Mycobacterium chelonae/abscessus complex infection in a liver transplant patient

Mycobacterium abscessus infection in a patient with ornithine transcarbamylase deficiency and liver transplant

Rapidly growing mycobacteria, including Mycobacterium abscessus, have become a common cause of post-procedural infections and are notoriously difficult to diagnose and treat. Here, we report a 10-month-old male status post-orthotopic liver transplantation due to ornithine transcarbamylase deficiency who presented with a 4-month history of hypertrophic and friable granulation tissue of surgical wounds refractory to treatment with broad spectrum antibiotics and surgical debridement. Skin biopsy and tissue culture yielded a diagnosis of M abscessus infection that demonstrated excellent clinical response to appropriate antibiotic and surgical treatment.

Non-tuberculous mycobacterial infections in solid organ transplant recipients: An update

Non-tuberculous mycobacteria are ubiquitous environmental organisms that are now increasingly recognized as important causes of clinical disease in solid organ transplant recipients. Risk factors of non-tuberculous mycobacteria infection are severe immunologic defects and structural abnormalities. Lung transplant recipients are at higher risk for non-tuberculous mycobacterial disease compared to recipients of other solid organs. The clinical presentation could be skin and soft tissue infection, osteoarticular disease, pleuropulmonary infection, bloodstream (including catheter-associated) infection, lymphadenitis, and disseminated or multi-organ disease. Management of non-tuberculous mycobacteria infection is complex due to the prolonged treatment course with multi-drug regimens that are anticipated to interact with immunosuppressive medications. This review article provides an update on infections due to non-tuberculous mycobacteria after solid organ transplantation, and discusses the epidemiology, risk factors, clinical presentation, and management.

Successful management of primary nontuberculous mycobacterial infection of hepatic allograft following orthotopic liver transplantation for hepatitis C

Nontuberculous mycobacteria are a rare cause of disease in solid organ and hematopoietic stem cell transplant recipients. The impact of mycobacterial infections in transplant recipients necessitates prompt diagnosis and early initiation of therapy. However, diagnosis remains difficult and there is a lack of specific recommendations for the choice of anti-mycobacterial drugs, duration of therapy, and monitoring of graft function as well as immunosuppression in these patients. Issues involved in the management are illustrated by an index case of hepatic allograft infection due to Mycobacterium avium complex.

Mycobacterium abscessus: a new player in the mycobacterial field

Mycobacterium abscessus, a relative of Koch's bacillus (the bacterium that causes tuberculosis), has recently emerged as the cause of an increasing number of both community- and hospital-acquired infections in humans; it also constitutes a serious threat for cystic fibrosis patients. This situation is worsened by its exceptionally high natural and acquired antibiotic resistance that complicates treatment. Although a rapid grower, it shares some traits with Koch's bacillus, including the ability to induce a persistent lung disease associated with caseous lesions, a landmark of Mycobacterium tuberculosis infection. Its genome sequence and microarrays are now available, and efficient genetic tools have recently been developed. Here we consider the various advantages of using this species as an experimental model to study tuberculosis and other related mycobacterial diseases.

Successful recovery after disseminated infection due to mycobacterium abscessus in a lung transplant patient: subcutaneous nodule as first manifestation--a case report

Mycobacterium abscessus infection following lung transplantation (LT) has been described in a few cases. It is characterized by a variable initial location and subsequent course in this special risk group of patients, particularly those with cystic fibrosis (CF). Herein we have presented the case of a patient subjected to LT due to CF, who 1 year after transplantation developed a subcutaneous nodule produced by M abscessus, with subsequent hematogenous spread as well as bronchial and bone marrow involvement. Antecedents prior to LT included Staphylococcus aureus colonization and sputum positivity for Aspergillus fumigatus and Scedosporium apioespermum. Treatment with ciprofloxacin and linezolid was started on the basis of the antibiogram findings. The latter antibiotic was replaced by clarithromycin for 6 months. Two years later, the patient remains asymptomatic with respiratory function parameters in the normal range. The infected patient described herein was our only case with sepsis and multisystemic spread. The important mortality among such cases reported in the literature makes early diagnosis and treatment essential.

Nontuberculous mycobacterial infection in hematopoietic stem cell and solid organ transplant recipients

Nontuberculous mycobacteria (NTM) are ubiquitous environmental organisms. In immunocompetent hosts, they are a rare cause of disease. In immunocompromised hosts, disease due to NTM is well documented. Reports of NTM disease have increased in hematopoietic stem cell transplant (HSCT) and solid organ transplant (SOT) recipients. This increase may reflect increased numbers of transplants, intensification of immune suppressive regimens, prolonged survival of transplant recipients, and/or improved diagnostic techniques. The difficulty of diagnosis and the impact associated with infections due to NTM in HSCT and SOT recipients necessitates that, to ensure prompt diagnosis and early initiation of therapy, a high level of suspicion for NTM disease be maintained. The most common manifestations of NTM infection in SOT recipients include cutaneous and pleuropulmonary disease, and, in HSCT recipients, catheter-related infection. Skin and pulmonary lesions should be biopsied for histologic examination, special staining, and microbiologic cultures, including cultures for bacteria, Nocardia species, fungi, and mycobacteria. Mycobacterial infections associated with catheters may be documented by tunnel or blood (isolator) cultures. Susceptibility testing of mycobacterial isolates is an essential component of optimal care. The frequent isolation of NTM other than Mycobacterium avium complex (MAC) from transplant recipients limits the extrapolation of therapeutic data from human immunodeficiency virus-infected individuals to the population of transplant recipients. Issues involved in the management of NTM disease in transplant recipients are characterized by a case of disseminated infection due to Mycobacterium avium complex in a lung transplant recipient, with a review of the relevant literature.