Accelerated brain infarction in hypertension complicated by hereditary heterozygous protein C deficiency.

Abstract
Protein C deficiency leads to reduced inhibition of coagulation and an increased likelihood of thrombosis. It is widely accepted that the most common syndromes associated with protein C deficiency are venous thrombosis and pulmonary thromboembolism, whereas arterial thrombosis is rare. Here we describe two patients with hypertension and hereditary heterozygous protein C deficiency who developed multiple lacunar infarcts. Patient 1 was a 46-year-old man with a history of hypertension who developed a right upper quadrantanopia and gradually progressive intellectual and behavioral deterioration. Patient 2 was a 61-year-old man with history of hypertension and two episodes of right-sided motor weakness who developed left sixth and seventh cranial-nerve palsies and reduced pinprick sensation in the right extremities. In both patients, magnetic resonance imaging revealed multiple small lesions in the pons as well as the bilateral basal ganglia, thalamus, corona radiata, and other subcortical structures, which are consistent with lacunar infarcts. Protein C activity and antigen levels were reduced to approximately one half of normal in these two patients, as well as in some of their family members who had no other serological or coagulation abnormalities. A diagnosis of heterozygous protein C deficiency type 1 was thus established. Although it remains uncertain whether protein C deficiency itself increases the risk of cerebral artery thrombosis, it may predispose a patient to develop multiple brain infarctions in association with hypertension.