Levamisole adulterated cocaine and pulmonary vasculitis: Presentation of two lethal cases and brief literature review

The first case reports of levamisole-related disease in cocaine users were published in 2010, although levamisole adulteration of cocaine was first recognized several years earlier. Currently, more than 70% of street cocaine seizures, in the US and the EU, contain levamisole, which could potentially be converted to aminorex, though the reasons for this practice still remain obscure. Here we report two fatal cases of isolated pulmonary vasculitis in abusers of levamisole-adulterated cocaine, where a complete autopsy, full toxicological analysis by gas chromatography-mass spectrometry (GC-MS) using a previously published method of Karch et al. and histological examination were performed. A control group composed of 11 cases of cocaine related deaths, where the presence of levamisole was excluded in blood, urine and hair, was used. Recent literature on the human pharmacokinetics of levamisole and aminorex is also reviewed. The toxicological analysis revealed positive qualitative and quantitative results for cocaine, benzoylecgonine and levamisole in both cases. In case 1 levamisole was found at the concentration of 13.5 and 61.3mg/L in blood and urine respectively, whereas in case 2 at 17.9 and 70.2mg/L. The histological examination highlighted in case 1 in heart samples microscopic evidence of the typical remodeling changes associated with chronic stimulant abuse, whereas lungs showed numerous lymphocytes surrounding and infiltrating the wall of small pulmonary vessels and a perivascular fibrosis with transforming fibroblasts. In case 2, the myocardial samples showed wide fields of myocardial necrosis characterized by hypercontraction of the myocytes with thickened Z-lines and short sarcomeres, whereas lung samples showed a significant intimal thickening of arteriole walls and lymphocytic infiltration of the wall and edema. Moreover, there were also numerous perivascular lymphocytic infiltrates. Although the pathological cardiac findings have allowed us to establish the cause of death in both cases, the presence of pulmonary vasculitis in the lungs represent a further complication. If the disease had progressed to hemorrhage, it certainly would have been a contributory cause of death. The two cases here reported allow us to advance a hypothesis about the possible correlation between the consumption of levamisole adulterated cocaine and pulmonary vasculitis and the comparison of these findings with the control group support this hypothesis. However, this hypothesis is still weak, taking into consideration the fact that pulmonary vasculitis was detected in 2 cases only, making it impossible to exclude a different etiology of this finding. Only through careful histological lung examinations of further cases of fatalities, related to levamisole adulterated cocaine, can this hypothesis be confirmed or refuted.