A Rare Case of Metachromatic Leukodystrophy Confirmed by Arylsulfatase A

Metachromatic leukodystrophy (MLD) is the rare neurometabolic disease caused by the deficiency of a lysosomal enzyme arylsulfatase A (ARSA) activity. The absence or deficiency of arylsulfatase a leads to accumulation of cerebroside sulfate within the myelinseath of the central nervous system (CNS) and the peripheral nervous system (PNS). This in turn causes the CNS and PNS to progressively deteriorate leading to both features of upper and lower motor neuron dysfunctions. Metachromatic leukodystrophy gets its name from the way cells with an accumulation of salfatides appear when viewed under a microscope. The salfatides form granules that are described as metachromatic which means they pick up colour differently than surrounding cellular material when stained for examination. The clinical features of brain dysfunction like gait disturbance, speech, hearing and visual problems appear gradually, become progressive and fatal over time. Our patient a 5 years and 6 months old developmentally normal boy presenting walking difficulty since his 2 years and 6 months which was gradually increasing. During this period he also developed speech difficulty, seizure followed by unconsciousness and severe respiratory distress for ten days. His investigations were suggestive of metachromatic leukodystrophy. There is no specific treatment to cure the disease. So proper counseling was done regarding the bad prognosis of the disease with symptomatic treatment.