GP262 Subcutaneous fat necrosis of the newborn: a case report and literature review

Introduction Subcutaneous fat necrosis of the newborn (SFNN) is an uncommon but important complication of perinatal care. While most cases resolve spontaneously, complications can include hypercalcaemia (up to 70%), thrombocytopaenia and hypertriglyceridaemia. We report a case of SFNN and a literature review of published cases. Case A term infant was treated with therapeutic hypothermia for grade 2–3 hypoxic ischaemic encephalopathy. On day 20 she was noted to have large plaques consistent with SFNN. At 4 weeks she developed hypercalcaemia requiring admission for intravenous fluids and furosemide. Her calcium normalised after 48 hours, and she commenced a low calcium diet. Parathyroid hormone and vitamin D were suppressed. She remains on low calcium formula at 7 months of age. Literature review Methods Pubmed was searched for English language articles using the keywords ‘fat necrosis’ AND ‘neonate or newborn’. 214 articles were screened, of these, 102 articles were included for review. Results Of 102 articles reviewed, 93% were case reports/case series, 4% were cohort studies and 3% were review articles. Comprehensive information was available for 119 individual case reports of SFNN. There was no gender predilection. Perinatal asphyxia or stress was reported in 78% (93/119). Delivery information was provided in 116/119 cases. Of these, 44% (51/116) were delivered by emergency caesarean section, and 11% (13/116) had an instrumental delivery. 21% (25/119) had hypoglycaemia. 20% (24/119) underwent therapeutic hypothermia. Median onset of skin lesions was day of life 6 (range: 1–70). Median duration of skin lesions was 62 days (range: 14–390). Hypercalcaemia developed in 53% (60/113). Median day of onset of hypercalcaemia was day 28 (range: 1–210). Median duration of hypercalcaemia was 26 days (range: 4–240). 52% (31/60) of hypercalcaemia was asymptomatic. Of those with hypercalcaemia, nephrocalcinosis was reported in 27% (16/60), subcutaneous calcification in 7% (4/60), and visceral calcinosis in 5% (3/60). Hypertriglyceridaemia was reported in 7% (8/119). Thrombocytopaenia was reported in 18% (21/119). Information regarding treatment was provided in 109/119 cases. 47% (51/109) were managed conservatively. Hyperhydration was required in 30% (33/109), dietary restriction of vitamin D/calcium in 27% (29/109), furosemide in 26% (28/109), glucocorticoids in 22% (24/109), bisphosphonates in 7.6%% (9/119), and calcitonin in 3.7% (4/109). Outcome information was provided in 106/119 cases. 87% (92/106) reported a full resolution. Persistent calcinosis was present in 5.7% (6/106). Conclusion Babies treated with therapeutic hypothermia should be closely monitored for SFNN, and development of hypercalcaemia.