Three Siblings with Van der Knaap Disease

Megalencephalic leukoencephalopathy with subcortical cysts, also\udknown as van der Knaap disease, is a rare autosomal recessive\uddisease. The disease develops as a consequence of mutations in the\udgenes MLC1 and MLC2. A three years and nine months old male\udpatient was operated for right inguinal hernia. Physical examination\udrevealed macrocephalia, ataxia and mental retardation. Magnetic\udresonance imaging of the brain demonstrated megalencephalic\udleukoencephalopathy and subcortical cysts. These findings were\udconsistent with the diagnosis of van der Knaap disease. The patient\udwas born to consanguineous parents. Two siblings of the patient\ud(brother aged 23 years and sister aged 19 years), who showed\udsimilar neurological features, underwent genetic investigation\udand MLC1 gene mutation was detected. The presenceof this rare\uddisease was quite interesting. These cases point out that genetic\udcounseling is of importance in our country where consanguineous\udmarriage is common