Epstein-Barr viral load assessment in immunocompetent patients with fulminant infectious mononucleosis

Secondary Hemophagocytic Lymphohistiocytosis in a Young Hispanic Adult

Hemophagocytic lymphohistiocytosis (HLH) is a disease caused by a severe immune system reaction that involves an overwhelming inflammatory response with overproduction of cytokines and hemophagocytosis. HLH is classified as primary HLH or familial HLH (PHLH or FHLH) and secondary HLH. PHLH is due to mutations in several genes that regulate immune cells, while secondary HLH is triggered by a severe illness (viral infections or malignancies) that induce an excessive immune response that is difficult to control. We present a case of a young Hispanic adult female with a medical history of diabetes mellitus type 1 and hepatitis E that was diagnosed with HLH secondary to lymphoma caused by Epstein Barr virus infection. The patient was started on broad-spectrum antibiotics and steroid therapy; however, the patient succumbed to the disease. HLH is associated with high mortality, mainly because it is not a very common entity and patients usually present critically ill and deteriorate very fast. Immunosuppression and treatment of the underlying disorder is the target of the treatment of HLH, however, the prognosis remains poor.

EBV-related Cold Agglutinin Disease Presenting With Conjugated Hyperbilirubinemia: A Pediatric Case Report and Mini Review

Hemolytic anemia occurs in only 1% to 3% of hospitalized patients with infectious mononucleosis. The authors describe an 8-year-old girl without cervical lymphadenopathy or splenomegaly, who presented with conjugated hyperbilirubinemia and was diagnosed with cold agglutinin disease caused by an immunoglobulin M autoantibody with anti-i specificity. Acute Epstein-Barr virus infection was confirmed by serologic and molecular methods. She recovered uneventfully after a 3-week course of methylprednisolone. Epstein-Barr virus infection should be considered in any case of hemolytic anemia associated with hepatic dysfunction, especially when direct antiglobulin test is positive for C3d. In these cases, a course of corticosteroids seems safe and may be beneficial.

Recommendations for the management of hemophagocytic lymphohistiocytosis in adults

Hemophagocytic lymphohistiocytosis (HLH) is a severe hyperinflammatory syndrome induced by aberrantly activated macrophages and cytotoxic T cells. The primary (genetic) form, caused by mutations affecting lymphocyte cytotoxicity and immune regulation, is most common in children, whereas the secondary (acquired) form is most frequent in adults. Secondary HLH is commonly triggered by infections or malignancies but may also be induced by autoinflammatory/autoimmune disorders, in which case it is called macrophage activation syndrome (MAS; or MAS-HLH). Most information on the diagnosis and treatment of HLH comes from the pediatric literature. Although helpful in some adult cases, this raises several challenges. For example, the HLH-2004 diagnostic criteria developed for children are commonly applied but are not validated for adults. Another challenge in HLH diagnosis is that patients may present with a phenotype indistinguishable from sepsis or multiple organ dysfunction syndrome. Treatment algorithms targeting hyperinflammation are frequently based on pediatric protocols, such as HLH-94 and HLH-2004, which may result in overtreatment and unnecessary toxicity in adults. Therefore, dose reductions, individualized tailoring of treatment duration, and an age-dependent modified diagnostic approach are to be considered. Here, we present expert opinions derived from an interdisciplinary working group on adult HLH, sponsored by the Histiocyte Society, to facilitate knowledge transfer between physicians caring for pediatric and adult patients with HLH, with the aim to improve the outcome for adult patients affected by HLH.

Lymphoma and other lymphoproliferative disorders in inflammatory bowel disease: a review

The lymphoproliferative disorders (LDs) are a heterogeneous group of at least 70 conditions that result from the clonal proliferation of B, T, and NK cells. Inflammatory bowel disease (IBD)-associated lymphomas are typically B-cell LD, while T-cell or Hodgkin's lymphomas are rare. In IBD patients not on immunosuppression, the risk of LD seems to be similar or slightly higher than the background population risk. Thiopurine therapy is associated with an increased risk: the relative risk is increased four- to sixfold and the absolute risk varies between 1 in 4000-5000 for those aged 20-29 to 1 in 300-400 in those over 70. It is difficult to quantify the risk of anti- tumor necrosis factor (TNF) therapy alone; however, it appears to be less than for thiopurines alone. There is particular concern regarding the development of post-transplant-like LD in those with latent epstein-barr virus (EBV) infection exposed to immunosuppressives, the occurrence of hepatosplenic T cell lymphoma in patients treated with combination anti-TNF and thiopurine therapy, and the development of hemophagocytic lymphohistiocytosis in those who acquire a primary EBV or other infections while on immunosuppressive medication. There are currently no guidelines for monitoring EBV (or other virus) status in patients on immunosuppression, although it could be used to monitor those who have a prior history of lymphoma and are about to start a thiopurine or anti-TNF agent. In discussing the risks of lymphoproliferative disorders associated with agents used for the treatment of IBD, patients can often be reassured that the benefits of such therapy still outweigh the small, but real, risks.

Transient immunosuppression: a bridge between infection and the atypical autoimmunity of Guillain-Barré syndrome?

Guillain-Barré syndrome (GBS) is an acute, usually monophasic, disorder of the peripheral nervous system that is assumed to be of immune-mediated pathogenesis. However, several clinical features and experimental findings of GBS are uncharacteristic for an immune-mediated disorder and set this condition apart from other disorders with a putative immune-mediated pathogenesis. These features include, among others, the monophasic nature of GBS, the lack of response to immunosuppressive (unlike immunomodulatory) therapy, the absence of a typical association with immunogenetic background and the inability to establish a valid and relevant animal model. We suggest a comprehensive hypothesis for the pathogenesis of GBS that is based on the assumption that the condition is due to a transient (or occasionally chronic) immune deficiency, as in most cases GBS follows an infection with pathogens known to induce immunosuppression. Such infections may be followed by breakdown of immune tolerance and induction of an immune attack on peripheral nerves. Mounting of the immune-mediated assault might be triggered either by the same infective pathogen or by secondary infection. Clearance of the infection and resumption of a normal immune response and tolerance eventually terminate the immune-mediated damage to the peripheral nerves and enable recovery. This hypothesis assumes that the entire sequence of events that culminates in GBS is due to transient exogenous factors and excludes a significant role for inherent host susceptibility, which explains the monophasic nature of the disorder.

Measurement of Epstein-Barr virus DNA load using a novel quantification standard containing two EBV DNA targets and SYBR Green I dye

Background

Reactivation of Epstein-Barr virus (EBV) infection may cause serious, life-threatening complications in immunocompromised individuals. EBV DNA is often detected in EBV-associated disease states, with viral load believed to be a reflection of virus activity. Two separate real-time quantitative polymerase chain reaction (QPCR) assays using SYBR Green I dye and a single quantification standard containing two EBV genes, Epstein-Barr nuclear antigen-1 (EBNA-1) and BamHI fragment H rightward open reading frame-1 (BHRF-1), were developed to detect and measure absolute EBV DNA load in patients with various EBV-associated diseases. EBV DNA loads and viral capsid antigen (VCA) IgG antibody titres were also quantified on a population sample.

Results

EBV DNA was measurable in ethylenediaminetetraacetic acid (EDTA) whole blood, peripheral blood mononuclear cells (PBMCs), plasma and cerebrospinal fluid (CSF) samples. EBV DNA loads were detectable from 8.0 × 10² to 1.3 × 10⁸ copies/ml in post-transplant lymphoproliferative disease (n = 5), 1.5 × 10³ to 2.0 × 10⁵ copies/ml in infectious mononucleosis (n = 7), 7.5 × 10⁴ to 1.1 × 10⁵ copies/ml in EBV-associated haemophagocytic syndrome (n = 1), 2.0 × 10² to 5.6 × 10³ copies/ml in HIV-infected patients (n = 12), and 2.0 × 10² to 9.1 × 10⁴ copies/ml in the population sample (n = 218). EBNA-1 and BHRF-1 DNA were detected in 11.0% and 21.6% of the population sample respectively. There was a modest correlation between VCA IgG antibody titre and BHRF-1 DNA load (rho = 0.13, p = 0.05) but not EBNA-1 DNA load (rho = 0.11, p = 0.11).

Conclusion

Two sensitive and specific real-time PCR assays using SYBR Green I dye and a single quantification standard containing two EBV DNA targets, were developed for the detection and measurement of EBV DNA load in a variety of clinical samples. These assays have application in the investigation of EBV-related illnesses in immunocompromised individuals.

Infection of T lymphocytes in Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis in children of non-Asian origin

BACKGROUND

Epstein-Barr virus (EBV) is one of the most frequent triggers of hemophagocytic lymphohistiocytosis (HLH). EBV-associated HLH (EBV-HLH) and ectopic infection of T cells has been particularly described in patients from Far East Asia.

PROCEDURE

In a cohort of 12 children with EBV-HLH treated in Germany, the EB viral load was detected by real-time polymerase chain reaction in plasma and peripheral blood mononuclear cells (PBMC). Virological and clinical data were analyzed retrospectively.

RESULTS

Among the 12 mainly German patients, children with underlying immunodeficiencies as well as otherwise healthy individuals were affected. The clinical course ranged from a steroid-responding to a fatal disease despite intensive treatment. Increased EBV copy numbers in plasma and/or PBMC were found in all patients. Serial measurements reflected the course of the disease. Cell-type specific viral load was determined in seven patients and revealed EBV-infection of T cells in all of them. In contrast to the reported Asian patients a significant viral load was also found in B cells.

CONCLUSIONS

T cell infection appears to be a typical feature of EBV-associated HLH irrespective of patients ethnic background and the clinical course. Evaluation of cell-type specific infection should be considered when targeted therapy is applied.

Fatal Epstein-Barr virus primo infection in a 25-year-old man treated with azathioprine for Crohn's disease

We report a case of Epstein-Barr virus (EBV) primo infection with the development of successive infectious mononucleosis, hemophagocytic lymphohistiocytosis, and B-cell lymphoproliferative disorder in a patient treated with azathioprine for Crohn's disease. This case report suggests that specific EBV-related clinical and virological management should be considered when treating a patient with inflammatory bowel disease with azathioprine.

Evaluation of the Epstein-Barr virus R-gene quantification kit in whole blood with different extraction methods and PCR platforms

Reliable real-time quantitative PCR assays to measure Epstein-Barr virus (EBV) DNA load (EBV) are useful for monitoring EBV-associated diseases. We evaluated a new commercial kit, EBV R-gene Quantification kit (Argene, Varilhes, France) to quantify EBV DNA load in whole blood. Assay performance was assessed with two PCR platforms (LightCycler 2.0 and SmartCycler 2.0) and three commercial DNA extraction methods. The assay was compared with our in-house real-time EBV PCR using samples from the Quality Control for Molecular Diagnostics 2006 EBV proficiency program and using 167 whole-blood specimens from individuals with infectious mononucleosis, from transplanted or HIV-infected patients, and from EBV-seropositive healthy carriers. The EBV R-gene assay was sensitive to 500 copies of EBV DNA per milliliter of whole blood with the two PCR platforms and the three extraction methods and was linear across 4 orders of magnitude. Intra- and interassay coefficients of variations were less than 20%. Nine of 10 samples tested with the EBV R-gene were in agreement with the expected qualitative results of the Quality Control for Molecular Diagnostics 2006 EBV proficiency program, and 7 of 10 samples were within +/-0.5 log units of the expected quantitative values, with discrepant results mostly observed for low viral load (ie, <1000 copies/ml). In the clinical specimens, the correlation between the R-gene assay and the in-house PCR was high (r=0.92). In conclusion, the EBV R-gene assay accurately assesses the EBV DNA load in whole blood of patients with various forms of EBV infections.

Assessment of automated DNA extraction coupled with real-time PCR for measuring Epstein-Barr virus load in whole blood, peripheral mononuclear cells and plasma

BACKGROUND

Epstein-Barr virus (EBV) DNA load monitoring in blood has been shown to be essential for the diagnosis of EBV-associated diseases. However, the methods currently used to assess EBV DNA load are often time-consuming and require prior blood separation.

OBJECTIVES

The aim of this study was to evaluate the relative diagnostic value of EBV DNA load monitoring in whole blood, peripheral blood mononuclear cells (PBMCs) and plasma after automated DNA extraction using the MagNA Pure extractor followed by LightCycler real-time quantitative PCR (LC-PCR).

STUDY DESIGN

First, EBV DNA load was assessed retrospectively after automated or manual extraction on 104 PBMC specimens. Second, EBV DNA load was determined prospectively with the automated extraction procedure in the whole blood, PBMCs and plasma of 100 samples from patients with EBV-related diseases (group 1, n = 20), HIV-seropositive individuals (group 2, n = 66), and healthy EBV carriers (group 3, n = 14).

RESULTS

A good correlation was observed between automated and manual extraction on 104 PBMC specimens (r = 0.956; P < 0.0001). In the prospective study, 67 samples were positive in both whole blood and PBMCs, with a good correlation between EBV DNA loads in whole blood and PBMCs (r = 0.936; P < 0.0001). Only 18/100 samples were positive in plasma. Higher viral loads were regularly observed in the three blood compartments from group 1 than from groups 2 and 3.

CONCLUSION

This study demonstrated that an automated extraction of EBV DNA is easier to perform in whole blood or plasma than in PBMCs and facilitates the standardisation of EBV DNA measurement by real-time quantitative PCR. The quantitative detection of EBV DNA load in whole blood appeared more sensitive than in plasma for infectious mononucleosis in immunocompetent patients, probably because of a rapid loss of plasmatic EBV DNA. In transplant patients, EBV DNA load monitoring in whole blood and in plasma turned out to be equivalent in terms of feasibility and accuracy for the early diagnosis of post-transplant lymphoproliferative diseases (PTLDs).

Virologic Diagnosis, Viral Monitoring, and Treatment of Epstein-Barr Virus Infectious Mononucleosis

Epstein-Barr virus (EBV) is the cause of infectious mononucleosis and is associated with severe infections in immunocompromised patients. EBV is also causally linked with several human malignancies. The heterophile antibody test and EBV-specific antibody tests remain the principal means of diagnosis of initial infection in otherwise healthy patients. Enzyme-linked immunosorbent assays have replaced the traditional immunofluorescence assays for EBV-specific antibodies. Several newer molecular diagnostic tests have become available that facilitate accurate monitoring of infection. The role of these tests for patients with uncomplicated infectious mononucleosis is limited, although these tests are being increasingly used to monitor the state and level of EBV replication for severe infections and among immunocompromised patients. Antiviral therapy has a limited, short-term effect on oropharyngeal shedding but has proven ineffective for the clinical manifestations of infectious mononucleosis. Patients with selected complications frequently benefit from short-term corticosteroid therapy.

Remission of HHV-8 and HIV-associated multicentric Castleman disease with ganciclovir treatment

Multicentric Castleman disease (MCD) is a lymphoproliferative disorder associated with human herpesvirus 8 (HHV-8) infection among persons with human immunodeficiency virus (HIV) infection. Treatment often includes chemotherapy, and progression to non-Hodgkin lymphoma frequently occurs. MCD is characterized in part by active HHV-8 replication, and many of the symptoms of MCD may be attributable to viral gene products. We describe the effect of ganciclovir on the clinical and virologic course of MCD in a series of 3 case reports. Two patients experienced a reduction in the frequency of episodic flares of MCD and detectable HHV-8 DNA with intravenous or oral ganciclovir, whereas the third patient recovered from an acute episode of renal and respiratory failure with intravenous ganciclovir therapy. These data provide in vivo evidence for the utility of antiviral agents against HHV-8 in the management of MCD.

Acute Respiratory Failure and Cerebral Hemorrhage due to Primary Epstein-Barr Virus Infection

Epstein-Barr virus (EBV) is a ubiquitous human herpesvirus with worldwide distribution. Primary infection with EBV occurs early in life and typically presents as infectious mononucleosis. The usual course of the disease is benign and most patients recover uneventfully. Severe infections are reported particularly in immunocompromised patients. Mild, asymptomatic pneumonitis is reported in about 5-10% of cases of infectious mononucleosis, but severe pneumonitis with hypoxemia is very rare in immunocompetent individuals. We report a young female adolescent in whom an acute EBV infection led to severe bilateral pneumonitis, a systemic inflammatory response and intracerebral bleeding. The clinical course and results of quantitative viral DNA determinations in plasma are presented.

Clinical evaluation of a quantitative real time polymerase chain reaction assay for diagnosis of primary Epstein-Barr virus infection in children

BACKGROUND

Epstein-Barr virus (EBV) infectious mononucleosis is often diagnosed based on characteristic clinical features and either a positive heterophil antibody test or serology, both of which can be unreliable in young children. Real time quantitative PCR assays that measure EBV DNA load in serum or plasma are highly sensitive in young children, but serum and plasma contain inhibitors of PCR which must be removed by DNA extraction techniques. A real time TaqMan PCR assay was designed and evaluated for simultaneously measuring EBV DNA load and validating the removal of PCR inhibitors from serum samples.

METHODS

A serum sample was available from patients classified serologically as primary EBV infection (n = 28), EBV-seronegative (n = 25) and EBV-seropositive (n = 26). Patients were classified as having EBV infectious mononucleosis if they had specified clinical findings and > or =10% atypical lymphocytes in peripheral blood or had a positive Monospot test result. DNA was purified by a spin column method and tested in PCR reactions with primers for EBV DNA polymerase gene and internal control targets. Amplification of the two PCR products was measured in real time with separate TaqMan DNA probes labeled with various fluorescent reporters.

RESULTS

The mean age of study patients was 9 years, 4 months. Twenty-one (75%) of the patients in the primary EBV infection group, one (4%) of the seronegatives and none of the seropositives had detectable EBV DNA. Within the primary infection group, those with detectable virus were more likely than those without detectable virus to have evidence of lymphadenopathy (14 of 16 vs.1 of 5; P = 0.011), higher mean atypical (11.7 vs.0.9%; P = 0.002) and absolute atypical (1.5 vs.0.1 x 109/l; P = 0.004) lymphocyte count, higher mean absolute lymphocyte count (4.7 vs.2.3 x 109/l; P = 0.026) and higher mean aspartate aminotransferase value (119.8 vs.37.3 IU/l; P = 0.036). Ten patients, all in the primary infection group, had EBV infectious mononucleosis, and all had positive PCR results. No sample contained PCR inhibitors.

CONCLUSIONS

A real time TaqMan PCR assay allows rapid identification of patients with primary EBV infection and those with EBV infectious mononucleosis.

Treatment of Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH) in young adults: a report from the HLH study center

BACKGROUND

Epstein-Barr virus-associated hemophagocytic lymphohistiocytosis (EBV-HLH), also known as EBV-associated hemophagocytic syndrome, develops mostly in children and young adults and may be fatal. Early etoposide treatment has been confirmed to be effective in children. However, it is unclear whether the same treatment is useful in adults.

PROCEDURE

To assess whether etoposide is effective in treating young adult cases, we retrospectively studied the therapeutic measures taken and outcomes in 20 young adult cases of EBV-HLH. Eleven cases were registered in our HLH study center in Kyoto and nine derived from the literature. The patients were between 17 and 33 years old and eight were males. The influence of gender, cell lineage (T- or natural killer-), EBV serology pattern, jaundice and treatment on the outcome was assessed.

RESULTS AND CONCLUSIONS

Patients receiving etoposide within four weeks after diagnosis had a good prognosis as five of the seven patients survived compared to one of 13 not treated with etoposide or treated late (chi-square test for survival, P = 0.0095). The Kaplan-Meier analysis showed the 2.5-year survival of 85.7 +/- 13.2% in the early etoposide-treated patients, compared to 10.3 +/- 9.4% in the remaining patients (log-rank test, P = 0.0141). Thus, early etoposide treatment is effective in treating EBV-HLH in young adults as well as in children.

Rabbit model for human EBV-associated hemophagocytic syndrome (HPS): sequential autopsy analysis and characterization of IL-2-dependent cell lines established from herpesvirus papio-induced fatal rabbit lymphoproliferative diseases with HPS

Epstein-Barr virus-associated hemophagocytic syndrome (EBV-AHS) is often associated with fatal infectious mononucleosis or T-cell lymphoproliferative diseases (LPD). To elucidate the true nature of fatal LPD observed in Herpesvirus papio (HVP)-induced rabbit hemophagocytosis, reactive or neoplastic, we analyzed sequential development of HVP-induced rabbit LPD and their cell lines. All of the seven Japanese White rabbits inoculated intravenously with HVP died of fatal LPD 18 to 27 days after inoculation. LPD was also accompanied by hemophagocytic syndrome (HPS) in five of these seven rabbits. Sequential autopsy revealed splenomegaly and swollen lymph nodes, often accompanied by bleeding, which developed in the last week. Atypical lymphoid cells infiltrated many organs with a "starry sky" pattern, frequently involving the spleen, lymph nodes, and liver. HVP-small RNA-1 expression in these lymphoid cells was clearly demonstrated by a newly developed in situ hybridization (ISH) system. HVP-ISH of immunomagnetically purified lymphoid cells from spleen or lymph nodes revealed HVP-EBER1+ cells in each CD4+, CD8+, or CD79a+ fraction. Hemophagocytic histiocytosis was observed in the lymph nodes, spleen, bone marrow, and thymus. HVP-DNA was detected in the tissues and peripheral blood from the infected rabbits by PCR or Southern blot analysis. Clonality analysis of HVP-induced LPD by Southern blotting with TCR gene probe revealed polyclonal bands, suggesting polyclonal proliferation. Six IL-2-dependent rabbit T-cell lines were established from transplanted scid mouse tumors from LPD. These showed latency type I/II HVP infection and had normal karyotypes except for one line, and three of them showed tumorigenicity in nude mice. These data suggest that HVP-induced fatal LPD in rabbits is reactive polyclonally in nature.