Latent tuberculosis: Risk factors, screening and treatment in liver transplantation recipients from an endemic area

Screening for Latent Tuberculosis Infection in Solid Organ Transplant Recipients to Predict Active Disease: A Systematic Review and Meta-Analysis of Diagnostic Studies

BACKGROUND

This is a systematic review and meta-analysis of diagnostic test accuracy studies to assess the predictive value of both tuberculin skin test (TST) and interferon-gamma release assays (IGRA) for active tuberculosis (TB) among solid organ transplantation (SOT) recipients.

METHODS

Medline, Embase, and the CENTRAL databases were searched from 1946 until June 30, 2022. Two independent assessors extracted data from studies. Sensitivity analyses were performed to investigate the effect of studies with high or low risk of bias. Methodological quality of each publication was assessed using QUADAS-2.

RESULTS

A total of 43 studies (36 403 patients) with patients who were screened for latent TB infection (LTBI) and who underwent SOT were included: 18 were comparative and 25 noncomparative (19 TST, 6 QuantiFERON-TB Gold In-Tube [QFT-GIT]). For IGRA tests taken together, positive predictive value (PPV) and negative predictive value (NPV) were 1.2% and 99.6%, respectively. For TST, PPV was 2.13% and NPV was 95.5%. Overall, PPV is higher when TB burden is higher, regardless of test type, although still low in absolute terms. Incidence of active TB was similar between studies using LTBI prophylaxis (mean incidence 1.22%; 95% confidence interval [CI], .2179-2.221) and those not using prophylaxis (mean incidence 1.045%; 95% CI, 0.2731-1.817; P = .7717). Strengths of this study include the large number of studies available from multiple different countries; limitations include absence of gold standard for diagnosis of latent TB and low incidence of active TB.

CONCLUSIONS

We found both TST and IGRA had a low PPV and high NPV for the development of active TB posttransplant. Further studies are needed to better understand how to prevent active TB in the SOT population.

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.

The prevalence of latent/chronic infection in liver transplant candidates in Taleghani Hospital of Tehran, Iran, from 2020 until 2021

Aim

The present study aimed to study the prevalence of various latent infections in pre-transplanted patients.

Background

Due to chronic immunosuppressive therapy, patients receiving organ transplants are at risk for reactivation of various infections. Due to the complications in the course of diagnosing and treating the post-transplant infection, screening transplant recipients and donors is vital.

Methods

This retrospective cohort study was performed between March 2020 and 2021. A total of 193 patients receiving a liver transplant in Taleghani Hospital, Tehran, Iran were enrolled.

Results

One-hundred and three (53.4%) patients were men, with an average age of 48.4 ± 13.3 years. Among viruses, 177 (91.7%) patients had a positive IgG titer for CMV. Anti-EBV IgG was positive in 169 (87.6%) patients. One-hundred and seventy-five (90.7%) patients had a positive IgG titer for the VZV. One-hundred and sixty-six (86.0%) cases had positive IgG anti-HSV antibodies. According to our findings, none of the patients were infected with HIV, but 9 (4.7%) cases and 141 (73.1%) had positive anti-HCV and anti-HAV IgG antibodies, respectively. HBV surface (HBs) antigen was also reported positive in 17 (8.8%) patients, while the HBs antibody was positive in 29 (15.0%) patients.

Conclusion

In our study, most of the patients had positive serology for latent viral infections such as CMV, EBV, VZV, and HSV, but the prevalence of latent tuberculosis and viral hepatitis was low among transplant candidates.

Isoniazid prophylaxis in liver transplant recipient with latent tuberculosis; Is it harmful for transplanted liver?

BACKGROUND

Liver transplantation (LT) is considered the only treatment for patients with end-stage liver disease and, despite its incredible impacts on the patients' health status, places them in an immunocompromised state in which opportunistic infection would find a way to present. Latent Tuberculosis Infection (LTBI) is the most common form of TB and can be diagnosed through Tuberculin Skin Test (TST) or Interferon-Gamma Release Assays (IGRA). LT recipients are at significant risk of TB activation. There is no strict guideline to approaching these cases though, in most centers, Isoniazid (INH) would be prescribed prophylactically. INH is a hepatotoxic medication and can have adverse effects on the transplanted liver. There is no consensus on this issue; therefore, we aimed to survey the potential hepatotoxic effects of INH among LT recipients in Shiraz, Iran.

METHODS

A retrospective cohort study was conducted among LT candidates and recipients at Abu Ali Sina Organ Transplantation Center between 1993 and 2019. All the cases underwent TST and chest X-ray to detect LTBI. All the LTBI were treated with INH from six to nine months and followed by the level of liver enzymes for quick detection of hepatotoxicity. A control group was selected among LT recipients and matched for age, gender, MELD score, and donor age.

RESULTS

Among 4895 medical records reviewed, 55 (1.12%) cases had LTBI. Neither INH-related hepatotoxicity, nor signs and symptoms that were suspicious to TB reactivation were reported. Overall, three deaths were reported, two because of myocardial infarction and one due to pneumonia. Ten patients (18.2%) experienced acute rejection as confirmed with pathology and responded to methylprednisolone. Aspartate aminotransferase (AST) was diminished from pre-LT time to the first time after transplantation; after that, it showed a steady pattern. Meanwhile, Alanine transaminase (ALT) was constant before and one stage later and decreased after that. Statistical analyses only showed significant changes in the total bilirubin titer between the case and control groups.

CONCLUSION

This survey showed prophylactic management of LTBI with INH in LT candidates and recipients was associated with no hepatotoxicity or related death. It seems INH prophylaxis is safe in LT settings and can efficiently prevent TB activation; however, careful monitoring for adverse effects and liver enzymes elevation is highly recommended. This article is protected by copyright. All rights reserved.