Otological findings in idiopathic hyperphosphatasia

A 17-year-old male patient was admitted because of progressive hearing loss since the age of six. His former blood and radiology investigation had rev ealed idiopathic hyperphosphatasia. On ENT examination bilateral thickened tympanic membranes with severe mixed-type hearing loss was diagnosed. Compu terized tomography (CT) demonstrated expansion of the calvarial bones, incl uding the temporal bones, except for the otic capsule. Middle-ear explorati on revealed thickened middle-ear mucosa and a stone hard, immobile bony mas s instead of the normal ossicular chain at the posterior superior part of t he mesotympanum. No ossicular reconstruction could be attempted and the pat ient was rehabilitated with a hearing aid.