Cutaneous Mycobacterium haemophilum infections in immunocompromised patients in a dermatology clinic in Singapore

Introduction: Mycobacterium haemophilum, a nontuberculous mycobacterium (NTM) that was first described in 1978, is a pathogen that can cause an array of symptoms in immunocompromised patients, predominantly cutaneous. Clinical Picture: We report our hospital's experience with the first 3 patients diagnosed with this infection from 1994 to 2002. All were women; one had systemic lupus erythematosus (SLE), one had mycosis fungoides and the last had Sjogren's syndrome with recurrent bacterial infections, although the specific nature of her immunocompromised state has not been defined. All were HIV negative. All 3 women presented with cutaneous lesions - the first with recurrent erythematous plaques on the limbs and back, the second with tender nodules and abscesses on the knees, and the third with papular eruptions on the cheek. Treatment/Outcome: All responded to a combination of antibiotics and are presently still undergoing treatment and follow-up. Conclusion: Infections caused by M. haemophilum occur mainly in immunocompromised patients. They can present with a variety of cutaneous manifestations, which require a high index of suspicion and coordination between the treating physician and the laboratory for diagnosis. Combination antibiotic treatment is recommended, and patients should be followed up after treatment to survey for possible relapse.