially common in a chromosomal disorder that affects only females?

Dysgerminoma, Turner's

 

[faisal 2000]

3 conditions not organisms cause watery diarrhea

 

[theTruth_97]

Bacterial toxin which has similar mechanism of action in humans as tetracycline in bacteria?

Could someone explain this one? I thought tetracyclines inhibited binding of amino-acyl tRNA to the 30S subunit?

 

[seminoma]

Could someone explain this one? I thought tetracyclines inhibited binding of amino-acyl tRNA to the 30S subunit?

And shigatoxin prevents binding of trna to eukaryote 60s. The adenine deletion results in inability to bind trna

 

[faisal 2000]

3 conditions not organisms cause watery diarrhea

1-vipoma --> watery diarrhea, hypokalemia, and achlorhydria
2- Collagenous colitis
3- lactose intolerance

 

[faisal 2000]

6 conditions cause increased bledding time