versión ISSN 0104-7930
J. Venom. Anim. Toxins v.8 n.1 Botucatu 2002
SPIDER ENVENOMING OF DOG - CASE REPORT
1 Médicos Veterinários Residentes da Clínica de Pequenos Animais da FMVZ-UNESP-Botucatu; 2 Profa. Ass. Dra. do Departamento de Clínica Veterinária da FMVZ-UNESP-Botucatu and 3 Médico Veterinário Aprimorando do Centro de Estudos de Venenos e Animais Peçonhentos-CEVAP-UNESP-Botucatu.
ABSTRACT: This report refers to a female Pinscher treated at the Veterinary Hospital of the Botucatu School of Veterinary Medicine and Animal Husbandry (FMVZ)-São Paulo State University (UNESP), Botucatu, 14 hours after a suspected spider envenoming. The animal showed spastic limbs, dyspnea, salivation, hypothermia, muscular fasciculation, non-responsive mydriasis, and claudication of the right hindlimb. The spider was later identified by the Center for the Study of Venoms and Venomous Animals-CEVAP/UNESP, Botucatu as Phoneutria nigriventer. The treatment with potent analgesic was efficient.
KEY WORDS: Spider envenoming, Phoneutria nigriventer, dog.
Spider envenomings in dogs are very common but definitive diagnosis is very rare. Among spiders of medical interest, those of the genus Phoneutria, known as wandering spider, are considered the most dangerous in Brasil (1). They are responsible for high numbers of spider envenomings registered with the Ministry of Health (1). Between January 1984 and July 1988, envenomings by Phoneutria accounted for 51. 6% out of 647 spider bites registered with the Centro de Controle de Intoxicações (CCI) Hospital das Clínicas Universidade Estadual de Campinas (UNICAMP) (4). These spiders are known as the wandering spider because they assume a characteristic position when they are disturbed. They stand up on their hindlimb keeping the front legs raised (4).
They have aggressive behavior and are highly agile (1,3). The medium body length is 3.5 cm and leg maximum size of 5.0 cm (2).
In São Paulo State, Phoneutria keyserlingi and P. nigriventer (1,2) are the most common species; the latter with black abdomen and body covered with brown and/or yellow short hair (4).
The dorsum has patterns formed by pairs of light spots disposed in longitudinal bands and oblique lines of minor spot towards the lateral side (4) (Figure 1).
|Figure 1. Phoneutria nigriventer|
Spiders have nocturnal behavior, but envenomings occur mainly during the day in domestic environments because they hide indoors, generally inside shoes and clothes. Hands and legs are the most affected sites in humans (4); in the case of dogs, the muzzle area. Spider venom shows peripheral neurotoxic effect, and in humans there is strong local pain, violent muscular spasm, copious lacrimation, salivation, vomiting, priapism, and ejaculation (4).
Severe envenomings may also show bradycardia, arterial hypotension, heart failure, cardiac arrhythmia, shock, dyspnea, neurologic depression of various grades, seizures, acute pulmonary edema, and cardiac and respiratory collapses (4).
The subcutaneous sublethal dose for dogs is estimated to be between 0.18 and 0.2 mg/kg body weight (4).
Treatment is symptomatic in most cases based on local anesthetic blockade with lidocaine without vasoconstrictor. Spider antivenom is indicated when pain reappears after the application of three local infiltrations. Salicylate or dipyrone can be used in severe cases. A case of Phoneutria-bitten canine seen at the Veterinary Hospital of FMVZ-UNESP-Botucatu is presented below.
A two-year-old female Pinscher weighing 2.3 kg was seen at the Veterinary Hospital of FMVZ-UNESP-Botucatu 14 hours after a suspected spider envenoming. The owner related that this animal and two other small dogs were playing with a big spider that was in attack position (raised front legs). A few minutes later, the animal was in lateral recumbency with spastic members, dyspnea, salivation, and hypothermia. The spider identified at CEVAP-UNESP-Botucatu as Phoneutria nigriventer. The dog was taken to a veterinarian that administered corticosteroids, analgesic, anti-histamines, hepatic protector but dosages were not specified. Since the dog did not show any improvement, she was taken to the Veterinary Hospital of FMVZ-UNESP-Botucatu.
The dog showed muscular fasciculation, salivation, dyspnea, non-responsive mydriasis, and partially open eyes. The animal was moderately dehydrated, with hyperemic mucous membranes and hindlimb claudication. The normally quiet dog was reacting aggressively to clinical manipulation.
Ringer® solution and Stimovit® were used for fluid therapy. The dog had brown vomit, exacerbated fasciculations, and altered facial expression for a few minutes. Antiemetic (metoclopramide: 0.5 mg/kg IV) and a potent analgesic (buprenorphine: 0.06 mg/kg IM) were given. The dog also presented pasty brown diarrhea and mild incoordination. The other physical parameters were normal. Hemogram indicated lymphopenia (405 cell/mL). When the dog returned for follow up, it was much better, without muscular fasciculation and the other physical parameters were normal, but still with hyporexia, vomiting, and brown diarrhea. Metoclopramide, dipyrone, and a diet consisting of rice and chicken breast were prescribed. The dog recovered completely after five days of treatment.
Wandering spiders are usually found in domestic environments, however envenomings by them are not usually reported or diagnosed. The above case was typical. According to literature, spider identification and clinical improvement, mainly after analgesic administration, indicate that this case was compatible with Phoneutria envenoming.
1 BARRAVIEIRA B. Venenos: aspectos clínicos e terapêuticos dos acidentes por animais peçonhentos. Rio de Janeiro: EPUB, 1999: 411. [ Links ]
2 BÜCHERL W. Invertebrados: as aranhas. São Paulo: EDART, 1972: 158. [ Links ]
3 BÜCHERL W. Acúleos que Matam: no mundo dos animais peçonhentos. 3. ed. São Paulo: Livraria Kosmos, 1980: 152. [ Links ]
4 SCHVARTSMAN S. Plantas venenosas e animais peçonhentos. 2.ed. São Paulo: Sarvier, 1992: 288. [ Links ]
Received March 21, 2001
Accepted June 26, 2001
M. Sakate - Departamento de Clínica Veterinária UNESP FMVZ Distrito de Rubião Jr. s/n CEP 18618-000, Botucatu, São Paulo, Brasil.