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P Juto

Publications and source records attributed to P Juto.

At least 19 recordsLinked to original sources
PubMed2005

High titres of IgA antibodies to enterovirus in fulminant type-1 diabetes.

AIMS/HYPOTHESIS: We have recently proposed that fulminant type-1 diabetes is a novel subtype of type-1 diabetes with abrupt onset of insulin-deficient hyperglycaemia without islet-related autoantibodies. The pathogenesis is still unknown, but flu-like symptoms are frequently observed before the onset of disease of this subtype. Enterovirus infection is a candidate environmental factor causing type-1 diabetes. The aim of this study was to determine whether enterovirus infection contributes to the development of fulminant type-1 diabetes. METHODS: We investigated 19 patients with recent-onset fulminant type-1 diabetes, 18 patients with recent-onset typical type-1A diabetes, and 19 healthy controls. IgM, IgG, and IgA subclasses of antibodies to enterovirus were determined by ELISA. RESULTS: IgA antibody titres to enterovirus were significantly higher in fulminant type-1 diabetes than in typical type-1A diabetes (p=0.033) and controls (p=0.0003). IgM antibodies to enterovirus were not detected in any subject. IgG titres were lower in autoimmune diabetes than fulminant type and controls (p=0.014 and 0.019, respectively). CONCLUSIONS/INTERPRETATION: High titres of enterovirus IgA antibodies in serum suggest recurrent enterovirus infection in fulminant type-1 diabetic patients, indicating higher susceptibility to enteroviral infections among them. Such infections might have pathogenetic importance in the triggering of fulminant type-1 diabetes.

Adult↗
PubMed2004

An altered immune response to Epstein-Barr virus in multiple sclerosis: a prospective study.

OBJECTIVE: To investigate the association between human herpesviruses and multiple sclerosis (MS), as well as between measles virus and MS. METHODS: The authors identified prospectively collected serum samples from 73 MS cases and retrospective sera from 161 MS cases in two population-based serum bank registers. Analyses of IgG antibody responses in cases and matched referents were performed for Epstein-Barr virus (EBV [EBNA-1 and VCA]), human herpesvirus 6 (HHV-6), herpes simplex virus (HSV), varicella zoster virus (VZV), and measles. RESULTS: All cases showed signs of past EBV infection. High activity to EBNA-1 and HHV-6 significantly (borderline significance for HHV-6) increased the risk for MS in prospective sera. A discrepancy between activities to EBNA-1 and VCA was striking in MS samples collected less than 5 years before relapsing-remitting MS onset, where high activity to EBNA-1 significantly increased, and high VCA activity significantly decreased the risk for MS. There was no support for major causal roles for HSV, VZV, or measles. CONCLUSION: Individuals who will develop MS exhibit an altered immune response against the EBV virus characterized by a high IgG activity to EBNA-1 in the absence of high activity to VCA, this being most pronounced in the 5-year period preceding MS onset.

Adolescent↗
PubMed2001

Screening for adult coeliac disease - which serological marker(s) to use?

OBJECTIVE: To determine which serological marker(s) to use when screening for coeliac disease. DESIGN: In a population-based cross-sectional study we compared the use of antigliadin antibodies (AGA) of isotypes IgA and IgG, antiendomysial antibodies (AEA) of isotype IgA and antitransglutaminase antibodies (ATGA) of isotype IgA for detecting coeliac disease amongst adults. SETTING: Northern Sweden. SUBJECTS: A total of 1850 of 2500 (74%) invited adults (aged 25-74 years) who were randomly selected from the population register after stratification for age and sex. MAIN OUTCOME MEASURES: The sensitivity, specificity and predictive values of the AGA, ATGA and AEA tests. RESULTS: Nine cases of biopsy proven, previously undiagnosed coeliac disease were detected by screening. The sensitivity of both ATGA and AEA was 100% whilst AGA IgA and IgG both had a sensitivity of 89%. The AEA test had a specificity of 100% whereas the specificities of the ATGA, AGA IgA and IgG tests were 97, 96 and 78%, respectively. The positive predictive value for the AEA test was 100%, whereas it was considerably lower for the other tests (ATGA > AGA IgA > AGA IgG), with further decreases for all tests when shifting from a clinical to a screening situation. CONCLUSIONS: When screening for coeliac disease we suggest a serial testing approach, i.e. an initial ATGA test and, when positive, followed by an AEA test, provided that IgA deficiency has been excluded. However, assessment of the small intestinal mucosal morphology is still required to ascertain the diagnosis.

Adult↗
PubMed2001

New automated immunoassay measuring immunoglobulin A antigliadin antibodies for prediction of celiac disease in childhood.

The prevalence of celiac disease (CD) in Sweden is about 4 cases per 1,000 people. Screening for CD with serological tests indicates similar high prevalences in many other countries. Between 1 November 1992 and 30 April 1995, 133 children (9 months to 16.7 years of age) with suspected CD were studied. The predictive value (PV) of immunoglobulin A antigliadin antibodies (IgA-AGA) in the serum as assayed with two new commercial automated immunoassays--the Pharmacia CAP System Gliadin IgA FEIA (CAP) and the UNICAP-100 (UNICAP)--and with three "in-house" methods was evaluated using assessment of the small intestinal mucosa morphology as the "gold standard." All serum samples were analyzed for total serum IgA. At presentation the diagnostic sensitivities and specificities of the different tests varied from 0.72 to 0.88 and 0.67 to 0.87, respectively. All methods showed a higher sensitivity for CD in younger children. The area under each assay's receiver operating characteristic curve was calculated and varied between 0.82 and 0.89. The positive and negative PVs for the CAP and UNICAP, which were assays with a high sensitivity and a high specificity, respectively, were estimated. In the clinically selected population (prevalence of CD, 1 in 3) the positive PV was about 55%, and in the general population (prevalence, 1 in 250) it was about 1%. The negative PVs for both CAP and UNICAP were close to 100%; thus, when the AGA test was negative, the risk for CD was small. Interestingly, five children had serum IgA levels below the detection limit (<0.07 g/liter) when on a gluten-free diet, whereas they had normal levels at the time of the first biopsy. In conclusion, the automated immunoassays--based on ImmunoCAP technology--for analysis of IgA-AGA had a reliability comparable to that of the in-house methods.

Adolescent↗
PubMed2000

Serologic evidence of Puumala virus infection in wild moose in northern Sweden.

Puumala (PUU) virus is the causative agent of nephropathia epidemica, the Scandinavian form of hemorrhagic fever with renal syndrome. The infection is acquired by airborne transmission of PUU virus from its rodent reservoir, the bank vole. Besides serologic data indicating that the virus may spread also to heterologous rodents, there is little information on the susceptibility of wild living animals to PUU virus. We studied the occurrence of antibodies to PUU virus in serum samples from 427 wild-living moose, of which 260 originated from the PUU virus-endemic northern and central parts of Sweden and 167 originated from the southern, nonendemic part of Sweden. Samples from 5 animals showed reactivity in an ELISA for recombinant PUU virus nucleocapsid protein, an immunofluorescent assay, and a neutralization test. These 5 animals all originated from the PUU virus-endemic northern part of Sweden. In conclusion, 5 of 260 moose from the endemic region showed convincing serologic evidence of past PUU virus infection. The seroprevalence was low, suggesting that the moose is subjected to endstage infection rather than being part of an enzootic transmission cycle.

Age Distribution↗
PubMed1999

High prevalence of undiagnosed coeliac disease in adults: a Swedish population-based study.

OBJECTIVE: To determine the prevalence of coeliac disease in a population-based sample of Swedish adults. DESIGN: Population-based cross-sectional study. SETTING: Northern Sweden. SUBJECTS: A total of 1894 adults (76%) out of 2500 invited, randomly selected from the population register after stratification for age and sex. MAIN OUTCOME MEASURES: Prevalence of biopsy verified coeliac disease, symptoms of undiagnosed cases, and results of antiendomysium and antigliadin serum antibody tests. RESULTS: Coeliac disease was confirmed by intestinal biopsy showing enteropathy in 10 individuals (seven women and three men), corresponding to a prevalence of 5.3 per 1000 (95% CI = 2.5-9.7). The majority of cases (eight out of 10) had not been diagnosed prior to the screening, although many had symptoms compatible with coeliac disease. All individuals with antiendomysium antibody positivity who were subjected to a small intestinal biopsy had enteropathy. Furthermore, all of them also had elevated levels of antigliadin antibodies type IgA and/or IgG. CONCLUSIONS: Coeliac disease is common, albeit mostly undiagnosed, in Swedish adults. It is likely that the situation is no better in other countries. This highlights the importance of keeping coeliac disease in mind, and of promptly investigating individuals with unexplained, even mild, symptoms compatible with the disease. Serological markers, e.g. antigliadin and antiendomysium antibodies, are useful tools within this active case-finding strategy, although the final diagnosis should be based on an intestinal biopsy demonstrating enteropathy.

Adult↗
PubMed1998

Chlamydia pneumoniae in human abdominal aortic aneurysms.

OBJECTIVES: To investigate the presence of Chlamydia pneumoniae DNA in the wall of infrarenal abdominal aortic aneurysms, and in the wall of non-aneurysmal infrarenal abdominal aortas. DESIGN: Case-control study. MATERIALS AND METHODS: The study group consisted of 40 patients operated transperitoneally for an infrarenal abdominal aortic aneurysm (IAAA) (eight females, 32 males; mean age 69 years, median age 68 years). Specimens from the aneurysm wall were taken peroperatively under sterile conditions. The control group consisted of 40 deceased persons without aortic aneurysms (14 females, 26 males; mean age 71 years, median age 70 years). Specimens from the non-aneurysmal infrarenal aortas (NIAA) were collected within 48 h after death. The specimens from both groups were frozen at -70 degrees C immediately after collection. A nested polymerase chain reaction (PCR) method, using two sets of primers designed to detect a fragment of the major outer membrane protein gene of C. pneumoniae, was used. RESULTS: The detection of C. pneumoniae-specific DNA was significantly higher in the study group (14/40 = 35%) than in the control group (2/40 = 5%); (p = 0.001). No clinical factor predicting the presence of C. pneumoniae in the aneurysm wall, could be found. CONCLUSION: Chlamydia pneumoniae was detected at a significantly higher frequency in the wall of IAAAs than in the wall of NIAAs. Although this finding does not prove that C. pneumoniae causes IAAAs, further studies on the possible role of C. pneumoniae in the pathogenesis of aneurysms should be performed.

Aged↗
PubMed1998

A minority of seropositive wild bank voles (Clethrionomys glareolus) show evidence of current Puumala virus infection.

Bank voles (Clethrionomys glareolus) serve as the reservoir for Puumala (PUU) virus, the aetiologic agent of nephropathia epidemica. The animals are believed to be persistently infected and the occurrence of serum antibodies is usually taken as an evidence of active infection. We found serum antibodies to PUU virus in 42 of 299 wild bank voles captured in a PUU virus endemic area. PUU virus RNA was demonstrated in lung specimens of 11 of these 42 animals and in 2 of them antigen was also found. Thus in the lungs of 31 of 42 seropositive animals neither PUU virus RNA nor antigen was detected. In 2 of 257 seronegative animals, lung specimens showed presence of PUU virus antigen and RNA. Isolation of PUU virus from lung tissue was successful in all 4 antigen-positive bank voles but in none of 16 tested antigen-negative animals. In conclusion, only a minority of bank voles with serum antibodies to PUU virus showed evidence of current infection.

Amino Acid Sequence↗
PubMed1998

High prevalence of Chlamydia pneumoniae DNA in peripheral blood mononuclear cells in patients with cardiovascular disease and in middle-aged blood donors.

Nested polymerase chain reaction (nPCR) demonstrated the presence of Chlamydia pneumoniae-specific DNA in peripheral blood mononuclear cells (PBMC). PBMC samples were obtained from 103 consecutive patients (62 male, 41 female) aged 22-85 years (mean, 64) admitted for coronary angiography because of suspected coronary heart disease and from 52 blood donors (43 male, 9 female) aged 40-64 years (mean, 49). Of the 101 evaluable patients, 60 (59%) were identified by nPCR assay as C. pneumoniae DNA carriers; C. pneumoniae-specific microimmunofluorescence (MIF) serology confirmed exposure to the bacterium in 57 (95%) of the 60 nPCR-positive patients. Among the 52 blood donors, the nPCR assay identified 24 (46%) C. pneumoniae DNA carriers, all of whom were positive by C. pneumoniae-specific serology. Thirty-two patients (32%) and 23 blood donors (44%) were MIF antibody-positive but repeatedly nPCR-negative; Bartonella henselae- or Bartonella quintana-specific antibodies were not detected among any of these subjects. In this study, C. pneumoniae DNA was common in PBMC of patients with coronary heart disease and in middle-aged blood donors.

Adult↗
PubMed1998

Development of humoral cross-reactivity to the nucleocapsid protein of heterologous hantaviruses in nephropathia epidemica.

A hantavirus infection is followed by a prominent antibody response to the viral nucleocapsid protein. Antibodies from patients infected with one hantavirus cross-react to varying degrees with the nucleocapsid protein of other viruses of the genus. We studied the cross-reactivity in serially obtained blood samples from 17 patients with nephropathia epidemica, a European form of hemorrhagic fever with renal syndrome caused by Puumala virus. Recombinant truncated nucleocapsid protein (aa 1-117) of Puumala virus and four other hantaviruses, Hantaan, Seoul, Dobrava and Sin Nombre viruses, were used as antigens in an indirect ELISA. In most patients, an IgG response to the Puumala virus derived recombinant protein was detected within 2-8 days of onset of disease, remained high for 2-5 months, and declined gradually within 2-3 years. All patients had IgG antibodies cross-reacting with the nucleocapsid protein of Sin Nombre virus. The ratio of the ELISA values obtained with Sin Nombre vs. Puumala virus protein as antigen increased with time after onset of disease. To a lesser extent, cross-reacting IgG antibodies also occurred to Hantaan, Seoul, and Dobrava virus antigens. In the acute phase of the disease, two patients showed IgG antibodies to one or more of these viruses whereas 2-5 months later, 11 of 16 patients had IgG antibodies to all three viruses. IgM and IgA responses to the nucleocapsid protein of Puumala virus were transitory and cross-reactivities were weak. In conclusion, after onset of nephropathia epidemica the IgG response to the Puumala virus nucleocapsid protein was associated with a gradually increasing cross-reactivity to the nucleocapsid protein of heterologous hantavirus. Our findings have implications for the interpretation of serological data, both in the diagnostics of nephropathia epidemica and in seroprevalence studies.

Adult↗
PubMed1998

Prevalence of antibodies specific to Puumala virus among farmers in Sweden.

OBJECTIVES: The Puumala virus is the causative agent of nephropathia epidemica, a European form of hemorrhagic fever with a renal syndrome. From its reservoir in bank voles, the virus is spread by airborne transmission to humans. Occupational risks for the acquisition of nephropathia epidemica are not well defined. The prevalence of serum antibodies to Puumala virus was determined for Swedish farmers. From a comparison of the prevalence among farmers from various parts of the country, the assumption that Puumala virus occurs endemically only in the northern and central parts of Sweden was also tested. METHODS: Serum samples from 910 farmers and 663 referents living in various rural parts of Sweden were tested with an enzyme-linked immunosorbent assay, using a recombinant nucleocapsid protein of Puumala virus as the antigen. RESULTS: North of a latitude of 59 degrees N, the prevalence of Puumala virus antibodies was significantly higher among farmers (12.9%) than among referents (6.8%). In the southern areas, antibodies to Puumala virus were rare, and altogether only 2 of 459 persons had antibodies. Seropositive persons did not differ from seronegative ones with regard to blood pressure, and they did not comprise cases of chronic renal disease. CONCLUSIONS: Serological evidence confirmed that the exposure of humans to Puumala virus is firmly restricted to the northern and central parts of Sweden. In addition the evidence indicated that, in this region, farming is associated with an increased risk of contracting hantavirus infection.

Adult↗
PubMed1997

The first human isolate of Puumala virus in Scandinavia as cultured from phytohemagglutinin stimulated leucocytes.

A virus isolate was recovered from blood leucocytes of a patient with nephropathia epidemica (NE). Leucocytes were isolated from EDTA-blood by dextran sedimentation and cultured on monolayers of Vero E6 cells in the presence of phytohemagglutinin (PHA) in roller tubes during the first 72 hours of incubation followed by rolling culture for three weeks in total. Thereafter the first subculture was done in a plastic flask and afterward at at least 6 week intervals. Antigen was first detected after 6 months and 2 weeks of culture. When tested by monoclonal antibodies and patient sera the isolate had the characteristics of a PUU virus. PCR amplification using PUU-specific primers and subsequent partial sequencing of the S and M segments revealed that the Umeå/305/human/95 virus differs from the Finnish PUU Sotkamo rodent prototype virus and is similar but not identical to rodent strains of PUU virus acquired from the same region as the patient isolate. It is we concluded that the first human isolate of the etiologic agent of NE in Scandinavia was recovered from blood leucocytes stimulated with PHA by long-term culture in Vero E6 cells. The isolate belongs to the PUU serotype of hantaviruses as shown by its serologic profile and partial sequencing data.

Adult↗
PubMed1997

Increased plasma levels of soluble CD23 in haemorrhagic fever with renal syndrome; relation to virus-specific IgE.

In 15 consecutive patients hospitalized with nephropathia epidemica, a European form of haemorrhagic fever with renal syndrome (HFRS) caused by Puumala virus, plasma concentrations of soluble CD23 (sCD23) and Puumala virus-specific IgE were determined. In the acute phase of illness, 11/15 patients had increased sCD23 levels (> 91 U/ml), whereas in convalescence, values of 8/10 patients were normalized. Maximal sCD23 values were correlated to maximal concentrations of Puumala virus-specific serum IgE (r = 0.597; P = 0.025). The results are compatible with a known ability of sCD23 to augment IgE production.

Adult↗
PubMed1997

Rapid diagnosis of respiratory Chlamydia pneumoniae infection by nested touchdown polymerase chain reaction compared with culture and antigen detection by EIA.

Chlamydia pneumoniae is a common cause of respiratory tract infection and community-acquired pneumonia. During an extensive outbreak of C. pneumoniae in northern Sweden, 319 respiratory samples from 129 persons were collected. Sputum, throat, and nasopharyngeal samples were obtained and analyzed by nested touchdown polymerase chain reaction (PCR), EIA, and culture in Hep-2 and McCoy cells. Serology was performed by complement fixation and microimmunofluorescence tests. By PCR, 30 patients were diagnosed with C. pneumoniae compared with 26 positive by EIA and 23 by culture. The finding of C. pneumoniae in the respiratory samples was accompanied by serology indicating acute infection in 26 (96%) of 27 patients for whom adequate sera were available. Nested PCR was sensitive and reliable for diagnosing acute respiratory C. pneumoniae infection. Sputum samples had the highest diagnostic efficacy, and the nested type of PCR was superior to one-step PCR. EIA and culture were less sensitive than nested PCR.

Acute Disease↗
PubMed1997

Failure to detect Chlamydia trachomatis in cell culture by using a monoclonal antibody directed against the major outer membrane protein.

Two commercially available monoclonal antibodies for cell culture confirmation of Chlamydia trachomatis were compared in two prospective studies and one large retrospective study. In total, more than 33,000 genital specimens were cultured in parallel and stained with both antibodies, one of which was directed against the major outer membrane protein (MOMP) and one of which was directed against the lipopolysaccharide (LPS). We found the anti-LPS-based assay to be more sensitive and as specific as the anti-MOMP-based assay for C. trachomatis cell culture confirmation of genital specimens.

Antibodies, Bacterial↗
PubMed1997

Evaluation of serological methods for diagnosis of Puumala hantavirus infection (nephropathia epidemica).

Nephropathia epidemica (NE), Puumala (PUU) virus infection, is a febrile disease which is commonly associated with acute renal impairment. To differentiate NE from other acute febrile illnesses, a rapid and reliable serological diagnosis is important, and a number of different protocols have recently been introduced. In the present report we describe a comparative evaluation of six PUU virus immunoglobulin M (IgM) and seven IgG enzyme-linked immunosorbent assay (ELISA) protocols based on native, Escherichia coli-expressed, or baculovirus-expressed nucleocapsid protein (N). Neutralization and immunofluorescence assays were included for comparison. Equally high sensitivities and specificities were obtained with three mu-capture-based IgM ELISAs using native, baculovirus-expressed, and E. coli-expressed N antigens, respectively, and by an ELISA based on purified E. coli-expressed full-length N adsorbed to solid phase. The assays based on truncated amino-terminal N proteins, including a commercially available PUU virus IgM ELISA, all showed lower sensitivities. For detection of PUU virus-specific IgG, ELISAs based on monoclonal antibody-captured native or baculovirus-expressed N antigens showed optimal sensitivities and specificities, while the assays based on E. coli-expressed N did not detect all PUU virus IgG-positive serum samples. A commercially available PUU virus IgG ELISA based on E. coli-expressed amino-terminal N showed a significantly lower sensitivity than those of all other IgG assays.

Antibodies, Viral↗