Comparison of Tuberculosis Infection Rates in a National Database of Renal Transplant Patients With Data From a Single Center in Taiwan

Identification of immune-associated genes involved in latent Mycobacterium marinum infection

Tuberculosis (TB) is a high mortality infectious disease caused by Mycobacterium tuberculosis (Mtb), and often develops into latent infection. About 5～10% of latent infections turn into active tuberculosis when the host immune system becomes deficient. Therefore, exploring the latent infection mechanism of Mtb is pivotal for the prevention and treatment of tuberculosis. We first established the zebrafish latent infection model and the chronic infection model utilizing Mycobacterium marinum, which has the highly similar gene background to Mtb. Using the latent infection model, we characterized the gene expression profiles and found 462 genes expressed differentially in the latent period and chronic tuberculosis infection. These differentially expressed genes are involved in various biological processes including transcription, transcriptional regulation, organism development, and immune responses. Among them, nineteen immune-related genes were found to express differentially in the latent period. By analyzing immune related protein network, the genes in the center of the network, including Nos2b, TNFα, IL1, TNFβ, TLR1, TLR2, and TLR4b, displayed significant deferential expression in latent infection and chronic infection period of zebrafish, suggesting that these genes might play an important role in controlling latent infection of Mtb. Identifying immune biomarker related to the status of tuberculosis latent infection might lead to novel strategy for diagnosis and treatment.

Immunopathology of lung transplantation: from infection to rejection and vice versa

Lung transplantation offers a lifesaving option for patients with end-stage lung disease, but it is marred by a high risk of post-transplant infections, particularly involving multidrug-resistant bacteria, Cytomegalovirus, and fungal pathogens. This elevated infection rate, the highest among solid organ transplants, poses a significant challenge for clinicians, particularly within the first year post-transplantation, where infections are the leading cause of mortality. The direct exposure of lung allografts to the external environment exacerbates this vulnerability leading to constant immune stimulation and consequently to an elevated risk of triggering alloimmune responses to the lung allograft. The necessity of prolonged immunosuppression to prevent allograft rejection further complicates patient management by increasing susceptibility to infections and neoplasms, and complicating the differentiation between rejection and infection, which require diametrically opposed management strategies. This review explores the intricate balance between preventing allograft rejection and managing the heightened infection risk in lung transplant recipients.

Impact of the pretransplant dialysis modality on kidney transplantation outcomes: a nationwide cohort study

OBJECTIVE

Most patients with uraemia must undergo chronic dialysis while awaiting kidney transplantation; however, the role of the pretransplant dialysis modality on the outcomes of kidney transplantation remains obscure. The objective of this study was to clarify the associations between the pretransplant dialysis modality, namely haemodialysis (HD) or peritoneal dialysis (PD), and the development of post-transplant de novo diseases, allograft failure and all-cause mortality for kidney-transplant recipients.

DESIGN

Retrospective nationwide cohort study.

SETTING

Data retrieved from the Taiwan National Health Insurance Research Database.

PARTICIPANTS

The National Health Insurance database was explored for patients who received kidney transplantation in Taiwan during 1998-2011 and underwent dialysis >90 days before transplantation.

OUTCOME MEASURES

The pretransplant characteristics, complications during kidney transplantation and post-transplant outcomes were statistically analysed and compared between the HD and PD groups. Cox regression analysis was used to evaluate the HR of the dialysis modality on graft failure and all-cause mortality. The primary outcomes were long-term post-transplant death-censored allograft failure and all-cause mortality started after 90 days of kidney transplantation until the end of follow-up. The secondary outcomes were events during kidney transplantation and post-transplant de novo diseases adjusted by propensity score in log-binomial model.

RESULTS

There were 1812 patients included in our cohort, among which 1209 (66.7%) and 603 (33.3%) recipients received pretransplant HD and PD, respectively. Recipients with chronic HD were generally older and male, had higher risks of developing post-transplant de novo ischaemic heart disease, tuberculosis and hepatitis C after adjustment. Pretransplant HD contributed to higher graft failure in the multivariate analysis (HR 1.38, p<0.05) after adjustment for the recipient age, sex, duration of dialysis and pretransplant diseases. There was no significant between-group difference in overall survival.

CONCLUSIONS

Pretransplant HD contributed to higher risks of death-censored allograft failure after kidney transplantation when compared with PD.

Mycobacterium tuberculosis after solid organ transplantation: A review of more than 2000 cases

BACKGROUND

Mycobacterium tuberculosis (TB) is a common pathogen worldwide, and it may cause significant infection after solid organ transplantation (SOT). We reviewed all reported TB cases to provide an update on its epidemiology, clinical presentation, management, and outcome after SOT.

METHODS

MEDLINE, EMBASE, and OVID were reviewed from January 1, 1998, to December 31, 2016, using keywords tuberculosis and solid organ transplant or transplantation.

RESULTS

There were 187 publications reporting 2082 cases of TB among kidney (n = 1719), liver (n = 253), heart (n = 77), lung (n = 25), and kidney-pancreas (n = 8) recipients. Among cohort studies, the median incidence was 2.37% (range, 0.05%-13.27%) overall. Most TB disease was considered reactivation of latent infection, occurring beyond the first year after SOT. Early-onset cases were seen among donor-derived TB cases. Fever was the most common symptom. Radiologic findings were highly variable. Extrapulmonary and disseminated TB occurred 29.84% and 15.96%, respectively. Multidrug-resistant TB was rare. Treatment using 4 or 5 drugs was commonly associated with hepatotoxicity and graft dysfunction. All-cause mortality was 18.84%.

CONCLUSIONS

This large review highlights the complexity of TB after SOT. Reactivation TB, donor-transmitted infection, extrapulmonary involvement, and disseminated disease are common occurrences. Treatment of TB is commonly associated with hepatotoxicity and graft dysfunction.

Heart Transplantation in Asia

Heart transplantation (HTx) is the effective way to improve quality of life as well as survival in terminal heart failure (HF) patients. Since the first heart transplant in 1968 in Japan and in earnest in 1987 at Taiwan, HTx has been continuously increasing in Asia. Although the current percentage of heart transplants from Asia comprises only 5.7% of cases in the International Society of Heart and Lung Transplantation (ISHLT) registry, the values were under-reported and soon will be greatly increased. HTx in Asia shows comparable with or even better results compared with ISHLT registry data. Several endemic infections, including type B hepatitis, tuberculosis, and cytomegalovirus, are unique aspects of HTx in Asia, and need special attention in transplant care. Although cardiac allograft vasculopathy (CAV) is considered as a leading cause of death after HTx globally, multiple observations suggest less prevalence and benign nature of CAV among Asian populations. Although there are many obstacles such as religion, social taboo or legal process, Asian countries will keep overcoming obstacles and broaden the field of HTx.

Factors influencing development and mortality of acute respiratory failure in hospitalized patient with active pulmonary tuberculosis: a 10-year retrospective review

BACKGROUND

Pulmonary tuberculosis with acute respiratory failure is fatal and is a burden in the intensive care units and leads to mortality. This retrospective study identifies the factors influencing the development of pulmonary tuberculosis requiring mechanical ventilation (TBMV) and mortality in the hospitalized patients with pulmonary tuberculosis.

METHODS

The medical records of hospitalized adult patients with pulmonary tuberculosis were retrospectively reviewed. Demographic data, clinical presentations, radiographic findings, biochemical tests, and clinical outcomes were collected. Data were compared by Student's t-test and Chi-square test between groups. Select variables that were statistically significant with P values <0.1 were introduced into a forward, stepwise, logistic regression model. Odds ratios (ORs) and their 95% confidence intervals (CIs) identified the independent influencing factors in the development of TBMV and mortality.

RESULTS

Of 268 enrolled patients, 185 (69.0%) were male. The patients were equally divided between the TBMV and non-TBMV groups. The shorter duration of illness (OR, 0.99; 95% CI, 0.98-0.99), underlying disease of AIDS (OR, 14.55; 95% CI, 1.71-123.91), presentation of fever (OR, 2.11; 95% CI, 1.20-3.71) and dyspnea (OR, 3.51; 95% CI, 2.02-6.11), large amount of acid fast bacilli on sputum smear (OR, 3.76; 95% CI, 1.90-7.47), lower serum albumin level (OR, 0.39; 95% CI, 0.26-0.59), and delayed initiation of anti-tuberculosis agents (OR, 1.06; 95% CI, 1.00-1.12) were independent factors to develop TBMV. Male gender (OR, 2.16; 95% CI, 1.01-4.61), consolidation pattern on chest X-ray (OR, 2.41; 95% CI, 1.17-4.98), and lower serum albumin (OR, 0.39; 95% CI, 0.21-0.71) were correlated to mortality.

CONCLUSIONS

The incidence and mortality rate of TBMV patients were high. Acute tuberculous pneumonia, underlying disease of AIDS, amount of acid fast bacilli, and delayed administration of anti-tuberculosis agents were independent risk factors to develop TBMV. Male gender, consolidation on chest X-ray, and low serum albumin were significantly related to mortality.