Diferrante Syndrome

At a glance

This is a medical condition that belongs to a larger group of disorders classified under mucopolysaccharidosis. Diferrante Syndrome has been associated with a questionable glucosamine-6-sulfate sulfatase deficiency. Scientific fraud in Diferrante’s laboratory has been highly suspected (see “History”). Therefore, this syndrome has been retained here only for historical reasons.

Synonyms

Glucose-6-Sulfate Sulfatase Deficiency; Mucopolysaccharidosis Type VIII.

History

This medical condition was first described in Science by N. Diferrante in 1978. The scientific community raised considerable concerns about potential methodological fraud in Diferrante’s laboratory when the phenotype was later demonstrated to be the results of incorrect data. Only one patient was ever reported from this lab! Therefore, this syndrome has been retained here only for historical reasons.

Incidence

Only one patient has been described.

Genetic inheritance

Autosomal recessive.

Pathophysiology

Mucopolysaccharidoses represent a group of hereditary disorders involving lysosomal enzymatic defects affecting the degradation of mucopolysaccharides present in connective tissue. Nearly every organ of the body shows an accumulation of incompletely metabolized mucopolysaccharides.

Diagnosis

The patient excreted keratan and heparan sulfate in the urine. Lymphocytes stained with toluidine blue show a peculiar ring-shaped metachromasia underlying the cell membrane.

Clinical aspects

The syndrome combines clinical and biochemical features of the Morquio and Sanfilippo Syndromes. The affected patient had a short stature with mild dysostosis multiplex and hypoplasia of the odontoid. He was mentally retarded and presented with hepatomegaly and hirsutism. He had no ocular involvement.

Precautions before anesthesia

Obtain radiographs of the cervical spine to document atlantoaxial instability. Pulmonary function testing should be obtained in view of a probable Restrictive Pulmonary Syndrome in relation with the short stature. Baseline liver function should be obtained.

Anesthetic considerations

Difficult tracheal intubation is the rule and fiberoptic intubation should be considered. In spite of the atlantoaxial instability, mucopolysaccharides may accumulate in the tongue and nasopharyngeal tissues, making visualization of the glottic opening difficult during direct laryngoscopy. Hence, patients may also present with obstructive apnea and increased sensitivity to the ventilatory depressant effect of narcotics, so regional anesthesia for postoperative pain control is recommended, as well as observation in the intensive care unit for 24 to 48 hours. Finally, the heart may be affected by mucopolysaccharide accumulation in different ways, so the dose of anesthetics should be adjusted accordingly.

Pharmacological implications

If liver function is decreased, then certain medications, such as muscle relaxants, should be given in a reduced dose.

References