Fecal Occult Blood Testing for Iron Deficiency: A Reappraisal

Abstract

Fecal occult blood (FOB) tests have been evaluated primarily for the application of colorectal cancer screening. Less is known about the performance characteristics of FOB tests for the evaluation of iron deficiency, the most common other application. As most clinically important occult gastrointestinal bleeding arises from the proximal gut, it is critical that FOB tests target analytes that are stable during the enteric transit. Available data indicate that guaiac-type and immunochemical tests are insensitive for the detection of proximal gut bleeding, and their use may confound the evaluation of iron deficiency. In contrast, the heme porphyrin test is sensitive for both proximal and distal sources of occult gastrointestinal bleeding, and this FOB test would appear to be the most rational selection for use in patients with iron deficiency or anemia. Outcome data are needed to better assess the impact of FOB testing on algorithms for evaluation of iron deficiency.

Fecal metabolomic profiles: A comparative study of patients with colorectal cancer vs adenomatous polyps

“…From the above analyses we can conclude that both low and high molecular weight molecules, visible using the 1D NOESY pulse sequence, are important to characterize at metabolic level the two pathological profiles. Moreover, the capability to accurately predict HCs when compared to patients with colonic AP or adenomas and CRC patients (showed predictive accuracy of 85.3%) using 1 H-NMR fecal water spectra, could be tested on a larger number of subjects to develop fast screening following a positive fecal occult blood test in order to spare colonoscopy in some patients who have bleeding due to other reasons[ 38 , 39 ].…”

Colorectal Cancer in Pregnant Woman

“…In the onset of symptoms, it is important to locate the tumor, its dimensions, degree of invasion Cancer of the right colon are generally bulky, ulcerated, with an important sclerolipomatous peritumoral process, which is why they often appear to be more advanced than they actually are, hemorrhagic, usually with small but chronic bleeding, leading to unexplained anemia. Due to the minimal bleeding, the appearance is occult bleeding, and can only be detected by specific tests [16,88].…”