PATHOLOGY RESEARCH AND PRAGICE © Gustav Fischer Verlag Lipoid Proteinosis of the Oral Mucosa: Case Report and Review of the Literature Kiriaki Aroni, Andreas Ch. Lazaris, Konstandina Papadimitriou, Helen Paraskevakou and Panayiotis S. Davaris Department of Pathology, Medical Faculty of Athens University, Greece Summary We describe a 37-year-old woman who presented with progressive mouth dryness. Physical examination re- vealed long-standing plaques on the face and upper limbs, papular lesions of the oral cavity and tongue firmness. A lower lip biopsy was performed. Light mi- croscopy demonstrated accumulation of PAS-positive material around blood vessels, capillaries and salivary gland canaliculi as well as focally massive hyaline de- posits in the submucosa. Immunohistochemistry re- vealed widespread presence of type IV collagen in the hyaline material and around thickened blood vessels. Laminin immunoreactivity was particularly strong at thickened basement membranes. The above findings were compatible with lipoid proteinosis, which is likely to involve primary perturbation of collagen metabolism and production of glycoproteins. Key words: Lipoid proteinosis - Oral mucosa - Histol- ogy - Differential diagnosis Introduction Lipoid proteinosis (LP) or hyalinosis cutis et mu- cosae is a rare genodermatosis characterized by de- posits of hyaline material predominantly involving the skin and mucous membranes of the mouth and upper respiratory tract. In the present article, we discuss this condition with particular reference to recent data con- cerning its clinicopathological features, pathogenesis and differential diagnosis. To the best of our knowl- edge, the present case is the first one officially reported in the Greek population. Pathol. Res. Pract. 194: 855-859 (1998) Concise Review of the Literature Since 1929, when LP was established as a distinct clinical and histological entity by the dermatologist Ur- bach and the otolaryngologist Wiethe, approximately 300 cases have been reported; however, LP is not as rare as it appears from the literature, for its clinical and histological findings can be easily misinterpreted. The disease affects both sexes equally; its incidence is increased in Sweden and South Africa, and the age of the patients at diagnosis ranges from 6 months to over 60 years. Although an autosomal recessive mode of in- heritance has been demonstrated in many cases of LP by parental consanguinity {l4], LP has been observed in two generations in some cases; therefore, heterozy- gotic LP manifestations are worth being investigated. LP is rarely reported to coexist with other genetic disor- ders (i.e. Ehlers-Danlos syndrome) [9]. LP mainly involves infiltration of the skin and mu- cous membranes. The patients' husky voice and thick- ened eyelids ("moniliform blepharosis") are particular- ly useful and early clues for the diagnosis of LP. Later, discrete or confluent yellowish, ivory or waxy nodules from pinhead to matchhead in size occur on the face, neck, axillae and hands in early life. Involvement of the scalp usually leads to loss of hair. Mucosal signs are present at birth or appear within the first few years of life. A gingival component of the LP entity has been confirmed [8]. Generally, the mouth is the most exten- sively affected area. Induration of the oral mucosa may also progressively begin in childhood [3]. Almost all Address for correspondence: Prof. Panayiotis S. Davaris, Dept. of Pathology, Medical Faculty of Athens University, 75 Mikras Assias str., Goudi, GR - 11527 Athens, Greece. Tel.: 00301-7771206, Fax: 00301-7781487, E-mail: a1azaris@cc.uoa.gr 0344-0338/98/0194-0855$5.00/0