Antivenom for snakebite envenoming in Sri Lanka: the need for geographically specific antivenom and improved efficacy.

Sri Lanka is a tropical developing island nation that endures significant economic and medical burden as a result of snakebite envenomation, having not only a high prevalence of envenomations, but also one of the highest incidence rates (200 snakebites/100,000 people/year) of venomous snakebite in the world (Kasturiratne et al., 2005). Ironically, the very snakes responsible for this human morbidity and mortality are a valuable biomedical and ecological national resource, despite the medical and economic consequences of envenomation. Currently, no snake antivenom is produced using venoms from native Sri Lankan snakes as immunogens, and there is a true need for an efficacious Sri Lanka, poly-specific snake antivenom. An approach to fulfilling this need via combining the scientific, technological and economical resources from Costa Rica and the United States with the knowledge and talent of Sri Lankan official governmental agencies, legal counsels, environmental, medical and veterinary academic institutions, and religious and cultural leaders has been initiated, coordinated and funded by Animal Venom Research International (AVRI), a nonprofit charity. This bridging of nations and the cooperative pooling of their resources represents a potential avenue for antivenom development in a developing country that suffers the consequences of few specific resources for the medical management of venomous snakebite. The desired final outcome of such an endeavor for Sri Lanka is, most importantly, improved medical outcomes for snakebite patients, with enhanced and expanded science and technology relating to snake venoms and antivenoms, and the collateral benefits of reduced economic cost for the country.

Is fresh frozen plasma effective for thrombocytopenia in adults with dengue fever? A prospective randomised double blind controlled study.

RATIONALE: Thrombocytopenia is a common problem which causes concern and complications in dengue fever. If proven effective, intravenous fresh frozen plasma is a simple and widely available therapeutic option to manage thrombocytopenia. OBJECTIVE: To test the efficacy of fresh frozen plasma (FFP) on thrombocytopenia in patients with dengue fever. DESIGN: 109 serologically confirmed dengue patients with platelet counts <40 000/mm3 were randomised into two groups. Group A (treatment) comprised 53 patients and group B (control) 56 patients. Group A received an intravenous infusion of 3 units (600 ml) of FFP over 90 minutes. Group B received an intravenous infusion of an equal volume of isotonic saline over the same period. The primary outcome measure was the difference between pre- and post-interventional platelet counts at 12, 24 and 48 hours. RESULTS: Following Intervention, the mean platelet count was significantly higher in Group Athan in Group B at 12 hours (p=0.04; t-test). The mean platelet counts continued to be higher in Group A than in Group B at 24 and 48 hours post-intervention, but the differences were not statistically significant. CONCLUSIONS: In dengue patients with thrombocytopenia, infusion of 600 ml FFP may contribute to a significant increase in platelet count in the first 12 hours, but not thereafter.

An outbreak of Aspergillus meningitis following spinal anaesthesia for caesarean section in Sri Lanka: a post-tsunami effect?

An outbreak of Aspergillus fumigatus meningitis occurred in 5 women following spinal anaesthesia, performed between 21 June and 17 July 2005 for caesarean section, in Colombo, Sri Lanka. The patients' median age was 27 years. Different teams in 2 maternity hospitals gave spinal anaesthesia. Mean incubation period was 11.2 days. Fever, headache and nuchal rigidity were common presentations. Remittent fever continued despite broad-spectrum intravenous antibiotics. Papilloedema, lateral rectus palsy, cerebral infarction and haemorrhage developed later. Three patients died. Cerebrospinal fluid pleocytosis with low glucose yielded negative PCR for fungi. Fungal cultures subsequently grew Aspergillus fumigatus. A post-mortem of the first patient confirmed Aspergillus meningitis, followed by treatment with amphotericin B and voriconazole, that saved the lives of others. Visual and hearing impairment in one and complete recovery in the other were observed a year after treatment. Examination of unused plastic syringes, needles, cannulae, and ampoules of anaesthetic agents confirmed that 43 syringes from three different manufactures were contaminated with Aspergillus fumigatus. The stores for drugs and devices of the Ministry of Health were examined and found to be full of tsunami donations, while regular procurements of the Ministry were kept in a poorly maintained humid warehouse. Inadequate space for tsunami donations was identified as the most plausible explanation for sub-optimal storage. Withdrawal and incineration of all unused syringes controlled the outbreak. The survival of those aggressively treated for Aspergillus meningitis suggests in hindsight that the availability of diagnostic tests and specific treatment, and early recognition of the outbreak could have saved the lives of victims who died. Early life-threatening side-effects and permanent long term sequelae of antifungal medication stress the need to be cautious with empirical treatment in immuno-competent low-risk individuals.

Acute myocardial infarction in a patient with Russell's viper bite.

We describe a previously healthy patient who developed and acute anterolateral Q wave myocardial infarction after a Russell's viper bite. Severe chest pain persisted despite intravenous morphine and polyspecific antivenom therapy. The pain subsided with intravenous heparin. The patient recovered.

Efficacy of antivenom in the treatment of severe local envenomation by the hump-nosed viper (Hypnale hypnale).

In Sri Lanka, the usual treatment for severe local envenomation by the hump-nosed viper (Hypnale hypnale) is with polyspecific snake antivenom. We carried out a prospective, randomized, placebo-controlled, single-blind clinical trial to determine the efficacy and safety of polyspecific snake antivenom in the treatment of severe local envenomation by this snake. Sixty-three patients with signs and symptoms of local envenomation by the hump-nosed viper Lanka were randomized to receive either polyspecific snake antivenom or normal saline. The two groups were similar in age, sex, time of presentation to hospital, and degree of envenomation. There was no significant difference between the antivenom and placebo groups in the time taken for complete resolution of the local envenomation (5.52 days versus 4.77 days; P = 0.53, by the Mann-Whitney U test). There was a 44.82% incidence of adverse reactions associated with treatment with antivenom. We conclude that polyspecific snake antivenom is not indicated for severe local envenomation by the hump-nosed viper.

Intravenous immunoglobulin in the treatment of snake bite envenoming: a pilot study.

The standard treatment for snake bite envenoming is with snake antivenon (AVS). Reports to date on the efficacy of AVS have been equivocal. Some studies have shown a beneficial effect on the coagulopathy, while its effect on neurotoxicity is questionable. AVS therapy is also associated with a high incidence of reactions. We conducted a pilot study to compare the standard AVS therapy, with AVS plus intravenous immunoglobulin (IVIG), in the treatment of snake bite evenoming. Our study indicates that the addition of IVIG to the standard AVS regimen, eliminates the need to repeat AVS for envenoming associated with coagulopathy.

Envenomation by the hump-nosed viper (Hypnale hypnale).

We carried out a prospective clinical study from June to December 1993 at the Base Hospital in Avissawella, Sri Lanka to determine the clinical features of envenomation by the hump-nosed viper (Hypnale hypnale). Sixty-two consecutive adult patients (63% males and 37% females, with a median age of 30 years [age range 13-68 years]) admitted to the medical unit following hump-nosed viper bites were surveyed. Most (85.48%) of the patients were bitten on the feet, while 14.52% of the patients were bitten either on the hands or forearms. Most (61.29%) of the patients were bitten during the evening hours (6:00-10:00 PM). The mean time for admission to the hospital following the bite was 1.5 hr (range 0.25-13 hr). All patients had signs of local envenomation manifested by pain, swelling, and induration at the site of the bite, which was occasionally associated with local hemorrhagic blister formation (11.29%) and regional lymphadenopathy (24.19%). None of the patients had signs of systemic envenomation.