Multi-Territorial Ischemic Stroke Following Russell's Viper Envenomation: A Case Report

Abstract

Snake envenomation is a major health concern in tropical countries. Russell's viper, one of the "big four" venomous snakes in India, is known for its hemotoxic venom that commonly causes coagulopathy, spontaneous bleeding, and local tissue damage. However, ischemic strokes following viper envenomation are rare and underreported. We describe a case of a 52-year-old healthy male who sustained Russell's viper bite, and he presented with profuse sweating, altered sensorium, and respiratory distress within hours of the bite and required mechanical ventilation and anti-snake venom (ASV) therapy. Despite timely ASV administration, the patient developed progressive neurological symptoms, including ptosis. MRI brain revealed multi-territorial acute infarcts involving the left parietal-temporal-occipital cortex, pons, and cerebellum. Stroke evaluation ruled out common etiologies, such as atherosclerosis, cardioembolism, and vasculitis. Coagulation studies revealed evidence of venom-induced consumption coagulopathy (VICC), suggesting that the procoagulant components of viper venom led to widespread thrombosis. With supportive care and antiplatelet therapy, the patient gradually improved and was discharged with residual aphasia, requiring rehabilitation. This case highlights an unusual but serious complication of Russell's viper envenomation, a multi-territorial acute ischemic stroke that was likely mediated by a venom-induced prothrombotic state. Clinicians should maintain a high index of suspicion for thrombotic events in patients with altered mental status following a viper bite, even in the absence of traditional stroke risk factors.

Keywords: ischemic cerebrovascular disease; multi-territorial infarct; ptosis; russell's viper; snake envenomation; venom-induced consumptive coagulopathy.

Figure 1. Non-contrast CT brain showing infarcts in the brain stem and cerebellum.

The CT image shows acute infarcts in the left brainstem (pons - yellow arrow) and left cerebellar peduncle (red arrow), as indicated by the hypodense areas marked by the arrows.

Figure 2. MRI brain showing multi-territorial infarcts in FLAIR sequence.

(A) Acute infarcts in the left brain stem (green arrow) and cerebellum (red arrow). (B) Acute infarcts in the left parietal, temporal, and occipital lobes (blue arrow). FLAIR: fluid-attenuated inversion recovery

Figure 3. Timeline of events during hospital stay.

ASV: anti-snake venom; FFP: fresh frozen plasma; WBCT: whole blood clotting time; GCS: Glasgow Coma Scale