Multiple osteoblastomas in a child with Cushing syndrome due to bilateral adrenal micronodular hyperplasias

Adrenocorticotropin-independent adrenal hyperplasias are rare diseases, which are classified into macronodular (>1 cm) and micronodular (≤1 cm) hyperplasia. Micronodular adrenal hyperplasia is subdivided into primary pigmented adrenocortical disease and a limited or nonpigmented form 'micronodular adrenocortical disease (MAD)', although considerable morphological and genetic overlap is observed between the 2 groups. We present an unusual case of a 44-month-old girl who was diagnosed with Cushing syndrome due to MAD. She had presented with spotty pigmentation on her oral mucosa, lips and conjunctivae and was diagnosed with multiple bone tumors in her femur, pelvis and skull base at the age of 8 years. Her bone tumor biopsies were compatible with osteoblastoma. This case highlights the importance of verifying the clinicopathologic correlation in Cushing syndrome and careful follow-up and screening for associated diseases.