Polymerase chain reaction reverse cross-blot hybridization assay in the diagnosis of sporotrichoid Mycobacterium marinum infection

In this paper, we report a patient in whom Mycobacterium marinum sporotrichoid infection was diagnosed using polymerase chain reaction (PCR) amplification of the 16S rRNA gene and subsequent: analysis of the amplified product in a reverse cross-blot hybridization assay with mycobacterial species-specific probes. This molecular method allowed us rapidly to detect and identify this organism directly in the patient's lesional sit-in biopsy rather than in cultures in conventional media. The identification provided by PCR-reverse cross-blot hybridization assay was confirmed by examination of the morphological and biochemical features and by high-performance liquid chromatography analysis of mycolic acid from the clinical isolate, suggesting the validity of our molecular approach.