Geoffrey K Isbister1, Michael R Gray. 1. Discipline of Clinical Pharmacology, University of Newcastle, Level 5, Clinical Sciences Building, Newcastle Mater Misericordiae Hospital, Waratah, NSW 2298. gsbite@bigpond.com
Abstract
OBJECTIVE: To determine the spectrum of severity and early diagnostic predictors of redback spider bites (Latrodectus hasselti), and to examine the effect of intramuscular redback antivenom. DESIGN AND SETTING: Prospective cohort study of calls to New South Wales, Queensland and Western Australian poisons information centres and presentations to Royal Prince Alfred Hospital and Royal Darwin Hospital emergency departments. PATIENTS: 68 people with definite redback spider bites in which the spider was immediately collected and expertly identified (1 February 1999 to 30 April 2002). INTERVENTIONS: Intramuscular redback spider antivenom in a smaller cohort of hospitalised patients. MAIN OUTCOME MEASURES: Pain severity and duration, local effects and systemic envenomation (effects, prevalence, and persistence > 24 hours). RESULTS: The median duration of effects was 48 hours (interquartile range, 24-96 hours). Pain occurred after all bites and was severe in 42 (62%). Forty-five patients (66%) had pain lasting longer than 24 hours, and 22 (32%) were unable to sleep because of pain. Systemic effects occurred in 24 (35%). Increasing pain over one hour occurred in 37 cases (54%), and local/regional diaphoresis in 23 (34%); both these features were highly predictive of L. hasselti bites compared with bites of other spiders. One of six patients treated with intramuscular antivenom (17%) had no pain at 24 hours, compared with two of 17 untreated patients (12%) (difference, 5%; 95% CI, -36% to +64%; P = 0.95). There was no difference in duration of systemic effects with antivenom administration. CONCLUSIONS: Most redback spider bites cause severe and persistent effects. Intramuscular antivenom appears to be less effective than previously thought and its use by this route needs review.
OBJECTIVE: To determine the spectrum of severity and early diagnostic predictors of redback spider bites (Latrodectus hasselti), and to examine the effect of intramuscular redback antivenom. DESIGN AND SETTING: Prospective cohort study of calls to New South Wales, Queensland and Western Australian poisons information centres and presentations to Royal Prince Alfred Hospital and Royal Darwin Hospital emergency departments. PATIENTS: 68 people with definite redback spider bites in which the spider was immediately collected and expertly identified (1 February 1999 to 30 April 2002). INTERVENTIONS: Intramuscular redback spider antivenom in a smaller cohort of hospitalised patients. MAIN OUTCOME MEASURES: Pain severity and duration, local effects and systemic envenomation (effects, prevalence, and persistence > 24 hours). RESULTS: The median duration of effects was 48 hours (interquartile range, 24-96 hours). Pain occurred after all bites and was severe in 42 (62%). Forty-five patients (66%) had pain lasting longer than 24 hours, and 22 (32%) were unable to sleep because of pain. Systemic effects occurred in 24 (35%). Increasing pain over one hour occurred in 37 cases (54%), and local/regional diaphoresis in 23 (34%); both these features were highly predictive of L. hasselti bites compared with bites of other spiders. One of six patients treated with intramuscular antivenom (17%) had no pain at 24 hours, compared with two of 17 untreated patients (12%) (difference, 5%; 95% CI, -36% to +64%; P = 0.95). There was no difference in duration of systemic effects with antivenom administration. CONCLUSIONS: Most redback spider bites cause severe and persistent effects. Intramuscular antivenom appears to be less effective than previously thought and its use by this route needs review.
Authors: Geoffrey K Isbister; Margaret O'Leary; Mark Miller; Simon G A Brown; Sharmaine Ramasamy; Rosemary James; Jennifer S Schneider Journal: Br J Clin Pharmacol Date: 2007-08-09 Impact factor: 4.335
Authors: Robert A Haney; Thomas H Clarke; Rujuta Gadgil; Ryan Fitzpatrick; Cheryl Y Hayashi; Nadia A Ayoub; Jessica E Garb Journal: Genome Biol Evol Date: 2016-01-05 Impact factor: 3.416