Case series of intestinal microsporidiosis in non-HIV patients caused by Encephalitozoon hellem

Abstract

Intestinal microsporidiosis is most often caused by Enterocytozoon bieneusi, and to a lesser extent by species of the genus Encephalitozoon. Until now, Encephalitozoon hellem was not clearly known to induce disease restricted to the intestine, or rarely in HIV subjects or in tropical countries. We report here 11 cases of delineated intestinal microsporidioses due to E. hellem diagnosed in France in non-HIV patients. Briefly, all patients were immunocompromised. They all suffered from diarrhoea, associated in nearly 50% of cases with weight loss. Concerning treatment, 5/11 patients had a discontinuation or a decrease of their immunosuppressive therapy, and 4/11 received albendazole. All patients recovered. Five different genotypes were identified based on the rRNA ITS sequence.

Keywords: Encephalitozoon hellem; diarrhea; internal transcribed spacer; intestinal disease; microsporidiosis.

Figure 1.

Phylogenetic analysis of ITS sequences of Encepahlitozoon hellem isolates from the present study and reference sequences (outgroup: Encephalitozoon cuniculi). The evolutionary history was inferred by using the Maximum Likelihood method based on the Hasegawa-Kishino-Yano model with a discrete Gamma distribution (10,000 replicates). Best model determination and phylogenetic analyses were performed using MEGA 7 software [4].