[Tityus asthenes scorpion stings: epidemiological, clinical and toxicological aspects].
BACKGROUND
Scorpion stings are a public health problem in many countries. However, in Colombia, very few epidemiological, clinical or toxicological studies have been undertaken.


OBJECTIVE
Ecological and epidemiological aspects were related to the prevalence of scorpion stings by Tityus asthenes. The clinical features of envenomization were described in patients and in an experimental animal model.


METHODS
The study was conducted in four localities of Mutatá and Urabá Counties in the province of Antioquia, Colombia. The sample consisted of 1,593 (929 urban, 664 rural) of the 5,305 exposed people, inhabitating 324 households (188 urban (58%); 136 rural (42%) of 1,448 houses total in the study area. An interview survey was performed in every selected family for a more realistic estimate of sting prevalence. Additionally, a prospective study was directed toward patients presenting scorpion stings at care at the local hospital over an 18-month period.


RESULTS
The probability was 12.9 times greater of finding T. asthenes inside or around houses in places near to forest and high agrarian plantations (odds ratio = 13). Eighty scorpion stings were reported in the retrospective study (4.1% prevalence [95% CI 3.3-4.8%] ), but only 14 of the patients (17.5%) sought care in the local hospital (an 82.5% underreportage). Seventy percent of the stings occurred in rural places; 50% occurred in the locality of Caucheras, with an attack rate of 10.6%. The overall household infestation rate was 269% (95% CI 22.9-30.8%) and an area dispersion ratio of 100%. Signs of systemic envenomization occurred mainly in children (67%). The 50% lethal dose of T. asthenes venom was 121.6 µg for 18-20 g Swiss Webster rats (95% CI 103.7-139.6). Immunodetection of T. asthenes and Centruroides gracilis/C.margantatus venoms in the experimental animals was possible when were tested by Western blot against Alacramyn (Instituto Bioclón, México) and Soro antiaracnídico (Instituto Butantan, Brasil) antivenoms. Scorpion interspecific differences were noted.


CONCLUSIONS
The prevalence of stings by T. asthenes were common and their presence was associated with tropical rainforests. Envenomization at low density can be neutralized efficiently by anti-scorpion antivenoms produced in México and Brazil but with differing specificities for the venom of each scorpion species.
Gómez
Juan P
JP
Grupo de Ofidismo/Escorpionismo, Corporación Académica para el Estudio de Patologías Tropicales, Universidad de Antioquia, Medellín, Colombia.
Quintana
Juan C
JC
Arbeláez
Patricia
P
Fernández
Jorge
J
Silva
Juan F
JF
Barona
Jacqueline
J
Gutiérrez
Juan C
JC
Díaz
Abel
A
Otero
Rafael
R
D000293:Adolescent; D000328:Adult; D000368:Aged; D000818:Animals; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D051379:Mice; D008875:Middle Aged; D011446:Prospective Studies; D012189:Retrospective Studies; D065008:Scorpion Stings / Q000175:diagnosis* / Q000453:epidemiology*; D012604:Scorpion Venoms / Q000506:poisoning; D012605:Scorpions; D055815:Young Adult
D012604:Scorpion Venoms