SHORT COMMUNICATION Granulomatous amebic encephalitis in a multivisceral transplant recipient O. Mendez a , E. Kanal b , K. M. Abu-Elmagd c , K. McFadden d , S. Thomas b , G. Bond c and S. A. Z ˇ ivkovic ´ a Departments of a Neurology and b Radiology, University of Pittsburgh School of Medicine, Pittsburgh; c Division of Transplantation Surgery, Thomas Starzl Transplantation Institute, University of Pittsburgh School of Medicine, Pittsburgh; and d Department of Pathology (Neuropathology), University of Pittsburgh School of Medicine, Pittsburgh, PA, USA Keywords: Acanthamoeba, encephal- itis, organ transplantation, multivisceral trans- plantation Received 16 November 2004 Accepted 24 February 2005 A 40-year-old man with multivisceral allograft developed acutely right-sided numb- ness 9 months after transplantation. Cranial magnetic resonance imaging (MRI) showed a small left parietal lesion, and cerebrospinal fluid analysis was unremarkable. Stereotactic brain biopsy was non-diagnostic. The patient continued to deteriorate, developed cerebral edema and died at 13 days after the onset of symptoms. Unex- pectedly, autopsy demonstrated acanthamebic encephalitis. This case highlights diagnostic difficulties encountered with amebic encephalitis and expands the spectrum of opportunistic central nervous system (CNS) infections in solid and visceral organ transplant recipients. Introduction Opportunistic central nervous system (CNS) infections complicate the post-transplant clinical course of 5–10% of allograft recipients with high mortality [1–3]. Most commonly, infections are caused by fungi and viruses, while bacterial and parasitic infections are less frequent. Early diagnosis is essential for effective treatment. However, initial diagnosis may be delayed as immunosuppression reduces the inflammatory response, thus blunting typical symptoms of CNS infection, and may even change the characteristic pathology [4]. Amebic CNS infection is quite rare despite their ubiquity, but it is associated with a high mortality in both normal and immunocompromised individuals [5,6]. Two distinct clinical syndromes caused by free-living amebas include primary amebic meningoencephalitis (PAM), and granulomatous ame- bic encephalitis (GAE). PAM is caused by Naegleria fowleri and occurs in healthy individuals with a history of exposure to contaminated freshwater [5,6]. It is usually fatal within a week of onset. GAE is a more insidious infection caused by Acanthamoeba species and Balamuthia mandrillaris. Patients usually follow a subacute to chronic course leading to death within weeks to months [5]. We present a case of fulminant granulomatous amebic encephalitis in a modified multivisceral trans- plant recipient. The pathological findings and radiolo- gical changes are reviewed. Case report Patient is a 40-year-old man who underwent a modified multivisceral transplantation due to Gardner syndrome with large abdominal mesenteric desmoid tumor. The allograft included the stomach, duodenum, pancreas and intestine [7]. The patient was pretreated (precon- ditioned) with 5 mg/kg of intravenous antilymphocyte polyclonal antibodies (Thymoglobulin) and received post-transplant tacrolimus monotherapy [8]. The early post-operative course was complicated with a severe acute graft-versus-host disease (GVHD). Subsequently, the GVHD evolved into a chronic phase with multiple persistent oropharyngeal ulcers. The patient underwent photopheresis with partial response. Nine months after transplantation patient acutely developed right-sided numbness (face, arm, and leg). On examination, the patient was fully oriented with normal speech and language. Eye movements and fundoscopic examina- tion were normal and the face was symmetric. Motor strength and tone were normal. Sensory examination showed decreased sensation to light touch and pin-prick over the right hemibody including face. Laboratory testing showed persistent chronic lymphopenia (CD4+ 30/mm 3 , normal 288–1736; CD8+ 15/mm 3 , normal 133–969), while other tests were normal, including ser- um tacrolimus level. Contrast-enhanced cranial mag- netic resonance imaging (MRI) (day 1), showed left parietal focal sulcal effacement, with an ovoid area of T2 prolongation surrounding an area of abnormal T2 shortening which led to a diagnostic concern of a possible infectious etiology despite the lack of any obvious contrast enhancement (Fig. 1a,b). Lumbar puncture revealed elevated opening pressure of 270 mmH 2 O. Cerebrospinal fluid (CSF) analysis Correspondence: Oscar E. Mendez, MD, 3471 Fifth Ave no. 810, Pittsburgh, PA 15213, USA (tel.: (412) 647-1706; fax (412) 647-8398; e-mail: mendezo@upmc.edu). 292 Ó 2006 EFNS European Journal of Neurology 2006, 13: 292–295