infectious disease question

[arthrodisiac]

Advertisement - Members don't see this ad

is it possible to have cmv esophagitis with a cd4 of 90?...thought u had to be below 50.

 

[Hard24Get]

is it possible to have cmv esophagitis with a cd4 of 90?...thought u had to be below 50.

In most cases the patient's CD4 count is 50 or less, but that is used as more of a "consider prophylaxis" point than a sine qua non - in fact, in at least one study patients with CD4 counts of less than 100 were just as likely to get CMV disease as those with counts of 50..

I like to think of CD4 cells (and really all immune cells) as little people. You can estimate you need a police force of 50 to keep a certain town under control, but every now and again things get out of hand even with double that amount. It also depends on the quality of the force - I could easily imagine certain HLAs as being more or less susceptible to CMV infection, for instance...

 

[Tired]

In most cases the patient's CD4 count is 50 or less, but that is used as more of a "consider prophylaxis" point than a sine qua non - in fact, in at least one study patients with CD4 counts of less than 100 were just as likely to get CMV disease as those with counts of 50..

I like to think of CD4 cells (and really all immune cells) as little people. You can estimate you need a police force of 50 to keep a certain town under control, but every now and again things get out of hand even with double that amount. It also depends on the quality of the force - I could easily imagine certain HLAs as being more or less susceptible to CMV infection, for instance...

I like your answer, although I think the HLA supposition is a bit of a stretch at this point.

The issue is, as you point out, the "50" number is a general cutoff, not a hard & fast rule. Think of it this way: 90 or 50, either way you're f*cked.

 

[Hard24Get]

I like your answer, although I think the HLA supposition is a bit of a stretch at this point.

The issue is, as you point out, the "50" number is a general cutoff, not a hard & fast rule. Think of it this way: 90 or 50, either way you're f*cked.

Eh? Why? Besides, I said imagine. Truth be told, I can imagine alot more than that - all types of cells and proteins, such as interferons, are involved in immunity to CMV. A defect in any one of them could shift the balance of susceptibility to disease. The immune system is as delicate as it is complex...😍

 

[arthrodisiac]

i understand that in real life cutoffs don't apply...but the reason i brought it up was because there was a usmleworld question with cd4 90 and cmv esophagitis was the diagnosis...which seemed like bs to me, cuz exams are supposed to be clear cut in definitions for things, otherwise how the hell are you supposed to know when the rules do and dont apply.

 

[Hard24Get]

i understand that in real life cutoffs don't apply...but the reason i brought it up was because there was a usmleworld question with cd4 90 and cmv esophagitis was the diagnosis...which seemed like bs to me, cuz exams are supposed to be clear cut in definitions for things, otherwise how the hell are you supposed to know when the rules do and dont apply.

Well, maybe the clinical scenario matched the best - in that case, hard and fast rules should be abandoned. Besides, I think 100 is a more reasonable "guideline" for thinking about it. Why don't you share the question? It is always fun to surreptitiously learn while hangin' out on SDN. 🙂

 

[arthrodisiac]

42 year old male with aids for 1 year. 2 week history of very painful and difficulty swallowing which fails to respond to oral fluconazole. Pain is substernal and burning. CD4 is 90 and viral count is 300,000. He is taking Z-L-I and bactrim. Large irregular shallow ulcers in upper third of esophagus. Biopsy shows tissue destruction and inclusions. Most appropriate next step:

1- oral prednisolone
2- oral acyclovir
3- IV ganciclovir
4- IV foscarnet
5- oral itraconazole



I realize its inclusions, large ulcers which is cmv....but still pisses me off they say 90 when all the books make us memorize 50. i ruled it out with that and put acyclovir. maybe im just an idiot. in retrospect...would probably be IV acyclovir anyway, not oral.

 

[Tired]

I feel like an idiot, because I should have read the thread starter closer.

1) The cutoff for CMV esophagitis is 100, not 50 (I double-checked this on emedicine). The "50" you are thinking of is the cutoff you use for initiating gangcicylovir prophylaxis.

2) Acyclovir = HSV, gangcicyclovir = CMV.