Tuberculosis of the colon in a kidney transplant patient

Tuberculosis as a cause of recurrent fever of unknown origin

Recurrent fever constitutes a diagnostic challenge for clinicians, due mainly to the intermittent nature of the fever that results in incomplete investigations. We describe three patients with recurrent fever thought to be due to tuberculosis, and review the 14 previously reported cases who fulfil the criteria of recurrent fever for at least 1 month's duration. The median duration of symptoms before diagnosis was 5 months, and the duration of the febrile bouts ranged from a few hours to 1 week. The most common complaints were constitutional symptoms and abdominal pain, and most patients had significant underlying conditions. The mortality rate was 31%, and was limited to the earlier cases. Routine laboratory studies are not very helpful for the diagnosis of this condition, and chest radiographs showed some alteration in half the cases at the time of diagnosis, although in some cases represented old, healed lesions. PPD testing was positive in most cases, particularly in those without underlying conditions. Empirical antituberculous therapy should be considered in cases of recurrent fever, especially in areas of high prevalence or in patients with predisposing conditions.

The use of cyclosporine modifies the clinical and histopathological presentation of tuberculosis after renal transplantation

Tuberculosis is one of the most frequent opportunistic infections after renal transplantation and occurred in 30 of 1264 patients transplanted between 1976 and 1996 at Hospital São Paulo - UNIFESP and Hospital Dom Silvério, Brazil. The incidence of 2.4% is five times higher than the Brazilian general population. The disease occurred between 50 days to 18 years after the transplant, and had an earlier and worse development in patients receiving azathioprine, prednisone and cyclosporine, with 35% presenting as a disseminated disease, while all patients receiving azathioprine and prednisone had exclusively pulmonary disease. Ninety percent of those patients had fever as the major initial clinical manifestation. Diagnosis was made by biopsy of the lesion (50%), positivity to M. tuberculosis in the sputum (30%) and spinal cerebral fluid analysis (7%). Duration of treatment ranged from 6 to 13 months and hepatotoxicity occurred in 3 patients. The patients who died had a significant greater number of rejection episodes and received higher doses of corticosteroid. In conclusion, the administration of cyclosporine changed the clinical and histopathological pattern of tuberculosis occurring after renal transplantation.

Mycobacterium tuberculosis infection in pediatric liver transplant recipients

OBJECTIVES

To study the incidence, clinical presentation, management, complications and outcome of tuberculosis in pediatric liver transplant recipients.

METHODS

A retrospective review of the medical records of children who underwent liver transplantation between 1991 and 1998.

RESULTS

Mycobacterium tuberculosis infection occurred in 6 of 254 (2.4%) children undergoing liver transplantation between 1991 and 1998. Cough, pyrexia and poor appetite were common presentations; one-half had normal chest radiographs. The median time to confirmation of diagnosis was 8 months (range, 1 to 17 months). Tests contributing to diagnosis included: Ziehl-Neelsen (ZN) stain (2 patients), M. tuberculosis polymerase chain reaction (1 patient), Mantoux test (1 patient) and histopathology (4 patients). Family health screening was productive for 4 patients. Duration of treatment varied from 9 to 18 months. Isoniazid-induced hepatitis was observed in 2 patients but resolved with dose reduction. Two patients died while receiving treatment, one of Klebsiella spp. septicemia and the other of pulmonary hemorrhage.

CONCLUSIONS

Tuberculosis after liver transplantation has a significant morbidity and mortality. Pretransplantation a personal and family history of tuberculosis must be sought, and screening of patients and their families should be considered. Standard regimens incorporating isoniazid and rifampin are effective, but regular monitoring of liver function is essential to detect drug-induced hepatotoxicity.

Tuberculosis in renal transplant patients

Tuberculosis (TB) was diagnosed in 25 of 466 patients who underwent renal transplant over a period of 15 years. TB developed from 1 month to 9 years post-transplant. In 56% of the cases the onset was within the first post-transplant year. TB affected several isolated or combined organs. Pulmonary involvement was present in 76% of cases, either as isolated pleuro-pulmonary (56%) or associated with other sites (20%). The non-pulmonary sites were: skin, joints, tests, urinary tract, central nervous system and lymphonodules. The diagnosis was confirmed by biopsy in 64% of the cases, by identification of tubercle bacilli in 24% and only at necropsy in 12% Biopsy specimens could be classified in three histological forms: exudative, that occurred in early onset and more severe cases granulomatous in late onset and benign cases; and mixed in intermediate cases. Azathioprine dosages were similar along post-transplant time periods in TB patients and in the control groups; and in TB patients who were cured and who died. The number of steroid treated rejection crises was greater in TB than in the control group. Prednisone doses were higher and the number of rejection crises was greater in TB patients who died than in those who were cured. Fifteen patients were cured and ten died, two of them of causes unrelated to TB. Six of the eight TB-related deaths occurred in the first 6 post-transplant months. The outcome was poor in patients in whom TB arose early in post-transplant period and where the exudative or mixed forms were present; whereas the prognosis was good in patients with late onset and granulomatous form of TB. In one patient TB was transmitted by the allograft.

Infection in renal transplant recipients. Current approaches to diagnosis, therapy, and prevention

Despite dramatic improvements in patient and renal allograft survival, infections continue to be an important cause of post-transplantation morbidity and mortality. Most serious infections manifest clinically as febrile diseases, and immunosuppression-induced compromised cell-mediated immunity is the basis for the predominance of infections due to opportunistic intracellular microorganisms. Diagnostic evaluation is guided by the timing of fever after transplantation, epidemiologic factors, and evidence of specific organ system involvement. Although current therapy of bacterial and parasitic infections is usually effective, the management of deep-seated fungal infections remains highly unsatisfactory. Cytomegalovirus disease, the single most important infection in some transplant centers, frequently presents as a self-limited viral syndrome; however, multiple organs may be affected. New measures for the rapid diagnosis and treatment of this viral infection hold promise. A number of recommendations have been proposed to prevent infections in renal transplant recipients; however, continued progress will depend primarily upon further refinements in immunosuppressive therapy.