Antibody to Coxsackie B virus in diagnosing postviral fatigue syndrome

OBJECTIVE

To study the association between coxsackie B virus infection and the postviral fatigue syndrome and to assess the immunological abnormalities associated with the syndrome.

DESIGN

Case-control study of patients with the postviral fatigue syndrome referred by local general practitioners over one year.

SETTING

General practitioner referrals in Dunbartonshire, Scotland.

PATIENTS

254 Patients referred with the postviral fatigue syndrome (exhaustion, myalgia, and other symptoms referable to postviral fatigue syndrome of fairly recent onset--that is, several months) and age and sex matched controls obtained from same general practitioner; 11 patients were rejected because of wrong diagnoses, resolution of symptoms, and refusal to participate, leaving 243 patients and matched controls.

MAIN OUTCOME MEASURES

Detailed questionnaire (patients and controls) and clinical examination (patients) and blind analysis of blood sample at entry and after six months for determination of coxsackie B virus IgM and IgG antibodies and other variables (including lymphocyte protein synthesis, lymphocyte subsets, and immune complexes).

RESULTS

Percentage positive rates for coxsackie B virus IgM at entry were 24.4% for patients and 22.6% for controls and for coxsackie B virus IgG 56.2% and 55.3% respectively; there were no significant differences between different categories of patients according to clinical likelihood of the syndrome nor any predictive value in a fourfold rise or fall in the coxsackie B virus IgG titre in patients between entry and review at six months. The rates of positive antibody test results in patients and controls showed a strong seasonal variation. Of the numerous immunological tests performed, only a few detected significant abnormalities; in particular the mean value for immune complex concentration was much higher in 35 patients and 35 controls compared with the normal range and mean value for total IgM was also raised in 227 patients and 35 controls compared with the normal range.

CONCLUSIONS

Serological tests available for detecting coxsackie B virus antibodies do not help diagnose the postviral fatigue syndrome. Percentage positive rates of the antibodies in patients simply reflect the background in the population as probably do the raised concentrations of total IgM and immune complexes.

Paraneoplastic limbic encephalitis: clinico-pathological correlations

Three new cases of limbic encephalitis in association with malignancy are reported. The literature on this condition is reviewed and the clinical, laboratory and histopathological features of cases proven at necropsy are correlated. The possible pathogenic mechanism of this disorder is discussed.

Brain abnormalities in immune defective mice

Mouse strains with or without immune disorders were examined in order to further assess the incidence of brain anomalies in immune-disordered strains. The brain was examined in Nissl-stained serial sections under a light microscope for the presence of abnormalities, with specific attention to ectopic collections of neurons in layer I of the neocortex, as reported in the autoimmune New Zealand Black (NZB) and BXSB strains. The present study was designed to survey additional strains with immune disorders (Snell dwarf, C57BL/6J-nu/nu, BALB/cByJ-nu/nu, and SJL) and 7 control strains without immune disorders. In addition, we attempted to replicate past findings in the highly affected BXSB strain and the MRL/1 strain, which develops autoimmune disease, but has a low incidence of brain abnormalities. The largest number of brain abnormalities (20-40%) were seen in the C57BL/6J-nu/nu, Snell dwarf and BXSB strains. The anomalies in the C57BL/6J-nu/nu and BXSB mice consisted of ectopic neurons in layer I of the neocortex, whereas the Snell dwarf mice had either neuron-free areas in the cortex, or rippling of cortical layers II-IV, and one case had agenesis of the corpus callosum. Between 4% and 8% of the mice from the SJL, MRL/1, and MRL +/+ strains had either neuron-free areas in the cortex or ectopic neurons in layer I. The BALB/cByJ-nu/nu and control strains did not have any cortical abnormalities. Future studies will be designed to determine whether immune-based alterations to the developing brain are responsible for the brain anomalies present in immune-disordered strains.

A correlation between severity of migraine and delayed gastric emptying measured by an epigastric impedance method

1. This study examined the ability of a bioimpedance method to detect the delay in gastric emptying which occurs during attacks of migraine. 2. In 64 non-migraineur control patients and 46 migraine patients outside an attack, gastric emptying rates were within the predicted normal range. 3. In contrast, rates in 14 migraineurs during 20 attacks were delayed during severe or moderate attacks and were significantly correlated with the intensity of headache, nausea and photophobia. 4. The epigastric impedance method was generally well tolerated by patients and appears to merit further investigation as a clinical method of monitoring gastric emptying of liquids.

Effect of high doses of essential fatty acids on the postviral fatigue syndrome

Sixty-three adults with the diagnosis of the postviral fatigue syndrome were enrolled in a double-blind, placebo-controlled study of essential fatty acid therapy. The patients had been ill for from one to three years after an apparently viral infection, suffering from severe fatigue, myalgia and a variety of psychiatric symptoms. The preparation given contained linoleic, gamma-linolenic, eicosapentaenoic and docosahexaenoic acids and either it, or the placebo, was given as 8 x 500 mg capsules per day over a 3-month period. The trial was parallel in design and patients were evaluated at entry, one month and three months. In consultation with the patient the doctors assessed overall condition, fatigue, myalgia, dizziness, poor concentration and depression on a 3-point scale. The essential fatty acid composition of their red cell membrane phospholipids was analysed at the first and last visits. At 1 month, 74% of patients on active treatment and 23% of those on placebo assessed themselves as improved over the baseline, with the improvement being much greater in the former. At 3 months the corresponding figures were 85% and 17% (p less than 0.0001) since the placebo group had reverted towards the baseline state while those in the active group showed continued improvement. The essential fatty acid levels were abnormal at the baseline and corrected by active treatment. There were no adverse events. We conclude that essential fatty acids provide a rational, safe and effective treatment for patients with the post-viral fatigue syndrome.

Immunological abnormalities in BXSB mice at the onset of SLE development

Male BXSB mice develop murine lupus spontaneously at about 3 months of age. Polyclonal B-cell activation is thought to play a major role in the development of the syndrome in these mice, but the immunological events which lead to this activation are not known. We therefore examined the immune characteristics of mice aged 10-16 weeks, at the onset of disease. We found several immunological markers, indicating polyclonal B-cell activation leading to early, preclinical, disease activity in both male and female BXSB mice, but consistent abnormalities in the percentages and function of lymphocyte subpopulations were found only in male BXSB mice. In particular, the ratio of helper to suppressor/cytotoxic T cells was found to be significantly lower in male BXSB, than in either females of this strain, or normal control DBA2 mice. We conclude that defective immunoregulation is likely to be significant in the initiation of murine lupus, since it is detectable at the onset of disease in male BXSB mice.

Assay of complement activation in mouse serum by ELISA

We describe a simple, sensitive and reproducible ELISA assay for complement activation in mouse serum, based on measurement of the opsonization of purified, heat-aggregated mouse gamma-globulin bound to the solid phase. This assay measures mainly classical pathway activation, and we used it to show significant differences in complement activation in sera from mice of various autoimmune, immunodeficient and immunologically normal strains. This assay has the advantage over existing methods of requiring minimal volumes of serum, and of avoiding problems of species incompatibility.

Localised Wegener's granulomatosis--a difficult and delayed diagnosis. Clinical report and literature review

A case of localised Wegener's granulomatosis presenting with central nervous system symptoms and signs is described. The difficulties of early diagnosis are high-lighted and the diagnostic criteria of the disease are discussed.

A search for common immunological abnormalities at the onset of murine lupus in two genetically different strains

Mice of the genetically different BXSB and MRL/lpr strains develop murine lupus spontaneously at about three months of age. Polyclonal B-cell activation is thought to play a major role in the development of the syndrome in each strains, but the immunological events which lead to this activation are not known. We therefore examined the immune characteristics of mice aged 10-16 weeks, at the onset of the disease. We found consistent abnormalities in the percentages of lymphocyte sub-populations in both male BXSB, and male and female MRL/lpr mice. In particular, the ratio of helper to suppressor/cytotoxic T cells was found to be significantly lower in male BXSB, and in male and female MRL/lpr mice than in normal, control, DBA2 mice. Significant increases in serum IgG and IgA concentrations, indicative of polyclonal B cell activation, were present in each strain. The histological appearance of the lymphoid organs and the functional responses to mitogen stimulation were, however, distinctly different. We conclude that defective immunoregulation is likely to be significant in the initiation of murine lupus, since it is detectable at the onset of disease in two genetically distinct strains. It may be associated, however, with different immunological phenomena in strains of different genetic backgrounds.

Family studies of congenital heart block associated with Ro antibody

Complete congenital heart block is associated with the presence of maternal autoantibodies to small ribosomal nucleoproteins (such as anti-Ro) which cross the placenta and may be deposited at the site of cardiac damage. Ten such cases of congenital heart block, their mothers, and their siblings were studied. The seropositive mother of one case had a similar conduction defect (bifascicular block) to that in her affected child. None of the siblings examined had cardiac lesions. Six mothers had Ro or La antibody five to 17 years after the birth of the affected child. Four mothers examined 11-32 years after the birth of an affected child were seronegative. Three of these mothers had evidence of a connective tissue disorder. This evidence is consistent with a hypothesis that a maternal viral infection, associated with autoantibody production, leads to virus crossing the placenta, damaging the fetal heart, and eliciting local deposition of maternal antibody.

Postviral fatigue syndrome: persistence of enterovirus RNA in muscle and elevated creatine kinase

Enterovirus-specific probes have been prepared by reverse transcription of conserved sequences in purified Coxsackie B2 virus genomic RNA and molecular cloning techniques. These probes were used in quantitative slot blot hybridizations to test for the presence of enterovirus-specific RNA in skeletal muscle biopsy specimens from 96 patients who had suffered from the postviral fatigue syndrome myalgic encephalomyelitis for up to 20 years. Biopsy specimens from 20 patients were positive for the presence of virus-specific RNA with hybridization signals more than three standard deviations greater than the mean of the normal muscle controls. Biopsies from the remaining 76 patients were indistinguishable from the controls. These data show that enterovirus RNA is present in skeletal muscle of some patients with postviral fatigue syndrome up to 20 years after onset of disease and suggest that a persistent virus infection has an aetiological role.

The inflammatory process in polymyositis: monoclonal antibody analysis of muscle and peripheral blood immunoregulatory lymphocytes

An analysis was made of the lymphocyte subpopulations in the muscle lesions and the peripheral blood of 25 patients with inflammatory myopathy, in the acute or chronic phase of the disease. Percentages of activated T lymphocytes (65% +/- 3.4), both helper and suppressor/cytotoxic, macrophages (25% +/- 3.2) and B cells (11% +/- 0.9) in the tissues were similar at all stages of the illness; T cells were, however, more common in acute polymyositis than in acute dermatomyositis, where B cells were significantly increased. A loss of circulating OKT8-positive lymphocytes in the peripheral blood was demonstrated, supporting other evidence of disturbed immunoregulation. It was concluded that the attack on muscle fibres is mediated by T cells, macrophages, and B cells, with the first two playing the major roles.

Nifedipine in the treatment of myotonia in myotonic dystrophy

Abnormal calcium transport may be implicated in the membrane defect in myotonic dystrophy. A single blind crossover trial of placebo (t.i.d.), nifedipine 10 mg (t.i.d.) and nifedipine 20 mg (t.i.d.), was performed in 10 patients with myotonic dystrophy. The severity of myotonia was assessed by measuring finger extension time after maximum voluntary finger flexion. A significant improvement in myotonia, after nifedipine, was recorded by this technique and supported by a subjective improvement in 50% of patients and clinical improvement of greater than 20% in five patients. Initial grip strength and muscle fatiguability measured by grip strength ergometry were not significantly altered.

Cardiac damage in polymyositis associated with antibodies to tissue ribonucleoproteins

Cardiac damage, consisting of mild diffuse myocarditis or severe inflammation and fibrosis of the conduction system or both, occurs in more than 70% of patients with idiopathic polymyositis. The lesions are strikingly similar to those detected in the infants of mothers with connective tissue diseases. In these infants the damage is associated with the transplacental passage of a maternal antibody to tissue ribonucleoproteins (anti-Ro). The same antibody was identified in 60% of 55 patients with polymyositis and in 69% (23/33) of those with associated cardiac damage including four with complete heart block. Forty five per cent of those patients who were anti-Ro seropositive had no clinical or electrocardiographic evidence of cardiac lesions. They were in the acute phase of illness, however, and no other more detailed heart investigations had been done. It is postulated that cardiac damage in polymyositis is caused by the antibody and that its presence may serve as a marker for heart involvement.

Experimental autoimmune thyroiditis: attempt to correlate disease development with lymphocyte subset changes

An attempt was made to correlate lymphocyte subset abnormalities with the development of experimental autoimmune thyroiditis (EAIT) in thymectomized and irradiated rats of five inbred strains. The peripheral blood subpopulations were analysed using the fluorescence-activated cell sorter (FACS-IV). A significant lymphopenia with a severe decrease in helper T cells was identified in all the treated rats. In addition, a significant loss of suppressor cytotoxic T cells was found in rats of the most susceptible strain (August) and in the majority of affected individual rats of the other strains. The simple, modified protocol which we used revealed differences in strain susceptibility to EAIT, with 66% of August rats having histological evidence of disease, 50% of Lewis, 44% of Agus, 30% of Hooded Lister and 20% of Wistar, at 5 to 8 months after treatment. Levels of antithyroglobulin antibody, estimated by an ELISA assay, correlated well with the histological results. In all groups, three times as many females as males were affected. Our findings support the view that genetic and immunoregulatory factors are involved in the development of EAIT, with loss of both helper and suppressor cells playing an important role.

Biopterin in Parkinson's disease

Tetrahydrobiopterin is an essential co-factor in the natural synthesis of dopamine. Oral tetrahydrobiopterin was given in small doses to four patients with early Parkinson's disease but had no discernible effect.

Neuroanatomical anomalies in autoimmune mice

The cerebral cortex was examined for signs of pathology in the NZB, BXSB, and MRL autoimmune strains of mice, crosses among these strains, and control mice. Previously, we reported that 20% of NZB mice had ectopic collections of neurons in layer I of the cortex. In this study we replicated this finding in the NZB, and extended it to the BXSB strain, and BXSB/NZB and MRL/NZB hybrids. The MRL strain, however, did not have a large number of individuals with brain anomalies. Thus, a number of autoimmune mice strains and hybrids develop brain anomalies, although at least one autoimmune strain does not. We suggest that in certain autoimmune strains maternal autoantibodies cross the placenta and damage the developing fetal brain, and that these strains may be useful experimental models for studying the development of brain anomalies seen in the dyslexic human.

A new model for multiple sclerosis: chronic experimental allergic encephalomyelitis induced by immunization with cerebral endothelial cell membrane

Multiple sclerosis is considered to be an autoimmune demyelinating disease of the central nervous system. Damage to the blood-brain barrier, of which endothelial cells are the main constituent, occurs in multiple sclerosis, probably due to immunological mechanisms. We report here the results of immune-mediated damage to these cells, produced by immunizing guinea pigs with an endothelial cell membrane fraction. The fraction was obtained from cerebral endothelial cells grown in vitro and was free from myelin basic protein. The immunized animals developed a chronic neurological illness with evidence of delayed hypersensitivity to the cell membrane fraction but not to myelin antigens. Histological examination of the brain in the acute stage showed mononuclear cell infiltrates around blood vessels, while in the chronic phase large areas of demyelination, especially in the periventricular region, were present. This bore a striking similarity to the brain in multiple sclerosis. This may prove to be a useful new animal model for the investigation of the human demyelinating disease.

Lymphocyte subset abnormalities in patients with spasmodic torticollis

The aetiology of spasmodic torticollis is unknown but the patients form a heterogeneous group among which are cases apparently precipitated by a viral illness and others associated with autoimmune disease. We therefore decided to investigate the immunoregulatory lymphocyte subsets in our 11 cases. A significant decrease of both helper and suppressor lymphocytes was identified in the group, together with in vitro evidence of depressed suppressor cell function. Disturbance of the immune response may play a role in this puzzling disorder.

Pathogenesis of heart block in a fatal case of dermatomyositis

Approximately 70% of patients with dermatomyositis have evidence of cardiac damage; in one third of cases this affects principally or solely the conduction tissue. In infants similar histological lesions have been associated with a maternal autoantibody, anti-Ro, that crosses the placenta and produces congenital heart block. Anti-Ro antibody was detected in a fatal case of dermatomyositis with lesions of the conduction system.