Nocardia veterana isolated from ascitic fluid of a patient with human immunodeficiency virus infection

Abstract

Nocardia veterana is a recently characterized species within the genus Nocardia, and only three human clinical isolates have been reported for this species. We describe a case of ascitic fluid infection in an immunocompromised patient due to N. veterana. To our knowledge, this is the first report of a Nocardia sp. strain from ascitic fluid and the fourth report of N. veterana isolated from human samples. Chemotaxonomic methods showed the strain to belong to the genus Nocardia, and identification to the species level was done by 16S ribosomal DNA gene sequencing. The antibiotic susceptibility profile of N. veterana is reported here for the second time. The strain was deposited in the Collection of the Pasteur Institute and in the Culture Collection of the University of Göteborg (CIP 107497 and CCUG 46576). The corresponding 16S ribosomal DNA gene sequence is available from the GenBank database under accession number AY149599. A phylogenetic analysis was conducted and showed that N. veterana was most closely related to the recently characterized species Nocardia africana rather than to Nocardia vaccinii, as previously reported.

FIG. 1.

Phylogenetic tree based on 16S rDNA gene sequences indicating the relationships between clinical isolate B430, N. veterana strains, related species N. africana and N. vaccinii, and other type species of the genus Nocardia. The sequence of Rhodococcus equi was used as an outgroup. The scale bar indicates 0.01 substitution per nucleotide position. Accession numbers are given in parentheses.