Abstract 37: Adolescent primary hyperparathyroidism masquerading as rickets

Abstract

Introduction: Primary hyperparathyroidism (PHPT), is a rare disorder in pediatric age-group, with an estimated incidence of 2–5 cases in 100,000 live births. Around 80% children are symptomatic with renal or gastrointestinal manifestations. Presentation with skeletal symptoms is rare with less than 30 reported cases with most cases being misdiagnosed and treated as rickets.Case Synopsis: 14 year old boy presented with pain in both the legs and knock knees for 1 year. He was treated as nutritional rickets with oral calcium and vitamin D supplements for 1 month. He subsequently developed abdominal pain and recurrent vomiting. He was diagnosed to have abdominal tuberculosis and was started on empirical Anti- tubercular treatment. He continued to worsen symptomatically and was send to Endocrinology for evaluation of worsening leg deformity- ? Resistant RicketsOn examination his weight was <3rd centile, height 3-10th centile, waddling gait with genu valgum. Other systemic examination was normal.Investigations showed, corrected S. Calcium of 14.9 mg/dl, Phosphorus -2.9 mg/dl, ALP- 1277 IU/L, iPTH- 1900 pg/ml, 25(OH)D – 17 ng/dl, S. Creatinine -0.4 mg/dl and Hb-9.7 gm/dl. Ultrasound neck showed a 30 x19 x13 mm left parathyroid lesion with concordance in the Tc 99 Sestamibi scan. A clinical Exome sequencing for young onset PHPT was negative. He underwent a Left inferior parathyroidectomy and histopathology showed parathyroid adenoma. 4 months post-surgery, his S. calcium is 9.1 mg/dl on oral Calcium 500 mg twice a day. He gained 8 kilos and his bone pain and proximal myopathy has improved with persistent genu- valgum.