Nontuberculous mycobacterial infections in solid organ transplantation

Asian Pacific Association for the Study of the Liver clinical practice guidelines on liver transplantation

Liver transplantation is a highly complex and challenging field of clinical practice. Although it was originally developed in western countries, it has been further advanced in Asian countries through the use of living donor liver transplantation. This method of transplantation is the only available option in many countries in the Asia-Pacific region due to the lack of deceased organ donation. As a result of this clinical situation, there is a growing need for guidelines that are specific to the Asia-Pacific region. These guidelines provide comprehensive recommendations for evidence-based management throughout the entire process of liver transplantation, covering both deceased and living donor liver transplantation. In addition, the development of these guidelines has been a collaborative effort between medical professionals from various countries in the region. This has allowed for the inclusion of diverse perspectives and experiences, leading to a more comprehensive and effective set of guidelines.

Opportunistic Infections Post-Lung Transplantation: Viral, Fungal, and Mycobacterial

Opportunistic infections are a leading cause of lung transplant recipient morbidity and mortality. Risk factors for infection include continuous exposure of the lung allograft to the external environment, high levels of immunosuppression, impaired mucociliary clearance and decreased cough reflex, and impact of the native lung microbiome in single lung transplant recipients. Infection risk is mitigated through careful pretransplant screening of recipients and donors, implementation of antimicrobial prophylaxis strategies, and routine surveillance posttransplant. This review describes common viral, fungal, and mycobacterial infectious after lung transplant and provides recommendations on prevention and treatment.

Nontuberculous Mycobacterial Infections in Pediatric Solid Organ Transplant and Hematopoietic Cell Transplant Recipients

The diagnosis of nontuberculous mycobacterial infections is challenging in pediatric solid organ transplant and hematopoietic cell transplant recipients due to the absence of specific clinical manifestations, limitations of sampling, prolonged times for culture and identification, and difficulty discerning colonization from clinical disease. Treatment is dependent on the nontuberculous mycobacterial species, disease type, and pattern of drug resistance. Treatment of nontuberculous mycobacterial infections involves prolonged durations of therapy using multiple medications, which are limited by toxicities and drug-drug interactions.

Opportunistic Infections Post-Lung Transplantation: Viral, Fungal, and Mycobacterial

Opportunistic infections are a leading cause of lung transplant recipient morbidity and mortality. Risk factors for infection include continuous exposure of the lung allograft to the external environment, high levels of immunosuppression, impaired mucociliary clearance and decreased cough reflex, and impact of the native lung microbiome in single lung transplant recipients. Infection risk is mitigated through careful pretransplant screening of recipients and donors, implementation of antimicrobial prophylaxis strategies, and routine surveillance posttransplant. This review describes common viral, fungal, and mycobacterial infectious after lung transplant and provides recommendations on prevention and treatment.

Disseminated Nontuberculous Mycobacterium Presenting as Chronic Diarrhea and Wasting

Infections due to nontuberculous mycobacterium (NTM) are important in chronically immunosuppressed populations and are a particular threat to solid organ transplant recipients (SOT). However, they are not a common occurrence and have protean manifestations, making it important that clinicians maintain a high degree of suspicion in the correct patient population. Mycobacterium avium complex (MAC) usually presents with pulmonary involvement in immunocompetent population and disseminated disease in SOT patients with fever of unknown origin, lymphadenopathy, and cutaneous lesions being part of the well-known presentation. It is not commonly described as causing severe diarrhea. Here, we present an interesting case of a patient with a kidney and pancreas transplant who presented with debilitating wasting and chronic diarrhea. Biopsies and cultures confirmed MAC. To our knowledge, this is the first case report of MAC causing severe wasting diarrhea in renal transplant patients. The patient was treated with a multidrug regimen. Given the rare presentation of MAC presenting as chronic diarrhea, the treatment regimen is not standardized and infectious disease specialists should be involved early on. Up to 30% of renal transplant patients infected with NTM lose graft function and 20% die. Unfortunately, our patient suffered both these outcomes.

Whole Genome Sequencing in the Management of Non-Tuberculous Mycobacterial Infections

Infections caused by non-tuberculous mycobacteria (NTM) have been a public health problem in recent decades and contribute significantly to the clinical and economic burden globally. The diagnosis of infections is difficult and time-consuming and, in addition, the conventional diagnostics tests do not have sufficient discrimination power in species identification due to cross-reactions and not fully specific probes. However, technological advances have been made and the whole genome sequencing (WGS) method has been shown to be an essential part of routine diagnostics in clinical mycobacteriology laboratories. The use of this technology has contributed to the characterization of new species of mycobacteria, as well as the identification of gene mutations encoding resistance and virulence factors. Sequencing data also allowed to track global outbreaks of nosocomial NTM infections caused by M. abscessus complex and M. chimaera. To highlight the utility of WGS, we summarize recent scientific studies on WGS as a tool suitable for the management of NTM-induced infections in clinical practice.

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.

Mycobacteria: Selection of Transplant Candidates and Post-lung Transplant Outcomes

Mycobacterium is a large, clinically relevant bacterial genus made up of the agents of tuberculosis and leprosy and hundreds of species of saprophytic nontuberculous mycobacteria (NTM). Pathogenicity, clinical presentation, epidemiology, and antimicrobial susceptibilities are exceptionally diverse between species. Patients with end-stage lung disease and recipients of lung transplants are at a higher risk of developing NTM colonization and disease and of severe manifestations and outcomes of tuberculosis. Data from the past three decades have increased our knowledge of these infections in lung transplant recipients. Still, there are knowledge gaps to be addressed to further our understanding of risk factors and optimal treatments for mycobacterial infections in this population.

General Overview of Nontuberculous Mycobacteria Opportunistic Pathogens: Mycobacterium avium and Mycobacterium abscessus

Nontuberculous mycobacteria (NTM) are emerging human pathogens, causing a wide range of clinical diseases affecting individuals who are immunocompromised and who have underlying health conditions. NTM are ubiquitous in the environment, with certain species causing opportunistic infection in humans, including Mycobacterium avium and Mycobacterium abscessus. The incidence and prevalence of NTM infections are rising globally, especially in developed countries with declining incidence rates of M. tuberculosis infection. Mycobacterium avium, a slow-growing mycobacterium, is associated with Mycobacterium avium complex (MAC) infections that can cause chronic pulmonary disease, disseminated disease, as well as lymphadenitis. M. abscessus infections are considered one of the most antibiotic-resistant mycobacteria and are associated with pulmonary disease, especially cystic fibrosis, as well as contaminated traumatic skin wounds, postsurgical soft tissue infections, and healthcare-associated infections (HAI). Clinical manifestations of diseases depend on the interaction of the host’s immune response and the specific mycobacterial species. This review will give a general overview of the general characteristics, vulnerable populations most at risk, pathogenesis, treatment, and prevention for infections caused by Mycobacterium avium, in the context of MAC, and M. abscessus.

Non-tuberculous mycobacteria in lung transplant recipients: Prevalence, risk factors, and impact on survival and chronic lung allograft dysfunction

BACKGROUND

Non-tuberculous mycobacteria (NTM) are environmental organisms that colonize or infect lung transplant recipients. Because of differences in populations studied and geographical diversity of species, risk factors for infection and its impact on patient outcomes post transplant are conflicting in the literature.

METHODS

We reviewed the charts of 375 lung transplant recipients at the University of Alberta Hospital (Edmonton, Canada) between 2005 and 2014 to assess NTM epidemiology and risk factors. NTM positivity was determined from a laboratory database. The impact of NTM on patient and graft survival was tested by multivariate Cox regression analysis.

RESULTS

Non-tuberculous mycobacteria were cultured from 26 patients before and 17 patients after transplant. The most commonly isolated species were Mycobacterium avium complex (55%) and Mycobacterium abscessus (20%). Five-year mortality was significantly higher in those infected with NTM after transplant (P = .016), but there was no difference in chronic lung allograft dysfunction (CLAD) at 5 years (P = .999). Cystic fibrosis and lower body mass index were associated with pre-transplant but not post-transplant NTM.

CONCLUSIONS

Isolation of NTM occurred in 7% of patients before and 4.5% of patients after transplant. In this cohort, NTM isolation was associated with increased risk of death but not CLAD onset at 5 years.

Pulmonary Mycobacterium Spindle Cell Pseudotumor in Patient With Liver Transplant

We report a case of liver transplant patient who presented with lung masses, found to be Mycobacterium spindle cell pseudotumors. The masses demonstrated hypermetabolic activities on positron emission tomography. Core biopsy revealed sheets of spindle histiocytic cells with abundant acid-fast bacilli identified as Mycobacterium avium-intracellulare complex. This finding is a rare presentation of Mycobacterium infection, mainly nontuberculous Mycobaterium. It is characterized by a benign, spindle cell mass-forming reaction. Most of the reported cases had acquired immune deficiency syndrome or organ transplant. Histopathology illustrating the proliferation of spindle cell shaped histiocytes containing numerous acid-fast bacilli is the gold standard for diagnosis. The standard treatment has not been well established; previously reported cases followed the standard treatment for Mycobacterium based on organ involvement. Our case is the first case to our knowledge that reports pulmonary Mycobacterium spindle cell pseudotumors in a liver transplant recipient.

Diagnostic and therapeutic approach to infectious diseases in solid organ transplant recipients

Purpose

Prognosis of solid organ transplant (SOT) recipients has improved, mainly because of better prevention of rejection by immunosuppressive therapies. However, SOT recipients are highly susceptible to conventional and opportunistic infections, which represent a major cause of morbidity, graft dysfunction and mortality.

Methods

Narrative review.

Results

We cover the current epidemiology and main aspects of infections in SOT recipients including risk factors such as postoperative risks and specific risks for different transplant recipients, key points on anti-infective prophylaxis as well as diagnostic and therapeutic approaches. We provide an up-to-date guide for management of the main syndromes that can be encountered in SOT recipients including acute respiratory failure, sepsis or septic shock, and central nervous system infections as well as bacterial infections with multidrug-resistant strains, invasive fungal diseases, viral infections and less common pathogens that may impact this patient population.

Conclusion

We provide state-of the art review of available knowledge of critically ill SOT patients with infections.

Mycobacterium avium paratuberculosis and Mycobacterium avium complex and related subspecies as causative agents of zoonotic and occupational diseases

Mycobacterium avium complex (MAC) and Mycobacterium avium paratuberculosis (MAP) cause zoonotic infections transmitted by birds and livestock herds. These pathogens have remained as serious economic and health threats in most areas of the world. As zoonotic diseases, the risk of development of occupational disease and even death outcome necessitate implementation of control strategies to prevent its spread. Zoonotic MAP infections include Crohn's disease, inflammatory bowel disease, ulcerative colitis, sarcoidosis, diabetes mellitus, and immune-related diseases (such as Hashimoto's thyroiditis). Paratuberculosis has classified as type B epidemic zoonotic disease according to world health organization which is transmitted to human through consumption of dairy and meat products. In addition, MAC causes pulmonary manifestations and lymphadenitis in normal hosts and human immunodeficiency virus (HIV) progression (by serotypes 1, 4, and 8). Furthermore, other subspecies have caused respiratory abscesses, neck lymph nodes, and disseminated osteomyelitis in children and ulcers. However, the data over the occupational relatedness of these subspecies is rare. These agents can cause occupational infections in susceptible herd breeders. Several molecular methods have been recognized as proper strategies for tracking the infection. In this study, some zoonotic aspects, worldwide prevalence and control strategies regarding infections due to MAP and MAC and related subspecies has been reviewed.

Mycobacterial Infections in Patients With Chronic Kidney Disease and Kidney Transplantation

Patients with chronic kidney disease have impaired immunity that increases their risk of infection. Increased incidence of mycobacterial infections, in particular Mycobacterium tuberculosis, is described in patients undergoing hemodialysis and peritoneal dialysis as well as after kidney transplantation in low-prevalence and high-prevalence settings. Diagnosis of this infection can be challenging because of atypical presentations that may lead to treatment delay and, consequently, increased mortality; however, recent advances in molecular testing have improved diagnostic accuracy. It is imperative to try to identify those patients at increased risk and offer adequate prophylaxis. There are controversies and insufficient data regarding treatment agents, duration, and dosages. Most studies in nontuberculous mycobacteria are based on case series and retrospective studies.

Respiratory Tract Infections: Sinusitis, Bronchitis, and Pneumonia

Solid organ and hematopoietic stem cell transplant recipients are at increased risk of upper and lower respiratory tract infections. While these infections are frequently encountered in the general population, the spectrum of their clinical presentation including morbidity and mortality is increased in patients undergoing transplantation procedures. Impaired innate and adaptive immunity, potential anatomical abnormalities resulting from extensive surgical procedures, presences of indwelling medical devices, and increased healthcare exposure put transplant recipients at particularly high risk for respiratory tract disease. Infections of the respiratory tract can be divided into those affecting the paranasal sinuses, the upper airways such as bronchitis and tracheobronchitis, and the lower airways like pneumonia. Each of these clinical syndromes can further be classified based on their chronicity, acute vs. chronic; their setting, community vs. nosocomial; and the etiology such as bacteria, viruses, fungi, and rarely parasites. It is also important to realize that such immunologically vulnerable patients are at risk for polymicrobial infection that may present concurrently or in a sequential, consecutive fashion. This chapter reviews the common respiratory tract infections affecting transplant recipients with particular attention directed toward epidemiological risk factors, clinical presentations, diagnostic strategies, and common pathogens. Specific causes of opportunistic pneumonias are also reviewed.

Management of Mycobacterium Other than Tuberculosis in Solid Organ Transplantation

Mycobacteria other than tuberculosis are important pathogens to consider in solid organ transplant recipients. Delay in recognition and treatment may incur significant morbidity and mortality. Management of mycobacteria other than tuberculosis requires a knowledge of treatment specific for each species and drug-drug interactions between antimicrobial and immunosuppressive drugs. Therapy in solid organ transplant can be prolonged and may require a reduction in immunosuppression to improve outcomes.

A rare case of disseminated Mycobacterium avium complex with colitis in a renal transplant recipient

Mycobacterium avium complex (MAC) colitis is a rare complication of immunosuppression in solid organ transplant (SOT) recipients. Here, we describe a case of disseminated MAC infection with colitis following renal transplantation. Despite common pathways of immunosuppression, SOT recipients and human immunodeficiency virus (HIV)-infected patients differ in their typical presentations of MAC infection. Intestinal infections have been more commonly reported in HIV-infected patients than in SOT recipients. The explanation for this difference may be related to HIV's targeted effects on the CD4⁺ T-cell reservoir in gut-associated lymphoid tissue.

Double lung transplantation in an HIV-positive patient with Mycobacterium kansasii infection

Good outcomes with kidney and liver transplantation in HIV-positive patients have led clinicians to recommend lung transplantation in HIV-positive patients based on extrapolated data. Pre-transplant mycobacterial infection is associated with an increased risk of developing new infection or aggravating existing infection, though it does not contraindicate transplantation in non-HIV-infected patients. However, no data exists regarding the outcome of HIV-positive patients with pre-transplant mycobacterial infection. We report a case of double lung transplantation in a 50-year-old HIV-positive patient with alpha-1 antitrypsin deficiency. Prior to transplantation, Mycobacterium kansasii was isolated in one sputum culture and the patient was considered merely colonized as no clinical evidence of pulmonary or disseminated disease was present. The patient successfully underwent a double lung transplantation. Nontuberculous mycobacterial infection was diagnosed histologically on examination of native lungs. Surveillance and watchful waiting were chosen over treatment of the infection. HIV remained under control post-transplantation with no AIDS-defining illnesses throughout the follow-up. A minimal acute rejection that responded to increased corticosteroids was reported. At 12 months post-transplant, a bronchiolitis obliterans syndrome was diagnosed after a drop in FEV1. No evidence of isolation nor recurrence of nontuberculous mycobacteria was reported post-transplantation. At 15 months post-transplant, the patient remained stable with an FEV1 of 30%. The presence of pre-transplant nontuberculous mycobacterial infection did not translate into recurrence of nontuberculous mycobacterial infection post-transplant. Whether it contributed to bronchiolitis obliterans syndrome remains unknown.

Successful Diagnosis of Intestinal Mycobacterium avium Complex Infection in a Kidney Transplant Recipient Using Nasogastric Aspirate Culture: A Case Report

Intestinal Mycobacterium avium complex (MAC) infections are rare and can be challenging to diagnose. We describe a case of intestinal MAC infection in a kidney transplant recipient with 5 months of unexplained weight loss and abdominal pain who developed intestinal obstruction. Esophagoduodenoscopy with biopsies was performed but was nondiagnostic. Intestinal MAC was diagnosed via nasogastric aspirate culture results. The patient's symptoms rapidly improved after initiation of appropriate treatment, but he later died of aspiration pneumonia and candidemia.

How can we improve the outcome for transplant patients with nontuberculous mycobacterial infections?

Nontuberculous mycobacteria (NTM) are environmental organisms that are rapidly emerging as pathogens in the transplant population. The prevalence of infection in transplant recipients remains unknown. While guidelines exist for treatment of NTM, neither the American Thoracic Society, the Infectious Diseases Society of America, nor the British Thoracic Society guidelines dictate the approach needed for transplant recipients. Here, we summarize risk factors, important diagnostic and treatment facts, and preventive measures to be taken to help improve outcomes of those infected with NTM infections.

Infections after lung transplantation

The good clinical result of lung transplantation is constantly undermined by the high incidence of infection, which negatively impacts on function and survival. Moreover, infections may also have immunological interactions that play a role in the acute rejection and in the development of chronic lung allograft dysfunction. There is a temporal sequence in the types of infection that affects lung allograft: in the first postoperative month bacteria are the most frequent cause of infection; following this phase, cytomegalovirus and Pneumocystis carinii are common. Fungal infections are particularly feared due to their association with bronchial complication and high mortality. Scrupulous postoperative surveillance is mandatory for the successful management of lung transplantation patients with respect to early detection and treatment of infections. This paper is aimed to address clinicians in the management of the major infectious complications that affect the lung transplant population.

Non-tuberculous Mycobacterial Infections in Thoracic Transplant Candidates and Recipients

PURPOSE OF REVIEW

To review and discuss the epidemiology, risk factors, clinical presentation, diagnosis, and treatment of non-tuberculous mycobacteria (NTM) in thoracic transplantation.

RECENT FINDINGS

Non-tuberculous mycobacteria are ubiquitous but are an uncommon cause of disease after solid organ transplantation. The incidence of infection is higher in thoracic transplant recipients than in abdominal transplant recipients, with most cases seen after lung transplantation. It is associated with increased morbidity and, occasionally, mortality. Infection in the pre-transplant setting can occur in lung transplant candidates, often posing a dilemma regarding transplant listing. Disease manifestations are diverse, and pulmonary disease is the most common. Diagnosis requires a high index of suspicion. Treatment requires a multiple-drug combination and is limited by drug-drug interactions and tolerability. Mycobacterium abscessus is a challenge in lung transplant recipients, due to its intrinsic resistance and propensity to relapse even after prolonged therapy. Mycobacterium chimaera is an emerging pathogen associated with contamination of heater-cooler units and is described to cause disease months after cardiothoracic surgery. NTM infections in thoracic organ transplant recipients are uncommon but are associated with substantial morbidity and mortality. Data from larger multicenter studies is needed to better define the epidemiology of NTM in thoracic transplantation, best treatment options, and the management of infected transplant candidates.

A case report of fatal disseminated Mycobacterium colombiense infection in a renal transplant recipient

We report the first case of disseminated Mycobacterium colombiense infection in a solid organ transplant recipient. Co-infection with Cryptococcus neoformans led to fatal multisystem organ failure. We review the pathogen and host factors contributing to these opportunistic infections.

Association of Interferon-γ Receptor-1 Gene Polymorphism with Nontuberculous Mycobacterial Lung Infection among Iranian Patients with Pulmonary Disease

Nontuberculous mycobacteria (NTM) cause significant pulmonary infections in humans. Researchers have reported an association between interferon-gamma receptor-1 (IFN-γR1 or IFNGR1) deficiency and susceptibility to NTM, but the relevance of polymorphism within these genes is not yet clear. In this study, a single nucleotide polymorphism (SNP), T to C, at position-56 in NTM patients with pulmonary disease was investigated. Molecular identification of Mycobacterium isolates was performed with hsp65 genes using polymerase chain reaction restriction fragment length polymorphism (PCR-RFLP). Then, the host genomic DNA from confirmed NTM patients (N = 80) and control subjects (N = 80) were screened for SNPs of IFNGR1 (T-56C) by PCR-RFLP. The results indicated that NTM patients had higher TC (26/80; 32.5%) or CC (46/80; 57.5%) genotypes in comparison with control groups (TC genotypes [22/80, 27.5%]; CC genotypes [6/80, 7.5%]) (P < 0.05). In this regard, all the patients infected with rapid-growing Mycobacterium (RGM, i.e., Mycobacterium chelonae and Mycobacterium fortuitum) had CC genotypes (100%). In contrary, only 50.7% (35/69) of infected patients with slow-growing Mycobacterium (i.e., Mycobacterium simiae, Mycobacterium kansasii, and Mycobacterium avium-intracellulare) had CC genotypes. Thus, patients with CC mutation in IFNGR1 at position-56 are more likely to develop RGM infection. In overall, there is a significant association between SNP of IFNGR1 at position-56 and susceptibility to NTM infection. Based on these data, we propose SNP of IFNGR1 at position-56 as a suitable "biomarker" for identifying populations at higher risk of infection.

Epidemiology and Outcomes of Nontuberculous Mycobacterial Infections in Solid Organ Transplant Recipients at a Midwestern Center

BACKGROUND

Nontuberculous mycobacterial (NTM) infections have the potential to affect outcomes in solid organ transplant (SOT) recipients.

METHODS

Retrospective cohort of adults who underwent SOT at a Midwestern hospital between January 1, 2004, and December 31, 2013. NTM-infected patients had at least 1 positive culture for NTM posttransplant. NTM disease was defined by 1) American Thoracic Society/Infectious Disease Society of America criteria for respiratory specimens or 2) NTM cultured from a sterile site with a compatible clinical syndrome. The remaining NTM infected patients were classified as colonized. Cox regression analysis was used to determine the association of NTM with mortality among lung transplant recipients.

RESULTS

Of 3338 SOT recipients, 50 (1.5%) had NTM infection during a median 1038 days (range, 165-3706) follow-up posttransplant. Forty-three patients (86%) with NTM infection were lung transplant recipients; 18 of 43 (41.8%) were treated for NTM and 6 (13.9%) met disease criteria. Isolation of the same species on multiple occasions was associated with treatment among the colonized lung transplant recipients (8/12 [67%] vs 3/25 [12%] who were not treated, P = 0.014). NTM infection was not associated with increased mortality in lung transplant recipients (9/43 [20.9%] in infected died versus 161/510 [31.6%] in uninfected, age-adjusted hazard ratio, 0.56; 95% confidence interval, 0.2-1.1; P = 0.091). Three of 6 lung transplant recipients with NTM disease died compared with 6 of 37 colonized (hazard ratio, 7.0; 95% confidence interval, 1.5-31.5; P = 0.003).

CONCLUSIONS

Among SOT patients, NTM were most frequently identified from lung transplant recipients. NTM infection was not associated with increased mortality, although NTM disease was associated with increased mortality compared with colonization in lung transplant recipients.

Keim oder kein Keim: Herausforderungen bei der Diagnose mykobakterieller Infektionen der Haut

Kutane Mykobakteriosen sind in Deutschland selten. Dennoch ist es für eine frühzeitige Diagnose und anschließende wirksame Behandlung erforderlich, dass diese Krankheitsbilder im ärztlichen Bewusstsein verankert sind. Darüber hinaus stehen Infektionen mit Mykobakterien auf der Liste der Differentialdiagnosen vieler Hautkrankheiten. Diagnosen kutaner Mykobakteriosen beruhen auf klinischen Merkmalen und auf Laboruntersuchungen, einschließlich bakterieller Kulturen, histopathologischer Untersuchungen und PCR-basierten Verfahren. Das Wissen um Möglichkeiten und Grenzen dieser Laboruntersuchungen ist von zentraler Bedeutung, um eine angemessene klinische Entscheidung zu treffen. In diesem Beitrag diskutieren wir die aktuellen diagnostischen Möglichkeiten, die in Verdachtsfällen kutaner Mykobakteriosen zur Verfügung stehen.

Off-label use of the expensive orphan drug eculizumab in France 2009-2013 and the impact of literature: focus on the transplantation field

PURPOSE

The orphan drug eculizumab (Soliris ®) is one of the most expensive in the world and based on expenditures is classed among the highest in France, a scenario suggestive of off-label use. Given its pharmacological properties, it is likely to be used in organ transplantation. Our purposes were to describe the consumption trends of eculizumab for off-label indications overall and in the organ transplantation field and to assess the impact of publications on the latter use.

METHODS

We carried out a temporal ecological study within the French national hospitalization database (PMSI). First, the trend of eculizumab consumption (2009-2013) was compared to our estimate of the maximum on-label consumption (overall and for transplantation). Second, we evaluated the impact of the publications supporting the effectiveness of eculizumab in the transplantation field on temporal trends of eculizumab consumption.

RESULTS

Eculizumab total consumption exceeded our estimate of the maximum on-label consumption since the end of 2011 and increased until the end of the study. The off-label consumption represented at least 50 % of the total consumption. The off-label consumption in organ transplantation also increased since 2011. The amount of publications grew through the study period, but overall, the evidence level remained low. Statistically, publications were neither associated with the drug consumption for transplantation in the long term nor in the short term.

CONCLUSION

Eculizumab started being notably used for off-label indications in France since the end of 2011, and this use increased until the end of the study. We found only low-level evidence concerning the off-label use of eculizumab in the transplantation field through the studied period.

Early onset of nontuberculous mycobacterial pulmonary disease contributes to the lethal outcome in lung transplant recipients: report of two cases and review of the literature

Lung transplant (LuTx) recipients represent a population at risk of nontuberculous mycobacterial pulmonary disease (NTM-PD). Yet the risk factors, the timing of NTM-PD after transplantation, and the association with allograft dysfunction all remain poorly defined. We report 2 cases of early-onset NTM-PD and review the literature, focusing on NTM-PD in LuTx recipients not colonized with NTM prior to transplantation. In addition, we summarize the main characteristics and differences between early- and late-onset disease.

Immune Reconstitution Inflammatory Syndrome Secondary to Mycobacterium kansasii Infection in a Kidney Transplant Recipient

Nontuberculous mycobacteria (NTM) infection is a challenging diagnosis for clinicians in solid organ transplantation. Immune reconstitution inflammatory syndrome (IRIS) is so far unreported in this context. We report here the case of a renal transplant recipient who developed Mycobacterium kansasii-associated lymphadenitis complicated by IRIS while undergoing reduction of his immunosuppressive therapy. For IRIS, the patient required low-dose steroids and an increase in global immunosuppression, in association with NTM antibiotherapy.

Mycobacterial infections in solid organ transplant recipients

Mycobacterial infections represent a growing challenge for solid organ transplant recipients (SOT). The adverse effects of tuberculosis (TB) therapy present a major difficulty, due to the interactions with immunosuppressive drugs and direct drug toxicity. While TB may be donor-transmitted or community-acquired, it usually develops at a latent infection site in the recipient. Pre-transplant prevention efforts will improve transplant outcomes and avoid the complications associated with post-transplant diagnosis and treatment. The present review and consensus manuscript is based on the updated published information and expert recommendations. The current data about epidemiology, diagnosis, new regimens for the treatment of latent TB infection (LTBI), the experience with rifamycins for the treatment of active TB in the post-transplant period and the experience with isoniazid for LTBI in the liver transplant population, are also reviewed. We attempt to provide useful recommendations for each transplant period and problem concerning mycobacterial infections in SOT recipients.

Safety and tolerability of clofazimine as salvage therapy for atypical mycobacterial infection in solid organ transplant recipients

BACKGROUND

The treatment of Mycobacterium avium complex (MAC) requires prolonged, multidrug therapy, which is often not well tolerated. In solid organ transplant (SOT) recipients, drug-drug interactions complicate treatment further. Failure or intolerance requires the use of salvage regimens, and clofazimine is one of the drugs that can be used. No data are available on the safety and tolerability of clofazimine for the treatment of MAC in SOT recipients.

METHODS

Retrospective review of all SOT recipients treated for MAC infection with clofazimine at a large transplant center between 2006 and 2013.

RESULTS

Five SOT recipients received clofazimine as salvage therapy. Transplanted organs were lungs in 3 patients, and kidney and liver in 1 patient each. Infection was diagnosed at a median of 22 months (range 4-57) post transplant. Sites of infection were the lungs in 2 patients, and septic arthritis, mesenteric, and disseminated disease in 1 patient each. All patients received standard anti-MAC therapy for a median of 26 weeks (range 18-45) before starting clofazimine. Indications for use of clofazimine included a lack of response to previous therapy (3 patients), and poor tolerance of other regimens (3 patients). All patients received at least 2 additional drugs besides clofazimine. Median duration of clofazimine-containing regimen was 8 months (range 2-18). Clofazimine was discontinued because of gastrointestinal intolerance in 1 of the 5 patients. The most common adverse event from clofazimine was skin discoloration, in 60% of patients. No hepatotoxicity or hematologic toxicity occurred. Microbiological clearance and resolution of clinical disease was documented in 2 of 5 patients; and 2 of the 5 patients died of other causes while on therapy.

CONCLUSIONS

Clofazimine appears safe and may be considered as a salvage therapeutic option in SOT recipients with MAC infection who are intolerant or unresponsive to standard therapy. The small sample size does not allow conclusions regarding efficacy.

Skin and soft tissue infections caused by nontuberculous mycobacteria

PURPOSE OF REVIEW

Skin and soft tissues infections (SSTIs) caused by nontuberculous mycobacteria (NTM) are underrecognized and difficult to treat. Controversies exist for optimal medical management and the role of surgery. Defining the epidemiology in the environment, in animals and in healthcare aids disease prevention. This review focuses on recent advances in epidemiology, risk factors, diagnostics and therapy.

RECENT FINDINGS

The increasing consumer appetite for cosmetic and body-modifying procedures (e.g. tattooing, mesotherapy, liposuction) has been associated with rises in sporadic cases and outbreaks of NTM SSTIs. In mainstream healthcare, recent epidemiological studies have helped to quantify the increased risk of NTM infection related to anti-tumour necrosis factor-α monoclonal antibody therapy. Cervicofacial lymphadenitis in children poses management dilemmas, but recent studies and resultant algorithms have simplified decision-making. Molecular studies have led to a better understanding of the epidemiology, therapy and course of Mycobacterium ulcerans infection (Buruli ulcer) that remains prevalent in many areas including sub-Saharan Africa and southeastern Australia. Apart from molecular methods, the widespread adoption of matrix-assisted laser desorption ionization-time of flight mass spectrometry by routine laboratories has potential to simplify and expedite the laboratory identification of NTMs.

SUMMARY

An improved understanding of the epidemiology of NTM SSTIs indicates a need to apply effective infection control and ensure regulation of cosmetic and related procedures associated with nonsterile fluids. Broader access to newer diagnostic methods will continue to improve recognition of NTM disease. Along with a paucity of therapeutic agents, there is need for more reliable methods to assess susceptibility and selection of effective combination therapy.

Highlight on advances in nontuberculous mycobacterial disease in North America

Nontuberculous mycobacteria (NTM) are ubiquitous in the environment and exist as an important cause of pulmonary infections in humans. Pulmonary involvement is the most common disease manifestation of NTM and the incidence of NTM is growing in North America. Susceptibility to NTM infection is incompletely understood; therefore preventative tools are not well defined. Treatment of pulmonary nontuberculous mycobacterial (NTM) infection is difficult and entails multiple antibiotics and an extended treatment course. Also, there is a considerable variation in treatment management that should be considered before initiating treatment. We highlight the new findings in the epidemiology diagnosis and treatment of mycobacterial infections. We debate new advances regarding NTM infection in cystic fibrosis patients and solid organ transplant recipients. Finally, we introduce a new epidemiologic model for NTM disease based on virulence-exposure-host factors.

A case of Mycobacterium mucogenicum infection in a liver transplant recipient and a review of the literature

Bacterial, viral, and fungal infections can be devastating in a postoperative liver transplant recipient on multidrug immunosuppressive therapy. Various atypical (nontuberculous mycobacteria [NTM]) mycobacterial infections have been reported in the solid organ transplant population, but to our knowledge, no cases of Mycobacterium mucogenicum infections have been reported. Here, we report a case of a patient with end-stage liver disease secondary to primary biliary cirrhosis, model for end-stage liver disease score of 29, who underwent deceased-donor orthotopic liver transplantation, with her postoperative course complicated by multiple pleural effusions and peritonitis. Despite numerous courses of antibiotics, her condition did not improve. Acid-fast bacilli cultures grew M. mucogenicum, which was then treated with appropriate antimicrobical therapy. M. mucogenicum, a rapidly growing NTM that can be present in water contamination, should be recognized as a potential source of infection, especially in the immunocompromised population.