Clinical symptoms observed after SE depend on the sting site, age, weight, and health of the victim. On the other hand, they depend also on scorpion species and the amount of injected venom. The first symptoms evolved from local signs (restlessness, sweating, vomiting, nausea, numbness, and inflammation) to shock (cardiovascular and respiratory disorders), in the absence of treatment. Classification of clinical manifestations based on the increased severity was proposed in 1998 at the meeting of Pasteur Institutes and Associated Institutes (ACIP). This classification was then revised by a group of experts; three classes based on observed signs and their amplitude have been identified. These signs may be local, moderate, or severe with no chronological order between them.
Most scorpion stings cause only localized signs and symptoms, such as pain and warmth at the site of the sting. Sometimes these symptoms may be quite intense, even if you don't see redness or swelling.
After SE, hemodynamic manifestations are the main causes leading to the death; scorpion venoms affect the cardiovascular system and may cause fatal pulmonary edema and cardiac arrhythmias. The main observed symptoms after envenomation are hypertension in mild cases and hypotension or acute pulmonary edema in severe cases. Marked increase in blood pressure associated with an acute left ventricular failure and elevation of pulmonary edema have been demonstrated by several studies. In severe cases of SE, pulmonary edema followed by respiratory disorders leads to death. Pathogenesis of pulmonary edema is dual; the mechanism of acute pulmonary edema has not yet been elucidated. Tissue damage is observed in almost all organs (including the heart, lungs, kidneys, liver, and spleen), but the most striking effect occurred in the lungs as a diffuse injury of the alveolar–capillary barrier, interstitial and alveolar edema associated with leukocytosis, epithelial transmigration, and marked fibrin deposits responsible for thrombi, wall infarct, and necrosis Tissue damage, respiratory distress syndrome, and multiple organ failure (MOF) could be related to the uncontrolled production of cytokines and other products after macrophage and lymphocyte activation.