Tuberculosis After Heart Transplantation: Twenty Years of Experience in a Single Center in Taiwan

Prevention and management of tuberculosis in solid organ transplantation: A consensus statement of the transplantation society of Taiwan

Solid organ transplant recipients have an increased risk of tuberculosis (TB). Due to the use of immunosuppressants, the incidence of TB among solid organ transplant recipients has been consistently reported to be higher than that among the general population. TB frequently develops within the first year after transplantation when a high level of immunosuppression is maintained. Extrapulmonary TB and disseminated TB account for a substantial proportion of TB among solid organ transplant recipients. Treatment of TB among recipients is complicated by the drug-drug interactions between anti-TB drugs and immunosuppressants. TB is associated with an increased risk of graft rejection, graft failure and mortality. Detection and management of latent TB infection among solid organ transplant candidates and recipients have been recommended. However, strategy to mitigate the risk of TB among solid organ transplant recipients has not yet been established in Taiwan. To address the challenges of TB among solid organ transplant recipients, a working group of the Transplantation Society of Taiwan was established. The working group searched literatures on TB among solid organ transplant recipients as well as guidelines and recommendations, and proposed interventions to strengthen TB prevention and care among solid organ transplant recipients.

Infections in Heart, Lung, and Heart-Lung Transplantation

Half a century has passed since the first orthotopic heart transplant took place. Surgical innovations allowed for heart, lung, and heart-lung transplantation to save lives of patients with incurable chronic cardiopulmonary conditions. The complexity of the surgical interventions, chronic host health conditions, and antirejection immunosuppressive medications makes infectious complications common. Infections have remained one of the main barriers for successful transplantation and a source of significant morbidity and mortality. Recognition of infections and its management in this setting require outstanding clinical skills since transplant recipients may not exhibit classic signs or symptoms of disease, and laboratory work has some pitfalls. The prevention, identification, and management of infectious diseases complications in this population are a priority to undertake to improve the medical outcomes of transplantation. Herein, we reviewed the historical aspects, epidemiology, and prophylaxis of infections in heart, lung, and heart-lung transplantation. We also discuss the most prevalent organisms affecting the host and the organ systems involved.

Treatment of tuberculosis infection complicated with liver transplant

Liver transplant is considered the best choice for treating various end-stage liver diseases either at home or abroad. Among patients of liver transplant complicated with tuberculosis (TB), the incidence and mortality of postoperative active TB are bound to increase remarkably. Diagnosing and treating TB in patients with end-stage liver diseases who received immunosuppressants after liver transplant are difficult because of the absence of specific clinical manifestations while being complicated with TB, reduced sensitivity to cellular immunoassay, and interaction between anti-TB drugs and immunosuppressants. Therefore, the screening of high-risk groups, improvement in diagnostic accuracy, preoperative treatment, and reduced interaction between anti-TB drugs and immunosuppressants can help optimize diagnosis and treatment regimes and thus further improve the prognosis of patients.

Tuberculosis and Transplantation

Mycobacterium tuberculosis is a major opportunistic pathogen in transplant recipients. Compared to that in the general population, the frequency of tuberculosis (TB) is 10 to 40 times higher in hematopoietic stem cell transplant (HSCT) recipients and 20 to 74 times higher in solid-organ transplant (SOT) recipients. Transplant recipients with TB are also more likely to develop disseminated disease, have longer time to definitive diagnosis, require more invasive diagnostic procedures, and experience greater anti-TB treatment-related toxicity than the general population. Specific risk factors for TB in SOT recipients include previous exposure to M. tuberculosis (positive tuberculin skin tests and/or residual TB lesions in pretransplant chest X ray) and the intensity of immunosuppression (use of antilymphocyte antibodies, type of basal immunosuppression, and intensification of immunosuppressive therapy for allograft rejection). Risk factors in HSCT recipients are allogeneic transplantation from an unrelated donor; chronic graft-versus-host disease treated with corticosteroids; unrelated or mismatched allograft; pretransplant conditioning using total body irradiation, busulfan, or cyclophosphamide; and type and stage of primary hematological disorder. Transplant recipients with evidence of prior exposure to M. tuberculosis should receive treatment appropriate for latent TB infection. Optimal management of active TB disease is particularly challenging due to significant drug interactions between the anti-TB agents and the immunosuppressive therapy. In this chapter, we address the epidemiology, clinical presentation, diagnostic considerations, and management strategies for TB in SOT and HSCT recipients.

Mycobacterium tuberculosis infection in transplant recipients: early diagnosis and treatment of resistant tuberculosis

PURPOSE OF REVIEW

To provide a better understanding and summarize recent advances in the diagnosis and treatment of Mycobacterium tuberculosis (MTB) infection in solid organ transplant (SOT) candidates and recipients.

RECENT FINDINGS

Despite advances in SOT medicine, MTB causes substantial morbidity and mortality in SOT recipients, with reported prevalence rates of 0.4-6%. The primary source of posttransplant MTB is reactivation of pretransplant latent MTB infection. The short-term mortality rate in SOT recipients with drug-susceptible active MTB is 30%. In immunocompromised persons with extensively drug-resistant MTB, the mortality rate approaches 100%. Clinical presentation is often atypical with more than half of SOT recipients presenting with extrapulmonary or disseminated disease. Pretransplant latent MTB infection screening and treatment is the cornerstone for preventing reactivation and dissemination of active MTB posttransplant. Treatment of active MTB in SOT recipients is problematic, given significant drug toxicity and interaction with immunosuppressive agents.

SUMMARY

A high degree of suspicion for latent and active MTB infection in SOT candidates and recipients is warranted to establish a timely diagnosis and initiate life-saving appropriate therapy.

Respiratory infections in immunocompromised patients

PURPOSE OF REVIEW

Immunosuppressive states and therapies are becoming common in clinical practice. Recent advances and trends in bacterial, fungal, viral and parasitic pulmonary infections in immunosuppressed patients are described.

RECENT FINDINGS

Pulmonary infections can jeopardize the prognosis of immunosuppressed patients. The number of patients infected with multidrug-resistant bacteria or opportunistic pathogens like rapid-growing environmental mycobacteria, Strongyloides stercoralis or Rhodococcus equi is increasing with the increased numbers of immunosuppressed patients due to HIV/AIDS and the potent immunosuppressive therapies used in solid-organ and haematopoietic transplantations, cancer and systemic illnesses. The slow development of more effective antibiotics underlines the necessity of preventive measures, development of rapid detection tests for pathogens and appropriate treatment regimens to avoid development of further resistance.

SUMMARY

Adequate prophylaxis, clinical suspicion, microbiological and molecular investigations, drug susceptibility-based antibiotic treatment and new drug development are strategies required to face up to the challenge of pulmonary infections in immunodepressed patients.