Background. Test of occult fecal blood loss belongs to the basic diagnostic procedures in gastroenterology. That examination is introductory method for screening, diagnosis and dispensarization of patients with colorectal cancer. Most frequently used tests in practice are biochemical and immunochemical tests. The aim of the study was to compare the results and clinical contribution of both kinds of tests. Methods and Results. The results of immunochemical test Immocare (Care Diagnostica) and biochemical test Haemoccult (Röhm Pharma) were compared in a group of 253 patients (131 women, 122 men, average age 52,6 yr, range 19–88 yr). In all patients total coloscopy was subsequently performed. Sensitivity of immunochemical test was clearly higher (61,2 %) than of biochemical test (29,4 %), specificity was slight lower (95 %, resp. 98 %). Accuracy of Immocare test was also higher (82 % than 72 % of Haemoccult). Conclusions. Our results confirm advantages and competency of Haemoccult test for screening and dis pensary programmes. More expensive and more difficult Immocare test is suitable for examination of symptomatic or risk patients.

        Key words: Occult Fecal Blood Loss, Haemoccult test, Immocare test, coloscopy, colorectal carcinoma, screening.