Subcutaneous Fat Necrosis

May 9, 2012

This lump on the back of a neonate was noted shortly after birth and had been expanding. What is it?

A 2-week-old neonate was brought to the emergency department for evaluation of a “lump” on the back. The lesion was first noted shortly after birth, but had been expanding since then. The delivery process had been long and complicated.

Key point: This history and lesional morphology are virtually pathognomonic for subcutaneous fat necrosis. Firm, erythematous nodules develop on cheeks, buttock, back, or thighs during the first 2 weeks of life, almost always following a stormy, often hypoxic delivery.

Treatment: The skin lesion need not be treated; it will resolve spontaneously.

Note: This rather banal appearing process may be complicated by life-threatening hypercalcemia. Serum calcium levels need monitoring and the neonate maintained in a well-hydrated state.