Cytomegalovirus shedding in the oral cavity of allogeneic haematopoietic stem cell transplant patients

Intraoral human herpes viruses detectable by PCR in majority of patients

OBJECTIVES

To identify factors which influence the intraoral prevalence of human herpes viruses (HHVs) using mucosal swabs, saliva samples and qPCR analysis.

METHODOLOGY

In this cross-sectional observational study, matched saliva and oral swabs were collected from a total of 115 subjects: 70 immunocompetent subjects with no mucosal abnormalities, 22 with mucosal abnormalities and 23 therapeutically immunocompromised individuals. Extracted DNA was analysed by multiplex qPCR for detection and quantification of HHVs 1-6.

RESULTS

At least one human herpes virus was detected in 77.1% of immunocompetent individuals with no mucosal abnormalities, with EBV the most commonly detected at 61.4%. HHV-6 was detected in 17.1%, HSV-1 in 4.3% and CMV in 1.1%. Detection was higher in saliva than in oral swabs. There was no detection of HSV-2 or VZV. Neither presence of oral mucosal abnormality nor therapeutic immunocompromise was related to increased detection of human herpes virus.

CONCLUSION

Commensal detection rates of EBV are high, and caution in clinical correlation of positive detection is warranted. Commensal CMV rates are low, and detection is likely to be clinically relevant. This study presents a comprehensive commensal detection rate of HHVs 1-6 by qPCR in saliva and swabs.

Incidental mucocutaneous cytomegalovirus detection and its predictive value for systemic disease

Multiplex polymerase chain reaction (PCR) testing has revolutionised microbiological practice but also increased the number of positive results of uncertain significance. This phenomenon has been seen in the increasing detection of cytomegalovirus (CMV) in mucocutaneous swabs for herpesviruses, the microbiological significance of which is a priori unclear. The aim of our study was to determine if an incidental finding of a positive CMV result represented CMV disease, if it facilitated a timely diagnosis of CMV disease or whether there were any deleterious outcomes. We performed a retrospective review of patients with an incidentally positive PCR result for CMV on external and mucosal swabs, including medical comorbidities and presence of immunosuppression, subsequent investigations, whether a diagnosis of CMV disease was made, and treatment. CMV detection was infrequent, detected in 158 (3.4%) of 4626 herpes multiplex PCR tests performed. The majority (60.4%) of patients were immunocompromised, and amongst these patients a positive swab represented a new diagnosis or already known CMV disease in 14%. In seven patients (5%), all of whom were immunocompromised, the positive CMV PCR on a swab led to further investigation and subsequent diagnosis and treatment of CMV disease. Whilst not recommended for diagnosis of CMV disease, if CMV is detected on a mucocutaneous swab in an immunocompromised patient, further assessment and investigation for CMV disease should be undertaken.

Urinary Cytomegalovirus Shedding in the United States: The National Health and Nutrition Examination Surveys, 1999-2004

Background

There are no data on the prevalence of cytomegalovirus (CMV) shedding from a representative sample of the US population. This information is critical for understanding and preventing CMV.

Methods

We tested urine specimens from CMV immunoglobulin (Ig) G-positive participants aged 6-49 years in 3 racial/ethnic groups from the National Health and Nutrition Examination Surveys 1999-2004 for the presence of CMV DNA using real-time polymerase chain reaction assay. We examined the association of sociodemographic characteristics with shedding prevalence and viral loads.

Results

Among 6828 CMV IgG-positive participants tested, 537 had CMV DNA detected in urine-a shedding prevalence of 9.70%. Among persons aged 6-49 years, shedding prevalence was 3.83%. The prevalence of urinary shedding was inversely associated with increasing age (26.60%, 6.50%, and 3.45% in CMV IgG-positive participants aged 6-11, 12-19, and 20-49 years, respectively; P < .001 for trend test and pairwise comparisons). Urinary viral load also decreased significantly with age (mean, 2.97, 2.69, and 2.43 log10 copies/mL in those age groups, respectively; P < .001 for trend test and pairwise comparisons).

Conclusions

Urinary CMV shedding and viral loads decreased dramatically with age, likely reflecting higher rates of primary CMV infection and longer duration of shedding in younger individuals. The findings demonstrate that children aged 6-11 years continue to shed CMV at higher rates and viral loads than adolescents and adults and thus may still be an important source for CMV transmission.

Monitoring of oral cytomegalovirus DNA shedding for the prediction of viral DNAemia in allogeneic hematopoietic stem cell transplant recipients

Preemptive antiviral therapy based on detecting cytomegalovirus (CMV) DNAemia above a preestablished threshold is the mainstay strategy for the prevention of CMV disease in allogeneic hematopoietic stem cell transplant (allo-HSCT) recipients; nevertheless, CMV DNAemia, even at low levels, may increase mortality. We investigated whether surveillance of saliva for the presence of CMV DNA may anticipate the occurrence of CMV DNAemia. This was a prospective observational study with 53 consecutively enrolled allo-HSCT recipients. Saliva and plasma specimens were collected on a weekly basis from Day 0 to Day 100 after transplantation. CMV DNA was quantified in both specimen types using the Abbott Real-Time PCR assay (Abbott Molecular, Des Plaines, IL). CMV DNA was quantifiable in 44 (83%) patients: either in saliva (n = 1) or plasma (n = 12) only, or in both specimen types (n = 31). CMV oral shedding preceded the occurrence of CMV DNAemia in eight patients (18.2%), while the opposite pattern was observed in 21 patients (47.7%). The CMV DNA loads quantified in saliva and plasma correlated modestly (P = 0.33; P = 0.013) and did not differ in magnitude (P = 0.527). No transplantation factors, other than recipient CMV seropositivity, were associated with oral CMV DNA shedding; serum CMV IgG levels were comparable, regardless of the timing of the detection of CMV DNA at both sites. In summary, screening of saliva specimens for the presence of CMV DNA appear to be of limited value for anticipating the occurrence of CMV DNAemia in allo-HSCT recipients.

Shedding of HSV-1, HSV-2, CMV, and EBV in the saliva of hematopoietic stem cell transplant recipients at Fundación HOMI - Hospital de la Misericordia, Bogotá, D.C

INTRODUCTION

Hematopoietic stem cell transplantation in pediatric patients is an alternative treatment for different diseases. The conditioning regimen for transplant predisposes recipients to the development of infections. Viral infections by herpes simplex virus 1 (HSV-1), herpes simplex virus 2 (HSV-2), human cytomegalovirus (CMV), and Epstein-Barr virus (EBV), are the most common, and the leading cause of morbidity and mortality among these patients. These viruses lie dormant in various cell types and the reactivation of latent infections may lead to asymptomatic viral shedding in saliva. The detection of these viruses in secretions may contribute to understand the behavioral dynamics of these viral infections in transplanted patients, and to the early diagnosis of reactivation. 

OBJECTIVE

To assess HSV-1, HSV-2, CMV and EBV viral shedding in the saliva of patients admitted for hematopoietic stem cell transplantation at Fundación HOMI - Hospital de la Misericordia between January and November of 2012. 

MATERIALS AND METHODS

We evaluated stimulated saliva samples of 17 hematopoietic stem cell transplantation recipients weekly. We performed DNA extraction from saliva, and we evaluated the presence of DNA for HSV-1, HSV-2, CMV, and EBV by PCR. 

RESULTS

While we detected HSV-2 and CMV DNA in the saliva of four patients, EBV DNA was detected in nine patients with leukopenia. In contrast, we did not detect HSV-1 DNA in saliva. Additionally, four out of the 17 patients showed a simultaneous shedding of CMV and EBV. 

CONCLUSIONS

By conventional PCR, we demonstrated asymptomatic HSV-2, CMV, and EBV viral shedding in saliva, associated with leukopenia.

Prevalence of oral mucosal lesions in a brazilian military police population

BACKGROUND

Data obtained from oral health surveys are very important for identifying disease-susceptible groups and for developing dental care and prevention programs. So, the purpose of the current article was to investigate the prevalence of oral mucosa lesions (OMLs) in a population of Brazilian police.

MATERIAL AND METHODS

Interviews and oral cavity examinations were performed on a sample of 395 police officers who were randomly selected by the calibrated researcher. The number of individuals was obtained by a sample calculation using the finite population correction. The diagnostic criteria were based on the WHO (1997) criteria and adapted to Brazilian surveys.

RESULTS

In total, 8.61% of the population presented some OML. Traumatic injuries and benign migratory glossitis (BMG) were the most prevalent lesions.

CONCLUSIONS

The prevalence of potentially malignant disorders was lower than among the Brazilian population.The most prevalent lesion among the police officers was related to trauma. Patients dissatisfied with oral health had a higher risk of presenting OMLs. Key words:Mouth disease, mouth mucosa, military personnel, public health, oral pathology, oral leukoplakia.

Human cytomegalovirus tropism for mucosal myeloid dendritic cells

Human CMV infections are a serious source of morbidity and mortality for immunocompromised patients and for the developing fetus. Because of this, the development of new strategies to prevent CMV acquisition and transmission is a top priority. Myeloid dendritic cells (DC) residing in the oral and nasal mucosae are among the first immune cells to encounter CMV during entry and greatly contribute to virus dissemination, reactivation from latency, and horizontal spread. Albeit affected by the immunoevasive tactics of CMV, mucosal DC remain potent inducers of cellular and humoral immune responses against this virus. Their natural functions could thus be exploited to generate long-lasting protective immunity against CMV by vaccination via the oronasal mucosae. Although related, epithelial Langerhans-type DC and dermal monocyte-derived DC interact with CMV in dramatically different ways. Whereas immature monocyte-derived DC are fully permissive to infection, for instance, immature Langerhans-type DC are completely resistant. Understanding these differences is essential to design innovative vaccines and new antiviral compounds to protect these cells from CMV infection in vivo.

Saliva as a diagnostic fluid. Literature review

There is a growing interest in diagnosis based on the analysis of saliva. This is a simple, non-invasive method of obtaining oral samples which is safe for both the health worker and the patient, not to mention allowing for simple and cost-efficient storage. The majority of studies use general saliva samples in their entirety, complex fluids containing both local and systemic sources and whose composition corresponds to that of the blood. General saliva contains a considerable amount of desquamated epithelial cells, microorganisms and remnants of food and drink; it is essential to cleanse and refine the saliva samples to remove any external elements. Immediate processing of the sample is recommended in order to avoid decomposition, where this is not possible, the sample may be stored at -80ºC. Salivary analysis – much the same as blood analysis – aims to identify diverse medication or indications of certain diseases while providing a relatively simple tool for both early diagnosis and monitoring various irregularities. The practicalities of salivary analysis have been studied in fields such as: viral and bacterial infections, autoimmune diseases (like Sjögren’s syndrome and cɶliac disease), endocrinopathies (such as Cushing’s syndrome), oncology (early diagnosis of breast, lung and stomach carcinoma and oral squamous cell carcinoma), stress assessment, medication detection and forensic science among others. It is hoped that salivary analysis, with the help of current technological advances, will be valued much more highly in the near future. There still remain contradictory results with respect to analytic markers, which is why further studies into wider-ranging samples are fundamental to prove its viability.

Key words:Saliva, biomarkers, early diagnosis.

Efficiency and risk factors for CMV transmission in seronegative hematopoietic stem cell recipients

Cytomegalovirus (CMV) transmission via stem cells or marrow in CMV donor seropositive/recipient seronegative (D+/R-) hematopoietic cell transplantation (HCT) is surprisingly inefficient, and factors associated with transmission in these high-risk HCT recipients are unknown. In a retrospective cohort of D+/R- HCT recipients, cumulative incidence curve estimates were used to determine posttransplantation rates of CMV and multivariable Cox proportional models to assess risk factors associated with transmission. A total of 447 patients from 1995 to 2007 were eligible for enrollment. Overall, 85 of 447 (19.0%) acquired CMV at a median of 49 days (IQR 41-60) posttransplantation. CMV disease before day 100 occurred in 6 of 447 (1.3%) patients and in 7 of 447 (1.6%) after day 100. The donor graft, specifically the total nucleated cell count (adjusted hazard ratio [HR] 2.7; 95% confidence interval [CI], 1.4-4.7, P = .0002), was the only factor associated with CMV transmission in multivariable analyses. Notably, the source stem cells (marrow versus peripheral blood stem cell [PBSC]), screening method, and graft-versus-host disease (GVHD) were not associated with transmission. Thus, a highly cellular graft was the only identifiable risk factor associated with CMV transmission, suggesting that viral genomic content of the donor graft determines transmission efficiency in D+/R- HCT recipients.

Small molecule inhibitors of the host cell COX/AREG/EGFR/ERK pathway attenuate cytomegalovirus-induced pathogenesis

As with other herpesviruses, human cytomegalovirus (hCMV) has the ability to establish lifelong persistence and latent infection following primary exposure, salivary glands (SMGs) being the primary site of both. In the immunocompromised patient, hCMV is a common cause of opportunistic infections, and subsequent morbidity and mortality. Elucidating the molecular pathogenesis of CMV-induced disease is critical to the development of more effective and safer drug therapies. In the present study, we used a novel mouse postnatal SMG organ culture model of mCMV-induced dysplasia to investigate a candidate signaling network suggested by our prior studies (COX-2/AREG/EGFR/ERK). The objective was to employ small molecule inhibitors to target several key steps in the autocrine loop, and in this way ameliorate pathology. Our results indicate that upregulation of ERK phosphorylation is necessary for initial mCMV-induced pathogenesis, and that ErbB receptor family phosphorylation and downstream signaling are highly relevant targets for drug discovery.

HCMV gB genotype and its association with cytokine levels in hematopoietic stem cell transplantation

BACKGROUND

Glycoprotein B (gB) has been implicated in determining the pathogenicity and clinical outcomes of human cytomegalovirus (HCMV) disease.

OBJECTIVE

The purpose of this study was to assess the prevalence of gB genotypes in allogeneic hematopoietic stem cell transplantation (allo-HSCT) and the relationship between it and cytokine levels in saliva and blood samples. The impact of these parameters on patients' survival was also investigated.

METHODS

Samples were obtained from 63 patients receiving an allo-HSCT. HCMV gB genotyping was carried out by multiplex nested PCR. The cytokine levels were assessed using ELISA assay.

RESULTS

A single or mixed genotype infection was detected in the saliva and blood of 36/63 and 52/63 subjects, respectively. Patients with gB2 in their saliva showed lower IL-10 levels in comparison with patients without gB2. Reduced blood levels of IFN-γ and IL-1β were also found in recipients with the HCMV gB4 genotype compared with patients without it. Decreased IL-1β and increased IL-10 blood levels were associated with lower survival. However, HCMV gB genotypes have no impact on patient outcome.

CONCLUSION

Decreased IL-1β and increased IL-10 levels in the blood are associated with lower survival. HCMV genotypes are associated with different cytokine levels in saliva and blood.

Detection of human cytomegalovirus in bronchoalveolar lavage fluid of lung transplant recipients reflects local virus replication and not contamination from the throat

Whether bronchoalveolar lavage (BAL) fluid may be contaminated with oropharyngeal cytomegalovirus (CMV) has never been investigated. In an analysis of CMV DNA loads in 76 simultaneously obtained BAL fluid and throat wash samples from lung transplant recipients, we show that such contamination is unlikely and that detection of CMV DNA in BAL fluid reflects virus replication in the lung.

Saliva as a source of HCMV DNA in allogeneic stem cell transplantation patients

OBJECTIVE

The purpose of this study was to investigate the use of saliva for the identification of human cytomegalovirus (HCMV) in allogeneic hematopoietic stem cell transplant patients by real time PCR compared with blood.

MATERIALS AND METHODS

Saliva and blood samples were sampled weekly in 30 allogeneic hematopoietic stem cell transplant patients until 100 days after transplant. Total genomic DNA, extracted from saliva and whole-blood samples, was used for HCMV real time PCR. Nonparametric tests were performed, and P value <or=0.05 was considered statistically significant.

RESULTS

Human cytomegalovirus DNA load in saliva showed a high correlation with viral DNA in the blood (R = 0.858; P < 0.0001). Blood DNA levels also correlated with HCMV antigenemia (R = 0.773; P < 0.0001). The HCMV levels in saliva (P = 0.015) and blood (P = 0.008) showed higher levels at the beginning of antiviral treatment, with clear reduction after this period. Saliva showed earlier HCMV reactivation than blood detected by real time PCR and antigenemia assay in 11 out of 22 subjects.

CONCLUSIONS

This study shows that the real time PCR test could be useful to identify HCMV DNA in saliva and to monitor patients at risk of cytomegalovirus disease after allogeneic hematopoietic stem cell transplant. However, further studies are necessary to confirm this data.

Usefulness of oral cytopathology in the diagnosis of infectious diseases

In recent years, the incidence of oral opportunistic infections has increased, partly due to the widespread implementation of organ and bone marrow transplantation and the increase in the prevalence of human immunodeficiency virus (HIV) infection. Cytology can be used as a rapid, inexpensive and simple routine procedure in diagnosing infectious diseases of the mouth. Moreover, ancillary methods can be applied to cytological samples, increasing the specificity and sensitivity for the diagnosis of infectious diseases. This review describes the cytopathological features of the main viral, fungal, bacterial and parasitic infections of the mouth. Cytological techniques of specimen collection, identification of infectious agents by cytomorphological approaches and ancillary methods, and diagnostic pitfalls will be discussed.

Persistent gammaherpesvirus replication and dynamic interaction with the host in vivo

Gammaherpesviruses establish life-long persistency inside the host and cause various diseases during their persistent infection. However, the systemic interaction between the virus and host in vivo has not been studied in individual hosts continuously, although such information can be crucial to control the persistent infection of the gammaherpesviruses. For the noninvasive and continuous monitoring of the interaction between gammaherpesvirus and the host, a recombinant murine gammaherpesvirus 68 (MHV-68, a gammaherpesvirus 68) was constructed to express a firefly luciferase gene driven by the viral M3 promoter (M3FL). Real-time monitoring of M3FL infection revealed novel sites of viral replication, such as salivary glands, as well as acute replication in the nose and the lung and progression to the spleen. Continuous monitoring of M3FL infection in individual mice demonstrated the various kinetics of transition to different organs and local clearance, rather than systemically synchronized clearance. Moreover, in vivo spontaneous reactivation of M3FL from latency was detected after the initial clearance of acute infection and can be induced upon treatment with either a proteasome inhibitor Velcade or an immunosuppressant cyclosporine A. Taken together, our results demonstrate that the in vivo replication and reactivation of gammaherpesvirus are dynamically controlled by the locally defined interaction between the virus and the host immune system and that bioluminescence imaging can be successfully used for the real-time monitoring of this dynamic interaction of MHV-68 with its host in vivo.

The salivary glands as a privileged site of cytomegalovirus immune evasion and persistence

The salivary glands (SG) provide a haven for persistent cytomegalovirus replication, and in this regard are a privileged site of virus immune evasion. The murine cytomegalovirus (MCMV) model has provided insight into the immunological environment of the SG and the unqiue virus-host relationship of this organ. In response to MCMV infection, a robust T cell-mediated immune response is elicited, comprised predominantly of CD8+ T cells that phenotypically and functionally appear activated. However, they fail to clear virus by an unknown evasion mechanism that is independent of inhibitory NKG2A- or Programmed Death 1-mediated signaling. Virus is eventually eliminated from the SG by effector CD4+ T cells expressing antiviral cytokines. However, this mechanism is severely dampened by high levels of the immunosuppressive cytokine IL-10, selectively expressed by SG CD4+ T cells.