Diagnosing disseminated Mycobacterium haemophilum: the importance of 16S rRNA PCR

Dermatology practice updates in mycobacterial disease

Atypical mycobacterial infections are commonly acquired through exposure to water, and tuberculosis remains highly endemic in many parts of the world. In this era of global connection, travel, and immigration, it is more important than ever to maintain a high index of suspicion for infection from cutaneous tuberculosis and atypical mycobacteria. Epidemics related to surgical procedures have been related to inadequate sterilization, as almost 50% of public water supplies harbor mycobacteria. Improved diagnostic techniques for these microbes, including Auramine-Rhodamine staining and rapid detection of mycobacteria and drug susceptibilities through PCR and MALDI-TOF, have improved detection and treatment outcomes. Given an increasing number of patients on immunosuppressive therapies, clinicians must remain vigilant.

Mycobacterium haemophilum infection in immunocompetent adults: a literature review and case report

BACKGROUND

Mycobacterium haemophilum has been increasingly found in severely immunocompromised patients but is scarcely reported in immunocompetent adults.

METHODS

We systematically reviewed previous literature to identify studies on infection in immunocompetent adults. Articles reporting at least one case of M. haemophilum infection were included. We excluded articles involving patients who had immunosuppression-related diseases and routinely used glucocorticoids or immunosuppressants. We also reported a case of a young immunocompetent woman infected by M. haemophilum along the eyebrows, which was probably due to the use of an eyebrow pencil retrieved from a sink drain.

RESULTS

Twelve qualifying articles reporting M. haemophilum infection in immunocompetent adults were identified. Among them, most cases report skin lesions along the eyebrows, and the remaining had cervicofacial lymphadenitis, lesions on the arm or fingers, inflammation in the eyeballs, or ulceration in the perineal region. Most cases were caused by tattoos, make-up, injury, or surgical operation. For diagnosis, specialized tissue culture sensitivity was roughly 75%, and polymerase chain reaction (PCR) test sensitivity was approximately 89%. Triple antibiotic therapy for 3 to 24 months, or surgical excision was effective in controlling infection.

CONCLUSION

M. haemophilum infection should be considered if routine antibacterial and glucocorticoid treatments are ineffective against the disease, even in healthy adults. To definitively diagnose this infection, conditioned tissue culture or PCR testing is required. Treatment usually involves a combination of multiple antibiotics and, if necessary, surgical removal of infected tissue.

Mycobacterium haemophilum infection with cutaneous involvement: two case reports and an updated literature review: Mycobacterium haemophilum skin infection

Mycobacterium haemophilum (MH) is a slow-growing, non-tuberculous Mycobacterium that most commonly causes infections in immunocompromised patients. The skin is the most prevalent site of infection and can be an isolated presentation or part of a disseminated disease. Herein, we reported a case of isolated MH infection of the hand and a case of disseminated MH infection with multiple skin lesions. In addition, other MH cases with cutaneous involvement over the last 10 years, from 2011-2022, were reviewed and analyzed. Among the 79 included cases, the common skin findings in MH infections included nodules, ulcers, abscesses, swelling, and pustules. Middle-aged patients with iatrogenic immunosuppression from glucocorticoids, mycophenolate mofetil, cyclosporine, and cyclophosphamide are the most susceptible to MH infection, with a higher risk of dissemination to internal organs. Disseminated MH infections commonly present as tenosynovitis, arthritis/arthralgia, or osteomyelitis. There is a lack of strong evidence for treatment; however, triple therapy of quinolone, macrolides, and rifampicin is most often used in clinical practice. The overall prognosis is good. The presence of iatrogenic immunocompromised diseases, lesions involving the proximal limbs, and dissemination of MH infections are associated with worse clinical outcomes.

Hautbeteiligung bei Infektionen mit Mycobacterium haemophilum: Zwei Fallberichte und eine aktualisierte Literaturübersicht: Mycobacterium haemophilum infection with cutaneous involvement: Two case reports and an updated literature review

Mycobacterium haemophilum (MH) ist ein langsam wachsendes, nicht‐tuberkulöses Mykobakterium. Infektionen treten am häufigsten bei Patienten mit beeinträchtigtem Immunsystem auf; sie manifestieren sich meist an der Haut und kommen isoliert oder bei disseminierten Infektionen vor. Wir berichten hier über einen Fall mit isolierter MH‐Infektion an der Hand sowie über einen weiteren Fall von disseminierter MH‐Infektion mit multiplen Hautläsionen. Zusätzlich haben wir weitere Fallberichte über MH‐Infektionen mit kutaner Beteiligung aus den letzten zehn Jahren (2011–2022) ausgewertet. Die am häufigsten beobachteten Hautmanifestationen der insgesamt 79 Fälle waren Knötchen, Ulzera, Abszesse, Schwellungen und Pusteln. Patienten mittleren Alters mit iatrogener Immunsuppression durch Glucocorticoide, Mycophenolat‐Mofetil, Ciclosporin und Cyclophosphamid scheinen besonders anfällig für MH‐Infektionen zu sein und haben auch ein höheres Risiko für eine Dissemination in die inneren Organe. Disseminierte MH‐Infektionen manifestieren sich gewöhnlich als Tenosynovitis, Arthritis/Arthralgie oder Osteomyelitis. Derzeit gibt es keine starke Evidenz für bestimmte Therapeutika; in der Praxis wird am häufigsten eine Dreifachkombination aus Chinolon, Makroliden und Rifampicin eingesetzt. Die Prognose ist allgemein gut. Iatrogene Immunsuppression, Läsionen im proximalen Bereich der Extremitäten sowie disseminierte Manifestation sind mit schlechteren klinischen Verläufen assoziiert.