Mucopolysaccharidosis Ⅶ:report of a case and renew of the literature

objective To investigate the clinical characteristics and diagnosis of mucopolysaccharidosis Ⅶ. Method The clinical and biochemical features of an infant with mucopolysaccharidosis Ⅶ confirmed by enzyme assay were analyzed.Result The 2 month-old male infant showed hydrops fetalis，mental retardation，coarse face，corneal clouding，hepatosplenomegaly，hernias，Alder-Reilly granules in the leucocytes and decreased platelet(32×109/L).The biochemical markers showed urinary glycosaminoglycans(GAG)(532.8 mg/L，controls＜70.0 mg/L).The ratio of GAG/creatinine was 161.3(controls:26.2±11.7).Serum chitotriosidase activity was 315.8 nmol/(ml·h) [control ＜53 mol/(ml·h)].Beta-glucuronidase activity was deficient in isolated leukocytes.Conclusion Severe form of mucopolysaecharidosis Ⅶ exhibited characteristics of hydrops fetalis.hepatosplenomegaly， coarse face，thromboeytopenia and Alder-Reilly granules in the leucocytes.The measurements of GAG in urinary and beta glucuronidase in leucocytes are critical to diagnosis and deferential diagnosis.