•A 55 y/o man presents with shortness of breath on exertion. Laboratory studies reveal iron deficiency anemia. Patient was started on Iron pills orally. The patient consumes a lot of red meat and was surprised to know that he was iron deficient. Fecal occult blood testing revealed a positive stool guaic. A colonoscopy and EGD were subsequently performed which were absolutely normal. A repeat Guaic was performed and was found to be negative. A further investigation for the cause of iron deficiency in this patient revealed celiac disease leading to iron malabsorption. What is the most likely cause of positive Guaic in this patient? •
A. Obscure GI Bleeding
B. Celiac disease
C. False positive from red meat
D. False positive from Iron pills
E. Colon cancer
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I think its C. false positive from Red meat (coz the blood from the meat might be making the test +), but not sure.
May be even obscure GI bleeding, which could be from the small intestines which are not detected by routine colonoscopy and EGD scopy.
Colon cancer is ruled out by colonoscopy, Iron pills do not cause false positive stool guaic. celiac disease majorly causes malabsorption and not bleeding from the GI tract.
false positive result with iron.
i think false positive with red meat. but z he off the red meat next time he z having the test?
I think its c
Most probably C
A
actually both iron &red meat can cause false positive guaiac
c for sure.
iron therapy
question is wrong
Most probably C
hahahaha, bhutaa plz idher ye kaam naaa kar
A “false-positive” guaic test is a test result when there is in fact no source of bleeding. This can occur if the recommended dietary instructions are not followed before Guaic. For example; the heme in red meat or the peroxidase or catalase activity in vegetables, especially if uncooked, can cause analytical false positives.
This patient has all the work up done and there is alternative etiology to explain his iron deficiency. Hence, obscure bleeding is less likely and this result is probably, a false positive from excess red meat.