Treatment of latent TB Infection and the risk of tuberculosis after solid organ transplantation: Comprehensive review

Analysis of Indeterminate QuantiFERON Assay Results in Solid Organ Transplant Candidates and Proposed Management Algorithm

BACKGROUND

Identification and treatment of latent tuberculosis infection (LTBI) mitigate the risk of tuberculosis (TB) reactivation after transplantation. TB reactivation is higher in those with indeterminate QuantiFERON (QFT) than those with negative results. Management of indeterminate QFT results in the pretransplant period remains unclear.

METHODS

We conducted a retrospective study of solid organ transplant (SOT) recipients, 18 y and older, who were screened with QFT assay pretransplantation at Mayo Clinic between January 2010 and June 2023. We examined the frequency of indeterminate QFT results, results of repeat LTBI screening, treatment decisions, and rate of posttransplant TB infection.

RESULTS

Of 13 008 patients screened for LTBI before SOT, 736 (6%) patients had indeterminate QFT results. Among these, 247 (34%) underwent a second LTBI screening test, and 39 (5%) received LTBI treatment. Among 247 patients with a repeat LTBI screening test, 185 (75%), 48 (19%), and 14 (6%) were tested by QFT, T-SPOT.TB, or TST, respectively. The repeat QFT remained indeterminate in 160 (86%) patients, whereas all T-SPOT.TB results were negative. Posttransplant TB infection occurred in 2 (0.3%) patients; neither had a second TB screening test pretransplant nor received LTBI treatment.

CONCLUSIONS

In SOT recipients with indeterminate QFT results at pretransplant evaluation, opting for T-SPOT.TB as a second test may be preferable over repeat QFT. TB infection after transplantation in patients with a pretransplant indeterminate QFT result was rare. Patient management and LTBI treatment in those with indeterminate QFT pretransplant should account for epidemiological risk factors, and shared decision-making is recommended.

Infectious Disease Prophylaxis During and After Immunosuppressive Therapy

Immune-mediated renal diseases are a diverse group of disorders caused by antibody, complement, or cell-mediated autosensitization. Although these diseases predispose to infection on their own, a growing array of traditional and newer, more targeted immunosuppressant medications are used to treat these diseases. By understanding their mechanisms of action and the infections associated with suppression of each arm of the immune system, nephrologists can better anticipate these risks and effectively prevent and recognize opportunistic infections. Focusing specifically on nonkidney transplant recipients, this review discusses the infections that can be associated with each of the commonly used immunosuppressants by nephrologists and suggest interventions to prevent infectious complications in patients with immune-mediated renal disease.

The Cascade of Care in Management of Solid Organ Transplant Candidates With Latent Tuberculosis Infection

Background

Solid organ transplant (SOT) candidates should be screened and treated for latent tuberculosis infection (LTBI) to prevent tuberculosis (TB) reactivation after transplantation. We aimed to assess the steps from positive QuantiFERON (QFT) through LTBI treatment (cascade of care) in the SOT population.

Methods

We conducted a retrospective study of SOT recipients older than 18 y with a positive QFT during pretransplant evaluation at the Mayo Clinic from January 2010 to June 2023. We analyzed each cascade step to determine associated drop-out factors for LTBI management.

Results

Of 629 patients who had positive QFT results, 587 (93%) were evaluated by an infectious disease (ID) specialist, 478 (76%) were recommended to start LTBI treatment, 473 (75%) initiated LTBI treatment, and 457 (73%) completed LTBI treatment. LTBI treatment was not recommended in 109 patients evaluated by infectious disease, most of whom had previously received either LTBI (n = 72) or TB (n = 14) treatment. LTBI treatment was initiated before or after transplantation for 45% and 55% of patients, respectively. Isoniazid monotherapy was the most common regimen (92%), and adverse events were rare (7%). Seven patients developed active TB infection posttransplantation under various circumstances (3 without LTBI treatment, 1 during LTBI treatment, and 3 after completing LTBI treatment).

Conclusions

Our findings demonstrate the variability of LTBI management in SOT recipients with positive QFT. When recommended, most patients completed LTBI treatment successfully. Nonetheless, active TB was noted regardless of whether patients received LTBI treatment. This study highlights the importance of optimizing LTBI management in this population.

Characteristics, management, and outcome of tuberculosis after liver transplant: A case series and literature review

BACKGROUND

Liver transplant recipients are at risk of tuberculosis, which is particularly difficult-to diagnose and to treat in this population.

METHODS

Retrospective study of all cases of tuberculosis diagnosed from 2007 to 2022 in the French network of liver transplant sites.

RESULTS

Twenty-three liver transplant recipients were diagnosed with tuberculosis (six females, median age 59 years [interquartile range, 54-62]), with a median time lapse of 10 months [5-40.5] after transplant, and 38 days [26-60] after symptoms onset. Primary modes of pathogenesis were latent tuberculosis reactivation (n = 15) and transplant-related transmission (n = 3). Even though most patients with pre-transplant data had risk factors for tuberculosis (11/20), IFN-gamma release assay was performed in only three. Most cases involved extra-pulmonary tuberculosis (20/23, 87 %). With median follow-up of 63 months [24-108], five patients died (22 %), including four tuberculosis-related deaths.

CONCLUSIONS

Extrapulmonary tuberculosis is a severe disease in liver transplant recipients. Systematic pre-transplant screening of latent tuberculosis may prevent most of them.

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.

South Asian Transplant Infectious Disease Guidelines for Solid Organ Transplant Candidates, Recipients, and Donors

These guidelines discuss the epidemiology, screening, diagnosis, posttransplant prophylaxis, monitoring, and management of endemic infections in solid organ transplant (SOT) candidates, recipients, and donors in South Asia. The guidelines also provide recommendations for SOT recipients traveling to this region. These guidelines are based on literature review and expert opinion by transplant physicians, surgeons, and infectious diseases specialists, mostly from South Asian countries (India, Pakistan, Bangladesh, Nepal, and Sri Lanka) as well as transplant experts from other countries. These guidelines cover relevant endemic bacterial infections (tuberculosis, leptospirosis, melioidosis, typhoid, scrub typhus), viral infections (hepatitis A, B, C, D, and E; rabies; and the arboviruses including dengue, chikungunya, Zika, Japanese encephalitis), endemic fungal infections (mucormycosis, histoplasmosis, talaromycosis, sporotrichosis), and endemic parasitic infections (malaria, leishmaniasis, toxoplasmosis, cryptosporidiosis, strongyloidiasis, and filariasis) as well as travelers' diarrhea and vaccination for SOT candidates and recipients including travelers visiting this region. These guidelines are intended to be an overview of each topic; more detailed reviews are being published as a special supplement in the Indian Journal of Transplantation .

Mycobacteria in Organ Transplant Recipients

This review describes the epidemiology and risk factors of tuberculosis (TB) in solid organ transplant recipients. We discuss the pre-transplant screening for risk of TB and management of latent TB in this population. We also discuss the challenges of management of TB and other difficult to treat mycobacteria such as Mycobacterium abscessus and Mycobacterium avium complex. The drugs for the management of these infections include rifamycins which have significant drug interactions with immunosuppressants and must be monitored closely.

The cascade of care in testing and treatment of latent tuberculosis infection in liver transplant candidates

BACKGROUND

Testing and treatment for latent tuberculosis infection (LTBI) can mitigate risk of active tuberculosis (TB) post-liver transplant (LT). Testing and treatment completion rates have been reported low in this population. Our study aims to quantify the proportion of LT candidates who completed LTBI care cascade in our center.

METHODS

A retrospective chart review was conducted on LT candidates from 2012 to 2021. Primary outcome was the proportion of patients who completed each cascade stage. Secondary outcome was an analysis of factors associated with positive and indeterminate LTBI testing.

RESULTS

Of the 273 LT candidates, 265 (97.1%) were referred to transplant infectious disease (TID), 264 (96.7%) had orders for interferon-gamma release assay (IGRA), 262 (96%) underwent TID evaluation, and 259 (94.9%) completed IGRA. Twenty had LTBI, and 18 were treatment naïve and recommended for treatment. Of the 18, 15 (83.3%) agreed to therapy, 14 (77.8%) initiated treatment, and 12 (66.7%) completed treatment. No posttransplant TB reactivation occurred. Patients born in Asia, previous incarceration, past military service, and granuloma findings on chest imaging were likely to have positive IGRA (p < .05). Older age and travel to TB-endemic countries were likely to have indeterminate IGRA (p < .05). Indeterminate IGRAs were more common in QuantiFERON (QTF)-Gold Plus TB (15.3%) versus QTF-Gold TB (9.3%, p < .001).

CONCLUSIONS

High rates of LTBI testing and treatment initiation and completion can be attributed to a standardized process that includes TID evaluation. Future studies in larger cohort are needed to better understand factors that can optimize the completion rates of LTBI treatment in LT candidates.

Risk Groups of Developing Active Tuberculosis in Liver Transplant Recipients in a Tuberculosis Endemic Area: Risk Stratification by Chest Image and Interferon Gamma Release Assay

OBJECTIVES

We implemented a stratified risk analysis to predict the development of active tuberculosis (TB) in liver transplantation (LT) recipients based on IGRA and chest images in a TB-endemic area.

METHODS

In this retrospective cohort study, LT recipients who tested for IGRA between May 2008 and December 2017 were included. Chest images compatible with old TB lesions were considered as positive images. LT recipients were divided into six groups: LT recipients with history of treated TB, image (+)/IGRA (+), image (+)/IGRA (-), image (-)/IGRA (+), image (-)/IGRA (-) and LTBI treated. The Cox regression model was used to analyze risk groups.

RESULTS

Among the 717 eligible LT recipients included in this study, 21 patients developed active TB. Incidence rates of TB were 2,261, 724, and 119 cases/100,000 person-years in the 1st, 2nd, and ≥ 3rd year after transplantation, respectively. History of treated TB (HR 18.92; 95% CI 4.10-87.25) and image (+)/IGRA (+) (HR 10.86; 95% CI 2.75-42.89) were independent risk factors for developing active TB. IGRA (+) with a negative image was not a risk factor.

CONCLUSIONS

Our findings suggested that both IGRA and chest images should be considered to identify risk groups for LTBI treatment.

Mycobacterium tuberculosis in solid organ transplant donors and recipients

PURPOSE OF REVIEW

Due to impaired immune response, solid organ transplant (SOT) recipients are susceptible to tuberculosis (TB) and its subsequent morbidity and mortality. Current prevention strategies, diagnostic and treatment approach to TB infection in donors and recipients were reviewed in this article.

RECENT FINDINGS

Screening of latent tuberculosis infection (LTBI) in donors and recipients is the cornerstone of TB-preventive strategy in recipients and requires an assessment of TB risk factors, TB-specific immunity testing, and radiographic evaluation. Interferon-gamma release assay has superseded the tuberculin skin test in LTBI evaluation despite its recognized limitations. LTBI treatment should be offered to transplant candidates and living donors before transplantation and donation, respectively. Diagnosis of TB disease can be challenging because of nonspecific clinical presentation in the recipient and is limited by the sensitivity of current diagnostics. The approach to LTBI and TB disease treatment is similar to the general population, but can be challenging because of potential drug interactions and toxicities.

SUMMARY

The appropriate evaluation of donors and recipients for TB can mitigate posttransplant TB disease. Current approaches to diagnosis and treatment parallels that of immunocompetent hosts. Future research evaluating existing and novel diagnostics and treatment in transplant recipients is needed.

Donor-Derived Tuberculosis: A Case Report and the Role of Communication Gaps in Transplantation Safety

Donor-derived tuberculosis (DD-TB) accounts for less than 5% of TB cases and is considered a rare event. In the transplant setting, the frequency of active TB is estimated to be 20 to 74 times higher than that in the general population, and it is associated with high mortality. In this context, the main strategy to minimize the risk of DD transmission is to identify high-risk donors. Despite screening recommendations, failures may result in a breakdown of safety that ends in the transmission of potentially fatal diseases. This report describes a case of DD-TB and emphasizes communication gaps that may occur between organ procurement organizations and transplant centers. Failure in reporting results, lack of exchanging information regarding recipients from the same donor, and inefficient communication between organ procurement organizations and transplant centers are lacks that may be prevented by a more efficient approach towards screening protocols and communication.

Multifocal skeletal tuberculosis with mycobacteremia after kidney transplantation: A case report

Solid organ transplant recipients have a higher risk of active Mycobacterium tuberculosis infection (TB) compared to the general population. Recognized risk factors are immunosuppressant use, graft dysfunction, diabetes mellitus, liver disease caused by the hepatitis C virus, and co-infections by other opportunists. Most of the active TB cases reported in solid organ transplant recipients occur in kidney transplant patients, especially if they come from M tuberculosis-endemic areas. Extrapulmonary and disseminated TB are among the wide spectrum of clinical presentations found, but the lungs are the most common organ affected. Disseminated disease occurs in up to a third of the affected population, however, multifocal osteoarticular TB with mycobacteremia is unusual. We report the case of a kidney transplant patient with disseminated M tuberculosis infection, who presented with multifocal skeletal TB.

The paradigm shift in the approach to management of latent tuberculosis infection in high tuberculosis burden countries

Introduction: Addressing the reservoir of Latent Tuberculosis Infection (LTBI) is critical to TB elimination because if left untreated LTBI can progress to active TB disease. This additional burden can prevent achieving the global targets of TB elimination. Management of LTBI has been a low priority target for National TB Elimination Programs (NTEP) due to various challenges in the field settings.Areas covered: This article reviews the most recent advances in the field of LTBI management including newer diagnostics, treatments, vaccines, programmatic challenges, and gaps and suggests a way forward that can be adopted by NTEPs for LTBI. We searched the electronic databases of PubMed, Scopus, and Web of Science for studies published between 2010 to 2020 using MeSH terms: Latent TB Diagnosis, TB preventive therapy, Vaccines, LTBI, and HIV/ COVID.Expert opinion: NTEPs of developing countries should offer a better, point-of-care diagnostic, and effective treatment for LTBI to reduce the number of new TB cases arising from people infected with M.tb. Awareness about LTBI should be increased among the health system staff and the public. More funding is needed to advance research as well as implement the newer findings in the NTEP to achieve the End TB targets by 2035.

Risk factors and clinical outcomes of tuberculosis among kidney transplant recipients in high endemic country

BACKGROUND

Tuberculosis (TB) is considered as a challenge issue in solid organ transplant recipients because of high morbidity and mortality. Active TB after transplant mostly occurs from reactivation of latent infection. Understanding risk factors and clinical information of TB may provide an appropriate prevention and treatment strategies in this specific patient population, however data from high endemic area is scarce.

METHODS

A matched single-center, case-control study was conducted in our institute. Cases were defined as newly diagnosed confirmed or clinical active TB in patients who underwent kidney transplant (KT) between April 1992 and October 2018. For each case, 5 controls were matched by age and sex. Risk factor associated with TB was determined using univariate and multivariate conditional logistic regression.

RESULTS

Between study period, KT was performed in 787 patients. Twenty-seven patients (3.43%) were diagnosed with active TB including 20 confirmed and 7 clinical diagnosed cases. The global incidence of TB in our population was 315 cases per 100 000 patients per year. Among 27 cases, pulmonary involvement was the most common (48.1%) followed by disseminated (18.5%), extrapulmonary (14.8%), pleura (11.1%) and pleuropulmonary (7.4%) TB. Allograft rejection was significantly associated with active TB (P < .001). The median onset duration of infection was 17 months (IQR, 4-59 months) after KT. Twenty-four (88.9%) patients received rifampicin containing regimen for treatment with median duration of 10 months (IQR, 6-12 months). All patients were cured after complete treatment, however those with TB remained having unfavorable outcomes including higher all-cause mortality and graft loss.

CONCLUSIONS

Incidence rate of TB in KT recipients is higher than normal population. Allograft rejection was identified as a significant risk factor. Increase unfavorable outcomes including graft loss and mortality were also observed among patients with TB.

Prevention and treatment of tuberculosis in solid organ transplant recipients

Introduction: Tuberculosis (TB) in solid organ transplant (SOT) recipients is associated with significant morbidity and mortality. Its management in transplant recipients is difficult and highly complex, given the underlying immunosuppression and the risks of drug-drug interactions imposed by immunosuppressive drugs that are needed to maintain the transplant allograft.Areas covered: We provide a brief review of TB in SOT and discuss the clinical indications, mechanisms of action and drug resistance, drug-drug interactions, and adverse effects of anti-TB drugs. We provide a summary of recent clinical trials, which serve as the foundation for current recommendations. We further include relevant updates on new agents being evaluated for clinical use in TB management.Expert commentary: TB causes significant morbidity in SOT recipients. The drugs used in the treatment for latent TB and active disease in SOT are similar to the regimens used in the general population. However, TB disease in transplant recipients is more difficult to manage because of the potential for hepatotoxicity and the complex drug-drug interactions with immunosuppressive drugs. We believe that alternative regimens suited for the vulnerable transplant population, and more therapeutic drug options are needed given the adverse toxicities associated with currently approved anti-TB drugs.