Clinical features and management of Hadronyche envenomation in man

Using case reports and a review of the literature, the clinical features of envenomation by the genus of Australian funnel web spiders known as Hadron yche are characterised. Five cases are reported here, including the first l ife-threatening envenomation by Hadronyche species 14 (the Port Macquarie f unnel web). Two severe envenomations by Hadronyche cerberea (the Southern T ree funnel web) and one each by Hadronyche formidabilis (the Northern Tree funnel web) and Hadronyche infensa (the Darling Downs funnel web) are also described. The clinical experience of the authors' provided the five cases described in detail one of which has previously been reported in brief. Eig ht cases of Hadronyche envenomation from the literature (Medline 1966-1998 and Embase 1980-1998) were analysed in order to draw comparisons between th is syndrome and the well described envenomation syndrome of Atrax robustus (the Sydney funnel web). Reports of funnel web spider antivenom use to Comm onwealth Serum Laboratories (CSL) between 1995 and June 1998 were also exam ined. The biology of these dangerous spiders, their geographic distribution , venom characteristics and management issues are addressed. It is conclude d that bites from at least six Hadronyche species have produced a life-thre atening envenomation syndrome clinically indistinguishable from that of Atr ax robustus. Atrax robustus derived antivenom is effective although antiven om requirements may be greater than for Atrax envenomation. Antivenom suppl ies are limited and sufficient stocks to treat a severe envenomation are un likely to be found in any one institution. Pressure-immobilisation first ai d is effective in delaying onset of envenomation, may enhance local inactiv ation of venom and early removal can result in rapid clinical deterioration . (C) 1999 Elsevier Science Ltd. All rights reserved.