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A 62 y.o. man presents to his physician for an annual check up. He has felt well, and has no complaints. He denies fever, weight loss, fatigue, night sweats, diarrhea, or constipation. He has noticed no bleeding or bruising. His past medical history is notable for hypertension, for which he takes hydrochlorothiazide. He also takes Vit. C. He denies alcohol or tobacco use. His typical diet includes steak approximately 3 times per week.. His weight has not changed from his last visit. His BP is 133/83 and HR 77bpm. Head and neck examination demonstrates no lymphadenopathy or carotid bruits. Chest is clear to auscultation , and he has no abnormal heart sounds. His abdomen is soft, without hepatosplenomegaly. Peripheral examination reveals no clubbing, cyanosis or edema. Rectal exam reveals a minimally enlarged smooth prostate. The stool is brown and is guaiac positive. Last colonoscopy was 2 years ago and was unremarkable.

What is the next step in the management of this patient?

a) Barium enema

b) Check the hematocrit

c) Reassurance , as the hemoccult -positive stool is likely secondary to red- meat consumption

d) Repeat fecal occult blood testing in 2 weeks

e) Colonoscopy


do a colonoscopy......


FOBT positivity warrants a colonoscopy.

'c' option would have been right if he had recently started consuming red meat but in the question stem thats his regular diet.


1st v hav to rule UGI causes. that option not given. E?? think not rt ans. as its tricky q. lets c.


actually answer can be" repeat FOBT in 2 weeks" after putting the patient off red meat.

now am confusedsticking out tongue


Nice q jean..thanks..
The stem put 2 important points:red meat(steak) that gives False+ and VitC that gives F- in guiac..
so I think we can presume that he has guiac+,
but I'm not sure that whether with just one FOB+ we proceed colonoscopy or not??
I go with e, but Im not sure...




For a simple, traditional test, foods to avoid include red meat (the blood it contains can turn the test positive), radishes, turnips, cabbage, cauliflower, horseradish, uncooked broccoli, and cantaloupe (all of which contain a chemical with peroxidase properties that can turn the test positive), and citrus fruits and vitamin C supplements (which can turn the test falsely negative).---from wiki

This pt appears healthy. So repeat test seems right. IF he has s/s, then colonoscopy is warrented.


Dear threewalkers,
please read my answer, I thought like you ... but despite the fact that he has a one false+ and one F- in his diet, his FOB test turn positive..why did you interpret the test normal?


any positive FOB, warrants Colonoscopy, even it is 1 day after last colonoscopy.

even if in 3 FOB, the 2nd comes positive followed by 3rd one which is negative, you still need to do colonoscopy.

and people with cancers specially GI cancers are symptomatic only in advanced cases.


i think its e) colonoscopy and as far a hematocrit is concerned i dont think it will give us more info than v already know i.e hez losing blood in sool so must b having low hematocrit, neither will it bring us a step closer to diagnosing him.
since the stem asks next step in managment and the guy hasnt had clonoscopy since 2 yrs at this age it should be colonoscopy first .


jean, wats rt ans??? pls explain,


bahar_1982 wrote:
Dear threewalkers,
please read my answer, I thought like you ... but despite the fact that he has a one false+ and one F- in his diet, his FOB test turn positive..why did you interpret the test normal?

Hi, Bahar, we don't know if Vc negates red meat. It is easy and uninvasive and fast to repeat the stool test then to do the invasive colonoscopy, which He had 2 years ago. Besides, he is healthy and no s/s. We want to make sure that he really had + SOFB before any invasive test.


je crois que c'est B.


Well done, guys. Nice discussion.

Correct Answer is B.

This patient has positive fecal occult blood test without symptomatology. While this may be result of the patient s diet (red meat and vit C), not working up this result further may miss a significant underlying lesion. The first step in management is to establish how much blood is being lost , if any, and whether this is hemodynamically significant blood loss. Based on his normal HR and BP, it s unlikely that the patient is having a significant daily blood loss.

However , chronic GI blood loss can depress the hematocrit significantly and there is no cutoff for symptomatic anemia. The "threshold" for patients with anemia to become significant is usually based on a combination of factors, including increasing age and other comorbid conditions.


Colonoscopy is likely going to be a part of this patient s workup;however it should be performed after is hematocrit obtained.

Repeat fecal occult testing is not appropriate , as just a single positive result needs to be worked up and explained.


great bleed q of colon. tq jean.


Thanks for the q jean robert...
threewalkers..thanks for the were right..


my mom answered this question grin like literally!


Let's analyze and re-phrase the learning objective of this question :
Always check the Hematocrit when there is (+) FOBT , and if Hematocrit is low, then do colonoscopy . Sounds logical.
But what if hematocrit is normal ? what is the next step ?

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