Tuberculosis in active dialysis patients in Jeddah.

The incidence of tuberculosis in The Kingdom of Saudi Arabia remains high. The objective of this study is to determine the prevalence of Tuberculosis among haemodialysis patients, since they are highly susceptible to this infection. A retrospective study, over a 5-year period, was carried out in the Renal Units of two large hospitals in Jeddah. Diagnosis was established by Ziehl Neelsen microscopy and culture of specimens on Lowenstein-Jensen media, radiological and histological examinations. Tuberculosis was diagnosed in 17 of 210 patients on hemodialysis. Pulmonary tuberculosis was present in 10 cases and tuberculous lymphadenitis in 8 cases. One patient had both pulmonary and lymph node involvement while another one had both pulmonary and peritoneal tuberculosis. Mycobacterium tuberculosis was diagnosed in sputum in 5 cases, by lymph node histopathology in 5 cases, and combined radiological and clinical evidence in the remaining patients. The Mantoux test was positive in 9 (60%) cases. Eight patients were diabetics (47%) and there appears to be some association of tuberculosis with diabetes in patients on dialysis. Treatment with first-line anti-tuberculosis agents was continued for 6-18 months. Fourteen (82%) patients were completely cured while 3 showed clinical improvement only. The study showed that successful therapy of tuberculosis in this group of dialysis patients could be achieved but high index of suspicion is required to recognize the unusual presentation in this group of patients so that early diagnosis can be achieved and prompt treatment instituted. Diabetic patients presenting for dialysis, in areas with high endemicity for tuberculosis, chemoprophylaxis with anti-tuberculosis agents should be considered.

Cyclosporine-induced elevation in circulating endothelin-1 in patients with solid-organ transplants.

The long-term use of cyclosporine is associated with significant complications, including hypertension and renal failure. Recent data from animal experiments suggest that alterations in renal function induced by high-dose CsA may be mediated by endothelin-1 (ET-1), a potent endothelium-derived vasoconstrictor and mitogenic peptide. The aim of the present study was to determine the effect of oral CsA on circulating levels of ET-1 in patients receiving standard immunosuppressive therapy following solid-organ transplantation (13 renal, 7 heart, 1 heart-lung, 1 liver). Plasma levels of ET-1 were measured by radioimmunoassay over a 24-hr period beginning with the oral administration of a single daily dose of CsA in 18 patients (5.6 +/- 0.5 mg/kg), or similar immunosuppressive therapy without CsA in 4 patients. Blood levels of CsA (parent compound and metabolites) were measured in 10 of the patients by RIA. Predose levels of ET-1 were similar in the two groups (1.73 +/- 0.32 and 1.29 +/- 0.9 pg/ml, respectively). Patients not receiving CsA showed no change in plasma ET-1 over the 24-hr period. In contrast, in the CsA-treated group there was a significant increase in plasma ET-1, reaching a peak at 6 hr (2.45 +/- 0.56 pg/ml, P < 0.03) that followed the peak increase in CsA parent compound and preceded the peak increase in metabolites. No significant differences were found between peak and trough levels of ET-1 in patients with moderate renal dysfunction (creatinine (Cr) > or = 150 mumol/L) compared with those with near-normal renal function, or patients receiving renal compared with nonrenal grafts. However, patients with long-term grafts (> 60 days) showed an exaggerated response to CsA, with a fractional increase in plasma ET-1 of 3.67 +/- 0.52 (n = 8) compared with 2.16 +/- 0.28 (n = 10) for patients with more recent grafts (P < 0.05). Therefore, oral administration of CsA causes an increase in circulating ET-1 in patients with solid-organ transplants that might contribute to CsA-associated nephrotoxicity and hypertension, particularly during long-term immunosuppressive therapy.