step1 Bioch.

[IMG SURVIVOR]

A 22 year old African-American male presents to the family physician office for bloating, flatulence, abdominal cramps and explosive watery diarrhea following ingestion of dairy products.

. Physical examination reveals abdominal distension and borborygmi. You decide to investigate the patient further. Which of the following test result is most likely to be observed?





A Positive Clinitest of stool for oxidizing substances

B Decreased stool osmotic gap

C Positive hydrogen breath test

D Alkaline stool pH

[IMG SURVIVOR]

no one????????????????????????

[Dr. X]

i "c" what the problem is.. it appears that he may have lactose intolerance which would definitely be the first in the differential list hence you would do the hydrogen breath test to rule it out. my one eyebrow is going up however since he's 22 and LI could've been detected much earlier in his life.. (history could help) and there on, i would think about micro tests for possible food poisoning.. etc etc.

[MDTOB]

i "c" what the problem is.. it appears that he may have lactose intolerance which would definitely be the first in the differential list hence you would do the hydrogen breath test to rule it out. my one eyebrow is going up however since he's 22 and LI could've been detected much earlier in his life.. (history could help) and there on, i would think about micro tests for possible food poisoning.. etc etc.


Classic case of lactase deficiency. Can be acquired even later in life. Most commonly seen in Asians. Not necessarily congenital. Hydrogen breath test = Dx!

[IMG SURVIVOR]

MDTOB you are doing very good men. keep it up