Cherry red spots

Patients with sialidosis show a striking syndrome characterized by action myoclonus, cerebellar ataxia and a macular cherry red spot similar to that in Tay-Sachs disease but with preserved intellect. 

Tay-Sachs Hexosaminidase A Ganglioside GMj Cherry red spots in macula Blindness Psychomotor retardation Death usually <2 years... 

Cherry-red spot, Optic atrophy, Visual loss... 

Tay -Sachs disease (272800) causes cherry red spots in the. eye, startle" responses in infancy, neurodegeneration, and death. Heterozygotes with an abnormal Tay-Sachs allele are termed carriers. What is the risk that the grandmother of an affected child is a carrier ... 

The clinical picture is varied all types of motor, sensory, and mental deterioration may occur, with eventual complete collapse of the central nervous system. Cherry-red spots develop in the eyes of patients with Niemann-Pick disease just as in Tay-Sachs disease. 

CatA deficiency or mutations affecting the structural integrity of CatA, therefore, lead to accumulation of sialylated glycoconjugate substrates of Neu-1 and later to the severe genetic disease galactosialidosis [10]. Common clinical signs are massive edema, skeletal dysplasia, cherry red spots on the retina, and neurological deterioration. 

Eye Corneal opacities Lens opacities Cherry-red spot Optic atrophy Retinal degeneration + + + + +... 

Fig. 19.2. Clinical approach to the diagnosis of oligosaccharidoses and related lysosomal disorders with early (infantile) onset. Associated with CNS involvement of various types. Facial dysmorphism and/or skeletal (vertebral) involvement suggestive of dysostosis multiplex. Bold conditions associated with abnormal oligosacchariduria italics conditions associated with abnormal mucopolysacchariduria. The percentage of patients showing macular cherry-red spot (when present) is indicated in parentheses. Absence of visceromegaly...

The cherry-red spot in TSD results from changes of ganglion cells and nerve fibers of the retina comparable to those of the brain. There is swelling and necrosis of the ganglion cells in the macula, where they are particularly numerous, leading to a greyish-white appearance of this area, in the center of which the fovea appears dark-red due to the transparency of chorioideal vessels. Atrophy of the optic nerve with demyelination is secondary. 

Neurologic findings include cerebellar ataxia and extrap3rramidal rigidity which are not as common in TSD. A cherry-red spot is rarely seen, but retinitis pigmentosa as well as abnormal pupillary reactions are frequent. Cases without ophthalmologic abnormalities have been reported (Corberi 1926, Liebers 1927, Schneck et al. 1965b). 

Most publications on NVG contain incomplete lipid analyses or none. Craig et al. (1959) examined only some fractions of the liver lipids but not the brain. No chemical analyses were performed in the eight cases of Landing et al. (1964). In the case of Norman et al. (1959) with a cherry-red spot in the macula and hepatomegaly the spleen and liver hexosamine content was increased several-fold, while no neuraminic acid was present. Liver phospholipids but not total lipids were increased. 

A cherry-red spot in the retina has been seen by several authors. Data on its incidence vary from 20% (Crocker and Farber 1958) to over 50% (Videbaek 1949, and others). Baumann et al. (1936) found it in eight out of 27 patients and considered these cases to be a combination of NPD with Tay-Sachs disease. The sign results from the red color of the fovea being visible in the middle of a greyish-white macula it may appear at any time during the course of the disease and can occur unilaterally. Several authors (Wascowitz 1931, Rothstein and Welt 1941) differentiated these spots from those of amaurotic family idiocy on the basis of their color and shape. This is discussed in more detail by Goldstein and Wexler (1931) and by Rintelen (1935). 

The diagnosis of NPD has to be considered when hepatosplenomegaly develops in an infant in association with progressive neurologic symptoms. Additional clinical evidence for the disease is a cherry-red spot in the macula similar to that seen in Tay-Sachs disease, brownish-yellow skin pigmentation, cachexia, auditory and visual disturbances and developing idiocy. 

Goldstein, J., and D. Wexler Niemann-Pick s disease with cherry-red spots in macula, ocular pathology. Arch. Ophthal. 5, 704 (1931). 

Niemann-Piek disaase Isphingomyelin lipidesis) (Also see FATS AND OTHER LIPIOS.I taifficiBizt levels of the enzyme sphingomyelinase. Accumulation chiefly ol sphingomyelin and lecithin in the livei. spleen, and central nervous system, enlarged liver and sple mental and physical retardation cherry red spot on retina of eye. None of value. 

In a patient classified as mucolipidosis I, Ckmzetal (1977) and Spranger /. (1977) demonstrated a severe deficiency of an acid neuraminidase (sialidase N-acetyl neuraminic acid hydrolase, E.C. 3.2.1.18) in his cultured fibroblasts. The patient had a neurodegenerative disorder with myoclonus, skeletal changes like in Hurler disease, and cherry-red spots in the maculae of his eyes. In addition to the neuraminidase defect, the fibroblasts of the patient accumulated abnormal amounts of sialic acid-containing compounds. The patient excreted excessive quantities of sialyloligosaccharides in the urine (Michalski etal 1977). Fibroblasts from the parents of another such patient had activities of neuraminidase which were intermediate between patients and controls (Cantz and... 

Besides this group of dysmorphic patients there is another type of sialidosis with normal physical appearance, absent or mild mental retardation, and manifestation in adolescence. Durand etal. (1977), O Brien (1977), Thomas etal. (1978) and Rapin etal. (1978) showed that patients, who presented mainly with ophthalmological problems, or with the so-called cherry-red spot—myoclonus syndrome, had a profoundly diminished neuraminidase activity and excreted abnormal amounts of sialyloligosaccharides in their urine. 

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