Prevalence of mycobacterial infection in solid organ transplant recipients

Latent and active tuberculosis infection in allogeneic hematopoietic stem cell transplant recipients: a prospective cohort study

Tuberculosis (TB) is a major infectious complication in hematopoietic stem cell transplant (HSCT) recipients in countries with high TB prevalence. Identifying and treating latent tuberculosis infection (LTBI) helps to prevent TB reactivation after transplantation. Few studies have compared the tuberculin skin test (TST) with interferon Gamma release assays (IGRA) to diagnose LTBI in HSCT candidates. We compared TST and QuantiFeron TB gold in tube (QTF-GIT) and prospectively evaluated the incidence of active tuberculosis in 126 HSCT candidates and 58 HSCT recipients with chronic GVHD followed at the outpatient clinic. TB was diagnosed by culture in Mycobacteria media and by commercial real-time PCR kit. Considering the positivity of any test, the prevalence of LTBI was 8.7% in HSCT candidates (11 out of 126) and 12.5% in HSCT recipients with chronic GVHD (6 out of 48). QTF-GIT indeterminate results were detected in 2.4% of the HSCT candidates. Fair to good agreement (K > 0.50) between tests was observed in both cohorts. Cumulative incidence of TB was 3% in the GVHD cohort. TB was diagnosed in 2 chronic GVHD recipients, both cases confirmed by positive culture and PCR. None of the 11 patients with LTBI diagnosed pre-HSCT who received INH prophylaxis developed TB.

Infections in renal transplant patients: risk factors and infectious agents

AIM

Infectious complications after renal transplantation (RT) are associated with significant morbidity. They continue to be the most frequent cause of mortality. We investigated the incidence of infections, the causative pathogens, and risk factors contributing to this complication during the first year.

PATIENTS AND METHODS

We included demographic and clinical data of the 124 patients who underwent RT in our hospital from December 2004 to June 2010. for statistical analysis.

RESULTS

Fifty (40.3%) RT recipients developed 80 episodes of infection: urinary tract (n = 68; 85%), intraabdominal (n = 4; 5%), surgical wound (n = 3; 3.8%), or central venous catheter (n = 3; 4%). Eight (10%) were bacteremic. The most commonly isolated bacteria scene (76/80) was Escherichia coli (n = 43; 56.5%) followed by Klebsiella spp. (n = 10; 13.2%) and Pseudomonas spp. (n = 10; 13.2%). Cytomegalovirus infection was detected in 2 recipients; fungal and mycobacterial infections, in no case. It was noteworthy that 52.8% of E. coli and Klebsiella spp. produced extended-spectrum beta-lactamase. Ninety percent of infections developed within 6 months after transplantation. When we compared infected versus noninfected cases, the presence of a double J catheter was the most significant risk factor (P = .018; odds ratio [OR] = 0.234; 95% confidence interval [CI] = 0.070-0.781). In contrast to the initial years after the start of RT in our hospital the incidence of infection decreased over time together with a decrease number and durations of catheterization (P = .008; OR = 2.707; 95% CI = 1.292-5.672).

CONCLUSIONS

Urinary tract infections were the predominant problem with most isolates resistant to extended-spectrum antibiotics. Therefore, invasive catheters and prophylactic antibiotics should not be used for longer than necessary and infection control measures implemented to decrease the incidence of infections and bacterial resistance.

Renal tuberculosis in the modern era

Tuberculosis (TB) is a disease caused by Mycobacterium tuberculosis. The disease remains as an important public health problem in developing countries. Extrapulmonary TB became more common with the advent of infection with human immunodeficiency virus and by the increase in the number of organ transplantation, which also leads to immunosuppression of thousand of persons. Urogenital TB represents 27% of extrapulmonary cases. Renal involvement in TB can be part of a disseminated infection or a localized genitourinary disease. Renal involvement by TB infection is underdiagnosed in most health care centers. Most patients with renal TB have sterile pyuria, which can be accompanied by microscopic hematuria. The diagnosis of urinary tract TB is based on the finding of pyuria in the absence of common bacterial infection. The first choice drugs include isoniazide, rifampicin, pirazinamide, ethambutol, and streptomycin. Awareness of renal TB is urgently needed by physicians for suspecting this disease in patients with unexplained urinary tract abnormalities, mainly in those with any immunosuppression and those coming from TB-endemic areas.

Transplant-associated and blood transfusion-associated tropical and parasitic infections

Blood transfusion and transplantation may represent efficient mechanisms of spreading infectious agents to naive populations. In the developed countries, as a consequence of globalization, several factors such as international commerce, tourism, and immigration have acted as important features for the emergence or reemergence of infectious diseases previously referred to as tropical. This article reviews the relevant bacterial, protozoan and viral infections that are more frequently associated with blood transfusion and/or solid organ or marrow transplantation and may affect susceptible populations worldwide.

Tuberculosis in renal transplant recipients: the evidence for prophylaxis

BACKGROUND

Tuberculosis (TB) remains a leading cause of death in endemic countries and is 20 to 70 times more common in renal transplant recipients, where it contributes to both increased morbidity and mortality. This review will focus on the epidemiology of TB in renal transplant recipients and critically appraise the published literature on isoniazid prophylaxis in renal transplantation.

METHODS

A literature search for randomized and nonrandomized studies investigating the use of isoniazid prophylaxis in renal transplant recipients was conducted using Ovid MEDLINE, the Cochrane Library, the Transplant Library, and EMBASE. Relative risks (RRs) with 95% confidence intervals (CIs) are reported. Meta-analysis of the randomized controlled trials (RCTs) was performed with a fixed-effects model.

RESULTS

Eleven relevant studies were identified; six nonrandomized and five RCTs. The nonrandomized studies indicate a reduced risk of TB with isoniazid prophylaxis. The RCTs demonstrated conflicting results, with two studies finding a reduction in TB with prophylaxis and two studies finding no difference. Meta-analysis of the 709 patients from the four RCTs demonstrated a reduced risk of TB with isoniazid prophylaxis (RR, 0.31; 95% CI, 0.19-0.51). No significant difference was found in the incidence of hepatitis (RR, 1.22; 95% CI, 0.91-1.65).

CONCLUSION

Both randomized and nonrandomized studies support the value of isoniazid as TB prophylaxis in renal transplant recipients at risk of active infection. Clinicians should consider prophylaxis in renal transplant recipients in endemic areas or in recipients in nonendemic countries who are at risk. However, the evidence for the benefit of isoniazid prophylaxis in renal transplantation is not robust and there is still a need for a large multicenter trial of isoniazid prophylaxis in kidney transplantation in an endemic area.

Epidemiology of neglected tropical diseases in transplant recipients: review of the literature and experience of a Brazilian HSCT center

The rising success rate of solid organ (SOT) and haematopoietic stem cell transplantation (HSCT) and modern immunosuppression make transplants the first therapeutic option for many diseases affecting a considerable number of people worldwide. Consequently, developing countries have also grown their transplant programs and have started to face the impact of neglected tropical diseases (NTDs) in transplant recipients. We reviewed the literature data on the epidemiology of NTDs with greatest disease burden, which have affected transplant recipients in developing countries or may represent a threat to transplant recipients living in other regions. Tuberculosis, Leprosy, Chagas disease, Malaria, Leishmaniasis, Dengue, Yellow fever and Measles are the topics included in this review. In addition, we retrospectively revised the experience concerning the management of NTDs at the HSCT program of Amaral Carvalho Foundation, a public transplant program of the state of São Paulo, Brazil.

Kidney transplantation: Charles Nicolle Hospital experience

The aim of our retrospective study was to analyze the short- and long-term follow-up of 298 renal transplantations performed between June 1986 and May 2005. All were first transplantations except 4 cases, with 54 from cadaveric and 244 from living donors. The recipients included 196 males and 102 females of overall mean age of 31.21 +/- 8.9 years (range, 16-61 years). A combination of prednisolone and azathioprine was presented for 212 patients or mycophenolate mofetil for 86 patients. Polyclonal or monoclonal antibodies were used as induction therapy in 183 cases. Cyclosporine was administered to 188 cases and tacrolimus only to 16. HLA matching was 0 mismatches (MM) in 65 cases; 1 or 2 MM in 113; 3 MM in 99; and > or =4 MM in 21. Acute tubular necrosis occurred in 45 cases. One hundred eighteen patients experienced at least 1 acute rejection episode: 102 cases (41.8%) among living and 16 (29.6%) among cadaveric kidneys donor (P = .0007). The actuarial patient and graft survival rates at 1, 5, 10, 15, and 20 years were 95.9%, 87.4%, 77.5%, 65.6%, and 60.8%, and 94.9%, 84.5%, 75.4%, 65.4%, and 53%, respectively. Sixty-three patients died and 72 patients returned to dialysis. Our results were comparable to experienced centers. However, the member of kidney transplantations does not match the increased number of patients on renal replacement therapy. It is advisable to promote obtaining organs from brain-dead donors.

Infectious complications after kidney transplantation: a single-center experience

Infectious complications after renal transplantation are associated with significant morbidity and mortality. The prevalence of infections in transplant recipients varies from country to country. This study sought to assess the overall incidence of post-transplant infectious complications at our research center in Iran, compared with other centers in the world. Between 2002 and 2004, 179 renal transplantations were performed in our center. Of these, 142 were studied and followed for 1 year. Immunosuppressive regimens were cyclosporine, mycophenolate mofetil, and prednisolone. The overall incidence of infections was 54.2%. The most common sites of infections were the urinary tract (41.5%) and the respiratory tract (6.3%). The most frequent causes of infections were Klebsiella (24%) and cytomegalovirus (CMV) (17.6%). Wound infection occurred in 4.9% of the patients. Three (2.1%) patients developed hepatitis C and 2 (1.4%) had mycobacterial infections. There was no case of Pneumocystis pneumonia. Overall mortality was 7.7%. Infection-related mortality was 3.5%. In conclusion, this study identifies infections as the cause of morbidity and mortality in the post-transplant period. There was a low incidence of tuberculosis (<2% yearly) and a high incidence of CMV disease in our recipients.

Tuberculosis After Renal Transplantation

Tuberculosis (TB) remains a major public health problem in our country. Its diagnosis in immunodeficient patients is difficult. In this retrospective study, we analyzed the prevalence, clinical presentation, and outcome of TB after renal transplantation (RT) in our Tunisian team's experience. Among 359 renal transplant recipients, 9 (2.5%) developed TB at 49.6 months (range, 3-156 months) after RT. There were 7 men and 2 women of mean age 37.8 years (range, 15-53 years). The organs involved included lymph nodes in 1 case; lung in 5 cases; genitourinary system in 1 case; rachis in 1 case; pleural in 1 case; and both pulmonary and urinary systems in 1 case. The diagnosis was bacteriologic in 6 cases; histologic in 1 case; and 2 patients had a high index of suspicion. All patients were treated with a combination of rifampicin, isoniazide, pyrazinamide, and ethambutal. Recurrence of TB infection was noted in 3 cases with multiple localizations: lymph node, muscle abscess, meningitis, genitourinary system, rachis, and lung. Two patients died. In conclusion, among renal transplant patients, extrapulmonary involvement and recurrence of TB were frequent.

Mycobacterium tuberculosis infection following renal transplantation in Taiwan

BACKGROUND

Tuberculosis (TB) is one of the major causes of morbidity and mortality worldwide. Post-transplant (post-Tx) TB is a problem in successful long-term outcome of renal transplantation recipients. It is a life-threatening opportunistic infection that is frequently encountered, but the diagnosis is often delayed. With the emergence of newer potent immunosuppressive regimens and an increased incidence of TB in the general population, post-Tx TB among transplant recipients can be anticipated. Our objective was to describe the pattern and risk factors of TB infection, and the prognosis in an endemic area.

METHODS

This study was a retrospective review of the records of 756 renal transplant recipients in our hospital during the period from January 1983 to December 2003. The demographic data, transplant characteristics, clinical manifestations, diagnostic criteria, treatment protocol, and long-term outcome of this cohort of patients were analyzed.

RESULTS

Thirty-one episodes developed into TB in 29 patients (3.8%) with a mean age of 45.5 (range: 24.2-66.2) years and a mean post-Tx period of 57.9 (range: 1.2-145.2) months. The forms of the diseases were pulmonary in 22/31 (71%), disseminated in 1/31 (3%), miliary in 1/31 (3%), and extrapulmonary in 7/31 (23%). All patients initially received 4-drug combination therapy, and then dosage was adjusted based on clinical condition. Because of drug interaction, a mean 2-fold increase in the dose of calcineurium inhibitor, but no change in steroid, was required. Twenty-two patients (71%) had an elevated creatinine (Cr) level, and 6 (19%) patients did not recover owing to tissue-proof acute rejection (3 cases) and chronic allograft nephropathy (3 cases), respectively, after treatment. The serum Cr level on diagnosis of TB was 1.9+/-0.7 mg/dL; it then deteriorated to 2.4+/-1.5 mg/dL (P=0.134). Hepatotoxicity developed in 11 patients (35.5%) during treatment. Twenty-five patients were successfully treated, 2 patients remain under treatment, and 4 (12.9%) died. Based on univariate analysis, we found the post-Tx TB risk factors were diabetes and more than 3 episodes of rejection, modalities for acute rejection (high-dose steroid and anti-lymphocyte globulin), and maintenance therapy with steroid.

CONCLUSION

Post-Tx TB is a serious problem worldwide, and a high index of suspicion is warranted to ensure early diagnosis and prompt initiation of treatment for TB among renal transplant patients. The use of optimal immunosuppressive agents to minimize acute rejection seems reasonable to prevent TB infection in endemic areas like Taiwan. More than 9 months of treatment may be necessary to prevent recurrence.

[Vaccinations and solid-organ transplantation: review and recommendations]

Pediatric solid-organ transplant recipients are at high risk for various infectious diseases. Many children are not fully vaccinated before transplantation. To reduce the risk of morbidity and mortality from vaccine-preventable disease, physicians treating pediatric solid-organ transplant recipients should monitor the immunization status of these patients. Consensus on the most appropriate immunization schedule for solid-organ transplant recipients is lacking. Therefore, we provide a review of the currently available data on immunization safety and efficacy and describe strategies to avoid vaccine-preventable diseases in pediatric solid-organ transplant recipients.