PCR FOR DETECTION AND CHARACTERIZATION OF PARASITES (LEISHMANIA, ECHINOCOCCUS, MICROSPORIDIA, GIARDIA)

The application of PCR for the diagnosis and the characterisation of p arasites is discussed using four examples. (1) A PCR assay that was de veloped for the detection of Leishmania was shown to be as highly sens itive as in vitro cultivation of the parasites from lymph node aspirat es and bone: marrow biopsies. (2) Single eggs of Echinococcus multiloc ularis can principally be detected and identified by PCR. However, a c umbersome sample preparation is inevitable in order to remove PCR-inhi bitory substances present in fox faeces. (3) Analysis of the amplified SSU rRNA gene of Encephalitozoon-like isolates from humans, rabbits a nd farm foxes confirmed for the first time that E. cuniculi-isolates f rom humans and animals are indistinguishable and that they are of impo rtance as opportunistic parasites in HIV-infected patients. (4) Swiss isolates of Giardia originating from humans, calves, sheep and a dog c ould be allocated into three distinct genetic groups by analysing seve ral PCR-amplified genes that encode for variant specific surface prote ins. There was no evidence for the presence of host-specific genotypes .