A Case of Mycobacterium immunogenum Skin Infection Associated with Myelodysplastic Syndrome and Autoimmune Hemolytic Anemia

Abstract

An 83-year-old woman suffering from myelodysplastic syndrome and autoimmune hemolytic anemia who had been treated with oral prednisolone presented with redness, swelling, nodules, and subcutaneous indurations on the left lower leg. Mycobacteria were cultured from both a biopsy specimen and a discharge from a skin lesion and identified as Mycobacterium (M.) immunogenum by DNA sequence analysis of the 16S rRNA gene. The results of a DNA-DNA hybridization test suggested that the bacteria were M. abscessus. M. immunogenum was characterized as a new species very close to M. chelonae and M. abscessus in 2001. To our knowledge, infections due to M. immunogenum, including skin infection, have not previously been reported in Japan. However, it is possible that they have been erroneously reported as either M. chelonae or M. abscessus infections.