Fucosidosis is one of a number of disorders called lysosomal storage diseases in which metabolic products accumulate in cells due to an enzyme defect. Defective enzymes are unable to breakdown certain molecules which are often toxic to cellular functions resulting in a variety of signs and symptoms.
This disorder results in multisystem disease but the most severe symptoms result from damage to brain cells. As a result, patients exhibit progressive deterioration of mental and motor functions. Infants with so-called type 1 disease have symptoms within the first year of life and may survive only a year or two. Type 2 disease has its onset usually in childhood but progresses more slowly and patients may live into the 4th or 5th decade of life. In each case, the disease is progressive and individuals gradually lose mental functions and become physically incapacitated. Bone cells are involved which can result in short stature, coarse facial features, and prominent eyes. Seizures have been reported. The liver and spleen are often enlarged but cells of the kidney and pancreas are involved as well. Some patients, especially those with the more severe infantile symptoms, have abnormal perspiration patterns with difficulty adapting to warm environments. Those with type 2 often develop dark red skin lesions consisting of enlarged blood vessels (angiokeratomas). Recurrent respiratory infections are common.
This is an autosomal recessive disorder that requires the presence of two mutations in affected individuals. The parents, who are clinically normal, carry only a single mutation. However, such parents have a 25% risk of having a child with fucosidosis from each pregnancy. The same mutations cause both type 1 and type 2 disease.
Pediatricians and neurologists usually make the diagnosis. No specific treatment is available for the primary disease but supportive treatment such as respiratory therapy can help many patients. Infections must be treated promptly.