High ratio of 1,25-dihydroxyvitamin D3 to parathyroid hormone in serum of tuberculous patients with end-stage renal disease

• Published in: Clinical nephrology Vol. 62; no. 3; p. 202
• Main Authors: Yonemura, K, Ohtake, T, Matsushima, H, Fujigaki, Y, Hishida, A
• Format: Journal Article
• Language: English
• Published: Germany 01.09.2004
• Subjects: Aged; Aged, 80 and over; Biomarkers - blood; Calcitriol - blood; Calcium - blood; Female; Humans; Hypercalcemia - blood; Kidney Failure, Chronic - complications; Male; Parathyroid Hormone - blood; Tuberculosis - blood; Tuberculosis - diagnosis
• DOI: 10.5414/cnp62202
• ISSN: 0301-0430

Diagnosis of tuberculosis is sometimes difficult because of the low specificity of diagnostic procedures especially in patients on end-stage renal disease (ESRD). As abnormal vitamin D metabolism has been reported in tuberculosis, the aim of the present study was to determine whether serum concentration of 1,25-dihydroxyvitamin D3 (1,25-(OH)2D3) may be a useful diagnostic indicator of tuberculosis in patients with ESRD. Serum concentrations of 1,25-(OH)2D3, parathyroid hormone (PTH), and calcium were compared in 6 patients with ESRD and active tuberculosis (ESRD-TB group) and 110 patients with ESRD and no tuberculosis (ESRD group). These parameters were compared before and after treatment for tuberculosis in patients of ESRD-TB group. Hypercalcemia was observed in all 6 patients in the ESRD-TB group. Both higher serum concentration of 1,25-(OH)2D3 and lower serum concentration of PTH were observed in the ESRD-TB group relative to the ESRD group, suggesting enhanced extrarenal production of 1,25-(OH)2D3 and suppressed secretion of PTH by hypercalcemia in the ESRD-TB group. However, these parameters could not be used to distinguish the ESRD-TB group from the ESRD group. The ratio of 1,25-(OH)2D3 to PTH in serum was above 0.9 in the ESRD-TB group and below 0.9 in the ESRD group. Antituberculous treatment reduced this ratio to the range observed in the ESRD group. High ratio of 1,25-(OH)2D3 to PTH in serum is noted in active tuberculous patients with ESRD because of enhanced extrarenal production of 1,25-(OH)2D3.