Back to METABOLIC DISORDERSThis condition is due to deficiency of glucosylceramidase, leading to a glucosylceramide lipidosis. There are infant, juvenile and adult forms. The infant form is characterized by early onset, marked hepatosplenomegaly and severe neurologic manifestations that result in early death. The juvenil form is similar to infant form, but neurologic manifestations are milder in the former.
The adult form, also called nonneuronopathic form, is the commonest lysosomal storage disease. The incidence is 30 times higher in ashkenazi jews ( 1 in 2500 births). Clinical manifestations include painless splenomegaly, which can lead to pancytopenia and bone pain of variable intensity. Patients may also present with pathological fractures, vertebral collapse and aseptic necrosis of femoral head. Diagnosis of bone disease may be done with MRI. Some degree, usually mild, of hepatic dysfuntion may occur, although severe hepatic failure, in rare cases, results in death. Characteristically, serum acid phosphatase is elevated. The disease is diagnosed by enzime assay, but the finding of a typical storage cell in bone marrow is almost diagnostic. This cell is also present in bone marrow of patients with granulocytic leukemia and multiple myeloma.
Treatment for the adult form includes partial or complete splenectomy, with posterior treatment of splenism. Bone marrow transplantation may be tried in life-threatening complications.
This condition reflects the accumulation of a trihexoside, galactosylgalactosylglucosylceramide, due to deficiency of a- galactosidase A. This disorder is X-linked and more common in men than women. Severe forms also occur in men and milder forms in women. Clinically, patients present with a painful neuropathy, mainly in the palms and soles, which can be intermittent or constant and shows a burning sensation. Painful abdominal crises may also occur, simulating an acute abdomen episode. Cutaneous manifestatons include angiokeratoma, characterized by angioectases that do not blanch with pressure, mainly in trunk, perineal area, penis and scrotum and hypohidrosis or anhidrosis, which can cause predispose to heat stroke with vigorous exercise. Occular findings, such corneal and lenticular opacities and tortuosity of retinal and conjunitival vessels are quite common. Cardiovascular manifestations result from lipid deposition on myocardium and are expressed by arrhytmias, acute myocardial infarction and orovalvular diseases. Small vessels involvement occur, predisposing patients to cerebral hemorrhages. Deposition of lipid in kidneys leads to progressive renal failure and this causes death in men at a median age of 41 years. Life expectancy is near normal in women.
Diagnosis is usually made through renal biopsy. Treatment includes counseling about the risks of anhidrosis, phenytoin for painful neuropathy and chronic dialysis for renal failure. Because donor´s kidney is not affected by the disease, renal transplantation is an acceptable alternative for the appropriate patient.
This disease results from sphingomyelinase deficiency, constituting a sphingomyelin lipidosis. In type A, the most common form, onset is after birth, with hepatosplenomegaly, failure to thrive and neurologic impairment. Retinal cherry-red spots appear, but seizures and hipersplenism are uncommon manifestations. Diagnosis may be given by finding distinctive Niemann-Pick cells in bone marrow, but is necessary to confirm it with specific enzime assay. In type B, a relatively benign disorder occurs, with hepatosplenomegaly and, sometimes, pulmonary infiltrates. There are not neurologic signs. In type C, progressive neurologic deterioration occurs in childhood. This form is not due to sphingomyelinase deficiency, but is associated to massive lysosomal accumulation of cholesterol, reflecting an intracellular defect of cholesterol utilization.
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