Marker Of Active Infection Research Articles

Antibodies to recombinant decorin-binding proteins A and B in the cerebrospinal fluid of patients with Lyme neuroborreliosis

Cerebrospinal fluid (CSF) and serum samples from 34 patients with proven neuroborreliosis (NB) and 22 patients with suspected neuroborreliosis (SNB) from Finland were analysed for antibodies to decorin-binding proteins A (DbpA) and B (DbpB). Antibodies to recombinant protein antigens originating from Borrelia burgdorferi sensu stricto, B. afzelii, or B. garinii species were studied by enzyme-linked immunosorbent assay (ELISA). Of the 34 patients with NB, 100% of the CSF and 88% of the serum samples had IgG antibodies to 1 to 3 variants of DbpA and 79% of the CSF and 70% of the serum samples were positive for 1 to 3 DbpB variants. Antibodies to DbpB seemed to be associated with lymphocytic pleocytosis in the CSF and short duration of the disease, whereas antibodies to DbpA in the CSF were observed irrespective of the duration of the disease and lymphocytic pleocytosis. Among the variant antigens, CSF reactivity was mainly with the DbpB from B. garinii, whereas positivity with the DbpA from B. afzelii or B. garinii predominated. The results suggest that CSF antibodies to DbpB might be useful as a marker of active infection whereas antibodies to DbpA seem to persist a long time after acute phases of NB.

Is Human Herpesvirus–6 DNA in Plasma the Right Marker for Active Infection?

Is Human Herpesvirus–6 DNA in Plasma the Right Marker for Active Infection?

Detection of Immune Complexes Is Not Independent of Detection of Antibodies in Lyme Disease Patients and Does Not Confirm Active Infection with Borrelia burgdorferi

The Borrelia burgdorferi-specific immune complex (IC) test, which uses polyethylene glycol (PEG) precipitation to isolate ICs from serum, has been used as a research test in the laboratory diagnosis of early Lyme disease (LD) and has been proposed as a marker of active infection. We examined whether B. burgdorferi-specific antibodies were present within PEG-precipitated ICs (PEG-ICs) in patients with LD, posttreatment Lyme disease syndrome, and controls, including individuals who received the outer surface protein A (OspA) vaccine. Using a B. burgdorferi whole-cell enzyme-linked immunosorbent assay (ELISA), we obtained positive PEG-IC results not only in patients with a history of LD, but also in individuals vaccinated with OspA vaccine. The frequency of positive PEG-IC ELISAs in OspA vaccinees was significantly higher with ELISA-reactive than with ELISA-negative unprocessed serum samples (P=0.001), demonstrating dependency between the tests. Similar results were found using samples from rhesus macaques infected with B. burgdorferi, uninfected macaques vaccinated with OspA, and controls. Therefore, testing for the presence of antibodies against B. burgdorferi in PEG-IC preparations is not more likely to reflect active infection than testing in unprocessed serum and should not be used in individuals who received the OspA vaccine.

Usefulness of a Comprehensive PCR-Based Assay for Human Herpes Viral DNA in Blood Mononuclear Cell Samples

Human herpes virus (HHV) is well known to reactivate in immunocompromised situations and plays an immunomodulatory role leading to indirect effects through viral replication to the host. The aim of this study was to determine the laboratory and clinical relevance of a comprehensive PCR-based assay for detecting eight HHVs, which are lymphotropic and cause disease in humans. Using 176 samples collected from 146 specimens of peripheral blood, 12 skin nodules, 11 lymph nodes and 7 others of patients who were suspected to have adult T cell leukemia (ATL), the PCR-based assay was validated to simultaneously detect one or more herpes viral DNA with two consensus primer sets. Although most samples were seropositive for either of the HHVs, only 50% of them were positive for either herpes viral DNA with EBV in 76%, HHV-6 in 14% and VZV in 9%. Furthermore, such a herpes viral DNA positive status was not always associated with clinical symptoms relating to the virus, implying active replication in the blood cells, but being asymptomatic. HHV-8 viral DNA, although Kaposi's sarcoma has been reported to be complicated with ATL, was not demonstrable. HHV-6B was detected only in HTLV-1 healthy carriers and ATL patients, and may imply a co-factor role with HTLV-1. This PCR-based assay provides a herpes viral infectious status compensatory for virus-serology and is a clinically relevant laboratory test, serving as a screening marker for active infection.

Detection of Human Herpesvirus 6 in Plasma of Children with Primary Infection and Immunosuppressed Patients by Polymerase Chain Reaction

A sensitive and specific polymerase chain reaction method for the detection of human herpesvirus 6 (HHV-6) DNA in serum or plasma has been developed. In total, 157 human serum or plasma samples were studied. HHV-6 DNA was detected in 6 (85.7%) of 7 children with exanthem subitum, 3 (23.1%) of 13 bone marrow transplant (BMT) recipients, 4 (22.2%) of 18 human immunodeficiency virus (HIV)-infected patients, 1 (2.6%) of 39 patients with chronic fatigue syndrome, and none of 37 healthy adults. In the HHV-6-positive BMT recipients, HHV-6 plasma DNA was transiently detected during episodes of fever and respiratory infection. In children with exanthem subitum and in 1 HIV-infected patient, the HHV-6 strains were characterized as variant B, whereas variant A was detected in all other patients. Detection of viral DNA in serum or plasma is a marker of active infection that can be used to investigate the role of HHV-6 in human disease.

Congenital cytomegalovirus infection: on the relation between type and time of maternal infection and infant's symptoms.

Maternal sera from 45 live-born infants with congenital cytomegalovirus (CMV) infection and 4 cases of legal abortion were analysed for CMV IgG and IgM. The investigation included cases from routine work and prospective studies of unselected infants. The purpose was to elucidate the relation between the maternal type and time of infection and the signs and symptoms of the offspring at birth and follow-up. Serological patterns compatible with primary maternal infection during trimesters I and II, but also with secondary infection (in at least 1 case), were associated with infant sequelae or death. Asymptomatic infant infection was found after primary infection in trimesters II and III and after secondary infection. Virus could not be isolated from some of the fetuses legally aborted due to primary maternal infection in trimester I. Attempts to demonstrate CMV IgM activity as a marker of active infection in sera from early pregnancy (period of legal abortion) were successful in only half of the 10 cases with infant sequelae or death. Symptoms at birth were prognostically serious, but the further course was sometimes uneventful even in infants with neonatal signs of cerebral infection. A few children without initial symptoms developed sequelae (impairment of hearing).

Role of hepatitis b virus in primary liver cancer

There is an excess prevalence of markers of active infection with hepatitis B virus in patients with primary liver cancer in many parts of the world. Early age of infection with hepatitis B virus is likely to be an important factor, resulting in persistent infection that may progress to chronic liver damage. Results of recent experimental studies are consistent with integration of hepatitis B viral DNA with host cell DNA molecules. It is likely that primary liver cancer is the cumulative result of several cofactors including infection with hepatitis B virus; genetic, immunologic, hormonal, and nutritional factors; and environmental factors including mycotoxins and chemical carcinogens.