Alkali treatment of renal osteodystrophy.

In 1960 a 5-year-old girl was found to have developed accelerated hypertension (B.P. 190/150) with blood urea 119 mg/ 100 ml. An intravenous pyelogram showed a small scarred left kidney (5-3 by 32 cm). There was also upper pole scarring with clubbed calyces on the right side. Left nephrectomy was performed and histological examination of the kidney confirmed pyelonephritic changes, and showed infiltration of the submucosa of the renal pelvis and ureter with inflammatory cells. Blood pressure fell for six months. It subsequently became raised, and was controlled by guanethidine 10-25 mg/day. Urine cultures were occasionally positive but long-term sulphadimidine controlled these episodes. From 1961 until 1970 the blood urea varied between 45 and 60 mg/100 ml In July 1969 she developed pain in the shins on walking, and was found to have a plasma alkaline phosphatase of 39 KA. units with calcium 9-2 and phosphate 3-3 mg/100 ml. X-ray pictures of both tibiae showed no evidence of bone disease. Her symptoms continued to trouble her, and she was admitted to hospital in April 1970 for further investigation. On examination she appeared fit with well-developed secondary sexual characteristics. Her height was 161 cm (50' percentile; unchanged for nine months before admission). Measurements of her segments were crown to pubis 76 cm, pubis to heel 85 cm, span 168 cm. There was no proximal muscle weakness, but her bones were tender, and both tibiae slightly bowed. Investigations were: plasma urea 55 mg/100 ml, sodium 135 mEq/l., potassium 3-2 mEq/l., chloride 110 mEq/l., CO2 18 mEq/1., calcium 9-0 mg/100 ml, phosphorus 2-7 mg/100 ml, alkaline phosphatase 52 K.A. units/100 ml, non-protein-bound hydroxyproline 3-7 mg/I. (normal < 2-9); creatinine clearance 41 ml/min (corrected for body surface area 1-73 m2); midstream specimen of urine was sterile; trace protein, glucose, amino-acids; 24-hour urine calcium 32 mg, phosphorus 720 mg. Urine acidification test showed minimum urine pH 6-5, maximum total acidity 38-0 ,uEq/min (normal >60), titrable acidity 6-1 g&Eq/min (normal >25), ammonium 31-9 uEq/min (normal >35). Arterial blood pH (before acid load) 7.24, base deficit 10 mEq/1. A bone x-ray film showed a typical "rugger-jersey" spine but no other abnormalities. The appearances of cancellous bone from the iliac crest biopsy specimen were typical of osteomalacia (maximum number osteoid lamellae 7, surface coverage 75%) and osteitis fibrosa (increase in number of resorptive areas, excess surface fibrosis, irregular cement lines). She was discharged without specific treatment. On her re-admission three months later she had more bone pain, and the creatinine clearance had fallen slightly to 29 ml/min. The defect in urinary acidification was still present and plasma alkaline phospha-