Neonatal subcutaneous fat necrosis with characteristic rash and hypercalcaemia

A 3.305 kg baby girl was born at term following an emergency caesarean section for reduced fetal movements and meconium staining of liquor. Cord blood gases showed pH of 7 and base deficit of 13.9. She fed poorly and developed symptoms of hypoglycaemia. Her lowest recorded temperature was 35.5°C. On day 4, she developed an extensive rash over her back, upper thighs and groin area. The rash was erythematous, indurated and tender on palpation, consistent with extensive subcutaneous fat necrosis (SCFN) (fig 1A). Investigations for sepsis revealed negative cultures.

Figure 1 Baby girl with subcutaneous fat necrosis at age (A) 5 days and (B) 9 months. Parental/guardian informed consent was obtained for publication of this figure.

When reviewed at 4 weeks of age the baby was failing to thrive and was hypercalcaemic with adjusted calcium level of 3.99 mmol/l. She received intravenous fluids, oral furosemide and spironolactone. She was given low calcium formula but her adjusted calcium level remained high at 4.0 mmol/l. A renal ultrasound showed medullary echogenicity consistent with nephrocalcinosis. She was given prednisolone (1 mg/kg/day) and diuretics were discontinued. The calcium level normalised and prednisolone was weaned over five weeks. At 9 months of age her weight remains below the 0.4th percentile. Serum calcium and creatinine are normal and the skin changes are less extensive, but areas of induration remain (fig 1B) and ultrasonographically nephrocalcinosis persists.

Subcutaneous fat necrosis is rare, but it requires careful investigation and follow up for potentially serious sequelae1,2 Treatment of hypercalcaemia is controversial.3