Primer registro de una picadura causada por un macho de Latrodectus geometricus C. L. Koch, 1841 (Araneae: Theridiidae) / First record of a bite produced by a male of Latrodectus geometricus C. L. Koch, 1841 (Araneae: Theridiidae)

Latrodectus geometricus (Araneae: Theridiidae), es una araña llamada vulgarmente "viuda marrón". Originaria de África, es una especie sinantrópica y cosmopolita, muy frecuente en varias ciudades del centro y norte de Argentina. A diferencia de otras especies del género no suele causar envenenamientos graves, habiéndose registrado en el mundo muy pocos casos que requirieron tratamiento los cuales evolucionaron siempre de forma favorable. Todos los casos registrados hasta la fecha fueron atribuidos a hembras, asumiendo que los machos no causan casos clínicos e incluso serían incapaces de atravesar con sus quelíceros la piel humana debido a su pequeño tamaño. Este trabajo presenta el primer registro de un accidente causado por un macho de L. geometricus describiendo los síntomas. El accidente ocurrió a una mujer de 21 años en Villa Gobernador Gálvez (33°01'31" S, 60°38'01" O), Santa Fe, Argentina, en marzo 2016. El ejemplar murió en el momento siendo conservado y luego identificado según su genitalia como un macho adulto de L. geometricus. Los síntomas se relevaron desde el accidente hasta el cese de las manifestaciones sin intervención terapéutica. En el momento la joven advirtió una sensación punzante seguida inmediatamente de ardor y eritema. Luego de 10 minutos el ardor aumentó, disminuyendo a los 20 minutos. Luego de una hora el ardor y el eritema disminuyó considerablemente. Los resultados observados respaldan que L. geometricus no reviste peligrosidad en Argentina y evidencian que los quelíceros de los machos pueden atravesar la piel humana, al menos en zonas de piel delgada.

Latrodectus geometricus (Araneae: Theridiidae) is a spider commonly known as "Brown widow". Originally from Africa, is a synanthropic and cosmopolitan spider, very common in several cities in central and northern Argentina. Unlike other species of the genus, this spider does not cause serious poisoning, very few have been registered that required treatment and always evolved favorably. All cases listed to date were attributed to females, assuming that males do not cause clinical cases and would even be unable to pass through human skin due to the small size of their chelicerae. This work presents the first record of an accident by a male of L. geometricus and describes the symptoms. The accident occurred to a 21 year old woman from Villa Gobernador Gálvez (33°01'31" S, 60°38'01" W), Santa Fe, Argentina, in March 2016. The specimen died at the time, being preserved and then identified as an adult male of L. geometricus according to its genitalia. The symptoms were relieved from the accident to its end without applying treatments. At the time, the woman felt a sting followed immediately by burning sensation and erythema in the area. After 10 minutes the burning increased, decreasing at 20 minutes. One hour later, burning sensation disappeared and the erythema diminished considerably. The observed results support L. geometricus as not dangerous in Argentina and show that males actually are able to penetrate the human skin, at least in areas of thin skin.

Complicaciones Neurológicas De Las Mordeduras De Arañas / Neurological Complications Of Spider Bites

Resumen Las arañas son artrópodos venenosos de distribución global. La mordedura de la mayoría de las arañas no tiene trascendencia clínica, debido a la dificultad que éstas tienen de inyectar veneno a los seres humanos por el pequeño tamaño de sus quelíceros. A pesar de esto, existen cientos de casos reportados con envenenamiento secundario a mordedura de arañas. El cuadro clínico es pleomórfico, aunque pueden distinguirse tres síndromes principales: latrodectismo, loxoscelismo y envenenamiento por la araña de "tela en embudo". El latrodectismo se debe a una neurotoxina llamada alfa-latrotoxina presente en el veneno de las "viudas negras" (latrodectus sp). El cuadro cursa con dolor intenso en el sitio de la mordedura, y la complicación sistémica más común es la hipertensión arterial. Las complicaciones neurológicas consisten en cefalea, letargia, irritabilidad, mialgias, temblor, fasciculaciones, ataxia o parestesias. Estas últimas se relacionan con liberación excesiva de neurotransmisores colinérgicos a nivel de la unión neuromuscular. El loxoscelismo es causado por arañas de la familia Sicariidae, géneros Loxosceles y Sicarius. Existen dos tipos de presentación, la cutánea (cambios limitados al área de piel afectada) y la víscerocutánea. En esta última, puede ocurrir coagulopatía severa, asociada o no a insuficiencia renal aguda, ictericia, fiebre, falla multiorgánica y shock. El veneno de las arañas "tela de embudo" tiene potentes neurotoxinas llamadas delta-atracotoxinas, las que simulan neurotransmisores liberados por vesículas pre-sinápticas, causando hiperestimulación de los receptores pos-sinápticos, lo que resulta en alteraciones sensitivas y parálisis muscular. También pueden desarrollarse alteraciones del sistema nervioso simpático y parasimpático, tales como diaforesis, sialorrea, hipotensión arterial y arritmias cardiacas.

Abstract Spiders are venomous arthropods with worldwide distribution. Most spider bites are clinically insignificant, as the size of their chelicerae is too small to inject enough amount of venom to human beings. Despite this, there are hundreds of reported cases of human envenoming related to spider bites. While clinical manifestations related to spider-bite envenoming are pleomorphic, three main clinical syndromes could be recognized: latrodectism, loxoscelism, and funnel-web spider envenoming. Latrodectism is caused by the potent neurotoxin (-latrotoxin present in the venom of widow spiders (Latrodectus sp.). Most cases present with severe pain at the site of the bite, with arterial hypertension being the most frequent systemic manifestation. Neurological complications mostly consist of headache, lethargy, irritability, generalyzed myalgia, tremor, fasciculations, ataxia, or paresthesias. The latter manifestations are related to an exhaustive release of cholinergic neurotransmitters at the neuromuscular junction. Loxoscelism is caused by envenoming by spiders of the family Sicariidae, genera Loxosceles and Sicarius. It presents in two different forms, cutaneous (with changes restricted to the affected skin) area and viscerocutaneous. In the latter, a severe coagulopathy may occur, associated or not with acute renal failure, jaundice, fever, multi-organ failure and shock. The venom of fennel-web spiders have potent neurotoxins, called (-atracotoxins, that stimulates neurotransmitter release from the presynaptic vesicle, causing hyperstimulation of post-synaptic receptors resulting in sensory disturbances and muscle paralysis. Also, sympathetic and parasympathetic manifestations, including diaphoresis, hypersalivation, arterial hypotension, and cardiac arrhythmias may occur.

Latrodectismo. Caso clínico y revisión de la literatura / Latrodectism Case report and review of literature

El latrodectismo es un cuadro clínico causado por la mordedura de una araña del género Latrodectus spp., ampliamente distribuido en todo Chile continental. Generalmente las mordeduras se asocian a faenas agrícolas. El veneno del género Latrodectus contiene α-latrotoxina, una neurotoxina que actúa a nivel presináptico del sistema nervioso autónomo aumentando la liberación de acetilcolina. El cuadro clínico es inespecífico y hasta en un tercio de los casos ocurren síntomas sistémicos. El diagnóstico es clínico y depende del antecedente de la mordedura por una araña con un cuadro clínico compatible. El pronóstico es favorable: se reporta una letalidad entre 0 y 6 por ciento. El manejo es esencialmente sintomático, principalmente analgésico. Presentamos el caso de un hombre de 62 años, proveniente de Santa Cruz, VI región, trabajador en una plantación de trigo. Consultapor dolor torácico asociado a mialgias generalizadas y diaforesis. Por sospecha de latrodectismo, se administra neostigmina con buena respuesta clínica.(AU)

Latrodectism is a clinical entity caused by the bite of a spider of the genus Latrodectus spp. widely distributed throughout continental Chile. Generally, bites are associated with agricultural activities. The venom of spiders of the genus Latrodectus contains α-latrotoxin, a neurotoxin that acts at the presynaptic level of the autonomic nervous system, this way increases the release of acetylcholine. The clinical manifestations are non-specific and systemic symptoms occur in up to one-third of the cases. The diagnosis is clinical and depends on the history of being bitten by a spider with a compatible clinical presentation. The prognosis is favorable: a lethality between 0 and 6 percent has been reported. The clinical management is essentially symptomatic, mainly analgesic. We present the case of a 62-year-old man from Santa Cruz, VI region, working in a wheat farm. He attends the emergency service with chest pain associated with generalized myalgias and diaphoresis. On suspicion of latrodectism, neostigmine is administered with goodclinical response. (AU)

Latrodectismo en la provincia de Jujuy: Aspectos epidemiológicos y clínicos / Latrodectism in the province of Jujuy: Epidemiological and clinical aspects

En Argentina, las especies de arañas de importancia sanitaria pertenecen a los géneros Loxosceles, Phoneutria y Latrodectus. El objetivo del presente trabajo fue relevar los accidentes producidos por el género Latrodectus atendidos en el centro de referencia y derivación provincial de animales venenosos de Jujuy (Hospital San Roque) en el período: 1 de enero de 1998 al 31 de diciembre de 2014. En los diecisiete años analizados se registraron 30 historias clínicas con diagnóstico de latrodectismo, el 83 % de los casos procede de zonas semiáridas y áridas de la provincia de Jujuy. Se registró un valor medio de 1.8 casos/año; la mayoría de los accidentados (63 %) fueron de sexo masculino y la franja etaria más afectada se ubicó entre 16-25 años (50 %). La visualización del arácnido fue confirmada por 18 pacientes, de los cuales el 67 % (n=12) lo identificó como "huayruro" o "viuda negra". Entre las manifestaciones clínicas predominaron: dolor local, dolor generalizado, dolor abdominal, diaforesis e hipertensión arterial. El periodo de internación fue corto (2,7 días) y no hubo complicaciones ni óbitos. Este es el primer estudio clínico-epidemiológico de latrodectismo en el noroeste argentino.

In Argentina, the species of spiders of sanitary importance belong to the Loxosceles, Latrodectus and Phoneutria genera. The objective of this study was to survey accidents caused by the spiders of Latrodectus genus treated at the Jujuy provincial venomous animal reference and referral center (San Roque Hospital) between January 1, 1998 and December 31, 2014. In the seventeen years analyzed, 30 medical records with a diagnosis of latrodectism were analyzed, 83% of the cases came from semi-arid and arid areas of the province of Jujuy. An average of 1.8 cases/year was established. Most of the injured (63%) were male and the most affected age group was between 16-25 years (50%). The arachnid depiction was confirmed by 18 patients, of which 67% (n=12) identified it as "huayruro" or "black widow". Predominant clinical manifestations were local pain, generalized pain, abdominal pain, diaphoresis and hypertension. The length of hospitalization was short (2,7 days) and there were no complications or deaths. This is the first clinical-epidemiological study of latrodectism in northwestern Argentina

LATRODECTISMO

Se denomina latrodectismo al síndrome de emponzoñamiento por mordedura de arañas del género Latrodectus. El agente causal en América es Latrodectus mactans, conocida como "viuda negra", "araña del trasero colorado" y "araña del trigo". A continuación reportamos el caso de un paciente de 47 años, cuyo cuadro es producto de la mordedura de Latrodectus mactans, consideramos relevante este caso ya que debemos conocer las características clínicas de este síndrome, caso contrario podríamos vernos inmersos en una amplia gamma de posibilidades diagnósticas que van desde un abdomen agudo, tétanos, pancreatitis, hasta un infarto agudo de miocardio.

It names latrodectismo to the syndrome of poisoning for bite of spiders of the kind(genre) Latrodectus. The causal agent in America is Latrodectus mactans known as"black widow","spider of the coloured(red) back" and "spider of the wheat". Later we report the case of a 47-year-old patient, whose picture is a product of the bite of Latrodectus mactans, consider this case to be relevant since we must know the clinical characteristics of this syndrome, opposite case we might meet immersed in a wide gamma of possibilities that go from a acute abdomen, tetanus, pancreatitis, up to a acute heart attack of myocardium.

First case of human latrodectism in Venezuela / Primeiro caso de latrodectismo humano na Venezuela

The first case of envenoming by Latrodectus geometricus in Venezuela is described. The accident occurred at the victim’s home, in Aragua de Barcelona, Anzoátegui State. The 31-year-old female victim was bitten twice on the left scapular region, in quick succession (within seconds). She developed a hyperactive state of the central, autonomic and peripheral nervous systems with minor local symptoms.

Descreve-se o primeiro caso de envenenamento por Latrodectus geometricus na Venezuela. O acidente ocorreu na residência, em Aragua de Barcelona, Estado Anzoátegui. A paciente de 31 anos de idade foi picada, consecutivamente duas vezes, em segundos, na região escapular esquerda. Ela desenvolveu um quadro de hiperatividade do sistema nervoso central, autonômico e periférico com escassa sintomatologia local.

Relato de um caso de latrodectismo ocorrido em Manaus, Amazonas, Brasil / Report of a case of latrodectism occurring in Manaus, Amazonas, Brazil

Em 02/07/1995, foi atendido no Instituto de Medicina Tropical do Amazonas, paciente masculino, 11 anos, acidentado em Manaus, por picada na região retroauricular direita, clínicamente compatível com aquele causado por Latrodectus. Observavam-se abalos musculares, febre, calafrios e sudorese intensa. Instituída terapêutica com neostigmine precedido de atropina, gluconato de cálcio, cimetidina, diazepam e hidrocortisona. No terceiro dia apresentava-se melhorado, consciente, orientado e com diminuição importante do edema palpebral. A despeito de uma melhora progressiva diária, no quinto dia surgiu eritema máculo-pápulo-vesiculoso. Em 14/07/1995 teve alta, assintomático. O caso relatado é o primeiro descrito na região Amazônica, ocorrido na periferia de Manaus e pode ter sido uma consequência da expansão urbana das duas últimas décadas.

In July 2, 1995 arrived at the Instituto de Medicina Tropical do Amazonas as eleven-year-old male with complaining of spider bite on his right retroauricular region, presenting typical findings of latrodectism. The accident was reported as having occurred in the suburbs of Manaus. The patient was given neostigmine preceded by atropine, calcium gluconate, cimetidine, diazepan and hydrocortisone. Within three days the patient showed improvement, and was aware, orientated and with significant palpebral oedema reduction. Muscle spasms are still present, as well as fever, shivering, and intense sweating. In spite of a daily progressive improvement, at the fifth day appeared a spotted papular erythema. The patient was discharged without symptoms after the 13th day. This is the first such reported case which took place in Amazonian region, it might have been happened a consequence of the urban sprawl which has characterized the growth of the city of Manaus, in the last twenty years. It is not possible at this point to evaluate the epidemiological resound of the event, but in any case, it seems plausible to recommend that black widow antivenom become available.