Severe Hypercalcemia due to Hypervitaminosis D in a Breastfed Infant.

Vitamin D is one of the most commonly recommended dietary supplements and is often the first medication ever prescribed in infancy. However, with the variety of concentrations available, including many over-the-counter formulations, dosing errors can easily occur. We present a case of a breastfed infant with a calcium level greater than 23 mg/dL (5.75 mmol/L), whose severe hypercalcemia was due to hypervitaminosis D from accidentally overdosed vitamin D supplementation. We consider the differential diagnosis for her presentation and review the interventions required for treatment of her hypercalcemia. Notably, we reinforce the importance of carefully reviewing dosing of vitamin D supplementation with families. We also discuss the management of hypercalcemia, including the role of fluids, diuretics, and glucocorticoids, as well as the long-term sequalae of severe hypercalcemia.

Primary Hyperparathyroidism From Ectopic Parathyroid Adenoma in a 12-Year-Old With Slipped Capital Femoral Epiphysis.

Primary hyperparathyroidism has been reported in pediatric patients presenting with slipped capital femoral epiphysis (SCFE), but never in patients with ectopic parathyroid adenoma. A 12-year-old boy with obesity and autism spectrum disorder presented with a limp and was found to have bilateral SCFE. Calcium was elevated to 12.3 mg/dL with parathyroid hormone (PTH) of 1191 pg/mL. Neck ultrasound revealed no parathyroid adenoma. He was discharged following bilateral surgical pinning with plans for outpatient workup. Repeat labs 5 days later demonstrated calcium had risen to 16.7 mg/dL. Technetium-99m sestamibi scintigraphy and a computed tomography scan revealed a 2.7 × 1.6 × 1.9 cm intrathymic mediastinal lesion. He underwent a thoracoscopic resection of the mass, and intraoperative PTH levels fell appropriately. Pathology revealed a parathyroid adenoma. Postoperatively, the patient developed hungry bone syndrome followed by normocalcemic secondary hyperparathyroidism which resolved with high-dose vitamin D supplementation. Primary hyperparathyroidism presenting as SCFE in a pediatric patient has been reported in 13 previous cases. This is the first reported case of bilateral SCFE arising from an ectopic parathyroid adenoma. Thoracoscopic resection is a relatively new approach in pediatrics. Primary hyperparathyroidism can be associated with SCFE, especially bilateral, and should be considered in patients with traditional risk factors for SCFE. Pediatric patients with primary hyperparathyroidism and negative neck imaging should be further evaluated for ectopic parathyroid adenomas with nuclear medicine or cross-sectional imaging that includes the head, neck, and mediastinum. Thoracoscopic resection can be considered in pediatric patients with mediastinal ectopic parathyroid adenoma.

Efficacy and Safety of High-dose Cholecalciferol in Patients With Inflammatory Bowel Disease Receiving Infliximab.

OBJECTIVE: Vitamin D deficiency is prevalent in patients with inflammatory bowel disease (IBD). The goal of this study was to assess the efficacy and safety of high-dose, interval cholecalciferol administration in patients with IBD receiving infliximab. METHODS: This prospective, longitudinal, open-label study enrolled pediatric and young adult patients with IBD and vitamin D deficiency. Subjects received 50,000 IU every 4 to 5 weeks (n = 11) or 100,000 IU every 6 to 8 weeks (n = 32) of oral cholecalciferol for 1 year. Dosing was directly observed and administered in conjunction with infliximab infusions. The primary endpoint was vitamin D sufficiency, defined as a 25-hydroxy-vitamin D (25-OHD) level ≥30 ng/mL. RESULTS: Forty-three participants constituted the primary analysis population. 25-OHD levels reached steady-state after the third dose, and mean increases in 25-OHD levels were 8 vs. 4.5 ng/mL in the 100,000 IU vs. 50,000 IU treatment groups, respectively. Only 43.8% of patients receiving 100,000 IU and 18.2% of patients receiving 50,000 IU achieved sufficiency. There was no difference in the 25-OHD level responsiveness in patients with Crohn disease versus those with ulcerative colitis (P = 0.72). There was no correlation between 25-OHD levels and clinical disease activity in patients with Crohn disease (P = 0.85) or ulcerative colitis (P = 0.24). CONCLUSIONS: Supplementation with cholecalciferol was well-tolerated and direct observation is a promising paradigm for ensuring compliance with therapy. Patients with IBD, however, appear to require high doses of cholecalciferol, with less than half of patients (37% overall) achieving vitamin D sufficiency. Additional studies are necessary to determine the optimal treatment regimens.

Long-Term Follow-up of Hypophosphatemic Bone Disease Associated With Elemental Formula Use: Sustained Correction of Bone Disease After Formula Change or Phosphate Supplementation.

In this article, we describe the long-term outcomes of children who were previously reported to have developed hypophosphatemic bone disease in association with elemental formula use. An extended chart review allowed for an updated report of 34 children with regard to severity/duration of bone disease, extent of recovery, and time to correction using radiology reports and biochemical data. After implementation of formula change and/or phosphate supplementation, we found that serum phosphorus concentration increased and serum alkaline phosphatase activity decreased in all patients, normalizing by 6.6 ± 4.0 (mean ± SD) months following diagnosis. The decrease in serum alkaline phosphatase from diagnosis to the time of correction was moderately correlated with the concurrent increase in serum phosphorus (R = 0.48, P < .05). Age at diagnosis significantly correlated with time to resolution (R = 0.51, P = .01). This study supports the earlier report that bone disease associated with hypophosphatemia during elemental formula use responds to formula change and/or phosphate supplementation.

Unexpected widespread hypophosphatemia and bone disease associated with elemental formula use in infants and children.

OBJECTIVE: Hypophosphatemia occurs with inadequate dietary intake, malabsorption, increased renal excretion, or shifts between intracellular and extracellular compartments. We noticed the common finding of amino-acid based elemental formula [EF] use in an unexpected number of cases of idiopathic hypophosphatemia occurring in infants and children evaluated for skeletal disease. We aimed to fully characterize the clinical profiles in these cases. METHODS: A retrospective chart review of children with unexplained hypophosphatemia was performed as cases accumulated from various centres in North America and Ireland. Data were analyzed to explore any relationships between feeding and biochemical or clinical features, effects of treatment, and to identify a potential mechanism. RESULTS: Fifty-one children were identified at 17 institutions with EF-associated hypophosphatemia. Most children had complex illnesses and had been solely fed Neocate® formula products for variable periods of time prior to presentation. Feeding methods varied. Hypophosphatemia was detected during evaluation of fractures or rickets. Increased alkaline phosphatase activity and appropriate renal conservation of phosphate were documented in nearly all cases. Skeletal radiographs demonstrated fractures, undermineralization, or rickets in 94% of the cases. Although the skeletal disease had often been attributed to underlying disease, most all improved with addition of supplemental phosphate or change to a different formula product. CONCLUSION: The observed biochemical profiles indicated a deficient dietary supply or severe malabsorption of phosphate, despite adequate formula composition. When transition to an alternate formula was possible, biochemical status improved shortly after introduction to the alternate formula, with eventual improvement of skeletal abnormalities. These observations strongly implicate that bioavailability of formula phosphorus may be impaired in certain clinical settings. The widespread nature of the findings lead us to strongly recommend careful monitoring of mineral metabolism in children fed EF. Transition to alternative formula use or implementation of phosphate supplementation should be performed cautiously with as severe hypocalcemia may develop.