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Spider bite (latrodectism) in Mashhad, Iran
R Afshari1, M Khadem-Rezaiyan, M Balali-Mood
1Medical Toxicology Research Centre, Imam Reza (p) University Hospital, Mashhad University of Medical Sciences, Mashhad, I.R. Iran. AfshariR@mums.ac.ir
Background:
Spider (Latrodectus tredecimguttatus) bites are relatively common in North East Iran. They induce morbidity and rarely mortality. We aimed to investigate clinical, electrocardiographic and para-clinical changes in patients with this bite.
Methods:
All consecutive patients admitted with suspected spider bites between September 2005 and September 2006 were studied prospectively.
Results:
Spider bites accounted for 56 cases (0.5% of all poisoning, 21% of all admitted envenomated). The patients' mean (SD) age was 32 (16) years. The most common findings were pain (90%) mainly in their back (45%), stomach (35%), lower limbs (33%), upper limbs (19%) and chest (14%). Other clinical findings included were sweating (55%), chills (29%), dyspnea (25%), flushing (14%), spasm (12%), headache (12%), nausea (12%) and vertigo (12%). On electrocardiograph (ECG); ST segments were depressed in 25% of cases in at least two of the pre-cordial leads. Laboratory findings were in normal ranges. All the patients recovered following supportive and symptomatic treatment (no anti-toxin available in Iran), with a mean hospitalization period of 1.9 (1.3) days.
Conclusions:
Spider (L. Tredecimguttatus) bite is relatively common in Mashhad, which induces latrodectism with relatively different findings and cardiac toxicity. ECG monitoring should be considered, particularly when specific anti-toxin is not available.
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