Russell's viper venom fractions and nephrotoxicity.

Apparently healthy Wistar rats of body weight 250-300 g were chosen for the experiments. A group of 6 rats were assigned for each fraction. The dose of Russell's viper venom (RVV) fraction used for in vivo experiments was 0.75 microgram/g body weight. Of each batch of 6 rats 3 were sacrificed on the third day and the remaining 3 on the fifth day after the administration of test venom fractions. Daily urine output with proteinuria and serum creatinine were determined on the day they were sacrificed. Kidneys from the rats were also examined under light microscopy after hematoxylin and eosin staining. In the in vitro experiment, kidney slices (1 mm thickness) from normal rat was incubated with RVV fractions of 5 mg/ml concentration. The predominant renal lesions observed in both sets of animal experiments were tubular degeneration and necrosis. The changes were mostly confined to proximal tubules. Glomerular changes were mild. Similar tubulotoxic effects were produced by whole RVV as well as single fractions. Therefore, it is possible that RVV contains a common nephrotoxic (protein) component which is present in all fractions of the venom. The renal damage caused by RVV seemed to be due to both systemic effects (mainly DIC and renal ischemia) and direct tubulotoxic effects of the venom.

Acute changes in serum cortisol levels following Russel's viper bites in Myanmar.

Forty-eight Russell's viper bite patients (40 males, 8 females), age ranging from 16-76 years were studied. Out of 48 patients, 14 were found to have a prolonged whole blood clotting time test (WBCT) (i.e. incoagulable blood) (Group 1); 23 had a normal WBCT (i.e. clotted blood) (Group II); and 11 patients had a normal WBCT on admission which changed to non-clotting during the clinical course (Group III). Four patients from group I developed hypotension and 2 expired. The serum cortisol concentration (mean +/- SEM) on admission among groups I and II were 639 +/- 45.6 and 424 +/- 33.2 nmol/l respectively. The blood cortisol level in 35 subjects (controls) were 370.7 +/- 17.7 nmol/l (mean +/- SEM). There was a significant rise of blood cortisol in patients with incoagulable blood when compared to controls at the time of admission to the hospital (p < 0.05); but there was no significant difference among those patients with clotted blood. A much higher mean serum cortisol level was observed in 4 patients with hypotension as compared to 10 patients without shock. These patients with hypotension according to our study shown to have a favorable response to steroid therapy and eventually recovered. Whether higher doses of steroid in addition to antiserum confer extra benefit in suppressing nonspecific venom effects on the pituitary and/or adrenal is not known.

Urinary fibrin (-ogen) degradation products in Russell's viper (Daboia russelii siamensis) bite victims.

Serum and urine concentrations of fibrin (-ogen) degradation products (FDP) were estimated in 20 proven Russell's viper bite (RVB) cases with severe defribination. All patients had similar degrees of high serum FDP levels. However, the ten who developed into acute renal failure (ARF) had significantly (p < 0.001) higher urinary FDP levels than those who did not. The urinary FDP levels of ARF cases increased correspondingly with high serum FDP levels but not in cases without ARF. Serial comparison of serum and urinary FDP levels in RVB cases with severe defibrination may be of value in predicting the likelihood of developing ARF. The present study favored disseminated intravascular coagulation as the main cause of ARF in Myanmar RVB cases.