Table 126-5.
LYSOSOMAL STORAGE DISEASES IN DOGS AND CATS
| Disease | Enzyme Defect | Breeds | Age of Onset | Clinical Signs | Diagnosis | Treatment |
|---|---|---|---|---|---|---|
| GM1 gangliosidosis | Beta-galactosidase deficiency | Portuguese water dog, English springer spaniel, Siamese cat, DSH | 2–4 months | Early cerebellar signs, UMN tetraparesis, dementia, seizures, cranial nerve deficits, visual deficits ± hepatomegaly, skeletal deformities, corneal opacities | Enzyme assays on WBC, plasma, other tissues; vacuolated WBCs | BMT with limited effect |
| GM2 gangliosidosis | Beta-hexosaminidase deficiency | Japanese spaniel, mixed-breed dog, DSH, Korat cat | 2–4 months (18 months in dogs) | Cerebellar signs, UMN tetraparesis, blindness, seizures, dementia ± skeletal deformities, corneal opacities | WBC, plasma, tissue assays; WBCs with heterochromatic granules | BMT with no clinical effect |
| Niemann-Pick disease type A | Sphingomyelinase deficiency | Balinese cat, Siamese cat, miniature poodle | 4–5 months | Cerebellar signs, LMN tetraparesis ± hepatomegaly | WBC, plasma, tissue assays | Not attempted |
| Niemann-Pick disease type C | Cholesterol transport defect | DSH, boxer | 2–4 months | Cerebellar signs, UMN tetraparesis, mentation changes ± hepatomegaly | Cholesterol esterification assays on cultured fibroblasts | BMT with limited effect |
| Mucopolysaccharidosis I | Alpha-L-iduronidase deficiency | DSH, Plott hound | 3–6 months | No neurologic signs, skeletal deformities, stunted growth, corneal changes | WBC, other tissue assays; urine screening test | BMT with moderate to marked effect |
| Mucopolysaccharidosis VI | Arylsulfatase B deficiency | DSH, Siamese cat, miniature pinscher | 2–6 months | See MPS-I; paraparesis due to cord compression | WBC, other tissue assays; urine screening test | BMT with moderate to marked effect |
| Alpha-mannosidosis | Alpha-mannosidase deficiency | DSH, DLH, Persian | 2–7 months | Cerebellar signs ± cataracts, hepatomegaly, limb deformities | WBC, other tissue assays | BMT with marked clinical effect |
| Fucosidosis | Alpha-fucosidase deficiency | English springer spaniel | 6–12 months | Behavior change, cerebellar signs, dementia, visual deficits, jaw chomping | WBC, plasma, CSF, or tissue assays | BMT with moderate effect |
| Neuronal ceroid lipofuscinosis | Defect unknown (mitochondrial subunit accumulates) | English setter, dalmation, border collie, Australian cattle dog, others | 1–2 years | Behavior change, dementia, visual seizures ± cerebellar signs | Brain biopsy or not attempted deficits, | BMT not effective in many breeds |
| Globoid cell leukodystrophy | Galactocerebrosidase deficiency | West Highland white terrier, Cairn terrier, miniature poodle, bluetick hound, beagle, others | 2–4 months | Cerebellar signs, paraparesis to tetraparesis | WBC, tissue assays; peripheral nerve biopsy | BMT not attempted in dogs (moderate success in mice) |
BMT, bone marrow transplantation (allogeneic); DLH, domestic longhaired cat; DSH, domestic shorthaired cat; MPS, mucopolysaccharidosis; LMN, lower motor neuron; UMN, upper motor neuron; WBC, white blood cell.