Antiviral IgM and IgG subclasses in varicella zoster associated neurological syndromes

Hypovitaminosis Din Postherpetic Neuralgia-High Prevalence and Inverse Association with Pain: A Retrospective Study

Hypovitaminosis D (25-hydroxyvitamin D (25(OH)D) <75 nmol/L) is associated with neuropathic pain and varicella-zoster virus (VZV) immunity. A two-part retrospective hospital-based study was conducted. Part I (a case-control study): To investigate the prevalence and risk of hypovitaminosis D in postherpetic neuralgia (PHN) patients compared to those in gender/index-month/age-auto matched controls who underwent health examinations. Patients aged ≥50 years were automatically selected by ICD-9 codes for shingle/PHN. Charts were reviewed. Part II (a cross-sectional study): To determine associations between 25(OH)D, VZV IgG/M, pain and items in the DN4 questionnaire at the first pain clinic visit of patients. Independent predictors of PHN were presented as adjusted odds ratios(AOR) and 95% confidence intervals (CI). Prevalence (73.9%) of hypovitaminosis D in 88 patients was high. In conditional logistic regressions, independent predictors for PHN were hypovitaminosis D (AOR3.12, 95% CI1.73–5.61), malignancy (AOR3.21, 95% CI 1.38–7.48) and Helicobacter pylori-related peptic ulcer disease (AOR3.47, 95% CI 1.71–7.03). 25(OH)D was inversely correlated to spontaneous/brush-evoked pain. Spontaneous pain was positively correlated to VZV IgM. Based on the receiver operator characteristic curve, cutoffs for 25(OH)D to predict spontaneous and brush-evoked pain were 67.0 and 169.0 nmol/L, respectively. A prospective, longitudinal study is needed to elucidate the findings.

Diagnostic Testing of Neurologic Infections

Neuroinfectious diseases continue to cause morbidity and mortality worldwide, with many emerging or reemerging infections resulting in neurologic sequelae. Careful clinical evaluation coupled with appropriate laboratory investigations still forms the bedrock for making the correct etiologic diagnosis and implementing appropriate management. The treating physician needs to understand the individual test characteristics of each of the many conventional candidate-based diagnostics: culture, pathogen-specific polymerase chain reaction, antigen, antibody tests, used to diagnose the whole array of neuroinvasive infections. In addition, there is a growing need for more comprehensive, agnostic testing modalities that can identify a diversity of infections with a single assay.

Serological diagnosis of varicella-zoster virus in sera with antibody-capture enzyme-linked immunosorbent assay of IgM

Evaluation was made of three enzyme-linked immunosorbent assay (ELISA) formats; varicella-zoster virus (VZV) indirect ELISA; VZV IgM capture using biotin and VZV IgM capture using peroxidase, for the detection of VZV-specific IgM antibodies in human sera. It was observed that there was no significant difference in sensitivity of detection using the three formats but there were important practical differences in the number of steps and hence time for assay completion between the three assay formats. All assays showed some cross-reactivity with sera containing anti-HSV1 antibodies.

Similar humoral and cellular immunological reactivities to human herpesvirus 6 in patients with multiple sclerosis and controls

Several studies have suggested an association between human herpesvirus 6 (HHV-6) and multiple sclerosis (MS). We have previously studied intrathecal production of antibody to lymphotropic herpesviruses in MS patients and the presence of human herpesvirus 1 to 7 DNAs in cerebrospinal fluid (CSF). In the present study anti-HHV-6 immunoglobulin M (IgM) in serum and anti-HHV-6 IgG subclasses in serum and CSF were examined and the lymphoproliferative response to HHV-6 was analyzed. The PCR examination was refined by purifying DNA from CSF and retesting the samples for HHV-6 DNA. There were no statistically significant differences between the groups concerning IgM positivity, distribution of IgG subclasses, or lymphoproliferative response to HHV-6. The purification of DNA increased the number of PCR-positive samples from 0 of 71 to 4 of 68. The study does not give additional support to the possibility that HHV-6 is a common cause of MS, but a role for the virus in a subset of patients cannot be excluded.

Specific diagnostic methods for herpesvirus infections of the central nervous system: a consensus review by the European Union Concerted Action on Virus Meningitis and Encephalitis

BACKGROUND

Herpesvirus infections of the central nervous system are often severe but are fortunately rare. The incidence of these infections has however, increased in recent years as a consequence of an increase in the number of immune-compromised individuals. New diagnostic procedures have improved our ability to diagnose these infections and herpesviruses may yet be implicated as the cause of further neurological diseases with no known aetiology. Methodological standards for selection and evaluation of patient materials are essential to the provision of reliable diagnosis, yet few studies have addressed this important issue.

OBJECTIVES

To describe and define methodological standards and reference methodology for diagnosis of herpesvirus infections of the CNS.

STUDY DESIGN

Information gathered by literature review.

RESULTS

Only for herpes simplex encephalitis is there sufficient data to allow the definition of reference methodology. Good methodological standards exist but few studies have adhered to these standards. As methods for the detection of specific intrathecal antibody synthesis are well established yet under-used in diagnostic virology, the principle of these measurements is reviewed in some detail.

CONCLUSIONS

Herpesvirus infections of the CNS are of increasing importance. High quality, multi-centre studies are needed to establish the value of the new diagnostic test procedures if further improvement in the diagnostic sensitivity and specificity of these procedures is to be achieved.

Detection of both herpes simplex and varicella-zoster viruses in cerebrospinal fluid from patients with encephalitis

Cerebrospinal fluid (CSF) samples from 46 patients with encephalitis were studied for the presence of herpes simplex virus (HSV) types 1 and 2 and/or varicella zoster virus (VZV)-specific DNA sequences by the polymerase chain reaction (PCR) assay. Patients were studied because of detection of intrathecal production of IgG antibody to HSV alone (10 patients, Group A) or to both HSV and VZV (11 patients, Group B) or because of the presence of specific anti-HSV IgG in CSF without evidence of intrathecal antibody production (25 patients, Group C). CSF samples taken between days 1 and 10 from onset of encephalitis were available from all patients, and follow-up samples (taken after 10 days from onset) were obtained from some of them. Positive PCR results were obtained in a total of 13 patients. Four patients (three from Group A and one from Group B) gave amplification of HSV type 1 DNA alone, two patients (both from Group B) showed amplification of VZV DNA alone, and seven patients (all from Group B) gave dual amplification of both HSV type 1 and VZV DNA sequences in CSF. All CSF samples from patients in Group C were negative by PCR. Ten patients with CSF samples positive by PCR lacked a prior history of herpetic cutaneous lesions. In seven patients, serum antibody tests (specific IgM detection and specific IgG avidity assays) identified both primary and recurrent infections. The results suggest that the dual presence of IgG antibody to both HSV and VZV in CSF from patients with encephalitis may reflect in some cases a dual infection of the central nervous system caused by both agents.

Affinity of antigen-specific IgG distinguishes multiple sclerosis from encephalitis

The characteristics of antigen-specific IgG in patients with multiple sclerosis and patients with encephalitis have been compared. Both groups of patients showed antigen-specific oligoclonal bands locally synthesised in the CSF. When the affinity distribution of the antigen-specific IgG was measured there was a marked difference between the two groups. Encephalitis patients had high affinity antibody against the causative antigen. This was consistent with the antibody undergoing affinity maturation as a result of the immune system fighting a primary infection. Multiple sclerosis patients lacked high affinity response. This lack of high affinity antibody was also seen in those encephalitis patients when antigens other than the causative antigen were studied.

Detection of varicella-zoster virus-specific DNA sequences in cerebrospinal fluid from patients with acute aseptic meningitis and no cutaneous lesions

Acute aseptic meningitis (AAM) is considered as an uncommon manifestation of varicella-zoster virus (VZV) recrudescence and is usually regarded as a complication of the cutaneous infection in patients with impaired cellular immunity. Indirect evidence suggests, however, that VZV-associated AAM may also respond to direct spread of the virus to the leptomeninges from the cells supporting the latency. The polymerase chain reaction (PCR) was used to amplify VZV-specific DNA sequences in serial cerebrospinal fluid (CSF) samples from 21 patients with AAM, who presented laboratory evidence of intrathecal production of VZV-specific antibody on follow-up. Eleven of these patients never showed cutaneous zosteriform lesions. VZV-DNA sequences were detected in the CSF from all patients with cutaneous zoster, as well as from six patients (55%) lacking skin lesions. Viral DNA sequences were present in six cases before the rise in specific antibody was seen in CSF, disappearing during follow-up in the seven positive cases. These results support the proposed involvement of VZV in the etiology of AAM seen among normal young adults and strongly suggest that the virus can reach directly and infect the CNS from the latently infected spinal ganglia.

HIV-1 specificity of cerebrospinal fluid and serum IgG, IgM, and IgG1-G4 antibodies in relation to clinical disease

The reactivities of intrathecal and serum IgG and IgM, and IgG1-4 subclass antibodies to various HIV-1 proteins were assessed by immunoblotting at various stages of HIV-1 infection. All patients were examined neurologically including CT and/or MRI, and with HIV-1-specific and nonspecific tests of the cerebrospinal fluid (CSF). In early infection, the occurrence of anti-gag antibodies in both CSF and serum was higher than that of anti-pol antibodies among all IgG subclasses (P < 0.05). Also in late infection, anti-gag IgG1 response was most frequent (P < 0.04), while anti-gag IgG3 and IgG4 reactivities predominated over similar anti-pol antibodies (P < 0.05, respectively). Of anti-pol reactivities, in the CSF of subjects at early infection anti-p32 IgG and IgG1 antibodies were more frequent than in patients at late stages (P < 0.015). In late infection, however, the occurrence of anti-p64 IgM and IgG2-4 antibodies of both CSF and serum was higher than at early stages (P = 0.014). Regarding anti-env response, in patients with advanced infection, the CSF and serum IgG subclass reactivity against gp120 was restricted to IgG1. The CSF of individual patients with HIV encephalopathy showed a higher or similar occurrence of polyisotypic anti-gag and anti-pol IgG3 antibodies than corresponding serum. These results indicate association between declining frequency of anti-pol p32 and anti-env gp120 antibodies and severity of HIV-1 disease.(ABSTRACT TRUNCATED AT 250 WORDS)

The diagnostic significance of antibody specificity indices in multiple sclerosis and herpes virus induced diseases of the nervous system

The antibody specificity index (ASI) indicates the cerebrospinal fluid (CSF)/serum difference of antibody amounts per weight unit IgG (normal less than 1.5). It has proven to be the most sensitive inflammation parameter in CSF analysis so far, more sensitive than the Western blot, the "oligoclonal" response, and the empirical differentiation of CSF immunoglobulins. By this diagnostic criterion, several benign viral meningitis cases were found to be caused by the varicella/zoster virus. The diagnostic relevance of local zoster antibody synthesis was greatest in ganglionitis cases, e.g., in zoster oticus sine herpete (facial paresis) and acute radicular syndromes of the elderly. The diagnostic significance of the local immune response against measles, rubella, and zoster antigens (MRZ response) was ascertained further. Together with oligoclonal gamma-globulin fractionation, there is now only 1 out of 100 multiple sclerosis (MS) patients left who has been found to have a normal CSF.

Herpes zoster associated encephalitis in dialysis patients

Two patients on dialysis because of chronic renal failure who developed herpes zoster associated encephalitis are reported. Both developed overt encephalopathy despite treatment with oral acyclovir for the preceding herpes zoster eruption. The encephalopathy responded rapidly to intravenous acyclovir.

Intrathecal antibody production against viruses of the herpesvirus family in acute retinal necrosis syndrome

Viruses of the herpesvirus family cause acute retinal necrosis syndrome, a devastating necrotic retinitis in immunocompetent individuals. Direct proof of the viral origin of this disease may be obtained by demonstration of the virus, viral antigens, or viral DNA in biopsy specimens of retinas. In search of alternative diagnostic methods, we analyzed cerebrospinal fluid and serum with enzyme-linked immunosorbent assays for virus-specific antibody activity. Intrathecally produced viral antibodies were found in three consecutive patients with acute retinal necrosis syndrome: herpes simplex type 2 in a 30-year-old woman with a history of suspected neonatal herpes encephalitis, herpes simplex type 1 in a 35-year-old man, and varicella-zoster virus activity in a 62-year-old woman. None of the patients had clinical signs indicating an acute disorder in the central nervous system. This serologic approach seems to be of value for the diagnosis of an associated intracerebral viral infection in cases of acute retinal necrosis syndrome.

Active production of anti-human T-lymphotropic virus type I (HTLV-I) IgM antibody in HTLV-I-associated myelopathy

We investigated the presence of anti-human T-lymphotropic virus type I (HTLV-I) IgM in sera and cerebrospinal fluid from patients with HTLV-I-associated myelopathy (HAM) by Western blot analysis. Analyses of 36 serum samples revealed that most patients (31/36; 86.1%) had anti-HTLV-I IgM, whereas only four of 23 (17.4%) HTLV-I carriers had it. In studies of cerebrospinal fluid, anti-HTLV-I IgM was detected in 24 of 36 (66.7%) HAM patients, whereas none was detected in nine HTLV-I carriers. The differences were statistically significant (p less than 0.01). These results suggest that persistent active replication of HTLV-I occurs in the central nervous system as well as in the peripheral blood of HAM patients, and may contribute to the development of HAM.

Fine analysis of intrathecally synthesized anti-HIV IgG1-4 by peptide mapping

ELISAs utilizing HIV-derived synthetic peptides as antigen were used to analyze serum and CSF IgG1-4 from 15 HIV infected patients. Intrathecally synthesized IgG1-4 reactive to one or several HIV-derived peptides were detectable in 12 of 15 patients. Intrathecally synthesized anti-peptide IgG was more common in patients with neurological symptoms than in those without. CSF reactivity not paralleled by serum reactivity was detected to HIV-peptides in 4 patients. IgG1-4 to gp41 was relatively more frequent in the CNS than IgG1-4 to gag. Intrathecal IgG synthesis to the gp120 peptide was not detected in any patient. The anti-peptide responses were dominated by IgG1. Intrathecal IgG2 and 4 synthesis was found in 2 and 5 patients, respectively. IgG3 synthesis intrathecally was not detected in any of the patients. ELISAs detecting IgG1-4 to HIV-derived synthetic peptides are feasible to analyze the fine specificities of intrathecal IgG. The mapping of idiotypes and isotypes of IgG synthesized in the CNS will increase the possibilities of elucidating B-cell regulation in the CNS and which viral components evoke immune responses.

Specific in vitro IgG subclass synthesis and lymphocyte proliferation responses in herpes virus encephalitis

Cerebrospinal fluid, peripheral blood lymphocytes (PBL) and sera from 5 patients with herpes simplex encephalitis (HSVE), 3 with varicellae zoster (VZV) meningoencephalitis and 5 with encephalitis of unknown origin (NUD) were analyzed. Lymphocytes from both blood and CSF were shown to synthesize anti-VZV IgG subclasses in VZV meningoencephalitis and anti-HSV IgG subclasses in HSVE. The subclass patterns of CSF and in vitro synthesized anti-viral IgG were similar, suggesting that a considerable portion of the antiviral IgG subclasses detected are synthesized in the CNS compartment. Antigen presentation in vitro seemed to produce a heterologous IgG4 and/or 3 response in 3 patients. Lymphocyte proliferation was detectable in response to HSV and VZV, respectively.