Subcutaneous fat necrosis causing neonatal hypercalcaemia

Abstract

Hypercalcaemia in neonates is rare and often asymptomatic, but can have significant morbidity. If severe, it can cause symptoms including irritability, vomiting and seizures. We present the case of a baby girl, born at term after a traumatic delivery, who developed severe hypercalcaemia with nephrocalcinosis. She had several large areas of subcutaneous fat necrosis following delivery, with prolonged low-level elevation of C reactive protein. Subcutaneous fat necrosis of the newborn is a rare and underdiagnosed condition, often accompanied by high plasma calcium. Although self-limiting, it is important to recognise and treat this condition to minimise kidney damage, and to avoid unnecessary investigations or treatment with long courses of antibiotics. The infant recovered well, although a degree of nephrocalcinosis remains.

Subcutaneous fat necrosis of the newborn – An atypical case with typical complications

“…The hypothesized cause of hypercalcemia is that granulomatous inflammatory cells in SCFN express high levels of 1‐alpha‐hydroxylase, the enzyme that converts 25‐OH vitamin D3 to its active form (1,25‐dihydroxyvitamin D3), which can stimulate intestinal calcium uptake 2,7‐9,12 . Hypercalcemia can also be explained by an increased bone resorption in SCFN due to higher prostaglandin E levels, 1,13 and by an increased calcium mobilization from resolving areas of subcutaneous fat necrosis 4 …”

Use of Zoledronic Acid in a Neonate with Subcutaneous Fat Necrosis Complicated with Severe, Refractory Hypercalcemia

“…5 Typically, hypercalcemic neonates are asymptomatic, but very high calcium levels (>12,8 mg/dL) can cause lethargy, irritability, hypotonia, constipation, vomiting, poor feeding, failure to thrive, and hypertension. 6 Hypercalcemia can significantly reduce urinary concentrating capacity, producing polyuria; renal failure and dehydration may also occur. Hypercalcemia may be fatal if unrecognized, with the development of seizures and ultimately cardiac arrest.…”

“…Hypercalcemia may be fatal if unrecognized, with the development of seizures and ultimately cardiac arrest. 3,6 In neonates, severe hypercalcemia occurs rarely and may be determined by iatrogenic vitamin D intoxication or excessive calcium supplementation, granulomatous disease, SCFN of the newborn, Williams' syndrome, and hyperparathyroidism.…”

“…Urine calcium, phosphate, and creatinine levels can help determine whether the kidneys are inappropriately retaining calcium, and a renal ultrasound should be performed if hypercalcemia is persistent and severe. 6 Infants with SCFN typically have low parathormone levels with elevated 1,25-hydroxyvitamin D levels, but 1,25hydroxyvitamin D levels may occasionally be normal. Granulomatous lesions, similar to sarcoidosis, can increase 1hydroxylase activity, with increased extrarenal production of 1,25-hydroxyvitamin D. Local inflammation may increase production of bone-resorbing prostaglandin E, which, in turn, may lead to osteoclast activation.…”

Subcutaneous Fat Necrosis of the Newborn: A Case Report of a Term Infant Presenting with Malaise and Fever at Age of 9 Weeks

“…The urinary calcium excretion rate was however not done to further confirm the presence of calcium in urine but the patient had normal kidney function. Elevated levels of serum calcium have been noted as a rare complication of SFN and usually occur with disease regression [ 15 , 16 ]. Symptoms of hypercalcemia include lethargy, vomiting, poor feeding with attendant weight loss, polyuria, and fever [ 17 ].…”