Cadmium Intoxication and Its Effects on Kidney Function / 대한신장학회잡지

ABSTRACT

Cadmium-containing compounds are widely used in the manufacturing of pigments, plastics, glass, metal alloys, and electrical equipment. Chronic low exposure of cadmium causes renal tubular dysfunction, emphysema, bronchial cancer, osteomalasia, multiple fracture or urethral stone. Occupations exposed to cadmium are increasing in industsralized country such as Korea, but there is a few systemic study on cadmium intoxication until nowadays. We studied the effects of cadmium on renal function, pulmonary function and bone mineral density in 5 workers exposed to cadmium. Cadmium in urine were increased [38.51+/-42.68 (7.27-101.07)mug/g creatinine(1 st exam), 0.70+/-7.16 (3.88-21.05)mug/g creatinine(2 nd exam)], respectively. Urine N-acetyl-beta-D-glucosaminidase(NAG) excretion rates[9.19+/-2.21(7.25-12.79) U/g creatinine] were increased, but urinary beta2-microglobulin(beta2- MG), urinary methalothionein(MT) excretion, 24 hour urinary protein, calcium excretions were not increased. Cadmium in urine was correlated with urine NAG(r=0.912, p=0.031) but no relationship with others. Glomerular filtration rate were all within normal limits. Complete blood counts, liver function, renal function, electrolytes were all within normal limits. In urinalysis and sediment examination, 4 cases showed no abnormalities, but 1 case showed proteinuria(30 mg/dL) and hematuria with dysmorphic RBC dominance(This case was diagnosed accompanying IgA nephropathy). In pathologic examination, all biopsy specimens showed mild interstitial fibrosis without inflammatory cell infiltration. Osteoporosis and obstructive lung defect were diagnosed in one case. We found urinary NAG excretion were increased and mild interstitial fibrosis at biopsy specimen were seen in all cases. It is necessary to follow-up for detection of proteinuria and decrement of GFR in each patients.