Biochemical vitamin B6 deficiency in adults with chronic glomerulonephritides with and without the nephrotic syndrome.

Thirty four patients suffering from chronic glomerulonephritides with and without the nephrotic syndrome and with an average age of 35 years were studied. Twenty eight of the patients underwent renal biopsy, as part of their management, and the histological classification was as follows: 7 membranous glomerulonephritis, 3 proliferative glomerulonephritis, 11 mesangiocapillary glomerulonephritis, 2 minimal change disease, 2 mesangial proliferative and 3 diffuse proliferative glomerulonephritis. Fourteen of the patients were on therapeutic diets mainly high protein - low salt and low cholesterol. Eighty three per cent of these patients were found to be biochemically deficient in vitamin B6 as judged by plasma pyridoxal-5-phosphate levels. No correlations were found between vitamin B6 and serum albumin, histological type of renal disease, duration of illness or serum cholesterol. By contrast, none of the patients with histologically similar disease that were daily receiving 25mg pyridoxine orally at the time of study were deficient. The importance of vitamin B6 deficiency in the nephrotic syndrome is discussed and it would appear that supplementary vitamin B6 should form part of the overall management of these patients.