[Gm1 gangliosidosis types 1 and 2 (author's transl)].

Two cases of gangliosidosis due to aggregates of Gm1 are described. The first patient was a female infant with noticeable retardation in psychomotor development, coarse facies, hepatomegaly, and X-rays showing skeletal anomalies in the large bones, vertebral column, cranium and ribs. She died at the age of 10 months of a septic condition. The second patient was a male infant; deterioration in psychomotor development was first noticed 8 months after birth and this progressed slowly to arrive at a vegetative state with convulsions and myoclonus. The child died at the age of 4 years. There were no signs of enlargement of visceral organs but a cherry red stain was observed in the ophthalmologic examination. In the first case, necropsy revealed the presence of a deposit substance in the histiocytes of the hepatic sinusoids, spleen, pancreas, thymus, septi and pulmonary alveoli, intestinal lamina propria, epithelial cells of the renal glomeruli, and in the neurons and glial cells of the brain. The same deposits were observed only in the neurons and glial cells in the second case. Ultrastructural examination showed the presence of typical cytoplasmic membranous bodies in the central nervous system of both patients. The beta-galactosidase activity in the urine of both patients during life was zero. There was a higher than normal total amount of gangliosides in brain tissue samples from both (1906.7 and 2459.9 NANA/g respectively) as compared with normal values (724.0). This increase was proportional to the rise in Gm1 ganglioside (76.8 and 89.6 percent molar respectively) as compared to control (27.0). These clinical, morphologic, and biochemical data characterize both types 1 and 2 of gangliosidosis due to Gm1 aggregates.