scorpion sting is an acute life - threatening , time - limiting , medical emergency of villagers and is a neglected public health problem in tropical and sub - tropical countries , especially in india . mesobuthustamulus , an indian red scorpion , is the most lethal species of the buthidae family in india . most of the stings are harmless and follow a benign clinical course , but morbidity and mortality due to scorpion stings result from acute refractory pulmonary edema , cardiogenic shock and multi - organ failure . previously , many drugs were used in the treatment of scorpion sting but , following the advent of the alpha-1 blocker prazosin , the fatality rate has been reduced . we report a case of a 9-year - old boy with  red  scorpion sting who developed acute pulmonary edema and cerebral infarct with motor aphasia . the pathophysiology of this complication is not well known and probably , is the consequence of hypoxia , secondary to respiratory failure , laryngospasm and seizures that are manifestations of envenomatiom by scorpion sting . a 9-year - old male child with a history of  red  scorpion sting was initially admitted at a private clinic where he had one episode of hematemesis and developed pulmonary edema and hypotension . he was later referred to our hospital on day 3 for further management . on admission , the patient was in respiratory distress with heart rate 180 beats / min , respiratory rate 58 cycles / min , oxygen saturation 80% on 5l of o2 , blood pressure 90/70 mmhg with bilateral crepts in the chest and frothing from the mouth . the patient was intubated and was given ventilator care . after hospitalization , the condition of the patient improved and he was extubated 6 h later , but , on day 3 of admission , the patient developed bilateral ptosis and right - sided supranuclear facial palsy with motor aphasia . chest x - ray showing pulmonary edema he was investigated , and showed a hemoglobin level of 11.3 g / dl and total leukocyte count of 9,000/cu mm with 85% neutrophils and 15% lymphocytes , erythrocyte sedimentation rate of 12 mm / h and normal peripheral smear with platelet count of 254,000/l . echocardiography ( ecg ) was performed to rule out cardiac dysfunction , which was normal , and ecg showed rate - related nonspecific st magnetic resonance imaging ( mri ) was done , which showed in flair images , hyperintense areas in the superior , middle and inferior temporal gyri , pre - and post - central gyri and supramarginal and angular gyri on the left side [ figure 2 a and b ] , showing a corresponding area of high signal intensity on diffusion - weighted images indicating restriction of diffusion [ figure 2c ] . these findings are consistent with early infarct and cytotoxic edema in left temporal and parietal lobe in distribution of terminal branches of the left middle cerebral artery . magnetic resonance imaging brain on ( a ) t1 ( b ) t2 weighted and ( c ) flair image shows hyper intense areas in superior , middle and inferior temporal gyri , pre- and post - central gyri , supramarginal and angular gyri on left side after symptomatic treatment and inotropic support , the condition of the patient gradually improved . the patient was discharged in stable condition with persistent motor aphasia on the 8 day of admission . scorpion sting is prevalent in few parts of the world , and is a major health problem in the konkan areas of maharashtra . of 1500 scorpion species , scorpion sting causes a wide range of manifestations , from several local skin reactions to neurologic , respiratory and cardiovascular collapse . the scorpion venom is a water - soluble , antigenic , complex mixture of neurotoxin , cardiotoxin , nephrotoxin , hemolysin , phosphodiesterases , phospholipases , hyaluronidases , histamine , serotonin and other chemicals . by opening sodium channels at the presynaptic nerve terminals and inhibiting calcium dependent potassium channels , the neurotoxin , which is the most potent of the toxins , can cause continuous prolonged , repetitive firing of somatic , sympathetic and parasympathetic neurons . autonomic storm is characterized by transient parasympathetic and prolonged sympathetic stimulation . in most circumstances , the sympathetic response predominates , resulting in sympathetic storm . arterial hypertension , tachycardia , myocardial dysfunction , pulmonary edema and cool extremities have been attributed to stimulation of alpha - receptors by the scorpion toxins . in regard to mechanism of scorpion venom in pathogenesis of respiratory failure and pulmonary edema , comellas et al . concluded that it decreases clearance of alveolar fluid probably secondary to down - regulation of sodium and potassium adenosine tri - phosphatase in the alveolar epithelium . sympathetic complications are not uncommon but central nervous system complications ( cns ) are rare , comprising only 2% of all complications . the toxicity and clinical picture are related to species differences and venom dose / weight relationship . a world health organization publication states that antivenoms are among the few pharmacological agents in widespread use today whose therapeutic value remains largely untested by clinical trials . al - asmari et al . reported that polyvalent antivenom may not be beneficial in all cases of scorpion envenomation , and prazosin may be effective as an alternate . reported the effectiveness of prazosin , demonstrating that the mortality rate was reduced to 1% as compared with 30% in the pre - prazosin era . there has been only one other reported case of motor aphasia as a complication of scorpion envenomation . in cases of envenomation by scorpion sting , the effects on the cns are unclear ; although the penetration of the toxin through the blood - brain barrier is poor , certain authors agree that the toxin acts directly on the neuron , producing encephalopathy and contributing to the occurrence of seizures . an increase in blood pressure secondary to sympathetic stimulation is also mentioned , which could cause hemorrhages , brain edema and cerebral infarction . the acute dyspnea on the night of scorpion sting could have been due to pul==monary edema . the associated hypotension possibly precipitated the cerebral ischemia in the already compromised carotid circulation due to vasospasm . the cerebral infarcts , clinically evident 36 h after envenomation , are compatible with low - flow infarcts , which are known to develop and progress gradually over days or weeks . scorpion sting envenomation is a life - threatening emergency in children and timely referral and early therapy may be life - saving .
scorpion sting is common in villages , and is an important public health problem in india . 
 the clinical symptoms of envenomation by scorpion sting are by sympathetic and parasympathetic stimulation , causing a variety of symptoms . 
 the leading causes of death are cardiac dysfunction and pulmonary edema . 
 we present herein a case of scorpion sting in a 9-year - old boy who developed pulmonary edema and gradually developed cytotoxic cerebral edema with infarct leading to motor aphasia with upper motor neuron facial palsy .