20 First As ia - Pacific Congress

Djenkol bean nephrotoxicity: a preliminary survey in southern Thailand. S. EIAM-ONG and V. SITPRIJA (Department of Medicine, Faculty of Medicine, Chulalongkorn University, Bangkok, Thailand).

BECAUSE of the high consumption of djenkol beans in the southern part of Thailand a survey for djenkolism was made in 6 southern provinces of the country. There were 22 patients with djenkolism. Fifteen were male and 7 were female. Their age ranged from 15 to 57 years. By history the beans were eaten either raw, fried or roasted. The raw beans tended to cause more symptoms than the others, and mature beans were more toxic than young ones. The common symptoms included abdominal colic, lower abdominal pain, dysuria, gross hematuria and anuria. Hypertension was present in 8 patients. All patients had hematuria. Proteinuria was observed in 10 patients, and in 12 patients the serum creatinine was above 1.5 mg/dl. Treatment was supportive and consisted of sodium bicarbonate administration, forced fluid intake and diuretics. Dialysis was performed in only one patient. All patients recovered. Considering the population of southern Thailand and the high consumption of djenkol beans, the problem of toxicity seems small in magnitude and is usually not much realized by doctors and patients. In this respect subclinical cases could easily escape attention. Further study is now being conducted.

Plant poisoning in Sri Lanka. R. FERNANDO (Department of Forensic Medicine, Faculty of Medicine, University of Colombo, Sri Lanka).

SRI LANKA has a very high incidence of poisoning, with over 4000 deaths annually. Plant poisoning, however, is very uncommon and seen mostly in rural areas. Poisoning is usually accidental, but deliberate ingestion for suicidal purposes is known. Homicidal poisoning is rare. The substances responsible for toxicity belong to different chemical groups, sometimes with organ specific toxicity. Various alkaloids, including tropane alkaloids and colchicine, cyanogenic glycosides, cardioactive glycosides, proteins and peptides are the main chemical groups responsible for poisoning. The well documented cases of plant poisoning in Sri Lanka are due to Gloriosa superba, Adenia palmata, Manihot utilissima, Thevetia peruviana, Ricinus communis and Datura fastuosa. Details on toxicity and treatment are now being collected by the author for the proposed Poisons Information Service in Sri Lanka.

The effects o f ciguatoxin on nerve conduction parameters in teleost fish. A. E. FLOWERS, M. F. CAPRA and J. CAMERON (Department of Public Health and Nutrition, Queensland Institute of Technology, GPO Box 2434, Brisbane, 4001 Australia).

CIGUATOXIN (CTX), the principle toxin implicated in ciguatera poisoning, has in recent years been the subject of intense pharmacological research in mammals, and yet to date there has been no comprehensive work to determine why fish remain apparently resistant to this powerful marine toxin. Spinal nerves and the lateral line branch of the vagus nerve were removed from the coral trout (Plectropomus sp.) and the sweetlip (Lethrinus chrysostomus), two fish associated with coral reefs and implicated with ciguatera poisoning in Queensland. Lateral line branches of the vagus were also removed from the whiting (Sillago ciliata), a temperate water fish incapable of carrying the toxin. All nerves exposed to CTX (4.99 × 10 -9 M) displayed a significant increase in the length and amplitude of the supernormal period when compared to nerves exposed to fish Ringer or a non- toxic control extract. Absolute and relative refractory periods were also significantly altered by the presence of CTX. S. ciliata were exposed to veratridine, tetrodotoxin (TTX) and combinations of CTX and TTX. The increase in duration and amplitude of the supernormal period when nerves were exposed to CTX infers that CTX is a Na + channel opener. Although there is no apparent pathophysiological changes in the teleosts which carry ciguatoxin, it has been shown that the nerves of these teleost are just as vulnerable as mammalian nerves to CTX.

The occurrence o f palytoxin in crabs and fish. M. FUKUI, 1 D. YASUMURA, t M. MURATA, l A. C. ALCALA z and T . YASUMOTO l (lDepartment of Food Chemistry, Tohoku University, 1-1 Tsutsumidori-Amamiya, Sendai 980, Japan, and 2Marine Laboratory, Silliman University, Dumaguete City, 6501 Philippines).

THIS investigation was carried out to identify the toxin responsible for highly fatal poisoning due to ingestion of crabs and triggerfish. Xanthid crabs Lophozozymuspictor, Demania alcalai and D. reynaudii, known to cause human fatalities, were collected in the Phillippines. Specimens of the triggerfish Melichthys vidua were collected at Ponape Island, Federated States of Micronesia. The toxin was extracted with methanol and purified by various combinations of chromatographic techniques. Identification of the isolated toxin was carried out by comparing the toxin with reference palytoxin by TLC, HPLC and mass spectrometry. The toxic principles in L. pictor and D. alcalai were unambiguously identified as palytoxin on the basis of chromatographic properties and the mass spectra. The toxins in D. reynaudii and M. vidua were proven to be indistinguishable from