Sensitized immunochemical method for the specific detection of human haemoglobin in dried biological samples

Early detection for colorectal cancer: new aspects in fecal occult blood screening

The authors report on promising diagnostic methods of occult intestinal bleeding and discusses the potential new strategy of early detection of colorectal carcinomas in respect to old and new diagnostic measures available. Because of the limited sensitivity and specificity of classical methods used for the demonstration of occult fecal blood, the authors recommend the introduction of new techniques and markers in screening practice. It is presumed that new discoveries in molecular biology will improve the accuracy of early colorectal cancer prevention. Their implementation into routine screening, however, will not take place in the near future. Until their realization, improved screening efficacy is expected from the use of more specific and sensitive blood tests.

Laboratory study on occult gastrointestinal bleedings: differential diagnostic method for the parallel study of intact and fragmented hemoglobin

The authors produced various degradation products of human hemoglobin. With the aid of immune sera raised against native hemoglobin and their fragments, we examined the antigenicity of the intact molecule and fragments as well as the specificity and reactivity of the immune sera used. Since conventional guaiac-type reactions make no distinction between the different hemoglobin molecules and the methods described in recent years' publications only with immune sera raised against native intact hemoglobin, the demonstration of occult fecal blood has not reached the desired rate of efficacy in clinical practice. The authors recommend the introduction of a simple differential diagnostic methods suitable for the parallel examination of intact and fragmented hemoglobin.

Double immunochemical screening test (hemoglobin and albumin) for the detection of occult intestinal bleeding

The authors have developed a combined electrophoretic-immunoprecipitation technique suitable for the simultaneous demonstration of two blood proteins, i.e., hemoglobin and albumin, in the feces. The analytical sensitivity of the method is 2 micrograms hemoglobin and albumin/ml. The technique is simple, inexpensive, and suitable for the reliable demonstration of occult intestinal bleeding for either inpatients or mass screening. This technique is an aid not only to the fact that bleeding can be detected, but to its intensity, as well. This new technique improves the diagnostic accuracy of early detection of carcinomas and polyps, presumably without raising significantly the number of "false-positive" reactions.