Cutaneous Osteomas in a Seven- Month-old Child

Cutaneous osteoma (CO) is a rare entity with only scattered cases reported in the literature. Cutaneous ossifications are divided into primary and secondary CO. Secondary CO accounts for 85% of cutaneous ossifications and develops within preexisting neoplastic or inflammatory skin lesions. Primary CO accounts for about 15% of cutaneous ossifications and develops on its own. A 7-month-old child, born as second trigeminus by cesarean section after IVF pregnancy, presented with incidental finding of multiple firm, nontender, subcutaneous pale-brownish papules scattered on the skin of the lower abdomen, arms and legs, measuring up to 7 mm. Changes were unremarkable in neonatal period. Changes became visible by the end of the fourth month of life. History specified no trauma, inflammatory changes, nevi, dermatologic or other significant medical conditions. Family history for CO or other associated diseases was negative. First punch biopsy (3 mm) obtained from the lower abdomen showed unremarkable epidermis but the dermis underneath showed well circumscribed spicules of mature lamellar bone entrapped mature adipose tissue without hematopoietic elements. Pathologist indicated CO. One month later, second 2-mm punch biopsy obtained from the left lower extremity confirmed CO indicated in first biopsy. Laboratory revealed elevated thyrotropin (TSH) up to 8.79 mIU/L (reference range: 0.4-4.0 mIU/L) and parathyroid hormone (PTH) up to 88 pg/mL (reference range: 15-65 pg/ mL). Other tests regarding thyroid hormone, calcium and phosphorous levels were unremarkable. Final pathology report of CO found in biopsies suggested three possibilities: Albright’s hereditary osteodystrophy (AHO), Gardner syndrome and progressive osseous heteroplasia. CO as primary form can occur de novo in the form of multiple miliary osteomas, widespread osteoma or plaque-like presenting as a single lesion, both found in neonatal period. All previously mentioned osteoma changes have a good prognosis. Unlike previously mentioned states with CO, AHOpsuedohypoparathyroidism type 1a has poor long term prognosis, where besides CO it manifests with obesity, developmental disability, short stature, round face and ganglia calcification. In our case, laboratory findings supported by histology suggested the AHO syndrome, although the phenotype-associated symptoms of disease were not present yet in infancy. Further follow up is needed. The initially mild cutaneous manifestations may herald a more progressive ossification disorder, as it could be associated with multiple endocrine hormone resistance enhanced with neurobehavioral and developmental problems. Treatment of the present underlying disease is the first step. If the patient is symptomatic, surgical excision including punch excisions is currently the treatment of choice for CO.