Neuraminidase deficiency presenting as non-immune hydrops fetalis

A newborn infant with oedema, ascites and hepatosplenomegaly is described. In ascites fluid foamy macrophages were found, in a liver biopsy cytoplasmic inclusions and membrane-bound vacuoles were seen. Furthermore the child excreted excessive amounts of sialic acid-rich oligosaccharides in the urine, and therefore a neurovisceral degenerative disorder was assumed. The diagnosis of sialidosis was confirmed by enzymatic assay in cultured fibroblasts, in which a complete deficiency of the lysosomal enzyme neuraminidase could be demonstrated. After recurrent septicaemias the child became dystrophic and died at the age of 6 months. Our case is compared with sialidosis observed by other authors, …

Prenatal diagnosis of mucolipidosis II (I-cell disease)

A pregnancy at risk for mucolipidosis II (I-cell disease) was monitored in which an affected fetus was predicted on the basis of the analyses of lysosomal hydrolases in amniotic fluid and cultured amniotic fluid cells, and by the demonstration of an excessive accumulation of [35S] sulfate-labeled glycosaminoglycans in cultured amniotic cells. This diagnosis was confirmed by performing enzyme assays and [35S] sulfate incorporation studies on material derived from the aborted fetus.

The clinical spectrum of alpha-L-iduronidase deficiency.

We present five patients with alpha-L-iduronidase deficiency who do not have the typical Hurler or Scheie phenotypes; they are compared to 28 similarly atypical cases from the literature. Phenotypic differences are pointed out and intrafamilial similarities stressed. Among the various possible explanations for this situation, the existence of genetic compounds seems acceptable for some of the cases, but others seem to be caused by different mutations. The elucidation of these alternative possibilities from recent biochemical research is discussed.

Childhood neuromuscular disease with rimmed vacuoles

A 5-year-old boy suffered from a slowly progressive non-familial neuromuscular disease, clinically marked by generalised muscle weakness, atrophy and hypotonia, a "myopathic" EMG and mildly elevated CK values. His gastrocnemius muscle showed marked myopathy, type I fibre predominance, and numerous "rimmed" vacuoles. This boy's condition is regarded as a childhood neuromuscular disease with rimmed vacuoles.

CARDIAC PUNCTURE OF FETUS WITH HURLER'S DISEASE AVOIDING ABORTION OF UNAFFECTED CO-TWIN

Mucolipidosis I — A sialidosis

Mucolipidosis I is characterized by Hurler-like features and skeletal dysplasia with a cherry-red macular spot and signs of neurodegeneration involving neuronal cells and myelin. Excessive amounts of sialic acid-containing compounds were found in cultured fibroblasts, leukocytes, and urine of a patient with a clinical phenotype of mucolipidosis I. In cultured fibroblasts, profoundly diminished activity of an alpha-N-acetylneuraminidase (sialidase) was found. Mucolipidosis I thus appears to be a distinct disorder of complex carbohydrate catabolism caused by the genetic deficiency of a neuraminidase.

CHONDROITINSULPHATURIA WITH α-L-IDURONIDASE DEFICIENCY

Pränatale Diagnostik der Sialidose, eines Defektes des lysosomalen Enzyms Neuraminidase

Die Sialidose, eine lysosomale Speicherkrankheit aus der Gruppe der Oligosaccharidosen, ist ein genetischer Enzymdefekt mit stark eingeschrankter Lebenserwartung des betroffenen Kindes. Nach vorheriger Geburt eines an dieser Erkrankung verstorbenen Kindes gelang mit Hilfe der biochemischen Analyse von Amnionzellen der korrekte pranatale Ausschlus einer Sialidose unter Voraussage eines heterozygoten Ubertragerstatus. Aus nicht geklarter Ursache war das Wachstum sowohl der Amnionzellen als auch der postnatal untersuchten Fibroblasten deutlich vermindert. Diese Beobachtung sollte bei weiteren pranatalen Untersuchungen uberpruft werden. Die Moglichkeit der pranatalen Diagnostik einer Sialidose …

Mucolipidosis I: increased sialic acid content and deficiency of an alpha-N-acetylneuraminidase in cultured fibroblasts.

Abstract Extracts of fibroblasts derived from a patient with mucolipidosis I exhibited a fivefold increase in sialic acid content as compared to those of normal cells. About 80% of this sialic acid was linked to other molecules. Using neuraminlactose as a substrate, mucolipidosis I fibroblasts were found to be severely deficient in an “acid” α-N-acetylneuraminidase. Since other lysosomal hydrolase activities were normal, we hypothesize that the basic metabolic lesion in mucolipidosis I lies in a defective degradation of sialic acid-containing compounds due to the genetic deficiency of a neuraminidase.

N-Acetylneuraminic acid storage disease

Increased amounts of free sialic acid were found in body fluids, leukocytes, cultured fibroblasts, and liver tissue of a four-year-old boy with mental retardation, ataxia, and clinical and radiologic findings of a mild mucopolysaccharidosis. A diagnosis of Salla disease was made though in contrast to earlier reports, recurrent upper respiratory infections and hepatosplenomegaly were present already in infancy, and skeletal abnormalities of dysostosis multiplex were found in early childhood. Free sialic acid in the urine was identified as N-acetylneuraminic acid by 1H-NMR spectroscopy. Sialidase activities were normal. Increased amounts of bound sialic acid were found in liver and cultured f…