A Cluster of Nontuberculous Mycobacterial Tenosynovitis Following Hurricane Relief Efforts

A neonate with multiple hand flexor tendon ruptures due to methicillin-susceptible Staphylococcus aureus sepsis: a case report

BACKGROUND

Neonatal pyogenic tenosynovitis is a highly emergent soft tissue infection. We report a case of a neonate with pyogenic tendinopathy and tendon rupture diagnosed by ultrasonography (US). He subsequently developed pyogenic arthritis and osteomyelitis during antimicrobial therapy.

CASE PRESENTATION

A 7-day-old boy was admitted to our hospital with redness and swelling of the right index finger. US on admission showed rupture of the flexor tendon of the right index finger with inactivity. The day after admission, he developed pyogenic arthritis of the right elbow and, subsequently, pyogenic osteomyelitis. Staphylococcus aureus was identified through bacterial culture, and the patient was treated with intravenous antibiotics for 6 weeks. However, after discharge from our hospital, rupture of the flexor tendon of the left thumb was confirmed. A two-stage flexor tendinoplasty was completed at the age of 2 years and 1 month for the flexor tendon rupture on his right index finger.

CONCLUSIONS

In addition to blood culture, ultrasonographic evaluation should be performed in neonates with erythematous and swollen joints to identify the focus of infection as soon as possible. Moreover, repeated regular US examination is important in the follow-up of bone and soft tissue infections.

Vertebral Osteomyelitis Caused by Mycobacterium arupense Mimicking Tuberculous Spondylitis: First Reported Case and Literature Review

Mycobacterium arupense is a slow-growing, nontuberculous mycobacterium widely found in the environment and is known to cause tenosynovitis and osteomyelitis, mainly in the hands and wrists. We present the first case of vertebral osteomyelitis caused by M arupense in a 78-year-old man with renal cell carcinoma. The patient had a history of tuberculous pleuritis in childhood. Although the nucleic acid amplification test of the vertebral tissue for Mycobacterium tuberculosis was negative, we initiated tuberculosis treatment based on the history and pathological findings of auramine-rhodamine-positive organisms and epithelioid cell granulomas. Subsequently, the isolated mycobacterium was identified as M arupense by genome sequencing. Accordingly, the treatment regimen was changed to a combination of clarithromycin, ethambutol, and rifabutin. Owing to a subsequent adverse event, rifabutin was switched to faropenem, and the patient was treated for a total of 1 year. In previous literature, we found 15 reported cases of bone and soft tissue infections caused by M arupense, but none of them had vertebral lesions. Physicians should be aware that M arupense can cause vertebral osteomyelitis mimicking tuberculous spondylitis. In addition, molecular testing of isolated mycobacteria is essential for diagnosis, even if tuberculous spondylitis is suspected.

Nontuberculous Mycobacteria: Ecology and Impact on Animal and Human Health

Nontuberculous mycobacteria (NTM) represent an important group of environmentally saprophytic and potentially pathogenic bacteria that can cause serious mycobacterioses in humans and animals. The sources of infections often remain undetected except for soil- or water-borne, water-washed, water-based, or water-related infections caused by groups of the Mycobacterium (M.) avium complex; M. fortuitum; and other NTM species, including M. marinum infection, known as fish tank granuloma, and M. ulcerans infection, which is described as a Buruli ulcer. NTM could be considered as water-borne, air-borne, and soil-borne pathogens (sapronoses). A lot of clinically relevant NTM species could be considered due to the enormity of published data on permanent, periodic, transient, and incidental sapronoses. Interest is currently increasing in mycobacterioses diagnosed in humans and husbandry animals (esp. pigs) caused by NTM species present in peat bogs, potting soil, garden peat, bat and bird guano, and other matrices used as garden fertilizers. NTM are present in dust particles and in water aerosols, which represent certain factors during aerogenous infection in immunosuppressed host organisms during hospitalization, speleotherapy, and leisure activities. For this Special Issue, a collection of articles providing a current view of the research on NTM-including the clinical relevance, therapy, prevention of mycobacterioses, epidemiology, and ecology-are addressed.

Disseminated Mycolicibacter arupensis and Mycobacterium avium co-infection in a patient with anti-interferon-γ neutralizing autoantibody-associated immunodeficiency syndrome

BACKGROUND

Disseminated infections of Mycolicibacter arupensis, a slowly growing nontuberculous mycobacteria (NTM) which causes synovitis, osteomyelitis, or pulmonary infections have rarely been reported. We report a case of disseminated M. arupensis and Mycobacterium avium co-infection in a patient with anti-interferon (IFN)-γ neutralizing autoantibody-associated immunodeficiency syndrome.

CASE PRESENTATION

A 68-year-old Japanese male without human immunodeficiency virus infection was referred with complaints of persistent low-grade fever, arthralgia of the upper limbs, and weight loss of 10 kg. Cervical and mediastinal lymphadenopathies as well as a nodular opacity in the right lung were detected, and biopsy specimens of the cervical lymph node yielded M. arupensis without evidence of malignant cells. M. arupensis was also detected in sputum and peripheral blood. Computed tomography (CT) revealed deterioration of the right supraclavicular lymphadenopathy with internal necrosis and multiple low-density splenic lesions. Bone marrow and aspirates from the cervical lymph node collected at initiation of treatment yielded M. avium. The presence of anti-IFN-γ neutralizing autoantibodies was detected, leading to a diagnosis of co-infection of M. arupensis and M. avium with anti-IFN-γ neutralizing autoantibody-associated immunodeficiency syndrome. Post initiation of treatment with clarithromycin, ethambutol, and rifabutin, his fever declined, and his polyarthritis resolved. He developed disseminated varicella zoster during treatment; however, a follow-up CT scan six months after treatment revealed improvement of the lymphadenopathies, consolidation in the right lung, and splenic lesions.

CONCLUSION

This is the first report of disseminated M. arupensis and M. avium co-infection in a patient with anti-IFN-γ neutralizing autoantibody-associated immunodeficiency syndrome.