Acta Neuropathol (1995) 89:105-108 9 Springer-Verlag 1995 C. Vital - E. Monlun 9 A. Vital - M. L. Martin-Negrier V. Cales 9 E Leger 9 M. Longy-Boursier. M. Le Bras B. Bloch Concurrent herpes simplex type 1 necrotizing encephalitis, cytomegalovirus ventriculoencephalitis and cerebral lymphoma in an AiDS patient Received: 25 July 1994 / Revised: 19 September 1994 / Accepted: 27 September 1994 Abstract Unlike cytomegalovirus (CMV) ventriculoen- cephalitis, herpes simplex virus type 1 necrotizing en- cephalitis has only rarely been observed in AIDS patients. A 40-year-old bisexual man was followed for an HIV1 in- fection from 1987 onwards. In June 1993 he was referred for sudden confusion, left hemiparesia and fever. The blood contained less than 10 CD4 lymphocytes/mm 3. The patient remained comatose and febrile, and died 4 weeks later. In coronal sections of the brain there was necrosis of the internal parts of the left temporal lobe, necrosis of cer- tain areas of the ventricular walls and a small tumor at the top of the right frontal lobe, which proved to be a poly- morphic high-grade lymphoma. CMV ventriculoencephali- tis lesions were prominent in the ventricular walls of the occipital lobes and there was a strong nuclear signal for CMV using in situ hybridization. Herpes simplex virus type 1 was shown in the nuclei and cytoplasm of certain neurons and astrocytes in the borders of the necrotized temporal lobe areas by immunohistochemistry, in situ hy- bridization and electron microscopy, whereas in situ hy- bridization and immunohistochemistry for CMV were negative in such areas. Necrotizing type 1 encephalitis must not be overlooked in immunodeficient patients. Key words AIDS 9 Cytomegalovirus encephalitis Herpes virus encephalitis 9 Cerebral lymphoma C. Vital 9 A. Vital 9 V. Cales - F. Leger Department of Neuropathology, Bordeaux II University, Bordeaux, France E. Monlun 9 M. Longy-Boursier 9 M. Le Bras Department of Infectious Diseases, Bordeaux II University, Bordeaux, France M. L. Martin-Negrier 9 B. Bloch Department of Histology, Bordeaux II University, Bordeaux, France C. Vital (N~]) Neuropathologie, H6pital Pellegrin, F-33076 Bordeaux Cedex, France Fax: 56-79-60-88 Introduction Herpes simplex virus (HSV) encephalitis has only rarely been reported in patients with acquired immunodeficiency syndrome (AIDS) and the only case of HSV type 1 (HSV1) necrotizing encephalitis with typical temporal distribution has recently been reported in an AIDS patient [14]. We have had the opportunity to observe an AIDS patient who presented a 4-week terminal illness due to a triple pathol- ogy: HSV1 encephalitis with typical temporal lobe necro- sis, cytomegalovirus (CMV) ventriculoencephalitis in the occipital lobes and a small cerebral lymphoma. Case report A 40-year-old bisexual man had been followed for HIV1 infection since 1987. He had been successfully treated for pulmonary pneu- mocystosis in 1991 and cerebral toxoplasmosis in 1992. He was referred to hospital in June 1993 for sudden confusion, left hemi- paresia and fever. The blood contained less than 10 CD4 lympho- cytes/mm3, the cerebrospinal fluid showed no cells and the protein level was normal. The patient remained comatose and febrile and died 4 weeks later. Methods Post-mortem examination was restricted to the brain which was fixed for 3 weeks in 10% formalin. Several large sections from the cerebral hemispheres, cerebellum and brain stem as well as small blocks from numerous areas were embedded in paraffin, and sec- tions were stained with hematoxylin-eosin and Loyez stain for myelin. Immunohistochemistry (IHC) was performed on paraffin-em- bedded fragments (PEF) from necrotized areas of the left temporal lobe and from necrotized walls of the left occipital lobe. Sections were immunostained with antibodies to HSV1 and HSV2 (Dako), which are the purified immunoglobulin fraction of rabbit anti- serum and do not show any cross-reactivity with CMV and Ep- stein-Barr virus (EBV). Monoclonal antibody anti-CMV (E-13, Biosoft) reacts specifically with antigens which are localized in the cell nucleus. Bound antibodies were visualized by the avidin-bi- otin immunoperoxidase technique, according to the supplier's rec- ommended protocol (Dako and Biosoft). Small specimens of for- malin-fixed left temporal lobe were rinsed in cacodylate buffer, re-