Lipoid proteinosis unveiled by oral mucosal lesions: a comprehensive analysis of 137 cases

Objectives: Lipoid proteinosis (LP) is a rare autosomal recessive disorder characterized by deposits of hyaline material within skin and mucous membranes of the upper aerodigestive tract, especially the vocal cords. We aimed to investigate possible associations between oral LP (oLP) manifestations and demographic data and extra-oral lesions. Material and methods: Cases of oLP were collected following a systematic search of Medline’s PubMed and Google Scholar (1948–2014). We added four new cases. Demographic data, consanguineous marriage status, oral lesion site(s), and related symptoms were analyzed for potential associations. Results: A total of 137 patients with oLP lesions were analyzed. Parental consanguinity status was known for 52 patients, and the parents were not related in 38 (73%) of them. The tongue was the most commonly affected oral site (68%), and it was associated with significantly more affected family members (P = 0.002). The palate and gingiva were the least involved sites (25 and 6%, respectively): the former had a tendency to be affected in younger patients and the latter in older ones. Patients with palatal and labial lesions had significantly less skin scarring (P < 0.001 and P = 0.002, respectively). Conclusions: Extra-oral manifestations are easily recognizable and they can lead to early and accurate diagnosis of LP. In spite of early voice manifestations, diagnosis of LP might be obvious only later in life and usually sought due to presence of oral lesions. Clinical relevance: The diagnosis of oLP with obscure extra-oral signs is challenging, with dental surgeons playing a key role in its establishment.