Shwartzman reaction in streptozotocin-induced diabetic rats

The possibility that experimental diabetes could prepare for the generalized Shwartzman reaction was investigated in female Sprague-Dawley streptozotocin-induced diabetic rats. After 48 hours, 1 week, and 9 weeks of diabetes, the rats were injected with 2 mg/kg of endotoxin, and the animals were sacrificed 2, 4, 8, and 24 hours after endotoxin. Ninety percent of the diabetic animals given endotoxin developed massive glomerular capillary fibrin deposition accompanied by marked decrease in platelet count. The age- and sex-matched nondiabetic control rats had no such changes. This marked susceptibility to endotoxin, previously only reported in pregnant rats, was present as early as 1 week of diabetes. The degree of glycemic control greatly influenced the susceptibility of diabetic rats to the generalized Shwartzman reaction. Only 28% of the diabetic animals given insulin once daily (4.6 ± 0.3 units, mean ± SEM) and maintaining a blood glucose level of 269 ± 18 mg/dl developed glomerular thrombi. In contrast, the diabetic animals that did not receive insulin and had a blood glucose level of 617 ± 21 mg/dl all developed fibrin thrombi. We conclude that the diabetic state in rats induces a unique susceptibility to the generalized Shwartzman reaction following a single injection of endotoxin, which varies with the severity of the diabetic state. Although the pathogenesis is unclear this phenomenon may reflect abnormalities in the glomerular capillary wall and/or the coagulation system that may be important in the development of microvascular complications. Furthermore, this phenomenon may, in the animal model, mirror the increased risk of the diabetic patient to intravascular coagulation with bacterial sepsis.