DIAGNOSTIC-TESTS IN GASTROINTESTINAL INFECTIONS

Progress has been made in the past year in the development of new or improved diagnostic techniques based on the use of monoclonal antibodies, DNA probes, and the polymerase chain reaction (PCR). In this review, emphasis is placed on new rapid tests that can be incorporated into the work flow of the clinical laboratory. In addition, promising new PCR-based technologies are described that are aimed at the rapid detection of specific genetic sequences harbored by a variety of infectious agents. In all, 19 new PCR tests are described that target toxin genes of Clostridium difficile, enterotoxigenic Escherichia coli, enterohemorrhagic E. coli, virulence genes of Shigella, enteroinvasive E. coli, Yersinia, Entamoeba histolytica, and the urease gene of Helicobacter pylori. PCR tests for enteric adenoviruses and rotaviruses of groups A, B, and C are also described. All procedures are critically reviewed for levels of sensitivity, specificity, and impact on the diagnosis of enteric infectious diseases.