Persistent coma in Strongyloides hyperinfection syndrome associated with persistently increased ivermectin levels.

TO THE EDITOR—We share an interesting clinical case that impacts on the treatment of Strongyloides hyperinfection syndrome. A 64-year-old man was admitted to our intensive care unit for postoperative care after aortic valve replacement. His previous medical history was relevant for giant cell arteritis for which he was using prednisone. Three days postoperatively, severe sepsis with multiorgan failure developed. Sputum was collected, and high numbers of mobile Strongyloides stercoralis larvae were observed and a diagnosis of S. stercoralis hyperinfection syndrome with dissemination was made. Ivermectin therapy, first orally and later subcutaneously, was initiated. Although numbers of live Strongyloides decreased rapidly and his clinical condition improved, he remained in a persistent vegetative state and the patient died. Given the fact that other causes for a persistent coma were excluded, we suspected that neurotoxicity of ivermectin might have been responsible for the persistent coma. Ivermectin is generally a safe drug that does not accumulate even in high dosages when given to healthy volunteers [1]. However, cases of encephalopathy have been reported [1, 2], which is associated with coma in animals [3, 4]. To analyze whether drug accumulation was present