Myocarditis and Early Markers of Cardiac Response Associated with Scorpion Stings in Children.

INTRODUCTION: A clinical course ranging from mild local findings to life-threatening systemic findings may occur after scorpion stings. The purpose of this study was to identify priority markers indicating scorpion sting-related cardiac involvement. METHODS: Our study was performed between July 2014, and September 2015 in the Çukurova University medical faculty pediatric emergency department, in Adana, Turkey. Patients admitted with scorpion sting-related cardiac involvement and a control group consisting of patients with no scorpion sting-related cardiac involvement were included in the study. Troponin I at time of presentation and at 6 and 24 h, N-terminal prohormone of brain natriuretic peptide (NTproBNP), ejection fraction as determined by echocardiography at 24 h, and peak and end of T wave (Tp-e) and Tp-e/QTc ratios with echocardiography at 24 h were evaluated. RESULTS: A patient group consisting of 7 cases of scorpion envenomation-related myocarditis and a control group of 30 cases of scorpion intoxication without myocarditis findings were enrolled. Statistically significantly high glucose, white blood cell values, creatine kinase MB, troponin I, and NTproBNP values were identified in the scorpion sting-related myocarditis group (P<0.05). Ejection fractions determined by echocardiography at time of presentation were significantly lower in the patients with myocarditis compared with the control group (P<0.05). A statistically significant difference was identified between Tp-e/corrected QT interval (QTc) ratios investigated in DI and V2 derivations in patient and control group echocardiograms (P<0.05). CONCLUSIONS: We think that use can be made of NTproBNP in addition to echocardiography and troponin I in the early diagnosis of scorpion sting-related myocarditis and that Tp-e and Tp-e/QTc ratios identified via echocardiography can be used as early markers; however, further studies with larger numbers are needed to confirm this.

Acute kidney injury and pancreatitis due to scorpion sting: case report and literature review.

Despite the high number of accidents due to scorpion stings in Brazil, severe cases in adults are seldomly reported. In the Northeast region of Brazil, Tityus stigmurus is the most prevalent species. A 69 year-old woman who was stung by a scorpion attended the emergency room 5 hours after envenomation. She got worse due to abdominal pain. Clinical findings were concordant with class III scorpion envenomation (major systemic manifestations), complicated by acute kidney injury and acute pancreatitis. Intensive supportive therapy was adopted. In the follow-up, 3 months later, she was completely recovered. This report is being brought to recommend the thorough management of victims of scorpion accidents, enabling early diagnosis of severe complications, which could lead to death if aggressive supportive measures are not early and adequately taken.

CD36 Shunts Eicosanoid Metabolism to Repress CD14 Licensed Interleukin-1ß Release and Inflammation.

Interleukin (IL)-1ß is a potential target for treatment of several inflammatory diseases, including envenomation by the scorpion Tityus serrulatus. In this context, bioactive lipids such as prostaglandin (PG)E2 and leukotriene (LT)B4 modulate the production of IL-1ß by innate immune cells. Pattern recognition receptors (PRRs) that perceive T. serrulatus venom (TsV), and orchestrate LTB4, PGE2, and cyclic adenosine monophosphate (cAMP) production to regulate IL-1ß release are unknown. Furthermore, molecular mechanisms driving human cell responses to TsV remain uncharacterized. Here, we identified that both CD14 and CD36 control the synthesis of bioactive lipids, inflammatory cytokines, and mortality mediated by TsV. CD14 induces PGE2/cAMP/IL-1ß release and inflammation. By contrast, CD36 shunts eicosanoid metabolism toward production of LTB4, which represses the PGE2/cAMP/IL-1ß axis and mortality. Of importance, the molecular mechanisms observed in mice strongly correlate with those of human cell responses to TsV. Overall, this study provides major insights into molecular mechanisms connecting CD14 and CD36 with differential eicosanoid metabolism and inflammation mediated by IL-1ß.

Value of troponin levels in the diagnosis of cardiac dysfunction in moderate scorpion envenomation.

CONTEXT: Cardiac dysfunction is one of the most serious consequences of scorpion envenomation. The best tool to evaluate cardiac function is echocardiography, but it is not available at all emergency departments. Many studies aimed to describe biological predictive factors of cardiac dysfunction in scorpion envenomation. Troponin is one of these biomarkers but its correlation with myocarditis is not well established. The aim of this study was to evaluate correlation between troponin levels and cardiac dysfunction in moderate scorpion envenomation. METHODS: A retrospective monocentric study including patients admitted in the emergency department for moderate scorpion envenomation with troponin measurement during their early management. On arrival, an electrocardiogram and a chest X-ray were realized for all patients. RESULTS: We enrolled 132 patients with a mean age at 31.3 ± 24.4 years and a 1.35 sex-ratio. All patients had moderate systemic manifestations. There were 28 patients with clinical manifestations of cardiac dysfunction without life-threatening troubles (21.2%). Troponin was undetectable in 69 patients (56%). The mean value of troponin level (pg/ml) was higher in patients with clinical manifestations of left ventricular dysfunction (1.80 ± 3.8 vs. 0.11 ± 0.5; p = 0.02). Troponin levels were significantly higher in patients with positive T wave on electrocardiogram. CONCLUSION: In patients with moderate scorpion envenomation with positive T wave, high values of troponin suggest the presence of cardiac dysfunction.

The effect of plasmapheresis on treating disseminated intravascular coagulation (DIC) caused by a Hemiscorpius lepturus (Gadim) sting.

INTRODUCTION: The highest mortality from scorpion stings in Iran is due to the stings of a particular type of scorpion known as Hemiscorpius lepturus (H. lepturus, Gadim in local language). The present study aimed at investigating the use of plasmapheresis to treat severe cases of H. lepturus stings. METHOD: This pilot study was a randomized clinical trial conducted from June 2015 to June 2016 in Razi hospital of Ahvaz, Iran. Twenty-nine patients who had been stung by H. lepturus and admitted to ICU because of disseminated intravascular coagulation (DIC) were randomly assigned into control (15 patients, supportive treatments) and plasmapheresis (14 patients, supportive treatments + plasmapheresis) groups, and the patient outcomes were compared between the two groups. FINDINGS: Eighteen patients were female (62%), and the mean of patient age was 24 ± 7. Most of the sting cases had occurred in the torso (15 patients, 52%). Only 10 patients (34%) arrived in the hospital within 12 h of being stung. There was no significant difference between the two groups in terms of the demographic and sting features. In the plasmapheresis group, hemoglobin level was significantly lower, while the PT and INR were measurably higher. In total, the plasmapheresis group experienced 29 sessions of treatment (an average of two sessions for each patient). Overall, 19 patients (66%) expired, whereas 10 patients (34%) experienced recovery with or without complications. The rate of recovery was significantly higher in the plasmapheresis group compared with controls, with eight patients (57%) in the plasmapheresis group surviving compared with two (14%) in the control group (p=.045). The duration of hospitalization was higher in the plasmaphersis group (p < .001). A comparison of the dead and recovered patients' features indicated that the dead patients arrived in the hospital significantly later than the recovered ones, and they also had lower platelet counts. CONCLUSIONS: The findings of this small-scale pilot study show that using plasmapheresis in treating DIC in patients stung by H. lepturus can prevent death and encourage recovery. However, prior to using plasmapheresis as a routine treatment for severe cases of people stung by this scorpion or other similar ones, further controlled studies with a larger sample size are needed.

Role of some vasoactive mediators in scorpion envenomed children: Possible relation to envenoming outcome.

Scorpion envenomation causes an autonomic storm resulting in changes in the vasoactive mediators' levels which lead to myocardial damage, cardiovascular disturbances, peripheral circulatory failure, pulmonary edema, multi-system-organ-failure and death. The study aimed to determine the circulating levels of adrenaline, noradrenaline, angiotensin converting enzyme (ACE), Angiotensin II (Ang II), kallikrein enzyme, nitric oxide (NO), aldosterone, and electrolytes Na+, K+ and Ca+2 in scorpion envenomed children and to evaluate the potential relation between these vasoactive mediators, the severity of scorpion envenoming and the clinical outcome of envenomed children. Forty envenomed children (22 mild and 18 severe cases) along with 10 healthy control children were enrolled in the study. The circulating levels of adrenaline, noradrenaline, Ang II, ACE, kallikrein enzyme, and NO were determined by ELISA, and spectrophotometric assays on admission and 24 h later. On admission, serum aldosterone, and electrolytes; Na+, K+ and Ca+2 were determined by RIA, Flame photometer and Flame atomic absorption respectively. All envenomed children showed significant surge of adrenaline, noradrenaline, ACE, Ang II, aldosterone, NO and Na+, that concomitantly faced by significant reduction in kallikrein, K+ and Ca+2 on admission. Twenty four hours later, all envenomed children continued to show significant elevation of ACE, Ang II and NO. The severely envenomed children showed considerable reduction in circulating levels of adrenaline, noradrenaline, ACE and Ang II, while dramatic increase in kallikrein activity was reported in comparison to mildly envenomed children after 24 h of medical care. Also, NO exhibited considerable accumulation in non survivors, on admission, that was persistent for the subsequent 24 h and was accompanied by high kallikrein, low catecholamines and Ang II levels compared to survivors. Finally, the hypertensive cases showed substantial higher levels of catecholamine, ACE and Ang II, 24 h after admission. These findings indicated that, disturbances of the studied vasoactive mediators were common in scorpion envenomed children and may account for several inflammatory manifestations and clinical outcome. ACE inhibitors could be considered as possible therapeutic agent in victims with prominent increase in ACE and Ang II while kallikrein inhibitor and antioxidants may be effective in the treatment of late hypotensive ones.

Study of severe scorpion envenoming following subcutaneous venom injection into dogs: Hemodynamic and concentration/effect analysis.

To evaluate the dose-effects of Androctonus australis hector (Aah) venom injected subcutaneously on hemodynamics and neurohormonal secretions, 10 anesthetized and ventilated mongrel dogs, were split in two groups (n = 5/group). Subcutaneous injection was done with either 0.2 mg/kg or 0.125 mg/kg of the purified G50 scorpion toxic fraction. Hemodynamic parameters using right heart catheter were recorded and plasma concentrations of catecholamine, troponin, and serum toxic fraction were measured sequentially from baseline to 120 min. We identified the dose of toxic fraction evoking characteristic hemodynamic perturbation of severe envenomation, the time-lapse to envenomation, and the associated plasma level. The injection of 0.125 mg/kg toxic fraction was not associated with significant variations in hemodynamic parameters, whereas the 0.2 mg/kg dose caused envenomation characterized by significant increase in plasma catecholamines, increased pulmonary artery occluded pressure, mean arterial pressure, and systemic vascular resistance (p < 0.05), in association with sustained decline in cardiac output (p < 0.001). Envenomation occurred by the 30th minute, and the corresponding concentration of toxic fraction was 1.14 ng/ml. The current experiment allowed the identification of the sub-lethal dose (0.2 mg/kg) of the toxic fraction of Aah administered by the subcutaneous route. Two parameters with potential clinical relevance were also uncovered: the time-lapse to envenomation and the corresponding concentration of toxic fraction.

General characterization of Tityus fasciolatus scorpion venom. Molecular identification of toxins and localization of linear B-cell epitopes.

This communication describes the general characteristics of the venom from the Brazilian scorpion Tityus fasciolatus, which is an endemic species found in the central Brazil (States of Goiás and Minas Gerais), being responsible for sting accidents in this area. The soluble venom obtained from this scorpion is toxic to mice being the LD50 is 2.984 mg/kg (subcutaneally). SDS-PAGE of the soluble venom resulted in 10 fractions ranged in size from 6 to 10-80 kDa. Sheep were employed for anti-T. fasciolatus venom serum production. Western blotting analysis showed that most of these venom proteins are immunogenic. T. fasciolatus anti-venom revealed consistent cross-reactivity with venom antigens from Tityus serrulatus. Using known primers for T. serrulatus toxins, we have identified three toxins sequences from T. fasciolatus venom. Linear epitopes of these toxins were localized and fifty-five overlapping pentadecapeptides covering complete amino acid sequence of the three toxins were synthesized in cellulose membrane (spot-synthesis technique). The epitopes were located on the 3D structures and some important residues for structure/function were identified.

Scorpion venoms, kidney and potassium.

Scorpion venoms cause renal injury by the interaction of renal ischemia due to intense renal vasoconstriction and inflammatory reactions due to proinflammatory cytokines and mediators. Renal vasoconstriction is not only induced by catecholamine storm but also by angiotensin II and the direct action of venom on vascular ion channels. Increased aldosterone also contributes to hypertension. Blocking of renal tubular K channels decreases renal K excretion and increases serum K level which increases aldosterone release. Hyperaldosteronism increases K excretion mostly through ROMK2 and ROMK3 unblocked by the venom. The presence of angiotensin converting enzyme inhibitor in some scorpion species can increase serum K. Therefore, there are both K increasing and K decreasing effects in renal K excretion. Serum K in scorpionism is the net result of the two opposing effects. Hyperkalemia is therefore inconsistent.

Serum levels of IL-6 and its soluble receptor, TNF-alpha and chemokine RANTES in scorpion envenomed children: their relation to scorpion envenomation outcome.

During the present study, 30 children in Upper Egypt (less than 12 years old) were admitted to Pediatric Intensive Care Unit because of scorpion envenomation. They were compared with 20 apparently normal children of matching age and sex as controls. The victims and controls were subjected to complete clinical examination and full blood picture. The serum levels of interleukin-6 (IL-6), soluble IL-6 receptor (sIL-6R), regulated upon activation normal T cells expressed and secreted (RANTES ) and tumour necrosis factor-alpha (TNF-alpha) were determined once for the controls and twice for the victims, the first sample on admission and the second sample after 24h. All victims showed significantly higher mean values of IL-6, sIL-6R, RANTES, TNF-alpha, and leucocytic count both on admission and on the follow up when compared with controls. According to the clinical manifestations of envenomation, 40% of the victims had a mild envenomation manifestation, while 60% of them had severe manifestations. The severely envenomed children showed significantly higher mean values of IL-6, sIL-6R, TNF-alpha, RANTES and leucocytic count both on admission and on the follow up samples when compared with the mild cases. The non-survival victims (five victims) showed significantly higher mean values of IL-6, sIL-6R, TNF-alpha, RANTES and leucocytic count both on admission and on the follow up samples in comparison to the survivals. Furthermore, those fatal cases showed a non-significant decline in the serum levels of IL-6, sIL-6R, TNF-alpha, RANTES and leucocytic count on the following up samples, while the survivals showed a significant decline in the serum levels of these parameters on the following up samples. In conclusion, these data revealed that IL-6, sIL-6R, TNF-alpha and chemokine, RANTES are involved in the pathogenesis of scorpion envenomation and correlated with its severity.

Best evidence topic report. Scorpion envenomation: does antivenom reduce serum venom concentrations?

A short cut review was carried out to determine if anitvenom reduces serum venom concentrations. Using the reported search, 69 papers were found, of which four presented the best evidence to answer the clinical question. The author, date, and country of publication, patient group studied, study type, relevant outcomes, results, and study weaknesses of these best papers are tabulated. A clinical bottom line is stated.

Significance of assessment of serum cardiac troponin I and interleukin-8 in scorpion envenomed children.

In the present study, 41 children in Upper Egypt were admitted to Pediatric Intensive Care Unit, Assiut University Hospital, for scorpion envenomation. They were compared with 15 apparently healthy children of matching age as controls. The victims and controls were subjected to complete clinical examination, full blood count and arterial blood gases analysis. According to severity of scorpion envenomation, 17 children had manifestations of severe envenomation and clinical signs of toxic myocarditis (severe cases), 14 children had moderate manifestations of envenomation without clinical evidence of carditis (moderate cases) and 10 cases showing only mild symptoms of envenomation (mild cases). The serum levels of cardiac troponin I (cTnI) and interleukin-8 (IL-8) beside the enzymatic activities of creatine phosphokinase (CPK), CPK-isoenzyme-MB (CPK-MB) and lactate dehydrogenase (LDH) were determined once for mild cases and controls on admission and twice for severe and moderate cases on admission and after 24. Electrocardiography and measurements of echocardiographic (Echo) of % fractional shortening of left ventricule (% SF), left ventricular ejection fraction (LVEF) and cardiac chambers dilatation were done for severe and moderate cases. All the envenomed victims showed significantly higher mean values of CPK, CPK-MB, LDH, and IL-8 on admission in comparison to control group. cTnI was not detectable in the sera of control group as well as patients of mild envenomation. The mean values of CPK, CPK-MB, LDH, and IL-8 were significantly higher in severe cases while only IL-8 and CPK-MB were significantly higher in moderate cases in comparison with mild cases. The mean values of IL-8, cTnI, CPK, CPK-MB and LDH were significantly higher in severe cases both on admission and on follow-up comparing with moderate cases. The case fatality rate was 12.5% and all were from severe cases with toxic myocarditis. The non-survivors victims showed significant higher mean values of only cTnI on admission and both cTnI and IL-8 on follow up in comparison to the survivors. Significant reduction of % SF and LVEF were noticed among the non-survivors in comparison to survivors. The cTnI showed 100% specificity and sensitivity for diagnosis of myocardial injury in relation to Echo finding in the envenomed victims. In severe cases, cTnI was positively correlated with IL-8 while negatively correlated with %SF and LVEF. In conclusion, cTnI is a specific marker for diagnosis of myocardial injury in scorpion envenomation while other biochemical markers did not show such specificity. Also, IL-8 may be involved in the pathogenesis of myocardial injury of scorpion envenomation. Both cTnI and IL-8 may be useful to forecast the fatal outcome in scorpion envenomation.

Relationship between plasmatic levels of various cytokines, tumour necrosis factor, enzymes, glucose and venom concentration following Tityus scorpion sting.

A sandwich enzyme-linked immunosorbent assay was developed for measuring Tityus venom levels in plasma. The method proved capable of distinguishing patients with only local symptoms from controls, and was used to quantify venom in 205 accidental human envenomations. Our results show that the severity of envenoming is related to the patient plasma venom concentration. This depends on time elapsed between the sting and when the plasma was drawn. We observed that 46 and 49% of patients with moderate to severe symptoms (MS, n=41) showed hyperamylasemia and hyperglycemia, respectively. In addition, 39% of cases with MS symptoms had partial thromboplastin time values prolonged or shorted and 6.5% of patients with local symptoms (LS, n=164) had only prolonged prothrombin time values. Interleukin 6 (IL6) increased significantly in patients with MS symptoms. IL6 values increased with hyperamylasemia, envenoming severity and time hyperamylasemia.

Increased plasma levels of IL-1beta, IL-6, IL-8, IL-10 and TNF-alpha in patients moderately or severely envenomed by Tityus serrulatus scorpion sting.

Scorpion envenomation is a common medical problem in many countries and an important cause of morbidity and mortality, especially among children. The plasma levels of pro-inflammatory (IL-1beta, IL-6, IL-8 and TNF-alpha) and anti-inflammatory (IL-10) cytokines were measured in individuals stung by Tityus serrulatus (Ts) scorpions. According to clinical manifestations patients were classified, as defined by the Brazilian Ministry of Health, as having mild (n=15, mean age=42.2 years), moderate (n=8, mean age=26 years) or severe (n=4, mean age=14 years) envenomation. Blood samples were taken immediately (T1) and 6h (T2) after admission to the hospital. Eighteen age-matched healthy volunteers were used as control. TNF-alpha, IL-1beta, IL-6 and IL-8 levels were significantly increased in moderate and severe cases and the levels of these cytokines were positively correlated with the severity of envenomation, as evaluated by clinical profile and plasma venom concentration. IL-10 levels were increased in severe and moderate cases and reduced in mild cases. The results reported in the present study suggest that the physiopathological manifestation of Ts envenomation may be mediated, at least in part, by cytokines, and that the early treatment after scorpion sting with drugs that inhibit cytokine production, such as glucocorticoids, may have a potential beneficial effect, ameliorating the severity of the clinical manifestations observed, particularly in severe and moderate cases.

[Rapid immunotitration of individual toxins from Androctonus australis venom]. / Immunodosage rapide des toxines individuelles du venin d'Androctonus australis.

Passive immunotherapy against scorpion envenomations is facilitated by the preliminary titration of circulating toxins in envenomed patients. Currently, routinely used ELISA tests allow only the titration of the whole venom, without reference to the toxins which compose the venom and spread variably within the tissue. Taking as a model one of the three toxins responsible for the lethal effects of Androctonus australis hector (Aahl) venom, we developed an ELISA sandwich test based on a fragment of recombining antibody (scFv) consisting of the variable chains of the monoclonal IgG 9C2 coupled to a decapeptide showing high affinity for streptavidine. Conjugate scFvlStrep-tag was prepared by genetic engineering. It was produced in the periplasm of recombining bacteria, in a reproducible way, in a soluble form, at low cost and with an output, after purification, of 0.8 mg/L of bacterial culture. The recombinant protein, of small size (28 kDa), is bifunctional. It preserves a very high affinity for the toxin Aah I (Kd of 2.3 10(-10) M, very close to that of IgG 9C2), yet recognises streptavidine and its conjugate (streptavidine-peroxidase). The titration of the Aahl toxin used an ELISA sandwich test in which the toxin was captured in a specific way by a monoclonal antibody; the immunocomplexes were then detected by recombinant immunoconjugate, thus conferring a high specificity on titration. The test is quick (90 mn), reproducible and sensitive, with a limit of detection of 0.6 toxin (ng.ml-1). This method could be extended to two other lethal toxins of the venom of the scorpion Androctonus australis hector and to those of other species. New perspectives are thus possible for the diagnosis of the envenomations.

[Clinical evolution and circulating venom levels in scorpion envenomations in Morocco]. / Evolution clinique et taux circulants du venin dans les envenimations scorpioniques au Maroc.

We conducted a clinical and biological study in Morocco in order to assess the efficacy of antivenom therapy against scorpion stings. Epidemiological and clinical data were collected in 275 patients envenomed by Androctonus mauretanicus mauretanicus and Buthus occitanus scorpions. Patients received antivenom or symptomatic drugs. Blood samples were collected upon hospital admission, at 1 hr and 3 hrs after the treatment. An enzyme linked immunosorbent assay (ELISA) was set up to quantify the venom levels in serum of envenomed patients. Mean serum venom concentrations showed an association between clinical signs and the venom level. The venom concentration at admission, in patients who received 10 ml of antivenom, was significantly reduced after antivenom therapy. The decrease was less important in patients who received only 2 to 5 ml of antivenom. No difference was shown in the venom concentration of patients not treated with antivenom. The clinical signs decreased significantly after antivenom treatment. The absence of antivenom administration increased the risk to develop clinical signs at the end of hospitalisation. This risk was much higher when the delay between scorpion sting and hospital admission increased. The results of our study have demonstrated the efficacy of antivenom in reducing circulating venom and symptoms. Antivenom therapy is more efficient when administered as soon as possible after envenomation and with appropriate quantities of antivenom. This study is favourable to the use of SAS but a prospective study would be useful to confirm these data.

Sympathetic nervous system activation, antivenin administration and cardiovascular manifestations of scorpion envenomation.

We performed two-dimensional echocardiograms and determined plasma norepinephrine levels on admission and at 24h after hospitalization, in 16 children with scorpion envenomation. All patients came from areas where scorpions have been identified as Tityus zulianus and received antivenin at the site of the accident or upon admission. Based on the presence or absence of cardiovascular manifestations, patients were divided into two groups. GROUP A: 10 patients had cardiovascular manifestations of pulmonary edema. Four patients had mild pulmonary edema (Left ventricular ejection fraction: 0.43+/-0.19) and six had moderate to severe pulmonary edema (Ejection fraction: 0.31+/-0.09. p=NS, M+/-SD). Plasma norepinephrine was elevated on admission (1279+/-824) and decreased at 24h in seven of eight patients (474+/-140 pg/ml, p<0.03). GROUP B: Six patients had no cardiovascular manifestations. These patients had normal chest X-rays and normal echocardiograms. Plasma norepinephrine was not elevated (188+/-180 pg/ml). Time interval from the accident to antivenin administration was significantly longer in Group A compared to Group B (4.5+/-3.3 vs 1.2+/-0.4h, p<0.03) and correlated directly with the absolute change in plasma norepinephrine (r=0.76, p<001). Consequently, we strongly recommend very early administration of antivenin in the medical management of scorpion envenomation by T. zulianus.

Cardiac troponin I release after severe scorpion envenoming by Tityus serrulatus.

Eight children aged 2-9 years, with signs and symptoms of severe scorpion envenoming by Tityus serrulatus were studied. All patients showed clinical manifestations of cardiac dysfunction, with ECG and echocardiographic alteration and five developed pulmonary edema. Troponin I levels were normal in all patients on admission, except for two who arrived later, and increased thereafter, with maximum values being observed 24-36 h after the sting. The detection of TnI in patients with severe scorpion envenoming, and the observed temporal pattern and serum levels meet the criteria established for the diagnosis of acute myocardial infarction. The rapid reversibility of cardiac dysfunction, together with the normalization of the enzymatic, ECG and echocardiographic data, indicates the occurrence of an acute myocardial lesion without underlying or associated coronary disease.

Scorpion envenomation and serotherapy in Morocco.

A clinical and biologic study was conducted in Morocco to assess the efficiency of antivenom therapy for treating victims of scorpion stings. Epidemiologic and clinical data were collected from 275 patients envenomed by Androctonus mauretanicus mauretanicus and Buthus occitanus scorpions. Patients received antivenom or other drugs. Blood samples were collected at the time of hospital admission and 1 hr and 3 hr after treatment. Serum venom levels were quantified by using an ELISA. An association was found between clinical signs of envenoming and the level of venom in serum. Patients classified as grade II (moderate envenoming) had higher serum levels of venom level than patients classified as grade I (mild envenoming). At admission to the hospital, the mean venom concentration was not significantly different between the group not treated with antivenom, the group who received 2-5 ml of antivenom, and the group who received 10 ml of antivenom. A significant decrease in serum venom levels and an improvement in the clinical conditions were observed in patients administered 10 ml of antivenom. The lower decrease in serum venom levels in patients who received 2-5 ml of antivenom was due to lower doses of antivenom. No difference in the venom concentration was observed in patients who were not treated with antivenom. The absence of administration of antivenom increased the risk of developing clinical signs at the end of the hospitalization period. However, this risk was much higher when more than 1 hr elapsed between the time of the scorpion sting and the time of hospital admission. The results demonstrate that antivenom is effective in decreasing circulating venom and morbidity. Serotherapy is more efficient when given as soon as possible after envenomation and with adequate quantities of antivenom.

Development of an ELISA for the detection of scorpion venoms in sera of humans envenomed by Androctonus australis garzonii (Aag) and Buthus occitanus tunetanus (Bot): correlation with clinical severity of envenoming in Tunisia.

A sandwich ELISA was set up for measuring scorpion venom levels in sera of accidentally envenomed humans with the aim to establish a quantitative relationship between these levels, envenoming severity and clinical symptoms. This assay used equine polyclonal F(ab')2, specific to two North African scorpion (Androctonus australis garzonii: Aag and Buthus occitanus tunetanus: Bot) venoms. The test proved to be simple, reproducible, very sensitive (detection limit = 0.9 ng/ml) and linear between 0.5 and 15 ng/ml of venom concentrations. A large survey on scorpion sting envenomings was conducted from 1993 to 1996 in Tunisia to gather accurate epidemiological, clinical and biological data from victims as well as informations on the treatment that they had received. Victims were classified into three grades (GI, GII and GIII) of increasing severity according to clinical signs of envenoming. Blood samples were collected from victims and tested by ELISA for their content of Aag and Bot venoms. A strong correlation was found between clinical symptoms of envenoming and the level of scorpion venom antigens in serum (r = 0.980). Mean serum venom concentrations were: 2.65 +/- 0.81 ng/ml in GI envenoming, 9.79 +/- 4.08 ng/ml in GII and 21.7 +/- 6.51 ng/ml in GIII. The difference between each group was statistically significant (p < 0.01). This ELISA may prove to be helpful to establish a rationale approach of specific antivenom therapy.