Evaluation of a simple method for growing Mycobacterium haemophilum.

Surface paper strips containing hemin (X factor) were tested on Middlebrook 7H10 agar and Lowenstein-Jensen medium to determine if the growth requirement of Mycobacterium haemophilum for iron-containing complexes could be met by this simplified method. One reference strain and seven strains of this species isolated from patients showed good growth around the strips on 7H10 within 2 weeks but failed to grow on Lowenstein-Jensen medium with X-factor strips. Middlebrook 7H10 medium with X-factor strips may be a useful alternative to the preparation of specialized media for the recovery of M. haemophilum from clinical specimens.