J Neurol Neurosurg Psychiatry 1999;67:789–792 789 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.6.789 on 1 December 1999. Downloaded from SHORT REPORT Human herpesvirus 6 in cerebrospinal fluid of patients infected with HIV: frequency and clinical significance Simona Bossolasco, Roberta Marenzi, Helena Dahl, Luca Vago, Maria Rosa Terreni, Francesco Broccolo, Adriano Lazzarin, Annika Linde, Paola Cinque Abstract convulsions or other neurological symptoms The objective was to evaluate the fre- complicating exanthema subitum.2–4 HHV-6 quency of human herpesvirus 6 (HHV-6) encephalitis or milder neurological symptoms DNA detection in the CSF of patients have been described in both immunocompet- infected with HIV and its relation to brain ent adults and transplanted patients,5–7 and the disease and systemic HHV-6 infection. virus might also play an aetiological part in Nested polymerase chain reaction multiple sclerosis.8 HHV-6 has also been found (PCR) was used to analyse CSF samples in the brain or CSF of adults and children with from 365 consecutive HIV infected pa- AIDS, but its role in neurological disease is still tients with neurological symptoms. When unclear.9–12 available, plasma and brain tissues from To study the possible relation between patients whose CSF was HHV-6 positive HHV-6 and brain disease in patients infected were also studied. with HIV, the presence of HHV-6-DNA in the HHV-6 was found in the CSF of eight of CSF was assessed in a large group of patients copyright. Division of Infectious the 365 patients (2.2%): two had type A with neurological disease and was correlated Diseases, San RaVaele and four type B; the HHV-6 variant could with clinical and neuropathology patterns. Hospital, Via Stamira not be defined in the remaining two. All d’Ancona 20, 20127 eight patients had neurological symptoms Milano, Italy S Bossolasco and signs related to concomitant oppor- Patients and methods R Marenzi tunistic brain diseases, including cytome- The CSF of 365 consecutive patients infected F Broccolo galovirus (CMV) encephalitis in five with HIV admitted to San RaVaele Hospital in A Lazzarin patients whose CSF was also positive for P Cinque the period 1992–6, was prospectively examined CMV-DNA. Opportunistic infections but for the presence of HHV-6-DNA by polymer- no other unexplained lesions were also Pathology Unit, San ase chain reaction (PCR). All patients included RaVaele Hospital, Via found in the brain of all of the four in the study had CNS symptoms or signs at a http://jnnp.bmj.com/ Olgettina 60, 20132 patients who underwent neuropathologi- physical examination and no contraindications Milano, Italy cal examination. Both HHV-6 and CMV for undergoing a lumbar puncture. Clinical M R Terreni were also detected in the plasma of neurological, neuroradiological, and CSF ex- respectively five and seven of seven amination, also including DNA-PCR for the Pathology Unit, Luigi patients whose CSF was HHV-6 positive. Sacco Hospital, Via identification of herpes simplex virus type 1 GB Grassi 74, 20157 In conclusion, HHV-6 type A or B DNA and 2 (HSV-1, HSV-2), Varicella zoster virus Milano, Italy was infrequently found in the CSF of HIV (VZV), cytomegalovirus (CMV), Epstein-Barr L Vago infected patients, in association with both virus (EBV), and JC virus (JCV)11 were done at on September 24, 2021 by guest. Protected CMV brain infection and systemic HHV-6 the onset of clinical manifestations. The CSF Department of replication. However, no certain relation Virology, Swedish findings relating to 286 of these patients have between HHV-6 and brain disease was 11 Institute for Infectious been presented previously. In patients whose Disease Control and found. CSF was positive for HHV-6-DNA, all of the Microbiology and (J Neurol Neurosurg Psychiatry 1999;67:789–792) available CSF and plasma samples drawn at or Tumor Biology Center, Keywords: HIV infection; human herpesvirus type 6; after the onset of neurological manifestations, Karolinska Institute, ° 17177 Stockholm, cerebrospinal fluid; cytomegalovirus and kept stored at -80 C, were retrospectively Sweden examined. HHV-6 PCR was also applied to H Dahl CSF and plasma samples taken from 20 A Linde Human herpesvirus 6 (HHV-6), variants A neurologically asymptomatic HIV seronegative and B, is a ubiquitous lymphotropic virus. controls (patients who had undergone spinal Correspondence to: Dr Paola Cinque email HHV-6 B is known to be the causative agent anaesthesia) and to plasma samples drawn [email protected] of exanthema subitum, but both variants have from 22 HIV infected patients with other CNS been found in immunocompromised patients.1 diseases whose CSF was HHV-6-DNA nega- Received 10 March 1999 and Clinical evidence supports a role for HHV-6 tive. In all patients the CSF samples were in revised form 25 June 1999 in causing significant CNS disease. The virus is drawn for diagnostic purposes and all of the Accepted 22 July 1999 often found in the CSF of children with febrile patients and controls gave their informed con- 790 Bossolasco, Marenzi, Dahl, et al J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.6.789 on 1 December 1999. Downloaded from M 12345678910 423 bp 195 bp 176 bp Agarose gel electrophoresis of amplification products after nested PCR for HHV-6 DNA using the standard assay, which amplifies a 173 bp DNA fragment (lanes 1–5) or the subtype PCR assay, which amplifies a 195 bp DNA fragment for group A and a 423 bp DNA fragment for group B (lanes 6–10). M=100 bp DNA ladder marker; lanes 1, 6=HHV-6 variant A positive CSF (patient 1 of the table); lanes 2, 7=HHV-6 variant B positive CSF (patient 2 of the table); lanes 3, 8=DNA-free control; lanes 4, 9=HHV-6 variant A positive control (GS strain); lanes 5, 10=HHV-6 variant B positive control (Z29 strain). sent for the CSF sampling in an approved blindly with respect to the patients’ history in manner. the 365 prospectively examined patients. A nested PCR for HHV-6-DNA detection Postmortem CNS examinations were per- was carried out as previously described.6 The formed in three patients (time interval between positive samples were also tested by another the CSF sampling and necropsy was 1–90 PCR assay which gives products of diVerent days), and brain biopsy in one. The postmor- sizes for the HHV-6 A and B variants, allowing tem examinations involved eight standard copyright. their diVerentiation (“subtype” PCR, figure).13 tissue sections and sections from any other The analytical sensitivity was estimated to be macroscopically visible lesion.11 Tissues were 20 and 50 HHV-6 genomes for the standard fixed in formalin, embedded in paraYn, and and the subtype PCR, respectively.6 Pre-PCR examined after haematoxylin and eosin stain- treatment of CSF and plasma specimens and ing. Special stainings and immunochemical visualisation of amplified products was done as techniques were used for the diagnosis of described.11 PCR examinations were done opportunistic diseases and HIV encephalitis, as PCR, clinical, and histopathological findings in HIV infected patients whose CSF was positive for HHV-6 DNA DNA PCR findings http://jnnp.bmj.com/ CSF HHV-6 CSF Plasma HHV-6 Plasma Antiherpes treatment CNS HHV-6 Patient Sample (days)* (variant) CMV (variant) CMV (days) CNS disease (diagnostic procedure) DNA PCR 1 a (−210) NA NA + (A) + Ganciclovir CMV meningoencephalomyeloradiculitis − b 0 + (A) + NA NA (from−170 to+30) HIV encephalopathy c (+5) + (A) + + (A) + (clinical+necropsy) d (+14) + (A) + NA NA e (+30) + (A) + − + 2 a 0 + (ND) + + (B) + Ganciclovir Toxoplasmosis, CMV encephalitis‡ + (ND)§ b (+12) + (ND) − + (B) + (from+40 to+55) (clinical+necropsy) on September 24, 2021 by guest. Protected c (+28) + (B) + − + d (+55) + (B) − − + 3 a 0 + (B) − − − None Toxoplasmosis NA b (+182) + (B) − NA NA (clinical) c (+421) + (B) − + (B) + 4 a† 0 + (B) + + (B) + Ganciclovir CMV meningoencephalitis NA b (+5) NA NA + (B) + (from−2 to+18) (clinical) c (+24) + (B) − NA − 5 a 0 + (A) − + (A) + Ganciclovir Toxoplasmosis NA (from−50 to−10) (clinical) 6 a (−98) − − NA NA None Toxoplasmosis (clinical+necropsy) − b 0 + (B) − NA NA PML (necropsy) 7 a 0 + (ND) + − + Ganciclovir CMV encephalitis NA b (+100) − + − + (from−180 to+80) (clinical) 8 a† 0 + (ND) + − + None Primary lymphoma (biopsy) − CMV encephalitis (clinical) NA=sample not available; ND=HHV-6 variant not defined; +=positive, −=negative. *In parentheses: number of days before (−) or after (+) CSF sampling in concomitance to onset of neurological disease (0). †Varicella zoster virus (patient 4) or Epstein-Barr virus (patient 8) was also found in the CSF. ‡CMV was demonstrated in the same periventricular areas that were found to be HHV6 positive by PCR. §HHV-6 DNA was found in 5 of 13 sections, including cerebral cortex, basal ganglia, and periventricular areas; no additional material was available for examination by the subtype PCR. Human herpesvirus 6 in cerebrospinal fluid of HIV infected patients 791 J Neurol Neurosurg Psychiatry: first published as 10.1136/jnnp.67.6.789 on 1 December 1999. Downloaded from described.11 Brain tissue samples from the portion of controls, suggesting that diVerent patients whose CSF was HHV-6-DNA positive detection rates may depend on the diVerent were also examined by HHV-6 PCR.11 sensitivity limits of the PCR assays, and that passenger HHV-6 positive blood lymphocytes Results may be detected in CSF if a very sensitive assay HHV-6-DNA was found in the CSF of eight of is used. DiVerently from children with primary the 365 patients (2.2%, table). HHV-6 A was infection and patients with multiple sclerosis, found in two patients and HHV-6 B in four; in in whom the variant B of HHV-6 is predomi- the remaining two patients the HHV-6 variant nantly identified,18both variants were found in was not defined, because the subtype PCR our patient group.