ABSTRACT
A 60-year-old male patient on maintenance hemodialysis was started on antituberculosis therapy with isoniazid, rifampin, ethambutol, and pyrazinamide for pulmonary tuberculosis. After 4 weeks of therapy, he developed pruritic lesions in the extremities followed by exfoliation. The lesions progressively spread over the entire body. Lesions resolved after withdrawal of antituberculosis medications and administration of oral corticosteroids and antihistamines. After 2 weeks antituberculosis drugs were rechallenged one at a time. Administration of oral pyrazinamide resulted in reappearance of symptoms (pruritis and erythema) within 48 hours. Pyrazinamide was substituted with ofloxacin while other three drugs were restarted without any side effects. The case illustrates a rare but potentially dangerous complication of pyrazinamide therapy.
ABSTRACT
OBJECTIVES: Cystatin C is emerging as an endogenous marker of glomerular filtration rate. This study sought to assess the usefulness of serum cystatin C as a marker of glomerular filtration rate in comparison with serum creatinine and serum creatinine-based glomerular filtration rate estimations in voluntary kidney donors. MATERIALS AND METHODS: Serum cystatin C and serum creatinine were estimated in 35 voluntary kidney donors. Glomerular filtration rate was estimated using: (1) Cockcroft-Gault method normalized to 1.73 m(2) of body surface area, (2) 4-variable Modification of Diet in Renal Diseases formula, and (3) (99m)Tc-DTPA double plasma sampling method. Glomerular filtration rate-double plasma sampling method was used as a reference value. Results were expressed as means ± SD. RESULTS: The mean age of the participants was 44.23 ± 8.61 years old (19 women, 16 men). The mean serum creatinine was 0.83 ± 0.14 mg/dL, and the mean serum cystatin C was 0.71 ± 0.12 mg/L. Serum cystatin C showed significant correlation with serum creatinine (r = 0.864; P < .001). Glomerular filtration rate-MDRD showed the strongest correlation with glomerular filtration rate double plasma sampling method (r = 0.93; P < .001), followed by glomerular filtration rate-Cockcroft-Gault (r = 0.76; P < .001 ), serum creatinine (r = - 0.68; P < .001), and serum cystatin C (r = - 0.59; P < .001). The mean serum cystatin C values were 22.6% higher in men than in women. There was a significant correlation of serum cystatin C with glomerular filtration rate-Cockcroft-Gault (r = - 0.50; P = .002 ), glomerular filtration rate-MDRD (r = - 0.59; P < .001 ), and glomerular filtration rate-double plasma sampling method (r = - 0.59; P < .001 ). CONCLUSIONS: Serum cystatin C is an optimal marker of glomerular filtration rate in voluntary kidney donors.
