Nilton Alves de Rezende

Serum levels of cytokines in patients envenomed by Tityus serrulatus scorpion sting.

Seventeen patients stung by Tityus serrulatus scorpion were classified as mild (pain at the site of the sting, n = 6), moderate (local pain and one of the following manifestations: vomiting, psychomotor agitation, prostration, sweating, tachypnea, tachycardia and mild arterial hypertension, n = 10) and severe cases (equal moderate cases plus cardiac failure, pulmonary edema and shock, n = 1). Venous blood was sampled for biochemical and hematological analysis and for IL-1alpha, IL-6, IL-10, TNF-alpha, IFN-gamma and GM-CSF ELISAs at the time of hospital admission, 6 h (moderate and severe cases), and 12, 18, 36 and 72 h (severe case) later. Ten age-matched healthy volunteers were used as control. Increased serum levels of IL-1alpha was noticed in all patients, high levels of IL-6, IFN-gamma and GM-CSF were observed only in a patient with severe envenomation. Our data suggest that a systemic inflammatory response-like syndrome is triggered during severe envenomation caused by T. serrulatus sting and that release of cytokines may be involved in this response.

Acute pulmonary edema after Tityus serrulatus scorpion sting in children

Acute pulmonary edema due to scorpion toxins has been attributed to acute left ventricular failure resulting from massive catecholamine release or myocardial damage induced by the venom.1–3 It has been proposed that pulmonary edema could also result from increased pulmonary vascular permeability produced by vasoactive substances that may be released by the venom.4 This report presents radiologic, electrocardiographic, enzymatic, echocardiographic and histopathologic evidence that support both cardiogenic and noncardiogenic factors in the pathogenesis of acute pulmonary edema after Tityus serrulatus scorpion sting in children.

Electrocardiographic, enzymatic and echocardiographic evidence of myocardial damage after tityus serrulatus scorpion poisoning

Abstract The cardiovascular manifestations after a Tityus serrulatus scorpion sting consist of arterial hypertension or hypotension, heart failure, pulmonary edema, shock and electrocardiographic changes. 1 Pulmonary edema evoked by scorpion toxin has been attributed to left ventricular failure induced by the venom or to increased pulmonary vascular permeability produced by vasoactive substances that might be released by the venom. 2 The demonstration of myocardial damage and depressed left ventricular systolic function in patients with pulmonary edema following scorpion sting could support the hypothesis that this severe complication is cardiogenic in origin. This report describes results of electrocardiographic, enzymatic and echocardiographic studies in 5 patients with severe envenomation after a Tityus serrulatus scorpion sting.

Immunotherapy for scorpion envenoming in Brazil

Using the ELISA we have shown that in rats subcutaneously injected with Tityus serrulatus scorpion venom there is a fast absorption rate, a fast and high distribution of venom to tissues, a great affinity of the venom for the tissues and a slow elimination half-life. Because of these experimental data, i.v. immunotherapy should be given to patients stung by scorpions as soon as possible after hospital admission. The severity of scorpion envenoming is related to plasma venom concentration (ELISA). The high levels of plasma scorpion venom antigens (ELISA) were cleared 1 h after the infusion of antivenom (5-30 ml of Fab2 fragment) and high concentrations of circulating antivenom persisted for at least 24 h, confirming the efficacy of immunotherapy to neutralise circulating venom. Some symptoms (e.g. local pain and vomiting) decreased 1 h after the starting of immunotherapy, whereas the other symptoms disappeared from 12-48 h later. Using our tripartite approach of treating scorpion envenoming (symptomatic measures, support of vital functions and serotherapy), the mortality rate was very low (0.28%).

Children with adrenergic manifestations of envenomation after Tityus serrulatus scorpion sting are protected from early anaphylactic antivenom reactions.

The incidence of early anaphylactic reactions to scorpion antivenom given i.v. after Tityus serrulatus scorpion sting was evaluated in 103 children aged up to 15 years in Belo Horizonte, Brazil. Patients without adrenergic manifestations (Group 1, n = 28) were compared with those who presented systemic involvement that included adrenergic manifestations (Group 2, n = 75). Data were recorded on a proforma and the presence or absence of early anaphylactic reaction was cross-tabulated according to clinical features, sex, age and volume of antivenom used in the treatment. Unpaired Students t-test was used to calculate significance of differences in age and volume of antivenom used. Multivariate logistic regression was used to determine the effects of clinical features and volume of antivenom as predictors of early anaphylactic reaction to antivenom treatment. Twelve (42.9%) of 28 children included in Group 1 presented early anaphylactic reactions compared with 6 (8%) of 75 children of Group 2 (OR = 8.63; 95% CI: 2.88, 25.7). The reactions were more severe in Group 1. There were no significant differences with respect to age and sex. After adjusting for clinical form, volume of antivenom was not significantly associated with presence of reactions (OR = 1.11; 95% CI: 0.70, 2.80 for each 5.0 ml of antivenom administered). The results show that children with adrenergic manifestations after T. serrulatus scorpion sting had significantly lower anaphylactic reactions to antivenom than those without these manifestations.

Rabdomióilise secundária a acidente ofídico crotálico (Crotalus durissus terrificus)

This paper reports two cases of rhabdomyolysis following Crotalus durissus terrificus snake bite. The diagnosis of rhabdomyolysis was based upon the presence of severe muscle pain and increased blood levels of CPK, GOT and LDH. In case 2 it was confirmed by the detection of myoglobinemia through serum Immunoelectrophoresis carried out against anti-human myoglobin serum and by a muscle biopsy. This patient- also developed acute renal failure following the snake bite. This complication was attributed to the nephrotoxic and he-molytic venom actions and to the arterial hypotension presented by the patient. The possibility that in this case rhabdomyolysis was also involved in the pathogenesis of acute renal failure can not be ruled out. The patient also presented hypocalcemia, hyperuricemia and hyperphosphatemia during the oligoanuric phase of acute renal failure which are laboratory findings associated with rhabdomyolysis.

Comprometimento respiratório secundário a acidente ofídico crotálico (Crotalus durissus)

Sao analisados tres pacientes que apresentaram comprometimento da funcao respiratoria apos acidente por Crotalus durissus. As manifestacoes respiratorias surgiram nas primeiras 48 horas apos a picada do ofidio e consistiram de dispneia, taquipneia, uso da musculatura acessoria da respiracao (casos 1 e 2) e batimento das aletas nasais (caso 2). Dois pacientes (casos 1 e 2) apresentaram insuficiencia respiratoria aguda. O diagnostico desta complicacao no caso 1 foi clinico pois o paciente apresentou apneia. O paciente do caso 2, 24 horas apos o acidente ofidico apresentou dificuldade respiratoria intensa e periodos de apneia sendo intubado, permanecendo em respiracao espontânea. Houve agravamento dos sinais clinicos de insuficiencia respiratoria e a determinacao de pH e gases do sangue arterial mostrou em relacao ao exame inicial elevacao da pressao parcial de gas carbonico (40 mmHg para 50,3 mm Hg) caracterizando insuficiencia ventilatoria aguda. Ambos foram tratados com emprego de ventilacao artificial mecânica, tendo o paciente do caso 1 permanecido no ventilador durante 33 dias e o do caso 2 durante 15 dias. Ambos desenvolveram insuficiencia renal aguda, necessitaram de dialise peritoneal e recuperaram a funcao renal. A paciente do caso 3, apesar dos sintomas e sinais de comprometimento respiratorio nao apresentou alteracoes do pH e gases arteriais. Espirometria realizada 58 horas apos o acidente mostrou capacidade vital forcada (CVF) e volume espirado no primeiro segundo (VEF1) abaixo do previsto (60 e 67% respectivamente). As espirometrias realizadas nos dias subsequentes evidenciaram melhora progressiva destes parâmetros. No 10o dia apos o acidente constatou-se aumento de 20% da CVF e de 17% do VEF1 comparativamente ao exame inicial. A relacao entre VEF1 e a CVF manteve-se praticamente inalterada e em valores proximos ao previsto, caracterizando disturbio ventilatorio do tipo restritivo. O comprometimento respiratorio nestes pacientes foi atribuido a acao da crotoxina na musculatura respiratoria desde que nao se encontravam presentes outras condicoes etiologicas que pudessem ocasiona-lo como uremia avancada, atelectasias, infeccao pulmonar, hipopotassemia, congestao e edema pulmonar agudo.

Afibrinogenemia secundária a acidente ofídico crotálico (Crotalus durissus terrificus)

Relatam se os casos de dois pacientes que desenvolveram afibrinogenemia sem consumo de plaquetas apos terem sido picados por Crotalus durissus terrificus. Ambos tambem tiveram insuficiencia renal aguda de alto debito e no caso no 2 foi feito o diagnostico de rabdomiolise atraves da elevacao expressiva dos niveis sericos de CPK e DHL. O caso no 1 recebeu dose nao especificada de antiveneno e foi tratado com acido epsilon-aminocaproico e transfusao de sangue fresco total tendo apresentado normalizacao dos testes de coagulacao 40 horas apos estas medidas. O caso no 2 recebeu dose adequada de antiveneno crotalico e 12 horas depois ja evidenciava recuperacao do disturbio da coagulacao. O caso no 1 evoluiu sem apresentar hemorragias. O caso no 2 apresentou sangramento persistente nos locais de venoclise e apos remocao de crostas de impetigo nas pernas. Ambos receberam tratamento conservador para a insuficiencia renal aguda e tiveram alta com recuperacao da funcao renal.

Standardization of an enzyme linked immunosorbent assay (ELISA) for detecting circulating toxic venom antigens in patients stung by the scorpion Tityus serrulatus

The sensitivity and specificity of an enzyme-linked immunosorbent assay (ELISA) for the detection of circulating antigens from toxic components of Tityus serrulatus scorpion venom was determined in patients stung by T. serrulatus before antivenom administration. Thirty-seven patients were classified as mild cases and 19 as moderate or severe cases. The control absorbance in the venom assay was provided by serum samples from 100 individuals of same socioeconomic group and geographical area who had never been stung by scorpions or treated with horse antisera. The negative cutoff value (mean + 2 SD) corresponded to a venom concentration of 4.8 ng/ml. Three out of the 100 normal sera were positive, resulting in a specificity of 97%. The sensitivity of the ELISA when all cases of scorpion sting were included was 39.3%. When mild cases were excluded, the sensitivity increased to 94.7%. This study showed that this ELISA can be used for the detection of circulating venom toxic antigens in patients with systemic manifestations following. T. serrulatus sting but cannot be used for clinical studies in mild cases of envenoming since the test does not discriminate mild cases from control patients.

Neurofibromatosis type 1: more frequent and severe then usually thought

OBJECTIVE To study prevalence of clinical features among Brazilian patients diagnosed with neurofibromatosis type 1(NF1), comparing these features with international data to evaluate the severity and visibility of the disease and quantify less frequent manifestations such as short stature, macrocephaly, muscle strength, voice abnormalities and oral motor disorders. METHODS 183 patients diagnosed with NF1, attended at the Neurofibromatosis Outpatient Reference Center, were evaluated for clinical manifestations and complications of NF1. Severity and visibility were verified using the Riccardi and Ablon scales respectively. Voice abnormalities and oral motor disorders were quantified using the Vox-Metria software and maximal voluntary muscle strength (MVMS) was quantified using a handgrip dynamometer. RESULTS Clinical manifestations of NF1 observed were comparable to those described in literature. However, more then 50% of patients presented severity and visibility classified as moderate and severe. The incidence of macrocephaly and short stature was higher among the Brazilian patients. Voice abnormalities and oral motor disorders were quantified for the first time, with hoarseness and oral motor disorders observed in more then 60% the patients. Maximal voluntary muscle strength was found to be reduced in 67% of patients. CONCLUSION The main clinical features of these patients are similar to those reported in previous studies. More then one-half of the patients presented moderate and severe levels of NF1 (severity and visibility), including short stature, macrocephaly, voice abnormalities and oral motor disorders and decreased muscle strength. These results are in disagreement with the traditional concept that NF1 is a benign disease and also disclosed some clinical aspects not previously reported.