Profiles of Extrapulmonary Nontuberculous Mycobacteria Infections and Predictors for Species: A Multicenter Retrospective Study

Clinical features and treatment outcomes of bone and joint nontuberculous mycobacterial infections according to immune status: a 9-year retrospective observational cohort

OBJECTIVES

Nontuberculous mycobacteria (NTM) bone and joint infections (BJIs) are uncommon. We evaluated the characteristics of BJIs and identified differences according to immune status.

METHODS

We performed a multicenter retrospective study in France involving patients with documented NTM BJI over a 9-year period. We collected the clinical and microbiological characteristics, management, and clinical outcomes of the patients.

RESULTS

Overall, 95 patients were included, of whom 50.5% (48/95) were immunosuppressed. Tenosynovitis was more frequent in the immunocompetent group, and native arthritis more common in the immunosuppressed group. Mycobacerium marinum and M. abscessus complex were significantly more frequent in the immunocompetent group, and M. avium and M. xenopi were significantly more frequent in the immunosuppressed group. The combination of antibiotherapy with surgery tended to be more frequent in the immunocompetent than the immunosuppressed group (63.8% (30/47) vs 47.8% (22/46), respectively); of the latter, 45.7% (21/46) received antimicrobial therapy alone, a higher frequency than in the immunocompetent group (23.4%, 11/47). The median duration of antimicrobial treatment was similar in the two groups (11 months). Mortality was significantly higher in the immunosuppressed group.

CONCLUSIONS

Although the clinical presentations and the NTM species involved in BJI differed according to immune status, most recovered completely after treatment.

Clinical Characteristics and Outcomes of Extrapulmonary Nontuberculous Mycobacterial Infections in a Tertiary-Care Hospital: A Retrospective Study

Background/Objectives: The incidence of nontuberculous mycobacterial (NTM) infections has increased globally; however, the clinical manifestations and optimal treatment strategies for extrapulmonary NTM infections remain poorly defined. This study assessed the clinical manifestations and treatment outcomes of extrapulmonary NTM infections. Methods: Data from adult patients with suspected extrapulmonary NTM infections at a tertiary-care hospital from 2009-2022 were categorized into NTM disease and isolation groups. Diagnosis of NTM disease relied on stringent criteria, whereas isolation required NTM isolation without meeting the criteria for infection. Results: Among 75 patients evaluated, 32 (42%) were diagnosed with NTM disease and 43 (57%) with NTM isolation. History of immunosuppressant use within the past 3 months (p = 0.070) and injection (p = 0.001) were more frequent in the disease group. The median interval from symptom onset to evaluation was 106.6 and 20 days in the disease and isolation groups, respectively. The prevalence of positive NTM polymerase chain reaction results (36.4%, p = 0.003) and acid-fast bacillus staining (39.1%, p < 0.001) was significantly higher in the disease group than in the isolation group. Mycobacterium intracellulare (21.9%), M. abscessus (15.6%), M. chelonae (9.4%), and M. fortuitum complex (9.4%) were the most frequently identified species. Of the 27 patients in the disease group who received treatment, 13 improved, four experienced treatment failure, seven were lost to follow-up, and three died during treatment, with one death directly attributable to NTM disease. Conclusions: NTM disease exhibits a spectrum of clinical manifestations. Accurate diagnosis is crucial for initiating effective treatment.

Identification and Antimicrobial Susceptibilities for Patients with Non-tuberculous Mycobacteria Infection in Jeju Island: Single-Center Retrospective Study

BACKGROUND

The distribution of species and characteristics of non-tuberculous mycobacteria (NTM) differ, and surveillance data for changes in antimicrobial susceptibilities of NTM is insufficient. This study analyzed the changes in antimicrobial susceptibility trends across NTM species and assessed the appropriateness of empirical antimicrobial drugs for NTM.

MATERIALS AND METHODS

We retrospectively analyzed the clinical characteristics, including demographics, distribution of NTM species, antimicrobial drug susceptibilities, and outcomes, at a teaching hospital in Jeju Island from 2009 - 2022.

RESULTS

Overall, 342 patients were included in the analysis; 93.0% were classified into the pulmonary group (PG) and 7.0% into the extrapulmonary group (EPG). The isolation rate of Mycobacterium avium was significantly higher in PG (36.8% vs. 0%, P = 0.001), while that of Mycobacterium fortuitum was significantly higher in EPG (4.5% vs. 31.3%, P = 0.001). The antimicrobial susceptibility rate is higher against clarithromycin (89.9%) and amikacin (83.3%) and lower against rifampin (54.7%) and ethambutol (28.1%). The susceptibility rate to clarithromycin was over 80%, but those to rifampin and ethambutol showed decreasing annual trends. Of the 162 patients who received empirical antimicrobial therapy, actual antimicrobial susceptibility rates were high (90.1%) using empirical macrolide, and relatively low using ethambutol and rifampin (28.0% and 58.8%, respectively).

CONCLUSION

This is the first study of analysis of the distribution, baseline characteristics, and antimicrobial susceptibility of isolated NTM species in pulmonary and extrapulmonary patients in Jeju Island over 10 years. Policies that continuously monitor changes in susceptibility rate are required to ensure effective treatment strategies.

Epidemiology, clinical characteristics, and outcomes of nontuberculous mycobacterial skin, soft tissue, and bone infections from a single center over a 10-year period

Introduction

Non-tuberculous mycobacteria (NTM) cause a wide variety of clinical syndromes. Data guiding diagnosis and treatment of NTM skin and soft tissue infections (SSTI) and bone infections are limited. We sought to better understand SSTI and bone infections caused by NTM.

Methods

All NTM clinical isolates recovered at Brooke Army Medical Center from 2012 to 2022 were screened; SSTI and bone isolates were included. Electronic health records were reviewed for epidemiologic, microbiologic, and clinical data. Infections were defined as recovery of one or more NTM isolate from skin, soft tissue, or bone cultures with a corresponding clinical syndrome.

Results

Forty isolates of skin, soft tissue, or bone origin from 29 patients were analyzed. Twenty (69 %) patients, majority female (14/20, 70 %), had infecting isolates, most commonly secondary to surgery (35 %) or trauma (35 %). Six of 20 (30 %) had bone infections. Time from symptom onset to isolate recovery was a median 61 days (IQR 43-95). Eight (40 %) had combined medical/surgical therapy, 8 (40 %) had surgery alone, and 4 (20 %) had medical therapy alone. M. abscessus was more frequently isolated from patients with true infections.

Conclusions

Data supporting diagnosis and treatment decisions in NTM SSTI/bone infections is sparse. In this study the majority of NTM isolated were true infections. We confirm that surgery and trauma are the most common routes of exposure. The delay between symptom onset and directed therapy and the wide variety of treatment regimens highlight a need for additional studies delineating criteria for diagnosis and treatment.

Clinical characteristics of extrapulmonary nontuberculous mycobacteria infections in comparison with pulmonary infections: A single-center, retrospective study in Japan

INTRODUCTION

The prevalence of nontuberculous mycobacteria (NTM) infections is increasing worldwide. Although NTM can affect extrapulmonary organs, studies on the clinical characteristics of extrapulmonary NTM are rare.

METHODS

We retrospectively analyzed patients who were newly diagnosed with NTM infections at Hiroshima University Hospital between 2001 and 2021 to investigate species distribution, infected sites, and risk factors of extrapulmonary NTM compared to pulmonary NTM.

RESULTS

Of the 261 NTM infections, 9.6% and 90.4% had extrapulmonary and pulmonary NTM, respectively. The mean ages of patients with extrapulmonary and pulmonary NTM were 53.4 and 69.3 years, 64.0% and 42.8% were male, 36.0% and 9.3% received corticosteroids, 20.0% and 0% had acquired immune deficiency syndrome (AIDS), and 56.0% and 16.1% had any immunosuppressive conditions, respectively. Younger age, corticosteroid use, and AIDS were associated with extrapulmonary NTM. In pulmonary NTM, Mycobacterium avium complex (MAC) accounted for 86.4% of NTM species, followed by M. abscessus complex (4.2%), whereas in extrapulmonary NTM, M. abscessus complex, MAC, M. chelonae, and M. fortuitum accounted for 36.0%, 28.0%, 12.0%, and 8.0%, respectively. Compared to pulmonary NTM, extrapulmonary NTM were significantly more likely to be rapid-growing mycobacteria (RGM) (56.0% vs. 5.5%). The most common sites of infection were the skin and soft tissues (44.0%), followed by the blood (20.0%), tenosynovium, and lymph nodes (12.0%).

CONCLUSION

Younger age and immunosuppressive conditions are associated with extrapulmonary NTM, with a higher prevalence of RGM in extrapulmonary NTM than in pulmonary NTM. These results provide a better understanding of extrapulmonary NTM.

Sweet’s Syndrome Accompanied by Coinfection with Multiple Pathogens and Disseminated Mycobacterium phlei Infection Presenting with Osteolytic Destruction During 12 Years of Follow-Up: A Rare Case Report

Background

Anti-IFN-γ autoantibodies (AIGAs) are closely related to the disseminated infection of multiple pathogens. Mycobacterium phlei (M. phlei) is a nonpathogenic nontuberculous mycobacteria (NTM), and M. phlei infection of the bone is extremely rare. We report a rare case of high-titer AIGAs presenting with Sweet’s syndrome (SS) accompanied by opportunistic coinfection with multiple pathogens during 12 years of follow-up. The patient in this case also developed disseminated M. phlei infection with osteolytic destruction after treatment for SS.

Case Presentation

A 68-year-old Chinese woman was admitted to our hospital in August 2009 due to fever and cough with expectoration for 3 months. The patient was successively infected with Klebsiella pneumoniae, herpes zoster virus and Candida. Chest computed tomography (CT) showed recurrent consolidations in different lung fields. After 15 months of antimicrobial treatment, the patient experienced partial recovery. In September 2010, the patient was pathologically diagnosed with SS due to the presence of multiple rashes. After prednisone and thalidomide treatment, the rashes subsided, and the pulmonary lesions had completely absorbed. In May 2011, the patient was diagnosed with disseminated tuberculosis and was administered anti-tuberculosis therapy for 3 months without improvement. NTM was subsequently cultured from her sputum and chest wall pus, and she improved after 20 months of anti-NTM therapy. In March 2016, the patient developed osteolytic destruction of the C7-T2 vertebral bodies with a back abscess. NTM was eventually cultured from the dorsal abscess pus and further identified as M. phlei. High-titer AIGAs were detected in the patient’s serum. After another round of aggressive anti-NTM therapy, the patient was finally cured.

Conclusion

Patients with AIGA-associated anti-cytokine autoantibody disease can present with multiple opportunistic infections and SS involving the lung. AIGA-associated immunodeficiency leads to infection with nonpathogenic M. phlei, which is refractory, can cause relapse, and even leads to osteolytic destruction.

Retrospective Analysis of 10 Cases of Disseminated Nontuberculous Mycobacterial Disease with Osteolytic Lesions

Purpose

Disseminated nontuberculous mycobacterial (DNTM) infection can involve multiple organs, including the lungs, skin and soft tissues and lymph nodes. However, NTM infection leading to osteolysis has been rarely reported. Here, we analyzed the clinical features, osteolytic mechanisms, treatment and prognosis of patients with DNTM disease with osteolytic lesions.

Patients and Methods

This retrospective study was conducted between January 1, 2011, and December 31, 2020, at the First Affiliated Hospital of Guangxi Medical University and the Fourth People’s Hospital of Nanning City. Patients who had culture and/or histopathological proof of DNTM disease with osteolytic lesions were included.

Results

Ten HIV-negative patients with DNTM disease with osteolytic lesions were enrolled. Five of these patients had underlying diseases. Seven and three of the patients were positive and negative for anti-interferon-γ autoantibodies (AIGAs), respectively. The AIGA positivity rate was 70% (7/10). Ostealgia and anemia were the most common symptoms, followed by fever, emaciation, cough, expectoration, anorexia, subcutaneous abscesses and lymphadenopathy. Leukocyte and neutrophil counts were increased. The most common sites were the vertebrae, sternum, clavicle and ribs, although the femur, ilium, humerus, and scapula were also involved. Radiography and computed tomography (CT) showed moth-eaten or irregular destruction of bone, bone defects, pathological fracture, periosteal proliferation and surrounding abscesses. Emission CT (ECT) bone scans showed significantly increased uptake in many skeletal regions. Positron emission tomography(PET)/CT showed metabolic activity in multiple bones. All patients received anti-nontuberculous therapy, and five underwent surgery. Two died during treatment.

Conclusion

DNTM infection of bone and leading to osteolysis usually occurs in patients with AIGA-positive antibodies. DNTM disease with osteolysis is characterized by increased leukocytes and neutrophil counts, focal suppurative granulomas, and multiple areas with moth-eaten or irregular destruction of bone with increased radioactive concentrations. Early diagnosis and timely, effective combination anti-NTM therapy can improve the prognosis.