Cerebral toxoplasmosis and Guillain‐Barré syndrome after allogeneic peripheral stem cell transplantation

Abstract: We report an unusual case of cerebral toxoplasmosis associated with Guillain‐Barré syndrome ( GBS) in a 25‐year‐old patient diagnosed with chronic myelogenous leukaemia ( CML), who underwent a mismatched allogeneic peripheral stem cell transplantation ( PSCT). On day +83 he started with fever, and 7 days later tremor, muscular weakness, diplopia, dysarthria, respiratory difficulty, and universal arreflexia appeared, compatible with GBS. As the patient had a positive cytomegalovirus ( CMV) antigenemia, this was the aetiology suspected for his neurologic findings, but specific treatment failed to improve his clinical situation, and he died on day +123. Necropsy demonstrated cerebral toxoplasmosis and axonal degeneration of nerve roots compatible with the axonal form of GBS. Interestingly, the polymerase chain reaction ( PCR) signal for Toxoplasma gondii in two different cerebrospinal fluid ( CSF) samples had been negative. In addition, this case showed unique magnetic resonance imaging ( MRI) abnormalities. We conclude that a negative PCR on CSF cannot exclude toxoplasmosis in a transplant patient, and we emphasise the importance of considering Toxoplasma as an aetiology of fever and neurological symptoms in the transplant setting.