Hongos Contaminantes

Australasian Mycologist (2009) 28, 23–28

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A near-fatal case consistent with mushroom poisoning due to Amanita species
Bettye J. Rees , Richard Cracknell , Adam Marchant and David A. Orlovich
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School of B.E.E.S., University of New South Wales, Sydney 2052, Australia. Author for correspondence. Email b.rees@unsw.edu.au. Director, Emergency Department LiverpoolHospital; Network Director, Liverpool/Macarthur Emergency Departments; Conjoint lecturer, 3 University of New South Wales. National Herbarium of NSW, Botanic Gardens Trust, Mrs Macquaries Road, Sydney, NSW 2000, 4 Australia. Department of Botany, University of Otago, PO Box 56, Dunedin 9054, New Zealand.

Abstract
Although some Amanita species are consumed in Australia without apparent illeffect, the “death cap” mushroom, Amanita phalloides (Vaill.:Fr.) Link, which occurs mostly in association with broad-leaved trees such as Oak, has been responsible for several fatalities or severe mushroom poisonings in the Australian Capital Territory and Victoria. A recent near-fatal mushroom poisoning in the Sydney region suggests other Australian Amanita species may be involved. This recentcase, occurring in a south-east Asian community on the outskirts of Sydney, may have resulted from ingestion of a native Australian species superficially similar to the paddy-straw mushroom, Volvariella volvacea (Bull.:Fr.) Singer which shares many features with Amanita species in the button stage. Although no material other than Amanita ochrophylla (Cooke & Massee) Cleland was recovered from theremains of a meal consumed by the patient, a new species Amanita volvarielloides B.J. Rees is described which was found at the site four days after the accidental poisoning. Morphological and molecular evidence is presented for this new species, to explore relationships with known causes of Amanita poisonings from both hemispheres. Key words: Amanita, Australia, poisoning, Allocasuarina, LSU.Introduction The incidence of severe mushroom poisoning in Australia has been low (Barbato 1993). This is due in part to the innately conservative attitude towards mushroom eating of our early Anglo-Celtic forebears (Southcott 1996), and to the fact that the most poisonous mushroom Amanita phalloides (the “death cap”), does not occur natively in Australia. It grows in a mutually beneficial associationwith exotic plants such as oak, hazelnut and chestnut (Read pers. comm.) and occasionally liquid-amber, birch and beech (Cole 1993) forming a mycorrhiza with host plants, which have been introduced into Australia over many years. With changing ethnic composition, more experimental eating habits and more wide-spread sightings of A. phalloides in the ACT, Tasmania, Victoria, and recently SouthAustralia, the incidence of mushroom poisoning has increased, and several fatalities have been documented (Trim et al. 1999; Brine 2002). A second species, Amanita preissii (Fr.) Sacc., has also been implicated in mushroom poisoning (Cleland 1943; Harris & Stokes 1976; Southcott 1996). In general, however, edibility of most native Australian mushroom species of fungi is untested (Southcott 1996). Theonset of symptoms of mushroom poisoning may vary depending on the identity of the mushroom, the amount ingested, the nature of the toxic principle involved and the length of exposure to the toxin (Barbato 1993). Some Amanita species can produce extremely toxic cyclopeptides including amatoxins and phallotoxins (Vetter 1998). Where amanitin is the principal toxic factor, in species such as A.phalloides, the initial onset of symptoms may be delayed up to 24 hours followed by a symptom-free latent period of a further 24 hours before onset of hepatic and renal failure occur (Barbato 1993).

If symptoms are not recognized early, this delay reduces the chance of a successful recovery from the poisoning. Not all Amanita species are poisonous. Some species such as Amanita caesarea (Scop.:Fr.)...