Funnel-web spider bite: a systematic review of recorded clinical cases.
OBJECTIVE
To investigate species-specific envenoming rates and spectrum of severity of funnel-web spider bites, and the efficacy and adverse effects of funnel-web spider antivenom.


METHODS
Cases were identified from a prospective study of spider bite presenting to four major hospitals and three state poisons information centres (1999-2003); museum records of spider specimens since 1926; NSW Poisons Information Centre database; MEDLINE and EMBASE search; clinical toxinology textbooks; the media; and the manufacturer's reports of antivenom use.


METHODS
Patient age and sex, geographical location, month, expert identification of the spider, clinical effects and management; envenoming was classified as severe, mild-moderate or minor/local effects.


RESULTS
198 potential funnel-web spider bites were identified: 138 were definite (spider expertly identified to species or genus), and 77 produced severe envenoming. All species-identified severe cases were attributed to one of six species restricted to NSW and southern Queensland. Rates of severe envenoming were: Hadronyche cerberea (75%), H. formidabilis (63%), Atrax robustus (17%), Hadronyche sp. 14 (17%), H. infensa (14%) and H. versuta (11%). Antivenom was used in 75 patients, including 22 children (median dose, 3 ampoules; range, 1-17), with a complete response in 97% of expertly identified cases. Three adverse reactions were reported, all in adults: two early allergic reactions (one mild and one with severe systemic effects requiring adrenaline), and one case of serum sickness.


CONCLUSIONS
Severe funnel-web spider envenoming is confined to NSW and southern Queensland; tree-dwelling funnel webs (H. cerberea and H. formidabilis) have the highest envenoming rates. Funnel-web spider antivenom appears effective and safe; severe allergic reactions are uncommon.
Isbister
Geoffrey K
GK
Menzies School of Health Research, Charles Darwin University, Darwin, NT. gsbite@ferntree.com
Gray
Michael R
MR
Balit
Corrine R
CR
Raven
Robert J
RJ
Stokes
Barrie J
BJ
Porges
Kate
K
Tankel
Alan S
AS
Turner
Elizabeth
E
White
Julian
J
Fisher
Malcolm McD
MM
D000328:Adult; D000818:Animals; D000997:Antivenins / Q000008:administration & dosage* / Q000009:adverse effects; D002648:Child; D003430:Cross-Sectional Studies; D006306:Health Surveys; D006801:Humans; D009517:New South Wales / Q000453:epidemiology; D015876:Northern Territory / Q000453:epidemiology; D011073:Polyamines / Q000037:antagonists & inhibitors / Q000633:toxicity*; D011446:Prospective Studies; D011793:Queensland / Q000453:epidemiology; D013045:Species Specificity; D001098:Spider Bites / Q000175:diagnosis / Q000188:drug therapy / Q000453:epidemiology*; D014904:Western Australia / Q000453:epidemiology
D000997:Antivenins; C071920:FTX, spider toxin; D011073:Polyamines