Subcutaneous Fat Necrosis of the Newborn: An Uncommon Presentation With Typical Complications.

Subcutaneous fat necrosis of the newborn (SCFN) is an uncommon skin disorder seen in neonates, typically manifesting as subcutaneous nodules or plaques within the first few weeks after birth, often following a difficult delivery. The condition is associated with hypercalcaemia, which can present with symptoms such as lethargy, irritability, hypotonia and dehydration, sometimes resembling sepsis. Fine-needle aspiration cytology typically reveals adipocytes and needle-shaped crystals while showing little to no fat necrosis, inflammatory infiltrate or multinucleated giant cells. The diagnosis is confirmed by histopathology, which shows distinctive features of lobular panniculitis, mixed inflammatory cell infiltration and crystals arranged in a radial pattern. It is important to distinguish SCFN from other causes of lobular panniculitis, as early diagnosis and intervention are crucial to prevent potential long-term complications.