Radiolucent lesions of the maxillofacial complex in a patient with mucolipidosis type II (MLSII): case report

Mucolipidosis type II (MLSII) is a rare hereditary disorder of lysosomal storage. Affected individuals have severely impaired growth and rarely exceed 8 kg for body weight or 70 cm in height. Additional systemic features include; kyphoscolosis, umbilical and inguinal hernias, generalized hypotonia, and murmur of aortic insufficiency. Several oral manifestations have also been described, including gingival hyperplasia, macroglossia, impaired enamel formation, and delayed tooth eruption. Although the precise mechanisms responsible for the variety of clinical features is not fully understood, the underlying pathophysiology of MLSII is related to a lysosomal enzyme deficiency in which uridine diphospho-N-acetylglucosamine:N-acetylglucosylaminyl-1-phosphotransferase activity is impaired. This enzymatic deficiency, similar to other lysosomal enzyme deficiencies, leads to alteration in cellular architecture. There is abnormal vacuolization in cells of mesenchymal origin, especially fibroblasts, which leads to abnormalities in connective tissues. As a result, the skeletal system, cardiac valves, and renal glomerular podocytes are frequently involved. Unfortunately, complications related to cardiac and renal disease often severely compromise patient survival. Here we report the radiographic and histologic features of multiple radiolucent lesions associated with impacted teeth in a 12-year-old male with MLSII and review the relevant literature associated with this rare condition.