Diagnostic dilemma: Weakness in a man’s leg revealed his abnormally small brain

The patient: A 44-year-old man in France

The symptoms: For two weeks prior to going to the doctor, the man had been feeling mild weakness in his left leg. There weren’t any notable abnormalities in his medical history or neurological development, except for when a shunt had to be placed in his head when he was 6 months old. The shunt helped relieve fluid buildup in his brain, which had an unknown cause. When he turned 14 years old, the shunt was removed.