Biomedical subjects

L Lindquist

Publications and source records attributed to L Lindquist.

At least 19 recordsLinked to original sources

PubMed2000

A new DIG-PCR-EIA method for the detection of Chlamydia pneumoniae DNA in clinical samples.

Chlamydia pneumoniae, a common respiratory pathogen, may also play a role in the pathogenesis of other chronic conditions. For accurate detection of infected persons and verification of results obtained by other PCR methods, a DIG-PCR-EIA method was evaluated. In the DIG-PCR-EIA, a 437 bp DNA sequence was amplified and hybridized with a newly synthesized 229 bp biotin-labeled probe. The end product was detected by an enzyme immunoassay. The sensitivity of DIG-PCR-EIA was compared with Southern blot hybridization and one-step HR/HL PCR, which was the routine method used. DNA was detected to the level of 20 elementary bodies of DIG-EIA-PCR compared to less than 2 by Southern blot, and 200 by HR/HL PCR. Thus a 100-fold increase in sensitivity could be expected by DIG-EIA-PCR compared to the routine method. Throat swabs and adenoid tissue from 22 children with otitis and middle ear secretions from 29 children, as well as throat swabs from 179 blood donors, were analyzed with DIG-EIA-PCR, HL/HR PCR and nested touchdown PCR. 32% of the ear secretions were positive by DIG-EIA-PCR as compared to 5% by the other two methods. Three adenoid tissue samples were positive by all methods applied. Among the child and adult throat samples, 18% and 32%, respectively, were positive by DIG-EIA-PCR and 5% and 10% by HR/HLPCR. The results indicate the suitability of DIG-PCR-EIA for verification of results of HR/HL PCR. DIG-PCR-EIA has a potential for increased sensitivity and adaptation for automation. It should be further evaluated using various types of tissue specimens and DNA extraction methods.

Adenoids↗

PubMed2000

Suppression of macrophage activation with CNI-1493 increases survival in infant rats with systemic Haemophilus influenzae infection.

CNI-1493, a potent macrophage deactivator, was used to treat infant rats systemically infected with Haemophilus influenzae type b (Hib). CNI-1493 was injected 1 h prior to bacterial inoculation and 24 h later and resulted in a 75 percent increased rate of survival compared to that for untreated controls. The effect of CNI-1493 on the inflammatory response was studied by immunohistochemical detection of individual tumor necrosis factor alpha (TNF-alpha)-, interleukin 1 beta (IL-1beta)-, and gamma interferon (IFN-gamma)-producing cells in the spleen. A significant reduction of the incidence of TNF-alpha- and IL-1beta-expressing cells was found for CNI-1493-treated animals. IFN-gamma expression was not suppressed by CNI-1493, indicating that cytokine inhibition was specific in macrophages. CNI-1493 significantly reduced the number of infiltrating granulocytes in the brain from that for controls. This study provides evidence that CNI-1493 protects against lethal Hib infection by deactivating the inflammatory cascade in infant rats.

Animals↗

PubMed1999

[Enterovirus diagnosis is important, but should be used cautiously].

While the enterovirus diagnostic test positive rate is very low in Sweden, many enterovirus diagnoses are probably missed, owing to inappropriate testing, in patients with acute aseptic meningitis. In the article it is recommended that the cerebrospinal fluid PCR (polymerase chain reaction) test should be performed routinely in cases of acute aseptic meningitis. Serology and virus isolation in stool are indicated in cases of acute pericarditis or myocarditis, or certain chronic heart diseases. The PCR test should be performed in serum in the few cases of sepsis-like diseases in newborns or patients with hypogammaglobulinaemia. Otherwise, enterovirus diagnosis is very seldom justified on clinical grounds. For the purpose of poliovirus surveillance, enterovirus isolation may be important for virus typing, especially in cases of paralytic conditions.

Communicable Disease Control↗

PubMed1999

A novel mechanism for cytokine regulation: screening, selection, and characterization of anticytokine monoclonal and polyclonal autoantibodies.

We have recently described an immunoregulatory mechanism involving release of neutralizing autoantibodies (Aab) to cytokines during bacterial infections. Intraperitoneal inoculation of Haemophilus influenzae type b (Hib) into Sprague-Dawley rats resulted in high levels of inflammatory mediators early after infection. Increased titers of cytokine Aab were observed, with a peak at day 7. We cloned Aab-producing B cells. Screening of the clones with five different cytokines resulted in detection of Aab-producing clones reactive with each cytokine. After repeated subcloning, monoclonal Aab (mAab) were selected and characterized for their specificity, isotypes, and affinities. To elucidate regulatory importance, mAab to interferon-gamma (IFN-gamma) and tumor necrosis factor-alpha (TNF-alpha) dose-dependently inhibited IFN-gamma-induced MHC expression by peritoneal macrophages and TNF-alpha-induced thymocyte proliferation, respectively. Fab fragments exhibited binding and neutralizing effects, confirming specificities. Cross-reactivity with other rat cytokines was excluded. Pools of clones containing several mAab to each cytokine were obtained and served as polyclonal Aab. The relative affinity of the Aab was determined and found to be of high index. The characterized Aab were tested in methodologic assays for cytokine detection, revealing that some Aab were useful in a cell release capturing (CRC) ELISA.

Animals↗

PubMed1999

Effects of polysaccharide fucoidin on cerebrospinal fluid interleukin-1 and tumor necrosis factor alpha in pneumococcal meningitis in the rabbit.

The inflammatory response in bacterial meningitis is mediated by cytokines, such as tumor necrosis factor alpha (TNF-alpha) and interleukin-1 (IL-1), which are produced in the subarachnoid space by different cells, e.g., leukocytes, astrocytes, and microglia. The recruitment of leukocytes into the cerebrospinal fluid (CSF) has been shown to contribute to the neurological damage in this disease, a process which could be enhanced by treatment with antibiotics. In this study, we have used a rabbit meningitis model for two sets of experiments with intracisternal (i.c.) injections of Streptococcus pneumoniae. First, pneumococcal cell wall (PCW) components were injected i.c., inducing an inflammatory response with pleocytosis and increased levels of CSF TNF-alpha) and IL-1 at 6 and 12 h after PCW injection. Treatment with fucoidin, known to inhibit leukocyte rolling, abolished pleocytosis and inhibited the release of TNF-alpha and IL-1. In the second experiment, live pneumococcal bacteria were injected i.c. and treatment with one dose of ampicillin (40 mg/kg of body weight intravenously) was given 16 h after induction of meningitis, causing a sevenfold increase in CSF leukocytes over a 4-h period. CSF IL-1 levels at 16 h were high but did not increase further at 20 h. Also, CSF TNF-alpha levels were high at 16 h and tended to increase at 20 h. Fucoidin treatment prevented the antibiotic-induced increase of CSF leukocytes but had no effect on the TNF-alpha and IL-1 levels. Taken together, fucoidin reduced CSF TNF-alpha and IL-1 levels in acute bacterial meningitis induced by PCW fragments but had no effect later in the course of the disease, when live bacteria were used and an inflammatory increase was caused by a dose of antibiotics.

Ampicillin↗

PubMed1999

Neutralization of macrophage inflammatory protein 2 (MIP-2) and MIP-1alpha attenuates neutrophil recruitment in the central nervous system during experimental bacterial meningitis.

Chemokines are low-molecular-weight chemotactic cytokines that have been shown to play a central role in the perivascular transmigration and accumulation of specific subsets of leukocytes at sites of tissue damage. Using in situ hybridization (ISH), we investigated the mRNA induction of macrophage inflammatory protein 2 (MIP-2), MIP-1alpha, monocyte chemoattractant protein 1 (MCP-1), and RANTES. Challenge of infant rats' brains with Haemophilus influenzae type b intraperitoneally resulted in the time-dependent expression of MIP-2, MIP-1alpha, MCP-1, and RANTES, which was maximal 24 to 48 h postinoculation. Immunohistochemistry showed significant increases in neutrophils and macrophages infiltrating the meninges, the ventricular system, and the periventricular area. The kinetics of MIP-2, MIP-1alpha, MCP-1, and RANTES mRNA expression paralleled those of the recruitment of inflammatory cells and disease severity. Administration of anti-MIP-2 or anti-MIP-1alpha antibodies (Abs) resulted in significant reduction of neutrophils. Administration of anti-MCP-1 Abs significantly decreased macrophage infiltration. Combined studies of ISH and immunohistochemistry showed that MIP-2- and MIP-1alpha-positive cells were neutrophils and macrophages. MCP-1-positive cells were neutrophils, macrophages, and astrocytes. Expression of RANTES was localized predominantly to resident astrocytes and microglia. The present study indicates that blocking of MIP-2 or MIP-1alpha bioactivity in vivo results in decreased neutrophil influx. These data are also the first demonstration that the C-C chemokine MIP-1alpha is involved in neutrophil recruitment in vivo.

Animals↗

PubMed1999

Levels of gamma interferon and interleukin-4 are inversely related to the levels of their corresponding autoantibodies in patients with lower respiratory tract infection.

To study the involvement of cytokines and their corresponding autoantibodies (Aabs) in inflammatory mechanisms in patients with lower respiratory tract infections, blood samples were taken from patients at the time of admission to the hospital and before treatment. Cell-released capturing enzyme-linked immunosorbent assay was used to measure the levels of gamma interferon (IFN-gamma) and interleukin-4 (IL-4) produced spontaneously by peripheral mononuclear cells (PMNC). ELISA was used to measure Aabs to these cytokines in sera. The levels of both cytokines were inversely related to the levels of their corresponding Aabs. While a high level of IFN-gamma was observed together with a low level of anti-IFN-gamma Aab, decreased IL-4 levels were observed with increased levels of Aabs to IL-4. Immunoglobulins were purified, digested to obtain Fab fragments, and tested for specificity and cross-reactivity. The Aabs and their Fab fragments were tested in cytokine biological assays and showed neutralizing effects. Our data demonstrated increased levels of the proinflammatory cytokine IFN-gamma and decreased release of the anti-inflammatory cytokine IL-4 during early presentation of lower respiratory tract infection. The levels of these cytokines were inversely related to the levels of their corresponding Aabs that exhibited regulatory effects on the cytokine biological function in vitro.

Adult↗

PubMed1998

Chronic fatigue syndrome differs from fibromyalgia. No evidence for elevated substance P levels in cerebrospinal fluid of patients with chronic fatigue syndrome.

Levels of substance P were determined in the cerebrospinal fluid (CSF) in 15 patients with chronic fatigue syndrome (CFS). All values were within normal range. This is in contrast to fibromyalgia (FM). The majority of patients with FM have increased substance P values in the CSF. The results support the notion that FM and CFS are different disorders in spite of overlapping symptomatology.

Adult↗

PubMed1998

Induction of cytokines and anti-cytokine autoantibodies in cerebrospinal fluid (CSF) during experimental bacterial meningitis.

We have recently described the induction of anti-cytokine autoantibodies (Aabs) in the serum as a novel mechanism for cytokine regulation during bacterial infections. Here we use the infant rat-model of Haemophilus influenzae type b (Hib) meningitis to examine the induction of five potentially important cytokines and their autoantibody responses in the CSF. Protein levels of the cytokines interferon-gamma (IFN-gamma), tumour necrosis factor-alpha (TNF-alpha), transforming growth factor-beta (TGF-beta), IL-4 and IL-10 were detected at day 3 post-inoculation (p.i.) with maximum induction at day 8. Thereafter, these levels of cytokines had become undetectable. Increased Aab titres to these cytokines, except IL-4, were registered with peak levels between days 7 and 9. Upon re-inoculation with Hib at day 30, regeneration of Aabs was recorded 7 days later (i.e. at day 37). To control the specificity of these Aabs, preincubation of the CSF with a cytokine inhibited the binding effects of that particular cytokine, but not those of any other cytokine. Aabs dose-dependently inhibited IFN-gamma-induced MHC expression by peritoneal macrophages and TNF-alpha-mediated L929 cytotoxicity. Our data demonstrate for the first time the existence of the anti-cytokine antibodies in the CSF of the meningitis Hib model. Furthermore, the data present a role for the Aabs in cytokine regulation, which is consistent with the previously demonstrated effects of the Aabs in the serum.

Animals↗

PubMed1998

The polysaccharide fucoidin inhibits the antibiotic-induced inflammatory cascade in experimental pneumococcal meningitis.

There is evidence that the treatment of bacterial meningitis with antibiotics liberates harmful bacterial products in the subarachnoid space (SAS). This enhances meningeal inflammation and in particular the recruitment of leukocytes into the cerebrospinal fluid (CSF), which has been shown to be more harmful than beneficial in this disease. In this study, we used a rabbit meningitis model based on intracisternal injection of live Streptococcus pneumoniae. Ampicillin (40 mg/kg of body weight given intravenously [i.v.] 16 h after induction of meningitis) caused a fivefold increase in CSF leukocytes over a 4-h period. Inhibition of leukocyte rolling by treatment with the polysaccharide fucoidin (10 mg/kg, i.v.) prevented the enhanced leukocyte extravasation into the SAS and attenuated the leakage of plasma proteins over the blood-brain barrier. These results suggest that certain polysaccharides that block leukocyte rolling have the potential to reduce leukocyte-dependent central nervous system damage in bacterial meningitis.

Ampicillin↗

PubMed1998

Regional cerebral blood flow scintigraphy in tick-borne encephalitis and other aseptic meningoencephalitis.

UNLABELLED: In a prospective study, regional cerebral blood flow (rCBF) was studied in patients with aseptic meningoencephalitis at 6 wk and 1 yr after onset of disease. METHODS: Patients with tick-borne encephalitis ([TBE] n = 73) and meningoencephalitis of other etiology ([non-TBE] n = 56) were investigated with rCBF-scintigraphy (SPECT). SPECT images in the acute phase of disease and at long-term follow-up were analyzed for blood-flow disturbances and their localization in the central nervous system and were correlated to clinical course and outcome. RESULTS: Decreased rCBF was seen in 50% of patients after 6 wk (TBE 49%, non-TBE 50%) and in 46% (TBE 47%, non-TBE 46%) after 1 yr. The decrease in rCBF was moderate in 18% and 11% at 6 wk and in 8% and 9% at the 1-yr follow-up of TBE and non-TBE patients, respectively. Reduced rCBF was significantly more common among patients with encephalitis than among those with meningitis, and more common in males. The distribution of cerebral flow changes was predominantly patchy or multifocal. At long-term follow-up, improvement in rCBF was seen in 28 of 109 patients (26%), but worsening of decreased rCBF was demonstrated in 19 of 109 (17%). In TBE patients, remaining neurological symptoms at 6 wk of disease were associated with worsening of decreased rCBF at the 1-yr follow-up. CONCLUSION: With SPECT, rCBF changes, mostly slight and patchy or multifocal, were detected in patients with aseptic meningoencephalitis. Decreased rCBF was more frequent in patients with moderate-to-severe encephalitis, although the clinical use in predicting long-term outcomes in aseptic meningoencephalitis (e.g., TBE) seems limited.

Adolescent↗

PubMed1997

Cytokine mRNA profiles during the course of experimental Haemophilus influenzae bacterial meningitis.

Intraperitoneal inoculation of Haemophilus influenzae type b (Hib) to 3-week-old Sprague-Dawley rats resulted in nonlethal meningitis with high levels of leukocytes in the cerebrospinal fluid (CSF) and positive bacterial culture. Using in situ hybridization, levels of cytokine mRNA-expressing cells were determined in the brain, CSF, and spleen from Hib-inoculated and uninfected control rats. IFN-gamma, IL-1 beta, IL-4, IL-6, IL-10, IL-12, and TNF-alpha mRNA levels were elevated at 12 hr postinoculation (pi) in spleen and CSF. At this time point, strong expression of IL-6 and TGF-beta was detected in the brain, and also of IL-10 at 48 hr while IFN-gamma and IL-12 were expressed at very low levels throughout the observation time. Delayed cytokine induction occurred in CSF compared to spleen and brain. TGF-beta was high in CSF at 48 hr, and some elevation of IL-1 beta, IL-6, IL-10, TNF-alpha, IFN-gamma, and IL-12 was evident at 72 hr pi. This may suggest measures that promote production of TGF-beta and/or IL-10 should be evaluated in treatment of bacterial meningitis.

Animals↗

PubMed1997

Tick-bone encephalitis in Sweden in relation to aseptic meningo-encephalitis of other etiology: a prospective study of clinical course and outcome.

A total of 149 patients with clinical symptoms of acute viral meningo-encephalitis were enrolled in this study from June 1991 to December 1993. Tick-borne encephalitis (TBE) was diagnosed in 85 of the 149 patients (males 54%, median age 42 years (range 15-78)). The initial clinical appearance of TBE was classified as mild (mainly meningeal; (n = 47), moderate (n = 31) or severe (n = 7), more or less encephalitic. The most common acute symptoms of encephalitis were ataxia (26%), altered consciousness (20%), decreased concentration or memory (9%), irritable response to light and sound (28%), tremor (9%) and dysphasia (9%). Spinal nerve paralysis (11%) occurred in all three clinical stages and did not correlate with the severity or duration of encephalitis. The duration of hospitalisation, the time on the sick-list and the time to recovery were significantly longer in TBE patients. All patients survived, but many patients with TBE suffered an extended period of neurological dysfunction. Of patients with TBE 80% (68/85) showed persisting symptoms of CNS dysfunction on follow-up at week 6, compared with 55% (35/64) of the patients with aseptic meningitis of other aetiology. The corresponding figures after 1 year were 40% (33/83) and 20% (13/64). One year after TBE 13 (28%) patients with initially mild, meningeal symptoms had decreased memory and decreased concentration capacity, dysphasia or ataxia. Spinal nerve paralysis persisted after 1 year in 5 of 9 patients with TBE. In conclusion, TBE in Sweden is associated with a significant morbidity and a post-TBE syndrome existed after 1 year in more than one third of the patients.

Adolescent↗

PubMed1997

Intrathecal IgM, IgA and IgG antibody response in tick-borne encephalitis. Long-term follow-up related to clinical course and outcome.

BACKGROUND: Tick-borne encephalitis (TBE) of western subtype causes long-term morbidity and is considered a health problem in Scandinavia, eastern and central parts of Europe and Russia. The pathophysiology is not fully elucidated. As TBE RNA is rarely demonstrable in cerebrospinal fluid (CSF) the kinetics of the CSF antibody response to the disease has attracted attention. OBJECTIVES: To investigate the intrathecal TBE-specific antibody response and to correlate its intensity and persistence to the clinical course. To compare indirect, commercially-based ELISA methods indexed against albumin ratio or IgG ratio with the capture ELISA method for the establishment of CSF response. STUDY DESIGN: The specific IgM, IgG and IgA antibody responses in serum and CSF were analysed in 69 Swedish patients included in a prospective study of TBE from the acute phase up to 11-13 months after onset. RESULTS: Antibody response by all three classes was demonstrable in serum and CSF. All methods were useful, but capture technique was the most sensitive and results were easiest to interpret. Peak IgM activity was seen early during the disease and persisted after 6 weeks. Maximum IgG levels were encountered in late convalescent samples (median 6 weeks). Intrathecal antibody production was demonstrable in nearly all patients: in 41% days 0-6, in 97% days 7-19, in 98% days 21-61 and-at lower levels-in 84% of the patients after 1 year (50/52 of CSF-serum sampled in the interval 11-61 days). Day 9 after onset, patients with dominating encephalitic symptoms showed significantly lower intrathecal IgM activity. The persistence of serum and CSF antibodies did not correlate to severity of disease. CONCLUSIONS: Capture IgM and IgG assays were superior to indirect ELISA. Low early CSF IgM response correlated to encephalitic symptoms, otherwise the intensity and duration of intrathecal antibody response were of limited value for the prediction of clinical course and long-term outcome.

Adolescent↗

PubMed1997

Haemophilus influenzae and Streptococcus pneumoniae induce different intracerebral mRNA cytokine patterns during the course of experimental bacterial meningitis.

Using in situ hybridization with radiolabelled oligonucleotide probes, we studied the mRNA expression of IL-1beta, IL-4, IL-6, IL-10, IL-12, tumour necrosis factor-alpha (TNF-alpha), TNF-beta, interferon-gamma (IFN-gamma), and transforming growth factor-beta (TGF-beta) in the brain during the lethal course of experimental meningitis in a rat model inoculated intracisternally with Haemophilus influenzae type b (Hib) or Streptococcus pneumoniae and in uninfected control rats inoculated with the same volume of PBS. The production of IL-1beta, IL-4, IL-6 and IFN-gamma was also evaluated by immunohistochemistry. In the brain of Hib-inoculated rats, there was marked mRNA expression of IL-1beta, IL-6, TNF-alpha, IL-12 and IFN-gamma. IL-1beta, IL-6 and TNF-alpha were up-regulated throughout the observation period at 2, 8 and 18 h post-inoculation (p.i.), with similar patterns of induction. The Th1 cytokines IFN-gamma and TNF-beta were up-regulated within 8 h p.i. IL-10 and TGF-beta were down-regulated at 18 h p.i., while IL-4 was not detected. In contrast, the brain of S. pneumoniae-inoculated rats showed lower levels of IL-1beta, IL-6 and TNF-alpha, but higher levels of TNF-beta and detectable mRNA expression of IL-4 when compared with Hib-inoculated rats. IL-12, IFN-gamma, IL-10 and TGF-beta exhibited similar patterns of induction in the brains of Hib- and S. pneumoniae-inoculated rats. At 18 h p.i., immunohistochemistry showed similar patterns of IL-1beta, IL-4, IL-6 and IFN-gamma as mRNA expression in the brains of Hib- and S. pneumoniae-inoculated rats. The differences of cytokine profiles induced by the two bacterial strains may imply that different immunomodulating approaches should be considered, depending on etiology.

Animals↗

PubMed1996

A 10-year follow-up study of tick-borne encephalitis in the Stockholm area and a review of the literature: need for a vaccination strategy.

143 people treated for tick-borne encephalitis (TBE) were included in a retrospective follow-up study. Sequelae and epidemiological characteristics in 114 individuals were analysed. The case fatality rate and the prevalence of residual paresis were low, 1.4 and 2.7%, respectively. However, 40 (35.7%) individuals were found to have a postencephalitic syndrome after a median follow-up time of 47 months, and a majority (77.5%) of these were classified as moderate to severe. Various mental disorders, balance and co-ordination disorders and headache were the most frequently reported symptoms. Increasing age was correlated to a longer duration of hospital stay, longer convalescence and increased risk of permanent sequelae. Results from a neuropsychiatric questionnaire showed marked differences between the subjects with sequelae compared to controls. 57% had noticed a tick bite before admission, and 48% were aware of at least one person in their environment who previously had contracted TBE. 79% were permanent residents or visited endemic areas often and regularly. In conclusion, we have found that TBE in the Stockholm area has a low case fatality rate, but gives rise to a considerable number of different neurological and mental sequelae, which justifies vaccination of a defined risk population in endemic areas.

Adolescent↗

PubMed1996

Incidence and prognosis of meningitis due to Haemophilus influenzae, Streptococcus pneumoniae and Neisseria meningitidis in Sweden.

The incidence, concomitant conditions and case fatality rate of Haemophilus influenzae (Hi) and pneumococcal meningitis and of invasive meningococcal infections were studied retrospectively in Sweden (population 8.4 million) for the years 1987-89, the period before vaccination against Hi type b started. A total of 1,019 cases with culture-verified infection were found. The incidence rates per 100,000 per year were 1.8 for Hi meningitis, 1.2 for pneumococcal meningitis and 1.0 for invasive meningococcal infections. The age-specific incidence was highest in the 3-23 months age group for the 3 bacterial species. Pneumococcal meningitis was common in individuals > or = 60 years and meningococcal infections in the age-group 10-24 years. A serious concomitant condition was known in 57% of all patients with pneumococcal meningitis while this was uncommon for the other organisms. The case fatality rate was 2% for Hi meningitis, 24% for pneumococcal meningitis and 10% for meningococcal infections. All 81 pneumococcal isolates which had been serotyped belonged to serotypes in the 23-valent pneumococcal vaccine. Of the meningococcal isolates, 65% belonged to serogroup B. In conclusion, the high incidence of Hib meningitis justifies general Hib vaccination. Development of a vaccine against N. meningitidis group B should have high priority. Furthermore, improved pneumococcal vaccines are needed for patients with predisposing conditions. The currently available pneumococcal polysaccharide vaccine seems to be underused.

Adolescent↗

PubMed1996

No findings of enteroviruses in Swedish patients with chronic fatigue syndrome.

Enteroviruses have been proposed to cause an immune complex disease in the chronic fatigue syndrome. Altogether 34 patients with the chronic fatigue syndrome, according to criteria of the Centers for Disease Control, USA, were studied evenly over the seasons for the possible presence of a chronic enterovirus infection. In 11 patients, 1-5 faecal samples were collected at about 6 month intervals for virus isolation before and after acid treatment, followed by ultracetrifugation at pH 3 to dissolve possible enterovirus-antibody complexes. Another 14 fecal samples were subjected to routine virus isolation alone. Seven pairs of serum-cerebrospinal fluid samples were analysed for cross-reactive IgG antibody activity to enteroviruses. In 29 patients a muscle biopsy was collected for enterovirus polymerase chain reaction (PCR). We were unable to identify enteroviruses in any of these samples by any of these techniques. Our study does not confirm evidence for persistent enterovirus infection in the chronic fatigue syndrome.

Acids↗