Snakebite in north-eastern South Africa: Clinical characteristics and risks for severity

Objectives: To identify the toxicity profile of snakebites and to assess clinical severity. Methods: An analysis of all patients admitted to Ngwelezane Hospital’s Emergency Department with a diagnosis of snakebite over five years was done. All patients were admitted, assessed and standard haematological and biochemical tests were done. Patients were observed for a minimum of 12 hours’ observation. Results: In total, 879 cases were analysed. Envenomation was identified in over two-thirds of admissions. Cytotoxic snakebites accounted for 98% of envenomations. Only four cases of haemotoxic bleeding and five cases of neurotoxicity were admitted. Abnormal laboratory indices correlated with severity: INR > 1 5 (odds ratio 2.25, CI 1.12–4.53; p = 0.023), platelets < 100x109/L (OR 2.35, CI 1.01– 5.49; p = 0.048), haemoglobin concentration < 8.0 g/dL (OR 5.68, CI 2.15–15.00; p < 0.001) and leucocyte count > 10x109 (OR 3.15, CI 1.89– 5.26, p < 0.001). Children and delays to admission correlated to and were predictors of severity. Conclusion: Two-thirds of patients who present to hospital with snakebite will have symptoms of envenomation, with the overwhelming majority having been bitten by cytotoxic species. Some factors correlate to severity and may be useful for anticipating the patient’s clinical course.