Phospholipase A(2)-induced coagulation abnormalities after bee sting

We will examine the correlation between various bee venom phospholipase A(2 ) (PLA(2)) concentrations and several parameters of coagulation in human pl asma in order to offer a rationale for requesting a particular laboratory c oagulation test after bee sting(s). We will also evaluate in vitro the infl uence of clinically available drugs with a noncompetitive inhibitory effect on PLA(2) on the anticoagulant effect of bee venom PLA(2). Prothrombin ind ex (PTi), partial thromboplastin time (PTT), antithrombin III (AT III), sol uble fibrin monomers (SFM), the activity of coagulation factors I, II, V, a nd VIII, and thrombelastography (TEG) parameters (split point [Sp], reactio n time [R], kinetic time [K], coagulation time [R + K], maximal amplitude [ MA], and the growth angle [alpha]) were determined before and after additio n of 1.4, 2.7, and 4.1 units (1, 2, and 3 mu g protein respectively) of bee venom PLA(2). Linear regression was used to determine the significance of the relationship between these coagulation parameters and bee venom PLA(2) concentrations used. To study the influence of ketamine, lidocaine, magnesi um, furosemide, and cromolyn on the anticoagulant effect of bee venom PLA(2 ), PTi and factor II- and V-activities were measured before and after addit ion of 2.7 units of PLA(2) and PLA(2) plus one of the tested substances. De terminations of F II, PTi, F V,and FVIII showed a negative correlation to b ee venom PLA(2) concentration (r = -0.88, -0.86, -0.81, and -0.79 respectiv ely). A positive correlation was found for PTT (r = 0.69). FII- activity an d PTi correlated better with bee venom PLA(2) concentration than other para meters. F I, AT III, and SFM showed no changes. Whereas Sp, R, and K were p rolonged by bee venom PLA(2) and alpha was reduced, there was no correlatio n to the PLA(2) concentration. Addition of none of the 5 substances could c orrect the effects of bee venom PLA(2) on the coagulation. In a patient wit h toxic reaction or a severe anaphylactic reaction after bee sting(s) we su ggest determinations of FII and/or PTi. This will allow a quick and economi cal assessment of coagulation abnormalities after bee sting(s). Noncompetit ive PLA(2)-inhibitors (ketamine, lidocaine, magnesium, furosemide, and crom olyn) are unable to correct in vitro the anticoagulant effect of bee venom PLA(2). They cannot be recommended at this stage for this purpose. Further investigations with competitive PLA(2)-inhibitors are warranted. Copyright (C) 2000 by W.B. Saunders Company.