Scorpionism by Hemiscorpius spp. in Iran: a review

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.(AU)

Scorpionism by Hemiscorpius spp. in Iran: a review

Scorpions are distributed throughout Iran and the genus Hemiscorpius is particularly important in this region. Hemiscorpius lepturus is the most significant species within the genus in the country. Since scorpionism provoked by Hemiscorpius comprises a medical emergency, the present study is focused on this important issue. In order to perform the present work, a review of the medical and health-related literature was carried out in several databases. The current findings indicate that six species of Hemiscorpius are found in 15 states of Iran, mainly in the south and southwest. Deaths caused by stings were reported only for two species. The morphological characteristics and geographical distribution of H. lepturus in Iran, its venom and the toxic compounds, epidemiologic data and clinical manifestations of envenomation as well as treatment for affected people are herein reviewed and described. H. lepturus venom toxicity differs from other Iranian scorpions regarding duration and severity. Scorpionism is an important public health problem in Iran, especially in southwest and south regions and in urban areas. It is more prevalent in children and young people. H. lepturus venom is primarily a cytotoxic agent and has hemolytic, nephrotoxic and to some extent hepatotoxic activity. The use of polyvalent antivenom to prevent scorpion sting symptoms is recommended. A well-planned health education program might be useful in preventing scorpionism.

A biodistribution study of Hemiscorpius lepturus scorpion venom and available polyclonal antivenom in rats

The purpose of the present study was to investigate the biodistribution profile of the venom of Hemiscorpius lepturus, the most dangerous scorpion in Iran. Blood and tissue samples were taken at various predetermined intervals during a 400-minute period for the venom and a 360-minute period for the antivenom in rats. The radio-iodination was carried out using the chloramine-T method. The results showed that the descending order of venom uptake was skin, kidneys and intestine, respectively. The descending order of polyclonal antivenom uptake was kidneys, intestine, heart and lungs. The calculated pharmacokinetic parameters of the venom were Telimination half-life = 521.5 ± 12.6 minutes; Vd/F (apparent volume of distribution) = 14.9 ± 3.3 mL; clearance (CL/F, apparent total clearance of the drug from plasma) 0.02 ± 0.005 mL/minute and for the antivenom Telimination half-life = 113.7 ± 7.4 minutes; Vd/F = 13 ± 1.2 mL and CL/F 0.08 ± 0.01 mL/minute. The pharmacokinetics profile comparison of the venom with that of the antivenom shows that serotherapy may be more effective if administered within 2-4 hours following envenomation by H. lepturus.(AU)

A biodistribution study of Hemiscorpius lepturus scorpion venom and available polyclonal antivenom in rats

The purpose of the present study was to investigate the biodistribution profile of the venom of Hemiscorpius lepturus, the most dangerous scorpion in Iran. Blood and tissue samples were taken at various predetermined intervals during a 400-minute period for the venom and a 360-minute period for the antivenom in rats. The radio-iodination was carried out using the chloramine-T method. The results showed that the descending order of venom uptake was skin, kidneys and intestine, respectively. The descending order of polyclonal antivenom uptake was kidneys, intestine, heart and lungs. The calculated pharmacokinetic parameters of the venom were Telimination half-life = 521.5 ± 12.6 minutes; Vd/F (apparent volume of distribution) = 14.9 ± 3.3 mL; clearance (CL/F, apparent total clearance of the drug from plasma) 0.02 ± 0.005 mL/minute and for the antivenom Telimination half-life = 113.7 ± 7.4 minutes; Vd/F = 13 ± 1.2 mL and CL/F 0.08 ± 0.01 mL/minute. The pharmacokinetics profile comparison of the venom with that of the antivenom shows that serotherapy may be more effective if administered within 2-4 hours following envenomation by H. lepturus.(AU)

Integrity in scientific publication

The available Razi Institute antivenom is still, empirically, used by intramuscular (IM) administration for the treatment of scorpion stings in humans by six medically dangerous species including Hemiscorpius lepturus (H. lepturus). The aim of this study was to assess the neutralizing ability and effectiveness of the antivenom in inhibiting hemoglobinuria, biochemical changes, increased microalbuminuria and urinary lactate dehydrogenase (LDH) following H. lepturus sting. Simultaneous intramuscular administration of 10 µL and 100 µL of antivenom, after 24 hours, had no significant preventive effect on the extent and degree of hemoglobinuria or proteinuria produced in venom-treated rats. After IM administration of antivenom, no significant changes in decreased red blood cell (RBC) count and hemoglobin were observed. Immediate intramuscular administration of 10 µL of antivenom had no significant effects on both LDH and microalbuminuria. The present findings did not present correlation with clinical signs. Therefore, to fully assess the efficacy of the available antivenom and make appropriate recommendations, more in vivo or in vitro investigations including antigen-antibody interaction, enzymatic analysis and route-dependent administration are required.(AU)

In vivo pharmacological study on the effectiveness of available polyclonal antivenom against Hemiscorpius lepturus venom

The available Razi Institute antivenom is still, empirically, used by intramuscular (IM) administration for the treatment of scorpion stings in humans by six medically dangerous species including Hemiscorpius lepturus (H. lepturus). The aim of this study was to assess the neutralizing ability and effectiveness of the antivenom in inhibiting hemoglobinuria, biochemical changes, increased microalbuminuria and urinary lactate dehydrogenase (LDH) following H. lepturus sting. Simultaneous intramuscular administration of 10 μL and 100 μL of antivenom, after 24 hours, had no significant preventive effect on the extent and degree of hemoglobinuria or proteinuria produced in venom-treated rats. After IM administration of antivenom, no significant changes in decreased red blood cell (RBC) count and hemoglobin were observed. Immediate intramuscular administration of 10 μL of antivenom had no significant effects on both LDH and microalbuminuria. The present findings did not present correlation with clinical signs. Therefore, to fully assess the efficacy of the available antivenom and make appropriate recommendations, more in vivo or in vitro investigations including antigen-antibody interaction, enzymatic analysis and route-dependent administration are required.(AU)

In vivo pharmacological study on the effectiveness of available polyclonal antivenom against Hemiscorpius lepturus venom

The available Razi Institute antivenom is still, empirically, used by intramuscular (IM) administration for the treatment of scorpion stings in humans by six medically dangerous species including Hemiscorpius lepturus (H. lepturus). The aim of this study was to assess the neutralizing ability and effectiveness of the antivenom in inhibiting hemoglobinuria, biochemical changes, increased microalbuminuria and urinary lactate dehydrogenase (LDH) following H. lepturus sting. Simultaneous intramuscular administration of 10 μL and 100 μL of antivenom, after 24 hours, had no significant preventive effect on the extent and degree of hemoglobinuria or proteinuria produced in venom-treated rats. After IM administration of antivenom, no significant changes in decreased red blood cell (RBC) count and hemoglobin were observed. Immediate intramuscular administration of 10 μL of antivenom had no significant effects on both LDH and microalbuminuria. The present findings did not present correlation with clinical signs. Therefore, to fully assess the efficacy of the available antivenom and make appropriate recommendations, more in vivo or in vitro investigations including antigen-antibody interaction, enzymatic analysis and route-dependent administration are required.(AU)

Clinical and biochemical manifestation produced by scorpion (Hemiscorpius lepturus) venom in experimental animals

Several studies have been published about the clinical and biochemical manifestations produced by the venom of scorpions of the Buthidae family, but very few reports have indicated the manifestations induced by the venom of the Scorpionidae family. Hemiscorpius lepturus is an important scorpion species present in the south and southwestern part of Iran, causing morbidity and mortality in children and adults. For the present study, H. lepturus venom was extracted by electric shock and subcutaneously injected (6.3mg/kg) into a group of six rabbits. Blood collection was carried out before and three hours after venom injection for determination of osmotic fragility and levels of blood sugar, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine phosphokinase (CPK) and alkaline phosphatase (ALP). In vitro studies were also carried out to verify the osmotic fragility of red blood cells (RBCs) exposed to venom concentrations ranging from 0-90µg/2ml blood. Results showed the extreme effect of this venom on the lysis of RBCs both in vitro and in vivo. Venom injection caused significant (p>0.001) increase in ALT, AST, LDH and blood sugar levels. There was also an increase in CPK, and ALP levels after venom injection; however, it was not statistically significant. All animals died four hours after having received the venom. The current study revealed that the neurological effect of H. lepturus venom is similar to that of scorpions of the Buthidae family. However, they differ in RBCs lysis, which was highly significant when induced by H. lepturus venom, probably due to the presence of a type of phospholipase in this venom. Further studies are needed to provide a clearer view of the mechanism of action of H. lepturus venom.

Clinical and biochemical manifestation produced by scorpion (Hemiscorpius lepturus) venom in experimental animals

Several studies have been published about the clinical and biochemical manifestations produced by the venom of scorpions of the Buthidae family, but very few reports have indicated the manifestations induced by the venom of the Scorpionidae family. Hemiscorpius lepturus is an important scorpion species present in the south and southwestern part of Iran, causing morbidity and mortality in children and adults. For the present study, H. lepturus venom was extracted by electric shock and subcutaneously injected (6.3mg/kg) into a group of six rabbits. Blood collection was carried out before and three hours after venom injection for determination of osmotic fragility and levels of blood sugar, alanine aminotransferase (ALT), aspartate aminotransferase (AST), lactate dehydrogenase (LDH), creatine phosphokinase (CPK) and alkaline phosphatase (ALP). In vitro studies were also carried out to verify the osmotic fragility of red blood cells (RBCs) exposed to venom concentrations ranging from 0-90µg/2ml blood. Results showed the extreme effect of this venom on the lysis of RBCs both in vitro and in vivo. Venom injection caused significant (p>0.001) increase in ALT, AST, LDH and blood sugar levels. There was also an increase in CPK, and ALP levels after venom injection; however, it was not statistically significant. All animals died four hours after having received the venom. The current study revealed that the neurological effect of H. lepturus venom is similar to that of scorpions of the Buthidae family. However, they differ in RBCs lysis, which was highly significant when induced by H. lepturus venom, probably due to the presence of a type of phospholipase in this venom. Further studies are needed to provide a clearer view of the mechanism of action of H. lepturus venom.(AU)