Lipoid Proteinosis Due to Homozygous Deletion Mutation (c.735delTG) in the ECM1 Gene Presents with Seizures and Hoarseness but No Skin Involvement

Lipoid proteinosis (LP) is a rare autosomal recessive genodermatosis characterized by deposition of amorphous hyaline material in the skin, mucous membranes, and internal organs.1,2 The diagnosis is usually made by cutaneous manifestations, confirmed by characteristic histopathology depicting reduplication of the basal lamina.3 The characteristic clinical findings include generalized stiffening and scarring of the skin and mucosa and infiltration of the tongue, and the underlying frenulum limits the patients' ability to protrude their tongue. Infiltration of the vocal cords leads to characteristic hoarseness of voice, often the first diagnostic sign of the disease in early infancy or in the first year of life. Another characteristic sign is development of multiple beaded papules along the eyelid margins. The cutaneous findings are often associated with neurological signs and symptoms manifesting with epilepsy and neuropsychological abnormalities due to calcification of temporal lobes or hippocampi of the brain.4 LP is caused by mutations in the ECM1 gene on chromosome 1q21, encoding the extracellular matrix protein 1 (ECM1) which is present in four different isoforms due to alternative splicing. In this report we describe an Iranian LP patient with seizures and hoarseness, but with no evidence of skin involvement.