Varied Presentations and Responses to Treatment of Infections Caused by Mycobacterium haemophilum in Patients with AIDS

Abstract

We describe three patients with AIDS who developed clinically significant infection with Mycobacterium haemophilum. One patient had skin and bone involvement and suspected laryngeal involvement; the second had extensive abdominal adenopathy with partial bowel obstruction; and the third presented with limited skin involvement. Each patient responded transiently to antimycobacterial therapy, but disease recurred and progressed in all three cases. Recovery of M. haemophilum requires a high level of clinical suspicion and special handling of mycobacterial cultures by the microbiology laboratory, including cultivation on enriched chocolate agar or heme-supplemented media and incubation at 30 degrees C for up to 8 weeks. Characteristic patterns of drug susceptibility for this organism have been only partially defined. Reported responses to antimycobacterial therapy in AIDS patients with M. haemophilum infection have been poor, and the optimal therapeutic regimen is not yet known. The prognosis for recovery appears to depend heavily on host-related factors, particularly the degree of immunosuppression.

Mycobacterium haemophilum as a Novel Etiology of Cervical Lymphadenitis in an Otherwise Healthy Adult Patient

“…Interestingly, four of the seven cases (57%) had histories of either recent buccal trauma (the patient described here) or tooth extraction (three patients) prior to the onset of lymphadenitis; histories of buccal trauma or tooth extraction were not noted in the charts for the remaining three cases. Mycobacterium haemophilum, a slow-growing nontuberculous mycobacterium, is more commonly associated with infections involving the lymph nodes, skin and soft tissues, bone and joints, and lungs in patients with profound immunocompromise, including those with hematological malignancies, those with AIDS, transplant recipients, and those receiving immunosuppressive medications for autoimmune conditions (1,2,5,7,9,10,12,14,15,18). In immunocompetent patients the organism has been described as a cause of a pulmonary nodule in an adult and of localized lymphadenitis, typically cervicofacial, in healthy pediatric patients, the latter being hypothesized to be due to lymphatic drainage from the oropharynx (3,11,16,17).…”

Disseminated Mycobacterium genavense Infection in Two Patients with AIDS

“…In our laboratory all BACTEC specimens that yield mycobacteria are routinely treated in the above-described manner if they contain blood or bone marrow before the luminescent probe procedure is performed. Although the mycobacteria initially cultured in BACTEC bottles were successfully subcultured in other bottles, no growth was obtained on any solid media despite the use of triplicate sets (incubated at 30°C, 35°C, and 42°C) of Middlebrook 7H 10 agar, Lowenstein-Jensen agar, and blood agar as well as enriched chocolate agar for the isolation of Mycobacterium haemophilum [6]. Analysis of 16S ribosomal RNA was carried out by PCR amplification and sequencing with use of the primers and conditions previously described [2].…”

Direct Identification of Mycobacterium haemophilum in Skin Lesions of Immunocompromised Patients by PCR-Restriction Endonuclease Analysis

“…PRA correctly identified M. haemophilum in four smear-positive specimens. Direct identification by PRA takes 2 to 3 working days compared to the 3 to 5 weeks required for culture isolation and identification by conventional methods.In recent years, Mycobacterium haemophilum has emerged as an important human pathogen (6, 10, 12), causing mainly opportunistic infections in severely immunocompromised patients with AIDS and those receiving immunosuppressive therapy after transplantation (1,4,7,8,12,16). M. haemophilum has also been isolated from localized lesions in immunocompetent pediatric patients with cervical lymphadenopathy (3, 9).…”

“…In recent years, Mycobacterium haemophilum has emerged as an important human pathogen (6,10,12), causing mainly opportunistic infections in severely immunocompromised patients with AIDS and those receiving immunosuppressive therapy after transplantation (1,4,7,8,12,16). M. haemophilum has also been isolated from localized lesions in immunocompetent pediatric patients with cervical lymphadenopathy (3,9).…”