Disseminated Mycobacterium massiliense infection in a patient with myelodysplastic syndrome undergoing allogeneic bone marrow transplantation

Patient with Adult T-cell Leukemia and Lung Infection Caused by Mycobacterium abscessus: Successful Treatment with Intensive Chemotherapy Followed by Haploidentical Hematopoietic Stem Cell Transplantation

A 63-year-old woman with adult T-cell leukemia (ATL) lymphomatous type developed a mild dry cough. Computed tomography revealed lung lesions with a tree-in-bud appearance during intensive chemotherapy. Antibodies against Mycobacterium avium complex were positive. Bronchoalveolar lavage culture showed growth of M. abscessus complex. Finally, M. abscessus subsp. massiliense was also identified. Sequential use of antimicrobials, including macrolides, was introduced during intensive chemotherapy, and the patient successfully underwent allogeneic hematopoietic stem cell transplantation (AHSCT). This is the first case report of a patient with ATL complicated by M. massiliense lung infection, who was successfully treated with haploidentical AHSCT using various combinations of antimicrobials.

Prevalence and Characteristics of Non-tuberculous Mycobacteria (NTM) Infection in Recipients of Allogeneic Hematopoietic Stem Cell Transplantation: a Systematic Review and Meta-analysis

PURPOSE

Non-tuberculous mycobacteria (NTM) infections in hematopoietic stem cell transplantation (HSCT) recipients represent a diagnostic and therapeutic challenge. Here, we aimed to review and analyze current literature on incidence, clinical presentation, and outcome of NTM infection after allogeneic HSCT.

METHODS

We performed a systematic review and meta-analysis of available literature regarding NTM infection in children and adults receiving allogeneic HSCT.

RESULTS

We identified 56 articles eligible for the analysis. Among 15 studies, describing 15,798 allogeneic HSCT, we estimated a prevalence of 1.26% (95% CI 0.72, 1.93) of NTM after transplant. Analysis of 175 patients with NTM infection showed a median time of diagnosis of 318 days after HSCT, an increased prevalence in adults (82.9%), and a most frequent pulmonary involvement (44%). Comparison between children and adults revealed an earlier post-transplant disease onset (median 130 days vs 287 days) and most frequent non-pulmonary presentation in children. A vast heterogeneity of therapeutic approach reflected the lack of universal recommendations regarding drug combination and duration of therapy. Overall, NTM-related mortality accounted for 33% in this systematic review.

CONCLUSION

Although rare, NTM infections can complicate post-transplant course with a high mortality rate in children and adults. The lack of prospective studies and guidelines prevents identification of risk factors and therapeutic recommendations.

Nontuberculous mycobacterial infections in patients with hematologic malignancies and recipients of hematopoietic stem cell transplantation

BACKGROUND

The incidence of mycobacterial infections in patients with hematologic malignancies and hematopoietic stem cell transplant (HSCT) recipients is increasing, contributing to significant mortality and morbidity. This review explores the epidemiology, risk factors, clinical presentation, diagnosis, and treatment of nontuberculous mycobacteria (NTM) in this population.

METHODS

A literature search was performed using PubMed with keywords and MeSH terms pertaining to the topics of nontuberculous mycobacteria, hematologic malignancies, hematopoietic stem cell transplant, cellular therapies, chimeric antigen therapies, epidemiology, diagnosis, and treatment. Additionally, we examined the reference lists of the included articles to identify other pertinent studies.

RESULTS

Diagnosing mycobacterial disease among patients with hematologic disease and treatment-associated immunosuppressive conditions is challenging due to the lack of distinctive clinical, radiographic, and laboratory markers, as well as the atypical manifestations compared to immunocompetent patients. Treatment involves using a combination of antibiotics for extended durations, coupled with strategies to achieve source control and reduce immunosuppression when feasible. This is complicated by the absence of clear data correlating in-vitro drug susceptibility and clinical outcome for many antimicrobials use to treat NTM, adverse drug-drug interactions, and the frequent challenges related to poor medication tolerability and toxicities.

CONCLUSION

The rising incidence and corresponding clinical challenges of mycobacterial infections in this unique patient population necessitate a heightened awareness and familiarity of NTM disease by clinicians to achieve timely diagnosis and favorable treatment outcomes.

A Disseminated Mycobacterium Abscessus Infection in a Patient Affected by Pulmonary Graft versus Host Disease: Case Report with a Revision of Literature

Mycobacterium abscessus complex, hereinafter Mab, is a taxonomic group of rapidly growing, nontuberculous mycobacteria (NTM). Despite major advances in understanding virulence, pathogenicity and mechanism of antibiotic resistance, Mab remains a significant cause of pulmonary and extra-pulmonary disease. Herein, we describe a disseminated, macrolide-resistant, Mab subspecies abscessus infection occurring in a severely immune-compromised 34-year-old allotransplanted female patient affected by pulmonary chronic graft versus host disease (cGVHD). The infection was characterized by hematogenous spread, and besides lungs, it involved skin, and soft tissues, resulting in a highly debilitating, painful, and finally fatal disease. Our case describes the severe impact of Mab infections in the setting of allogeneic hematopoietic stem cells transplant (alloHSCT) and related complications. It also highlights the unmet need of preventive and surveillance measures together with the urgency of developing effective vaccines and drugs against emerging NTM. The scarce literature regarding Mab infections in alloHSCT patients is also reviewed.