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Antivenom therapy for scorpion bites
Toxicon 38 (2000) 1627±1628 www.elsevier.com/locate/toxicon
Letter to the Editor Antivenom therapy for scorpion bites In a recent issue of Toxicon, Gueron and Ilia (1999) point to animal studies with scorpion venom and persistence of respiratory manifestations including pulmonary edema even after 24±48 h of antivenom therapy. They felt that supportive therapy would be the best choice for severely venomated cases. There have been sharply con¯icting and mutually exclusive reports about the ecacy of therapeutic intervention with antivenom from Tunisia (Abroug et al., 1999) and Mexico (Passani, 2000). Surprisingly, there appears to be little concern about the potency of various scorpion antivenom preparations being oered to patients. Potent therapeutic antivenom preparations, crude, Fab or F(ab)2 fractionated, are lyophilized prior to shipping from the premises of the manufacturer. For an optimal performance, they have to be kept refrigerated and used immediately after reconstitution. However, the ®eld performance could not be perfect all the time. That could be reminiscent of the failures recorded with other lyophilized biological products. During the late 1980s, therapeutic administration of antivenom preparations against Russell's viper in the Anurdhapuram area in Sri Lanka was disastrous. Administration of antivenom in 20 patients bitten by Russell's viper failed to clear antigenemia in 19. The antigenemia continued unabated (Phillips et al., 1988). Recently, the state-of-the-art therapy for rabies was a failure in a 9-year-old boy and a 72-year-old woman in Bangkok, Thailand. Postexposure therapeutic intervention with Vero cell derived rabies vaccine and rabies immunoglobin was associated with the development of rabies and death in both cases (Hemachudha et al., 1999). The con¯icting scenario regarding utility of scorpion antivenom therapy (Gueron and Ilia, 1999; Abroug et al., 1999; Passani, 2000) would be resolved only by quanti®cation of antivenom potency in lyophilized and reconstituted lots. Representative lots should be retrieved, fully refrigerated, to the premises of manufacturers or other control laboratories. They should be assayed for the residual antivenom content. In Nigeria, a loss in yellow fever vaccine potency was evident during distribution and storage in remote locations. There was a 0.16 log10 to 0.22 log10 reduction in titer in storage sites. Furthermore, the titer of two vaccine lots that 0041-0101/00/$ - see front matter 7 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 0 4 1 - 0 1 0 1 ( 0 0 ) 0 0 0 9 8 - 2
1628
Letter to the Editor / Toxicon 38 (2000) 1627±1628
had been frozen after reconstitution from their lyophilized state dropped from the initial 3.53 log10 to zero (Adu et al., 1996). An identical scenario with scorpion antivenom might well be responsible for little protection in Tunisia (Abroug et al., 1999) or elsewhere. Any ®nancial input for systematic studies on ®eld potency of antivenom preparations would be costeective. The future antivenoms could be stabilized against the injurious eect of temperature, humidity, etc., by pre-addition of stabilizers. Eorts have been directed at stabilizing live vaccines by the addition of trehalose or deuterium oxide (Brown, 1996). Similar formulations against scorpion stings could be eective universally. References Abroug, F., ElAtrous, S., Nouria, S., et al., 1999. Serotherapy in scorpion evenomation. A randomised control trial. Lancet 354, 906±909. Adu, F.D., Adedeji, A.A., Esan, J.S., Odussanya, O.G., 1996. Live viral vaccine potency: an index for assessing the cold chain system. Public Health 110, 325±330. Brown, F. (Ed.), 1996. New approaches to stabilisation of vaccine potency. Karger, Basel. Gueron, M., Ilia, R., 1999. Is antivenom the most successful therapy in scorpion victims? Toxicon 37, 1655±1657. Hemachudha, T., Mitrabhakdi, E., Wilde, H., et al., 1999. Additional reports of failure to respond to treatment after rabies exposure in Thailand. Clin. Inf. Dis. 28, 143±144. Passani, L.D., 2000. Antivenom for scorpion sting. Lancet 355, 66±68. Phillips, R.E., Threakton, R.D.G., Warrell, D.A., et al., 1988. Paralysis, rhabdomyoloysis and haemolysis caused by the bites of Russell's viper (viper ruselli pulchlla) in Sri Lanka: failure of Indian (Hakine) antivenom. Q. J. Med. 68, 691±716.
Subhash C. Arya Centre for Logistical Research and Innovation, M-122 (of part 2), Greater Kailash-II, New Delhi, 110048, India E-mail address: [email protected]
Letter to the Editor Antivenom therapy for scorpion bites In a recent issue of Toxicon, Gueron and Ilia (1999) point to animal studies with scorpion venom and persistence of respiratory manifestations including pulmonary edema even after 24±48 h of antivenom therapy. They felt that supportive therapy would be the best choice for severely venomated cases. There have been sharply con¯icting and mutually exclusive reports about the ecacy of therapeutic intervention with antivenom from Tunisia (Abroug et al., 1999) and Mexico (Passani, 2000). Surprisingly, there appears to be little concern about the potency of various scorpion antivenom preparations being oered to patients. Potent therapeutic antivenom preparations, crude, Fab or F(ab)2 fractionated, are lyophilized prior to shipping from the premises of the manufacturer. For an optimal performance, they have to be kept refrigerated and used immediately after reconstitution. However, the ®eld performance could not be perfect all the time. That could be reminiscent of the failures recorded with other lyophilized biological products. During the late 1980s, therapeutic administration of antivenom preparations against Russell's viper in the Anurdhapuram area in Sri Lanka was disastrous. Administration of antivenom in 20 patients bitten by Russell's viper failed to clear antigenemia in 19. The antigenemia continued unabated (Phillips et al., 1988). Recently, the state-of-the-art therapy for rabies was a failure in a 9-year-old boy and a 72-year-old woman in Bangkok, Thailand. Postexposure therapeutic intervention with Vero cell derived rabies vaccine and rabies immunoglobin was associated with the development of rabies and death in both cases (Hemachudha et al., 1999). The con¯icting scenario regarding utility of scorpion antivenom therapy (Gueron and Ilia, 1999; Abroug et al., 1999; Passani, 2000) would be resolved only by quanti®cation of antivenom potency in lyophilized and reconstituted lots. Representative lots should be retrieved, fully refrigerated, to the premises of manufacturers or other control laboratories. They should be assayed for the residual antivenom content. In Nigeria, a loss in yellow fever vaccine potency was evident during distribution and storage in remote locations. There was a 0.16 log10 to 0.22 log10 reduction in titer in storage sites. Furthermore, the titer of two vaccine lots that 0041-0101/00/$ - see front matter 7 2000 Elsevier Science Ltd. All rights reserved. PII: S 0 0 4 1 - 0 1 0 1 ( 0 0 ) 0 0 0 9 8 - 2
1628
Letter to the Editor / Toxicon 38 (2000) 1627±1628
had been frozen after reconstitution from their lyophilized state dropped from the initial 3.53 log10 to zero (Adu et al., 1996). An identical scenario with scorpion antivenom might well be responsible for little protection in Tunisia (Abroug et al., 1999) or elsewhere. Any ®nancial input for systematic studies on ®eld potency of antivenom preparations would be costeective. The future antivenoms could be stabilized against the injurious eect of temperature, humidity, etc., by pre-addition of stabilizers. Eorts have been directed at stabilizing live vaccines by the addition of trehalose or deuterium oxide (Brown, 1996). Similar formulations against scorpion stings could be eective universally. References Abroug, F., ElAtrous, S., Nouria, S., et al., 1999. Serotherapy in scorpion evenomation. A randomised control trial. Lancet 354, 906±909. Adu, F.D., Adedeji, A.A., Esan, J.S., Odussanya, O.G., 1996. Live viral vaccine potency: an index for assessing the cold chain system. Public Health 110, 325±330. Brown, F. (Ed.), 1996. New approaches to stabilisation of vaccine potency. Karger, Basel. Gueron, M., Ilia, R., 1999. Is antivenom the most successful therapy in scorpion victims? Toxicon 37, 1655±1657. Hemachudha, T., Mitrabhakdi, E., Wilde, H., et al., 1999. Additional reports of failure to respond to treatment after rabies exposure in Thailand. Clin. Inf. Dis. 28, 143±144. Passani, L.D., 2000. Antivenom for scorpion sting. Lancet 355, 66±68. Phillips, R.E., Threakton, R.D.G., Warrell, D.A., et al., 1988. Paralysis, rhabdomyoloysis and haemolysis caused by the bites of Russell's viper (viper ruselli pulchlla) in Sri Lanka: failure of Indian (Hakine) antivenom. Q. J. Med. 68, 691±716.
Subhash C. Arya Centre for Logistical Research and Innovation, M-122 (of part 2), Greater Kailash-II, New Delhi, 110048, India E-mail address: [email protected]