Background/Purpose:

Nontuberculous mycobacteria (NTM) have become pathogens frequently associated with skin infection in patients on immunosuppression. NTM is not unusual in lupus patients and the unawareness of this complication delays diagnosis and treatment. Studies on infections in lupus identified the common typical bacterial pathogens and little has been published on atypical pathogens in particular NTM.

We aimed to systematically review the medical literature addressing skin NTM in lupus.

Methods:

We searched Ovid Medline (1946 to March 12, 2012), Embase (1980 to March 12, 2012) for relevant publications. A study was included in the review if: 1) it included lupus patients with NTM of mucocutaneous system or soft tissue 2) it was published up to March 12, 2012 and 3) it had well-documented clinical summaries and relevant information to the objective of this study. We scanned the titles and abstracts for initial selection. Selected articles were retrieved in full and two reviewers assessed them for eligibility and extracted the data. Descriptive statistics were used to report the results of the analysis.

Results:

Of the 1356 retrieved abstracts, 17 publications were identified and 25 cases of skin NTM were extracted. In this review we included only patients with skin NTM and in all but 5 patients the infection was limited to the skin. The majority of the cases occurred in females (92%). The mean age at the time of the infection was 41 ± 13.3 years, with mean lupus duration of 12.9± 6.7 years. Skin presentations in this review were painless to mildly painful and ranged from papules, plaques, nodules to ulcerative lesions and abscesses and few patients developed constitutional symptoms in particular fever.

NTM in lupus patients occurred after relatively long period from the initial diagnosis of lupus and after the patients had been exposed to steroids and immunosuppressants. NTM occurred in the setting of active as well as inactive lupus. The pathogen species identified in this review included mainly M. Chelonae (9 patient-events [PE]), M. Haemophilum (4 PE), M. Avium (3 PE), M. Kansasii (2 PE), M. Fortuitum (2 PE), M. Scrofulaceum (1 PE), M. Marinatum (1 PE), M. Szulgai (1 PE) and M.abscessus (1 PE). In 4 PE the culture was either negative or the specific species was not identified.

Surgical intervention in particular debridement of skin lesions were considered if needed. Empirical monotherapy therapy can be initially initiated and the final choice of antibiotics should rely on the susceptibility of the culture and clinical response. The majority of the patients’ lesions improved/recovered with treatment. Nevertheless, two patients developed disseminated M. Chelonae and Fortuitum respectively and this resulted in death.

The most commonly used antibiotics in this review were ciprofloxacin, clarithromycin, ethambutol, isoniazide, rifampicin, doxycyline, amikacin, ethambutol and minocycline.

Conclusion:

A high index of suspicion in lupus patients is required to diagnose NTM, as the initial presentation of NTM can mimic lupus skin manifestations. NTM should be suspected in any patient with indolent deep-nodular skin lesions, especially if routine bacterial cultures are negative.