Osteoma cutis is a condition characterized by theformation of bone within the skin. Such aberrantossification of the skin and subcutaneous tissue isconsidered primary when it arises in the absence ofunderlying tissue damage or a preceding cutaneouslesion. Conversely, secondary osteoma cutis occurswhen skin ossification is the result of a pre-existingskin lesion, trauma, or inflammatory process [1,2].Although rare, primary osteoma cutis has beenassociated with a number of different geneticdisorders. Albright hereditary osteodystrophy (AHO),a condition first described in 1942 by Fuller Albright,is an autosomal dominant metabolic disorder causedby a mutation in the GNAS1 gene [3]. This disease isassociated with a variety of phenotypic traits includingcutaneous ossification, short stature, brachydactyly,obesity, and mental retardation. It should be notedthat brachydactyly is the most specific feature of AHO[4]. However, owing to variable expressivity individualsmay present only with a subset of these symptoms [5,6]. The cutaneous ossification observed in patientswith AHO may be seen in infancy or early childhoodand is sometimes the earliest presenting symptom.Nonetheless, because clinical features of AHO canbe seen in the absence of metabolic derangements(i.e. normal serum calcium, phosphorus, and PTHlevels) an early diagnosis is often missed and delayedfor many years. Herein, we present a case of miliaryosteoma cutis of the face in a 68 year-old woman withphenotypic features of AHO and laboratory studiesconsistent with type 1a PHP.
