A Case of Late Infantile Metachromatic Leukodystrophy Presenting with Gradually-onset Paraplegia

Metachromatic leukodystrophy (MLD) is an autosomal recessive neurodegenerative disease, with an estimated prevalence rate of 1 per 40,000 to 160,000 worldwide. Progressive alteration in motor and cognitive functions is the most common clinical presentation. Late infantile MLD is the most common form of the disease that presents with a progressive decrease in visual acuity, impaired swallowing, muscle rigidity, seizures, and developmental delays. We herein present a rare case of late infantile MLD in a four-and-half-year-old male patient presenting with gradually-onset paraplegia.

 The patient had normal growth and neurodevelopmental pattern until 15 months of age. Afterward, he had a gradually increasing abnormality in gate and finally became paralyzed since the age of three years. The patient was also suffering from dysphagia, bilateral ptosis, and bad temperament. Normal metabolic test, myopathies, and brain MRI findings led to the diagnosis of MLD with gradually-onset paraplegia.

Generally, early diagnosis of MLD may increase the chance of recovery from the disease. We suggest considering MLD in patients suffering from behavioral, visual, and motor regressions, especially those with normal metabolic tests.