Spontaneous Resolution of Hemophagocytic Syndrome Associated with Acute Parvovirus B19 Infection and Concomitant Epstein-Barr Virus Reactivation in an Otherwise Healthy Adult

Reported here is the case of a patient who spontaneously recovered from hemophagocytic syndrome associated with acute B19 infection and concomitant Epstein-Barr virus reactivation. The previously healthy 37-year-old-man was hospitalized after 10 days of high fever, arthralgia and arthritis and was determined to have hemophagocytic syndrome. Immunoglobulin (Ig) M antibodies to Epstein-Barr virus (EBV) capsid antigen, early antigen and parvovirus B19 (B19) were found. B19 DNA and low-level EBV DNA were detected in bone marrow, serum and peripheral blood mononuclear cells. The patient recovered spontaneously without any treatment. Two months later anti-B19 IgG antibodies were detected, while at 9-month follow-up, anti-B19 IgM antibodies were no longer detectable and B19 DNA had disappeared from serum. To the best of our knowledge, this is the first report of spontaneous resolution of hemophagocytic syndrome associated with acute B19 infection and concomitant EBV reactivation in an otherwise healthy adult. Electronic Publication     

Epstein-Barr Virus (EBV) DNA in Sera of Patients with Primary EBV Infection

Detection of Epstein-Barr Virus (EBV) DNA by PCR in serum had a sensitivity of 80%, a specificity of 94%, and positive and negative predictive values of 95 and 79%, respectively, for the diagnosis of primary EBV infection. We suggest that this is a useful addition to the panel of tests used for this purpose.     

Investigation on the Maternal-Infantile Infection with Human Parvovirus B19

With the investigations on pregnant women and newbornsinfected withToxoplasma, rubella virus, cytomegalovirus,herpes simplex virus (TORCH), it was found that humanparvovirus B19 (B19 virus), which belongs to the familyParvoviridae and the genus Erythrovir…     

Parvovirus B19 Infection in an HIV-Infected Patient with Febrile Pancytopenia and Acute Hepatitis

 The case of a 34-year-old male patient with HIV infection referred for severe febrile pancytopenia is reported. Clinical and laboratory evaluations revealed acute hepatitis B infection and concomitant parvovirus B19 infection. The patient died just before treatment with immune globulin was to be administered. Parvovirus B19 has been found to cause a wide variety of hematologic disorders such as neutropenia, thrombocytopenia, pancytopenia, and hemophagocytic syndrome. The role of parvovirus B19 in the pathogenesis of bone marrow or liver involvement is briefly discussed.     

Association of Inconclusive Sera for Human Immunodeficiency Virus Infection with Malaria and Epstein-Barr Virus Infection in Central Africa

Among 464 sera from adults in Cameroon, 56 (12.1%) gave inconclusive HIV serology. All were negative for HIV-1 DNA; 44.6% (n = 25) were significantly associated with Plasmodium (42.8%) or Epstein-Barr virus (EBV) (17.8%) infections. In Central Africa, sera giving inconclusive results for HIV are frequently associated with malaria, EBV infection, or both.     

Comparison of a Multiplexed Herpes Simplex Virus Type-Specific Immunoglobulin G Serology Assay to Immunoblot, Western Blot, and Enzyme-Linked Immunosorbent Assays

The human herpes simplex virus (HSV) is highly pathogenic, with infections caused by two distinct antigenic types, HSV-1 and HSV-2. Differentiation of antibodies to these specific antigens can provide useful information for the diagnosis of subclinical or undiagnosed HSV-2 infections, as well as for reducing the risk of maternal transfer of HSV to the neonate. In this study, a multiplex assay capable of concurrent detection of HSV-1 and -2 immunoglobulin G (IgG) antibodies was compared to immunoblot, Western blot, and enzyme-linked immunosorbent assays. Agreement of the multiplex assay was 95% or greater (n = 332) for both HSV-1 and -2 compared to the three assays. Sensitivities for HSV-1 ranged from 94.9 to 97.9%, with specificities of 93 to 97%. For HSV-2, the sensitivity and specificity ranges were 92.6 to 98.9% and 98.3 to 98.7%, respectively. Our studies show that the multiplexed microsphere-based assay offers a sensitive and specific alternative method for the detection HSV-1 and -2 type-specific antibodies. Advantages of the multiplex assay include multiple results per assay, the inclusion of internal controls for each specimen, and higher throughput of results.     

Novel Approach for Specific Detection of Herpes Simplex Virus Type 1 and 2 Antibodies and Immunoglobulin G and M Antibodies

Recently a few new herpes simplex virus (HSV) type-specific serological diagnostic tests have been introduced to the commercial market, but these tests have some limitations. Moreover, it is not yet clear which commercial test can be regarded as a “gold standard” for the serodiagnosis of HSV infections. In order to improve the clinical diagnostic value of serological tests for the detection of HSV infections, we developed novel, competition-based enzyme-linked immunosorbent assays for the specific determination of HSV type 2 antibodies (SeroHSV2) and HSV type 1 antibodies (SeroHSV1) and two complementary tests for the detection of HSV immunoglobulin M (IgM) and IgG antibodies (SeroHSV IgM and SeroHSV IgG). These four new kits were evaluated in comparison with some commercial kits for the detection of HSV antibodies that are commonly used at present in Israeli clinical laboratories. The results indicate that SeroHSV2 is highly sensitive (>92%) and highly specific (>94%). SeroHSV2 does not cross-react with other alphaherpesvirus antibodies. SeroHSV1 is highly sensitive (>94%) and specific (>91%) compared to four commercial available kits. SeroHSV IgM is highly specific (>92%) in comparison with other commercial HSV IgM tests. The sensitivity of SeroHSV IgM ranges between 50 and 70% compared to these tests. Further investigation of the discrepant results obtained by using in-house competition tests indicated that SeroHSV IgM is more sensitive. SeroHSV IgG was also found to be highly sensitive (>94%) and highly specific (>92%) compared to the other commercial HSV IgG tests.     

Accuracy of AccessBio Immunoglobulin M and Total Antibody Rapid Immunochromatographic Assays for the Diagnosis of Acute Scrub Typhus Infection

Using archived samples, we assessed the diagnostic capacity of a rapid immunochromatographic test (ICT) for the detection of Orientia tsutsugamushi IgM and total antibodies to aid with the diagnosis of acute scrub typhus infection in febrile patients in Laos. The sensitivity and the specificity of the ICT for the detection of IgM were 96.8% (121/125 samples; 95% confidence interval [CI], 92.1 to 99.1%) and 93.3% (98/105 samples; 95% CI, 86.7 to 97.3%), respectively. For the detection of total antibodies, the sensitivity was 97.6% (122/125 samples; 95% CI, 93.1 to 99.5%), but the specificity was much lower, at 71.4% (75/105 samples; 95% CI, 61.8 to 79.8%).Scrub typhus, caused by Orientia tsutsugamushi, is an important acute febrile illness in the Asia-Pacific region. As very few health facilities have accessible accurate diagnostic tests, the diagnosis of scrub fever must be based on clinical features. However, this is difficult because the clinical symptoms and signs are similar to those of many other febrile diseases, such as murine typhus, leptospirosis, and dengue virus infection. The diagnosis of scrub typhus infection has relied on the detection of O. tsutsugamushi antibodies during the acute phase of the disease, and the “gold standard” assay is the indirect immunofluorescence antibody assay (IFA) (9). The development of rapid, diagnostic tests by the use of immunochromatographic test (ICT) technologies has provided a mechanism for point-of-care serological testing. The objective of the study described here was to assess the diagnostic capacities of two commercial rapid ICTs for the detection of O. tsutsugamushi IgM and whole antibodies to aid with the diagnosis of acute scrub typhus infection by the use of stored, characterized sera collected from febrile patients in the tropical environment of the Lao People''s Democratic Republic (Laos) and Thailand where scrub typhus is endemic.     

Efficiency of Reconstitution of Immunoglobulin G from Blood Specimens Dried on Filter Paper and Utility in Herpes Simplex Virus Type-Specific Serology Screening

The performance of studies using sera from remote locations is greatly facilitated if whole-blood samples dried on filter paper are shown to be compatible with the serologic assay being employed. Since dried blood samples do not require immediate refrigeration, occupy little space, and are easily transported, they may be used for evaluating the seroprevalence of herpes simplex virus type 1 (HSV-1) and HSV-2 in geographic locations where laboratory resources are limited. We evaluated the utility of dried blood samples for the detection of type-specific HSV antibodies. The efficiency of using immunoglobulin G (IgG) eluted from dried blood samples was found to be consistent with measurement of IgG concentrations in most corresponding serum samples. The ratio of the mean IgG concentration for all dried blood samples to the mean IgG concentration for the corresponding sera was 1:29. When the 1:29 ratio was applied to each of the 22 pairs of samples, there was a deviation of less than 15% between concentrations in the dried blood sample and in the corresponding serum sample in 19 of the pairs. No positive or negative bias was detected for the IgG eluted from dried blood. The presence of HSV-1 and HSV-2 antibodies was determined in the paired dried blood and serum samples, and no differences in the HSV serostatuses were detected for 43 of the 44 pairs. One pair's serostatus varied, with the serum sample being weakly positive for HSV-1 and the dried blood sample results being equivocal. The detection of HSV antibodies was generally consistent for dried blood samples stored frozen for over 1 year or at room temperature for 30 days, although decreased reactivities were found in a few samples.     

Isolation of West Nile Virus from Urine Samples of Patients with Acute Infection

This study demonstrated that West Nile virus (WNV) excreted in the urine of patients with acute infection can be isolated in cell cultures. In addition, the protocols for WNV isolation from urine samples were standardized, and factors that may affect the efficiency of WNV isolation were identified.     

Mapping of the Ex Vivo Cellular Immune Response Against the Complete Human Parvovirus B19 Genome During Acute Infection

In parallel with the Th1/Th2 dichotomy, macrophages are capable of developing into functionally and molecularly distinct subpopulations, due to differences in, for example cytokine environment and pathological conditions. While the best-studied, classically activated macrophage is induced by type I stimuli such as IFN-γ, a type II cytokine environment antagonizes the classical activation of macrophages and is capable of alternatively activating macrophages. However, molecular markers associated with these type II cytokine-dependent, alternatively activated macrophages remain scarce. Besides the earlier documented markers macrophage mannose receptor and arginase 1, we recently demonstrated that murine alternatively activated macrophages are characterized by increased expression of FIZZ1 and Ym. We now report that expression of the two members of the mouse macrophage galactose-type C-type lectin gene family, termed mMGL1 and mMGL2, is induced in diverse populations of alternatively activated macrophages, including peritoneal macrophages elicited during infection with the protozoan Trypanosoma brucei or the Helminth Taenia crassiceps , and alveolar macrophages elicited in a mouse model of allergic asthma. We also demonstrate that, in vitro , interleukin-4 and interleukin-13 upregulate mMGL1 and mMGL2 expression and that, in vivo , induction of mMGL1 and mMGL2 is dependent on interleukin-4 receptor signalling. Moreover, we show that regulation of MGL expression is similar in human monocytes and monocyte-derived macrophages. Hence, macrophage galactose-type C-type lectins represent novel markers for both murine and human alternatively activated macrophages; thus, paving the way for further characterization of the phenotype of macrophages occurring in Th2 conditions.     

Concentrations of Cytokines, Soluble Interleukin-2 Receptor, and Soluble CD30 in Sera of Patients with Hepatitis B Virus Infection during Acute and Convalescent Phases

The immunoregulatory roles of interleukin-2 (IL-2), IL-4, IL-10, gamma interferon (IFN-γ), tumor necrosis factor alpha (TNF-α), the soluble form of the IL-2 receptor (sIL-2R), and the soluble form of CD30 (sCD30) were evaluated in patients with hepatitis B virus (HBV) infection. Two groups of subjects were studied: 15 healthy individuals without hepatitis antecedents and 15 patients with HBV infection. Blood samples were taken during the acute and convalescent phases. The analysis of the samples was done by the enzyme-linked immunosorbent assay technique. IFN-γ and TNF-α levels decreased in the convalescent phase. IL-10, IL-2, and sIL-2R levels increased in the acute and convalescent phases, while sCD30 levels increased during the acute phase. The IL-4 concentrations decreased in both phases. During the acute phase, IFN-γ and TNF-α induced increases in IL-2, sIL-2R, IL-10, and sCD30 levels in serum, which allowed the development of immunity characterized by the nonreactivity of the HBV surface antigen, the onset of antibodies to the HBV surface antigen (anti-HBs), and normal alanine aminotransferase levels during the convalescent phase. Increased IL-2 levels during the acute phase would stimulate the activities of NK cells and CD8⁺ lymphocytes, which are responsible for viral clearing. The raised sIL-2R levels reveal activation of T lymphocytes and control of the IL-2-dependent immune response. The sCD30 increment during the acute phase reflects the greater activation of the Th2 cellular phenotype. Its decrease in the convalescent phase points out the decrease in the level of HBV replication. The increase in IL-10 levels could result in a decrease in IL-4 levels and modulate IFN-γ and TNF-α levels during both phases of disease, allowing the maintenance of anti-HBs concentrations.     

Production of Specific Antibodies by Cerebrospinal Fluid Lymphocytes in Patients with Herpes Zoster, Mumps Meningitis and Herpes Simplex Virus Encephalitis

We applied a new method consisting of short-term culture (18 h) of lymphocytes from cerebrospinal fluid (CSF-L) and peripheral blood (PBL) in viral antigen-coated ELISA plates and subsequent measurement of IgG and IgM antibodies bound to antigen. Utilizing mumps virus, herpes simplex virus (HSV), varicella zoster virus (VZV), and measles virus as antigens, we demonstrated production by CSF-L of antibodies against the aetiological agent only in all patients with mumps meningitis and HSV encephalitis and also in all patients with herpes zoster without central nervous system (CNS) symptoms. This might be considered as direct evidence that specific antibodies are produced within the CNS in inflammatory nervous system diseases. CSF-L usually produced higher amounts of antibodies than the corresponding number of PBL. In comparison with concentrations of free antibodies determined in parallel, our method had higher specificity and sensitivity and gave more precise information about the antibody response in infections of the nervous system.     

Detection and Direct Typing of Herpes Simplex Virus in Perianal Ulcers of Patients with AIDS by PCR

The presence of herpes simplex virus type 1 (HSV-1) and HSV-2 in perianal ulcerations of 41 AIDS patients was assessed by virus culture and a type-specific PCR-based assay. HSV was isolated from the lesion site in 24 of 41 (58.5%) patients, and HSV DNA was detected by PCR in all 24 (100%) of these specimens. Additionally, PCR was used to detect HSV DNA in 12 of 17 (70.5%) HSV culture-negative samples. Thus, HSV genomic sequences could be demonstrated in 36 of 41 (87.8%) perianal ulcers in this series. Full agreement in HSV typing by either immunodot assay or PCR was seen in 24 samples that were positive by both virus culture and PCR. HSV-2 was demonstrated in 35 of 36 (97.2%) HSV-positive samples.     

Parvovirus B19 Infection Localized in the Intestinal Mucosa and Associated with Severe Inflammatory Bowel Disease

Infection by human parvovirus B19 is widespread and can be associated with a wide range of different pathologies and clinical manifestations. We provide the first evidence of localization of an active parvovirus B19 infection in the intestinal mucosa and its association with a severe inflammatory bowel disease, characterized by duodenal villous atrophy with increased intraepithelial lymphocytes and inflammatory infiltrates in the colonic mucosa. Virus in the intestinal mucosa was detected in cells of the inflammatory infiltrate, identified as T lymphocytes and selectively localized in sites of active tissue degeneration.     

Diagnosis of Dengue Virus Infection by the Visual and Simple AuBioDOT Immunoglobulin M Capture System

The Dengue IgM Capture ELISA (MAC-ELISA) is the immunoenzymatic system recommended by the Pan American Health Organization and the World Health Organization for the serological diagnosis of dengue virus infection due to its high sensitivity, ease of performance, and use of a single acute-phase serum sample. However, tests with this enzyme-linked immunosorbent assay (ELISA) system are time-consuming and require equipment for washing, incubation, and reading of the results. AuBioDOT is a multistep visual diagnostic immunoassay that uses technology based on the immunoglobulin M (IgM) capture ELISA principle. This system uses white polyethylene opaque plates as the solid phase, colloidal gold as the marker, and silver ion amplification. It does not require special equipment, it is totally manually operated, and it can be performed in less than 1 h. The sensitivity and specificity of AuBioDOT for the detection of anti-dengue virus IgM antibodies were studied with a panel of 336 serum samples (150 serum samples from patients with suspected or serologically confirmed dengue virus infection, 186 serum samples from healthy blood donors and patients without dengue virus infection). The results were compared with those obtained by the MAC-ELISA. A sensitivity of 97.7% and a specificity of 97.1% were obtained. The concordance of the two tests was 97.3%, with a kappa index of 0.94. The application of AuBioDOT for the detection of anti-dengue virus IgM antibodies is recommended as an alternative method for the diagnosis of dengue virus infection, both for clinical diagnosis and for seroepidemiological surveillance. The system is useful under field conditions and in laboratories and requires little equipment.     

Hepatitis B Virus DNA in Sera of Blood Donors and of Patients Infected with Hepatitis C Virus and Human Immunodeficiency Virus

With the use of PCR, we searched for hepatitis B virus (HBV) DNA in serum samples from 415 HBsAg-negative, anti-HBc-positive patients: 150 were blood donors, 106 had only hepatitis C virus (HCV) infection, and 159 had human immunodeficiency virus (HIV) infection (of which 88 were HCV positive and 71 were HCV negative). HBV DNA was detected in 4% of blood donors, 3.4% of HIV- and HCV-positive patients, and 24% of HCV-positive patients.     

Frequent Detection of Herpes Simplex Virus Antigen in Skin and Peripheral Blood CD34+ Mononuclear Cells from Patients with Graft-versus-Host Disease

Viruses are implicated in the initiation or flare of graft-versus-host disease (GVHD) by virtue of their ability to activate antigen-presenting dendritic cells (DC). Herpes simplex virus (HSV) infects circulating CD34+ stem cell progenitors, favoring their differentiation into skin homing DC (CD1a+ Langerhans cells) that contribute to the development of an inflammatory skin rash known as HSV-associated erythema multiforme (HAEM). Following on these findings, we conducted a prospective study to examine whether HSV is also associated with GVHD. Skin biopsies and peripheral blood mononuclear cells (PBMC) were collected from 37 consecutive patients on admission before and after allogeneic hematopoietic stem cell transplantation (HSCT) and examined for HSV antigen (Pol) expression and the presence of Pol+CD34+ and Pol+CD1a+ cells. Sixteen patients developed a skin rash that was histopathologically consistent with GVHD (group I), 3 patients had a rash that was not GVHD (group II, EM-like) and 18 patients did not develop any rash after HSCT (group III). Skin biopsies from the group I patients were Pol negative pre-HSCT (baseline) but became Pol+ after the diagnosis of GVHD. The GVHD biopsies also contained Pol+CD34+ and Pol+CD1a+ cells, and these patients had a significant percentage of circulating Pol+CD34+ and Pol+CD1a+ PBMC. By contrast, the group II patients had Pol+ skin cells and Pol+CD34+ circulating PBMC at baseline that decreased post-HSCT. The group III patients had Pol negative skin and very few circulating Pol+CD34+ and Pol+CD1a+ PBMC at baseline that were not significantly changed post-HSCT. The data associate skin GVHD with HSV reactivation during conditioning and its propensity for nonreplicative infection of CD34+ PBMC that induces DC activation. Further studies are needed to better elucidate this association.