{'fraction_non_alphanumeric': 0.028739386022207707, 'fraction_numerical': 0.011757021554539516, 'mean_word_length': 5.055335968379446, 'pattern_counts': {'":': 0, '<': 2, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
PARTIAL ARYL SULFATASE A (ASA) DEFICIENCY IN METACHROMATIC LEUKIDYSTROPHY (MLD): A NEW VARIANT?

MLD is a degenerative neurologic disease associated with a deficiency of ASA. A nunber of variants have been described differing primarily in age at onset. ASA levels are decreased to <15% of nonnal, no ASA is demonstrable on electrophoresis, and sulfatide accumulates to varying degrees. We report here a patient with onset of seizures at 6 mos. who at 5 yrs. had spasticity and absent reflexes with normal nerve conduction velocity, spinal fluid protein and gail bladder function.WBC's and fibroblasts had 15% of normal ASA (MLD controls had 15% in WBC's and <5% in fibroblasts). Parents had 50% in both WBC's and fibroblasts, as did classic MLD heterozygotes. Electrophoresis revealed two bands of aryl sulfatase activity with decreased intensity of ASA. The pH optimum and Km of the mutant ASA in fibroblasts were similar to normal. S35 sulfatide accumulation in the fibroblasts was abnormal and comparable to MLD. After 20 passages, the patient's fibroblasts' ASA had increased to 30% of normal and sulfatide accumulation was normal. In contrast, neither MLD nor control cells showed changes in ASA or sulfatide accumulation.The clinical and laboratory observations suggest that this patient may represent a new variant of MLD and ASA deficiency. The partial deficiency of ASA, demonstrable on electrophoresis is similar to findings in Type III, GM2 gangliosidosis where residual hexosaminidase A behaves in a comparable fashion.