Hematoxylin-eosin–stained sections revealed discrete lobules of basophilic collagen bundles in both the superficial and the deeper reticular dermis. A von Kossa stain confirmed that the bluish material represented calcium encrusting the collagen fibers. The collagen fibers were generally intact, although some were necrotic and fragmented.
At follow-up on day 20 of life, all the lesions had enlarged. The largest lesion, which was on the right temple, measured 4.0 × 4.0 cm and showed a superficial ulceration covered with crust and draining chalky-yellow material. There was no surrounding erythema or edema. A skull radiograph showed cutaneous calcifications in a serpiginous pattern over the right parietofrontal region. There were no underlying bony abnormalities. The patient was treated with topical wound care for ulcerated lesions. All lesions resolved by 3.5 months of age.