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A neuropathologic study of three cases of prosaposin (pSap) deficiency (ages at death 27, 89 and 119 days), carried out in the standard autopsy tissues, revealed a neurolysosomal pathology different from that in the non-neuronal cells. Non-neuronal storage is represented by massive lysosomal accumulation of glycosphingolipids (glucosyl-, galactosyl-, lactosyl-, globotriaosylceramides, sulphatide, and ceramide). The lysosomes in the central and peripheral neurons were distended by pleomorphic non-lipid aggregates lacking specific staining and autofluorescence. Lipid storage was borderline in case 1, and at a low level in the other cases. Neurolysosomal storage was associated with massive ubiquitination, which was absent in the non-neuronal cells and which did not display any immunohistochemical aggresomal properties. Confocal microscopy and cross-correlation function analyses revealed a positive correlation between the ubiquitin signal and the late endosomal/lysosomal markers. We suppose that the neuropathology most probably reflects excessive influx of non-lipid material (either in bulk or as individual molecules) into the neurolysosomes. The cortical neurons appeared to be uniquely vulnerable to pSap deficiency. Whereas in case 1 they populated the cortex, in cases 2 and 3 they had been replaced by dense populations of both phagocytic microglia and astrocytes. We suggest that this massive neuronal loss reflects a cortical neuronal survival crisis precipitated by the lack of pSap. The results of our study may extend the knowledge of the neurotrophic function of pSap, which should be considered essential for the survival and maintenance of human cortical neurons.

Niemann-Pick disease type C (NPC) is a rare, neurovisceral lipid storage disorder caused by genetic defects in lipid transporting proteins. It is distinct from Niemann-Pick types A and B (sphingomyelin lipidoses) and displays genetic (mutations in the NPC1 or NPC2[=HE1] gene), biochemical, and clinical heterogeneity. Late infantile to juvenile forms of NPC predominate and are characterised by atypical behaviour, ataxia, dysarthria, dysphagia, dystonia, cataplexy, vertical gaze palsy, splenomegaly, and dementia. In adult variants, psychosis and dementia are common, and dysarthria, ataxia, splenomegaly, and vertical gaze palsy are further facultative signs. Routine laboratory results including serum cholesterol are normal. In bone marrow smears, sea-blue histiocytes are often demonstrated and foam cells sometimes seen. The diagnosis is confirmed by detecting free cholesterol accumulation in perinuclear granules (lysosomes) and reduced cholesterol esterification after challenge with exogenous low-density lipoprotein in fibroblasts. Alternatively or additionally, mutational analysis can be performed. Treatment is restricted to symptomatic measures, since there is no specific therapy.

Unlabelled: An infant with an unusual clinical presentation and course of Niemann-Pick disease type C (NPC) is described. The baby presented with severe pulmonary involvement and hepatosplenomegaly at the age of 3 months and died of respiratory failure at the age of 7 months. Cell hybridization studies revealed that the infant belonged to the rare genetic complementation group 2. To our knowledge, this is the third reported case with early-lethal pulmonary involvement in NPC. All three reported patients belong to the minor complementation group 2. An elder brother of the present case had also died at 6 weeks of age from NPC with severe pulmonary involvement. The two complementation groups cannot be distinguished from each other by clinical, cellular and biochemical criteria except for severe pulmonary involvement which may be characteristic of the second group., Conclusion: NPC may present in early infancy with severe pulmonary involvement mimicking interstitial pneumonia. Such manifestation may be characteristic of the rare genetic complementation group 2.

Unlabelled: The authors describe a case of disseminated lipogranulomatosis (Farber disease) presenting as nonimmune hydrops fetalis. This is the tenth lysosomal storage disease which can show this clinical manifestation. The literature is reviewed for all hydrops cases associated with lysosomal storage diseases., Conclusion: Although rare, the lysosomal storage diseases collectively are significant causes of nonimmune hydrops and appropriate investigations are required in all cases of unexplained hydrops fetalis.

Unlabelled: An earlier described patient with combined sphingolipidoses, Farber and Sandhoff disease, had two healthy older brothers and two further sibs, one with Sandhoff disease and one (a fetus) with Farber disease, showing segregation of the respective genes. The prenatal diagnosis in the latter was performed using lipid (sphingomyelin and glucosylceramide) loading tests on the cultured amniotic fluid cells. After 1-3 days of incubation the cells' lipid extract revealed radioactive ceramide to be released and highly accumulated. The deficiency in acid ceramidase was known from the patient with the combined diseases. Confirmation of the prenatal Farber diagnosis was done by similar loading tests on the fetal fibroblasts and by analysis of liver lipids of the less than 18-week-old fetus., Conclusion: This is the first report on the use of lipid loading tests on intact cultured cells for prenatal diagnosis of Farber disease. The postnatal diagnosis of Farber disease can also be readily made using those tests, as was shown in four further cases.

The bone marrow cytological storage phenomena in generalized lysosomal lipid storage disorders (Gaucher disease, Niemann-Pick disease, GM1-gangliosidosis, cholesterol ester storage diseases) are reviewed. The value of bone marrow cytology as a pre-screening method in the diagnostic strategy for the different diseases depends on the disease type suspected and the availability of biochemical screening methods. While cytological screening is not necessary in certain patients with typical clinical pictures, it may prove undispensable in others.

We found two patterns of leptomeningeal storage that reflect two basic visceral storage patterns in Fabry disease. (i) A generalized-type leptomeningeal storage pattern, affecting all main leptomeningeal cell types (external arachnoideal epithelium, fibroblasts, vessel wall elements), was a consistent finding in three cases of classical generalized visceral phenotype. (ii) A localized leptomeningeal storage pattern was expressed, to a high degree, solely in the external arachnoidal epithelium; this pattern was found in one case with the variant visceral-restricted-type storage (confined to the cardiocytes). Thus, the external arachnoidal epithelium may be particularly susceptible to Fabry lipid storage, probably caused by a distinctly larger sustained lysosomal lipid load as compared to other cell types.

Sphingolipid activator protein (SAP) deficiency, previously described in two sibs and shown to be caused by the absence of the common saposin precursor (prosaposin), was further characterized by biochemical lipid and enzyme studies and by ultrastructural analysis. The 20-week-old fetal sib had increased concentrations of neutral glycolipids, including mono-, di-, tri- and tetrahexosylceramide, in liver, kidney and cultured skin fibroblasts compared with the controls. Glucosylceramide and lactosylceramide were particularly elevated. The kidney of the affected fetus showed additional increases in the concentration of sulphatide, galactosylceramide and digalactosylceramide. Free ceramide was stored in the liver and kidney, and GM3 and GM2 gangliosides were elevated in the liver, but not the brain, of the fetus. Phospholipids, however, were normal in the affected fetus. In the liver biopsy of the propositus, who later died at 16 weeks of age, only a few lipids could be studied. Glucosylceramide, dihexosylceramide and ceramide were elevated in agreement with our previous study. Enzyme studies were undertaken using detergent-free liposomal substrate preparations and fibroblast extracts. The sibs' beta-glucocerebrosidase and beta-galactocerebrosidase activities were clearly reduced, but their sphingomyelinase activities were normal. The normal activity of the latter enzyme and the almost normal tissue concentration of sphingomyelin in prosaposin deficiency suggest that the prosaposin-derived SAPs are not required for sphingomyelinase activity in vivo. In keeping with the biochemical findings, skin biopsies from the sibs showed massive lysosomal storage with a vesicular and membranous ultrastructure. The function of SAPs in sphingolipid degradation and the role of SAPs for enzyme activity in vitro are discussed. In addition, the similarity in neutral glycolipid accumulations in Niemann-Pick disease type C and in prosaposin deficiency are noted. The phenotype of the prosaposin deficient sibs resembled acute neuronopathic (type 2) Gaucher disease more than Farber disease in several aspects, but their genotype was unique.

Very long chain fatty acids (VLCFA) were found to be markedly increased and phytanic acid was borderline above normal in formalin-fixed brain white matter of case with an unusual type of familial leukodystrophy with epitheloid cells as described previously by Gullotta et al. [Neuropädiatrie (1970) 2: 173-186]. Increased VLCFA in brain clearly demonstrate that the patient had suffered from a peroxisomal disease. This diagnosis is corroborated by ultrastructural findings in brain showing typical lamellar inclusions. The particular type of peroxisomal disorder present in case (heterozygote of X-linked adrenoleukodystrophy?) remains speculative.

Recently the intravenous enzyme replacement therapy with modified beta-glucocerebrosidase has become available for patients with M. Gaucher. We report here the considerable improvement of activity and vigor in a 5 year old girl with type 1 M. Gaucher administering 60 IU/kg every two weeks for 6 months. The platelet count increased from 82-96/nl to more than 150/nl and hemoglobin from 10.8 to more than 12 g/dl. Serum acid phosphatase decreased from 14.6 U/l to 5.9. U/l and angiotensin-converting enzyme from 327 to 102 U/l. The estimation of splenic volume by MRT showed a decrease by 40%, while liver size was not reduced within 6 months of therapy. MRT proved to be useful to demonstrate the bone marrow infiltration by Gaucher cells. The enzyme replacement therapy resulted in an objective response. No side effects have been observed so far. The extreme high treatment costs enforce a considerable dose reduction for maintenance therapy.

Cultured skin fibroblasts from controls and patients with lysosomal storage diseases were loaded with GM1 ganglioside that had been labelled with tritium in its ceramide moiety. After a 65-h or 240-h incubation, a large percentage of this ganglioside remained undegraded in GM1 gangliosidoses, whereas in the other storage diseases studied, one of its metabolites accumulated by 2-4 fold relative to controls. Labelled GM2 ganglioside accumulated in 4 variants of GM2 gangliosidosis, whereas labelled GM3 ganglioside accumulated in sialidosis, galactosialidoses and sphingolipid activator protein 1 (SAP-1, saposin B) and prosaposin (saposin A, B, C and D) deficient lipidoses. The reduced degradation of GM3 ganglioside in the SAP-1 and prosaposin deficiencies was attributed to the deficient function of SAP-1. The prosaposin deficient cells also showed a reduced re-utilization of radioactive metabolites from GM1 ganglioside (i.e. sphingosine and fatty acid) for phospholipid biosynthesis compared with fibroblasts from the SAP-1 deficient patient or normal controls. This anomaly was ascribed to the previously shown defect in ceramide degradation in prosaposin deficiency.

A 7-year-old boy had clinical features of metachromatic leucodystrophy (MLD), however, an increased urinary sulphatide excretion was found in the presence of normal arylsulphatase A (and alpha-galactosidase A) activity. A rectal biopsy showed metachromatically staining storage macrophages as well as nonmetachromatic, but PAS-positive, submucosal neurons filled with membranous cytoplasmic bodies. These two types of storage material led to testing for a sphingolipid activator protein (SAP) deficiency. Loading tests with sulphatide and globotriaosylceramide showed deficient turnover of both sphingolipids in cultured fibroblasts. Using the Ouchterlony method, there was no reactivity between a described anti-SAP 1 antiserum and the patient's fibroblast extracts. This new case of SAP-1 deficient MLD was compared with the four cases of this variant known from the literature. Our results indicate that rectal biopsy morphology and lipid loading biochemistry should prove useful for the screening of SAP defects.

Two female patients of German origin, aged 38 and 21 years, with myoclonus epilepsy and cerebellar ataxia, but without dysmorphic signs and dementia, were found to excrete normal amounts of sialyl oligosaccharides in their urine. The younger patient showed cherry red spots in her ocular fundi. The older patient had a brother with an autopsy-proven neuronal storage disease compatible with sialidosis, and in her rectal biopsy lamellar inclusion bodies were detected. Enzyme assays in cultured fibroblasts of both patients revealed a profound but incomplete deficiency of oligosaccharide sialidase activity and normal beta-galactosidase activity. Adult sialidosis was diagnosed in both patients. In their fibroblasts, moderate elevations of bound sialic acid could also be measured. The small residual sialidase activity, which in the older patient had a normal KM value, is considered responsible for the late onset and slow clinical course of the disease. It is concluded that in adult sialidosis the extraneural storage process can be difficult to demonstrate in terms of metabolite accumulation or excretion during the course of intraneuronal storage.

In two cases, after i.v. injections of colchicine serum concentrations of 170 ng/ml and 240 ng/ml were found before death. Colchicine was extracted from serum with the aid of Extrelut extraction columns and analysed using HPLC. Urine was also analysed and the findings were confirmed by drawing a UV-curve for colchicine using the stop-flow method. In one case, colchicine was still detectable in urine 10 days after injection.

In autopsied brain tissue from three cases with Leigh disease (subacute necrotizing encephalomyelitis, SNE) and controls, the activity of pyruvate dehydrogenase complex (PDHC) was determined under different conditions. It was found to be at the control level or increased, but not deficient. The activities of succinate dehydrogenase, fumarase, succinate cytochrome c reductase, cytochrome c oxidase, and glutamate dehydrogenase were measured as additional mitochondrial markers and showed no essential differences between SNE and control tissue. The metabolic defect in SNE remains unknown. According to the literature, the defect may be localized to the mitochondrial systems. However, the reported results indicate that it cannot be ascribed to PDHC function. Extensive biochemical studies are necessary for understanding of the pathogenesis in the fatal genetic metabolic disease.

We describe a patient who presented shortly after birth with hyperkinetic behaviour, myoclonia, respiratory insufficiency and hepatosplenomegaly. Gaucher-like storage cells were found in bone marrow. A liver biopsy showed massive lysosomal storage morphologically different to that in known lipid storage disorders. Biochemically, the patient had partial deficiencies of beta-galactocerebrosidase, beta-glucocerebrosidase and ceramidase in skin fibroblast extracts, but the sphingomyelinase activity was normal. Glucosyl ceramide and ceramide were elevated in liver tissue. Loading of cultured fibroblasts with radioactive sphingolipid precursors indicated a profound defect in ceramide catabolism. Immunological studies in fibroblasts showed a total absence of cross-reacting material to sphingolipid activator protein 2 (SAP-2). The patient died at 16 weeks of age. The fetus from his mother's next pregnancy was similarly affected. The possibility that the disorder results from a primary defect at the level of SAP-2 is discussed. We have named this unique disorder SAP deficiency.

Globoid cells leucodystrophy was diagnosed by specific enzyme assays in two siblings of one family. A male infant presented the typical symptoms of hyperirritability and progressive loss of psychomotor functions beginning at the age of 4 months. The progression of the disease lead to decerebration and death at 19 months of age. The elder sister had a normal development until her third year, when she developed exclusively symptoms of peripheral neuropathy. Up to the moment there are no symptoms of cortical function loss.

Niemann-Pick disease type B was diagnosed clinically and enzymatically in a 4 years old girl presenting with hepatosplenomegaly, diffuse interstitial infiltrations of both lungs on chest roentgenograms, and foam cells in the bone marrow aspirate. Intelligence and neurological examinations were normal. Spingomyelinase activity was almost totally deficient in leukocytes and cultured skin fibroblasts. Unexpectedly, fundoscopy revealed oculo-neural involvement with a reddish-brown spot of the macula comparable to but differing in some respects from the classic cherry-red spot found in neurolipidoses. By definition patients with type B Niemann-Pick disease should have no cerebral or oculo-neural involvement. Two comparable cases have been described in the literature. The prognosis of this special type is not yet known. For classification--and especially for genetic counselling--it seems important to include the possibility of oculo-neural involvement in the diagnosis of Niemann-Pick disease type B.

A 4 1/2 year old boy without previous neurologic disorders developed chronic hemorrhagic pancreatitis and was shown to have polyposis of the gallbladder. Neurologic symptoms emerged at the age of 5 years. The sonographic pattern of an echogenic gallbladder was suspect of metachromatic leukodystrophy. The definitive diagnosis was made by the findings of very low arylsulfatase A activity in the white blood cells and deposits of sulfatides in the stroma of the polyps of the gallbladder.

A case of globoid cell leukodystrophy (Krabbe's disease) was diagnosed prenatally by demonstrating a profound deficiency of cerebroside beta-galactosidase in cultured amniotic cells. The diagnosis was confirmed in the fetus aborted in the 19th week. In the cell-free amniotic fluid, normal enzyme activity was found. This finding, which had been demonstrated in a previous case, is discussed.

Total lactosyl ceramide beta-galactosidase (LC) activity from normal and pathologic human leukocytes and tissues was subdivided into LC I (EC 3.2.1.46) and LC II (EC 3.2.1.23) activity by means of specific inhibition of LC II with 5 mM p-nitrophenyl-beta-D-galactoside (Ki = 1.5 mM). In globoid-cell leudodystrophy, inhibition of total LC was nearly complete (only LC II is active), whereas in GM1-gangliosidosis Type 1, very little inhibition was found (only LC I is actict). Total LC activity was not significantly low in either of the diseases, which have different genetic origins. The ratio of LC I to LC II activity may display remarkable genetic variation in normal probands.

Pairs of cultured amniotic cells and maternal fibroblasts ("feto-maternal pairs") were studied for hexosaminidase A (HXA) and arylsulfatase A (ASA) activity. These lysosomal enzyme activities are genetically deficient in Tay-Sachs disease and metachromatic leukodystrophy, respectively. After HXA was standardized by relating it to hexosaminidase B (HXB) activity, a feto-maternal correlation coefficient of r = 0.51 (n = 32; 95% confidence limits 0.197-0.73) was found for the HXA/HXB activity quotients. This coefficient was near the 0.5 value theoretically valid for mother-child pairs, suggesting that the studied activities reflect essentially the genetic variability. The studies of ASA revealed a high variability of individual activities, which was reduced in two steps: (1) The ASA activity was related to the mean of two lysosomal reference enzyme activities, total hexosaminidase and acid beta-galactosidase. (2) Since the square root of ASA activity was found to follow more closely the variation of the reference activities, the square root of ASA activity over the mean reference activity was taken as a more standardized measure of ASA activity, and the quotient was treated statistically. Positive feto-maternal correlation of standardized ASA activity was obtained after the elimination of three pairs with extreme values. A correlation coefficient of 4 = 0.42 (n - 26; 95% confidence limits 0.039-0.695) resulted. The implications of these correlation studies for the problem of heterozygote identification by quantitative enzyme assays in families deficient in HXA and ASA activity were considered.

Sixteen pregnancies in families with children enzymatically diagnosed as having Krabbe disease (KD) were monitored for prenatal KD using the assay of galactosyl ceramide beta-galactosidase (GCG) in uncultured chorionic villi (CV), cultured CV, or cultured amniotic fluid cells (AFC). Prenatal KD diagnoses were made for 5 pregnancies on the basis of lower than 10% normal GCG activity in cultured CV or AFC. Uncultured CV were studied in 3 out of the 5 KD embryos, although the GCG activities of 14%-23% as compared with control villi were diagnostically inconclusive; the relatively high activities were considered to be caused by maternal GCG contamination of these very small villus samples. Although the villi from 6 of the other pregnancies yielded more conclusive results, the use of uncultured CV alone is not recommended for prenatal KD diagnosis, this material being subject to possible uncontrolled contamination with maternal enzyme.

Hexosaminidase (Hex) A, B, and C/S were electrophoretically separated from cultured amniotic fluid cells, fetal brain, and white blood cells. Photographs of cellulose acetate zymograms were evaluated by reflectometric scanning. The usefulness and limitations of this rapid method were shown. Hex A was completely absent in the amniotic fluid cells of one out of three pregnancies at risk for Tay-Sachs disease, but Hex C/S was present in this case. The prenatal diagnosis of Tay-Sachs disease was made, and confirmed with the fetal material after abortion. Hex C/S was distinguishable from a residual or "heterozygous" Hex A activity. In the two other risk pregnancies, reflectometric Hex A activities were found to be 50 and 34% of control; the heterozygous stage was presumed for the fetuses.

Galactosyl ceramide beta-galactosidase activity was determined in chorionic villi (CV) samples obtained between the 9th and 11th weeks of gestation from 5 women with pregnancies at risk for Krabbe's disease (globoid-cell leukodystrophy, KD). These enzyme activities were compared with those in controls, as well as with those in cultured amniotic fluid cells (AFC) from one of the five at-risk pregnancies and from 29 KD-risk pregnancies studied previously. The results of these CV enzyme analyses were such that one case of fetal KD was clearly diagnosable, one fetal genotype heterozygous for KD was presumed, and three normal fetal genotypes were suggested. The use of both uncultured and cultered CV can be recommended for prenatal KD testing, but AFC may continue to play an important role, too. Of the 58 prenatal KD tests we have evaluated since 1974, a positive diagnosis of Krabbe's disease was made (and confirmed after termination of pregnancy when feasible) in 23 which is significantly more than 25% of 58.

In a family with juvenile metachromatic leukodystrophy (sulfatide lipidosis) 2 patients showed residual arysulfatase A activities of 5--6%. The patients' healthy father was characterized biochemically by a 39% normal activity of leukocyte plus plasma arylsulfatase A. The father was further characterized by a high sulfatide excretion (0.2--0.5 mg/I urine) and, paradoxically, by a normal sulfatide degrading enzyme activity in vitro. This special carrier is suspected to be heterozygous for a) arylsulfatase A deficiency and b) arylsulfatase A (sulfatidase) lability. This presumed additional genetic defect could be the cause of the sulfatide excretion which, in turn, would be a sign of the preclinical stage of an exceptional form of adult metachromatic leukodystrophy. The normal sulfatidase activity seems to be due to an in vitro effect.

We describe a patient with the biochemically established combination of Farber and Sandhoff disease. A 6-month-old girl of consanguineous Turkish parents presented with hoarseness, stridor, scattered skin nodules, painful swelling of hand joints and ankles, and cherry-red macular spots. Until the age of 2 years her motor and physical condition deteriorated distinctly, however her mental state remained unchanged. A biopsied skin nodule disclosed lysosomal inclusions within storage cells that were typical of Farber disease (curved tubular structures). However, other inclusions (e.g. zebra bodies) were also found. Biochemical findings included ceramide accumulation in skin nodules and cultured fibroblasts, impaired ceramide degradation on loading of cultured fibroblasts with radioactive sphingomyelin, profoundly decreased ceramidase activity in fibroblasts as well as total beta-hexosaminidase activity in fibroblasts and serum, absent hexosaminidase A and B bands on cellogel zymograms, increased urinary oligosaccharide excretion of the Sandhoff disease type, and a partial reduction of ceramidase and total beta-hexosaminidase activities in fibroblasts from her father. A diagnosis of combined Farber and Sandhoff disease was made. The effect of both enzyme deficiencies on the clinical manifestations in this patient and the genetic basis of this combination require further studies.