Hypoparathyroidism and pseudohypoparathyroidism: etiology, laboratory features and complications

ABSTRACT Objectives To identify a clinical profile and laboratory findings of a cohort of hypoparathyroidism patients and determine the prevalence and predictors for renal abnormalities. Materials and methods Data from medical records of five different visits were obtained, focusing on therapeutic doses of calcium and vitamin D, on laboratory tests and renal ultrasonography (USG). Results Fifty-five patients were identified, 42 females and 13 males; mean age of 44.5 and average time of the disease of 11.2 years. The most frequent etiology was post-surgical. Levels of serum calcium and creatinine increased between the first and last visits (p < 0.001 and p < 0.05, respectively); and serum levels of phosphate decreased during the same period (p < 0.001). Out of the 55 patients, 40 had USG, and 10 (25%) presented with kidney calcifications. There was no significant difference in the amount of calcium and vitamin D doses among patients with kidney calcifications and others. No correlation between serum and urinary levels of calcium and the presence of calcification was found. Urinary calcium excretion in 24h was significantly higher in patients with kidney calcification (3.3 mg/kg/d) than in those without calcification (1.8 mg/kg/d) (p < 0.05). Conclusions The reduction of hypocalcemia and hyperphosphatemia suggest an effectiveness of the treatment, and the increase in serum creatinine demonstrates an impairment of renal function during follow-up. Kidney calcifications were prevalent in this cohort, and higher urinary calcium excretion, even if still within the normal range, was associated with development of calcification. These findings suggest that lower rates of urinary calcium excretion should be aimed for in the management of hypoparathyroidism.

Nephrocalcinosis in neonates: report of 5 cases

The nephrocalcinosis is a pathologic entity rarely revealed to the neonatal period. The etiologies are dominated by hypercalciuria of prematurity whose origin is mostly iatrogenic. In full-term newborn, it refers primarily to the early revelation tubulopathy [distal tubular acidosis, Bartter syndrome] and primary hyperoxaluria, pathology common in the North African population. The prognosis depends on the extension of calcium deposits, the etiology and therapeutic options. In the pediatric nephrology department of the Charles Nicolle hopital, and during a period of 7 years from 2002 to 2008, we supported for nephrocalcinosis, 5 full-term newborns who fall into 3 boys and 2 girls. The average age of discovery is 19 days with extremes of 15 to 25 days. Consanguinity was present in 4 cases. The circumstances of discovery are: Acute dehydration with underweight in 2 patients. A urinary tract infection in one patient. NeonataI convulsions secondary to hypomagnesaemia. A chance discovery in the exploration of a symptomatology evocative of a gastrosophageal ref lux disease in a patient. Explorations turned up the diagnosis of distal tubular acidosis in 2 patients, a primary hyperoxaluria in 1 patient, idiopathic hypercalciuria in a patient and a family hypomagnesaemia with hypercalciuria and nephrocalcinosis in another patient