A nosocomial outbreak of Candida parapsilosis in southern Sweden verified by genotyping.

In a haematology ward, Candida parapsilosis was found in blood cultures from 4 patients within a month. As C. parapsilosis is known to have a restricted genetic diversity, a combined methodological approach was adopted to establish a possible epidemiological relationship among the isolates (n = 9). Multilocus sequence typing and random amplified polymorphic DNA analysis suggested a clonal origin of the isolates. The clonal origin was confirmed by microsatellite analysis, a method that displayed the highest discriminatory level and readily differentiated cluster isolates from 2 epidemiologically unrelated strains of C. parapsilosis. The use of novel methods of genotyping such as microsatellite analysis will facilitate epidemiological investigations of potential clonal outbreaks of fungaemia.