Distribution characteristics of human herpes viruses in the lower respiratory tract and their impact on 30-day mortality in community-acquired pneumonia patients.

Human herpes viruses (HHVs) are commonly detected in community-acquired pneumonia (CAP) patients, particularly those with complex complications, attracting increased attention from clinical practitioners. However, the significance of detecting HHVs in bronchoalveolar lavage fluid (BALF) with CAP patients is still unclear. This study retrospectively analyzed BALF samples from 64 CAP patients at the Kunming Third People's Hospital between August 2021 and December 2023. Metagenomic next generation sequencing (mNGS) was conducted on BALF samples during CAP onset. Multivariate Cox regression models were used to identify independent risk factors for 30-day all-cause mortality in CAP. HHVs were found in 84.4% of CAP patients, which were the most common pathogens (45.1%), followed by bacteria (30.2%) and fungi (11.5%). Bacterial-viral co-infections were most common, occurring in 39 patients. Notably, there was no significant difference in HHV presence between severe and non-severe CAP patients (EBV: P = 0.431, CMV: P = 0.825), except for HHV-7 (P = 0.025). In addition, there was no significant difference in the 30-day mortality between HHV positive and HHV negative groups (P = 0.470), as well as between the HHV-7 positive and HHV-7 negative groups (P = 0.910). However, neither HHVs nor HHV-7 was independent risk factors for 30-day mortality in CAP patients (HHVs: HR 1.171, P = 0.888; HHV-7: HR 1.947, P = 0.382). In summary, among the prevalent presence of multiple HHVs, EBV and CMV were the most prevalent in CAP patients. Patients with sCAP were more susceptible to HHV-7 than those with non-sCAP. These results provide valuable insights for clinicians in guiding appropriate interventions for CAP treatment.

Evaluation of the AltoStar AM16 system for the quantitation of AdV, CMV and HHV-6 DNA from clinical specimens.

The vulnerability of immunocompromised patients to common or opportunistic viral infections is particularly high. The quantitation of viral load in clinical specimens is important for the diagnosis and management of the infection and reactivation in this patient population, particularly transplant recipients. As the new regulation "IVDR" regarding in vitro diagnosis methods is about to come into effect in France, diagnostic laboratories have to implement methods and systems compatible with this new regulation. Technical performance of the AltoStar® Adenovirus (AdV), Cytomegalovirus (CMV) and human Herpesvirus-6 (HHV-6) DNA PCR Kits 1.5 was assessed on the AltoStar Automation system AM16 using reference kits in 146 clinical samples. Overall agreement in clinical specimens was 87.5 % (28/32), 96.8 % (62/64), 100 % (22/22), 100 % (28/28) and 92.8 % (26/28) for AdV, CMV (WB samples and other matrices), HHV-6 A&B respectively. Quantitative results were highly correlated and estimated to be equivalent within a 0.057-0.648 log-amount difference.We found that altona kits on The AltoStar AM16 system are suitable for clinical monitoring of AdV, CMV and HHV-6 in immunocompromised hosts.

HHV6-Associated Hydrocephalus in a Pediatric Hematopoietic Stem Cell Transplant Recipient: An Unusual Presentation.

Human herpesvirus 6 (HHV-6) is a widely spread DNA virus that is ubiquitous and persistent with primary infection occurring in early childhood, with reactivation of the infection a common phenomenon in severely immunocompromised hosts, including hematopoietic stem cell transplant (HSCT) patients, influencing morbidity and mortality. A wide spectrum of clinical presentations is reported in the literature with HHV-6 reactivation including post-transplant limbic encephalitis (PALE). We report the unusual case of a 6-year-old female 107 days postallogenic HSCT due to transfusion dependent beta thalassemia major who developed acute cerebellitis with secondary supratentorial hydrocephalus that required invasive surgical intervention. In addition to accompanying imaging findings, the patient tested positive for HHV-6 by PCR from both serum and CSF samples and demonstrated dramatic improvement with the institution of steroid therapy in addition to ganciclovir treatment. The availability of rapid diagnostic measures in addition to a multidisciplinary approach is crucial to manage HHV-6 encephalitis and associated complications in HSCT patients.

Human herpesvirus-6, HHV-8 and parvovirus B19 after allogeneic hematopoietic cell transplant: the lesser-known viral complications.

PURPOSE OF REVIEW: Viral infections continue to burden allogeneic hematopoietic cell transplant (HCT) recipients. We review the epidemiology, diagnosis, and management of human herpesvirus (HHV)-6, HHV-8 and parvovirus B19 following HCT. RECENT FINDINGS: Advances in HCT practices significantly improved outcomes but impact viral epidemiology: post-transplant cyclophosphamide for graft-versus-host disease prevention increases HHV-6 reactivation risk while the impact of letermovir for CMV prophylaxis - and resulting decrease in broad-spectrum antivirals - is more complex. Beyond the well established HHV-6 encephalitis, recent evidence implicates HHV-6 in pneumonitis. Novel less toxic therapeutic approaches (brincidofovir, virus-specific T-cells) may enable preventive strategies in the future. HHV-8 is the causal agent of Kaposi's sarcoma, which is only sporadically reported after HCT, but other manifestations are possible and not well elucidated. Parvovirus B19 can cause severe disease post-HCT, frequently manifesting with anemia, but can also be easily overlooked due to lack of routine screening and ambiguity of manifestations. SUMMARY: Studies should establish the contemporary epidemiology of HHV-6, and other more insidious viruses, such as HHV-8 and parvovirus B19 following HCT and should encompass novel cellular therapies. Standardized and readily available diagnostic methods are key to elucidate epidemiology and optimize preventive and therapeutic strategies to mitigate the burden of infection.

Viral myocarditis in combination with genetic cardiomyopathy as a cause of sudden death. An autopsy series.

Sudden cardiac death (SCD) is a major public health issue worldwide. In the young (< 40 years of age), genetic cardiomyopathies and viral myocarditis, sometimes in combination, are the most frequent, but underestimated, causes of SCD. Molecular autopsy is essential for prevention. Several studies have shown an association between genetic cardiomyopathies and viral myocarditis, which is probably underestimated due to insufficient post-mortem investigations. We report on four autopsy cases illustrating the pathogenesis of these combined pathologies. In two cases, a genetic hypertrophic cardiomyopathy was diagnosed in combination with Herpes Virus Type 6 (HHV6) and/or Parvovirus-B19 (PVB19) in the heart. In the third case, autopsy revealed a dilated cardiomyopathy and virological analyses revealed acute myocarditis caused by three viruses: PVB19, HHV6 and Epstein-Barr virus. Genetic analyses revealed a mutation in the gene coding for desmin. The fourth case illustrated a channelopathy and a PVB19/HHV6 coinfection. Our four cases illustrate the highly probable deleterious role of cardiotropic viruses in the occurrence of SCD in subjects with genetic cardiomyopathies. We discuss the pathogenetic link between viral myocarditis and genetic cardiomyopathy. Molecular autopsy is essential in prevention of these SCD, and a close collaboration between cardiologists, pathologists, microbiologists and geneticians is mandatory.

Human herpesvirus 6 reactivation and disease are infrequent in chimeric antigen receptor T-cell therapy recipients.

ABSTRACT: Human herpesvirus 6B (HHV-6B) reactivation and disease are increasingly reported after chimeric antigen receptor (CAR) T-cell therapy (CARTx). HHV-6 reactivation in the CAR T-cell product was recently reported, raising questions about product and patient management. Because of overlapping manifestations with immune effector cell-associated neurotoxicity syndrome, diagnosing HHV-6B encephalitis is challenging. We provide 2 lines of evidence assessing the incidence and outcomes of HHV-6B after CARTx. First, in a prospective study with weekly HHV-6B testing for up to 12 weeks after infusion, HHV-6B reactivation occurred in 8 of 89 participants; 3 had chromosomally integrated HHV-6 and were excluded, resulting in a cumulative incidence of HHV-6B reactivation of 6% (95% confidence interval [CI], 2.2-12.5). HHV-6B detection was low level (median peak, 435 copies per mL; interquartile range, 164-979) and did not require therapy. Second, we retrospectively analyzed HHV-6B detection in the blood and/or cerebrospinal fluid (CSF) within 12 weeks after infusion in CARTx recipients. Of 626 patients, 24 had symptom-driven plasma testing, with detection in 1. Among 34 patients with CSF HHV-6 testing, 1 patient had possible HHV-6 encephalitis for a cumulative incidence of 0.17% (95% CI, 0.02-0.94), although symptoms improved without treatment. Our data demonstrate that HHV-6B reactivation and disease are infrequent after CARTx. Routine HHV-6 monitoring is not warranted.

Performance evaluation of the SMG HHV-6 Q Real-Time PCR Kit for quantitative detection and differentiation of human herpesvirus 6A and 6B.

The aim of this study was to compare the performance of the newly developed SMG HHV-6 Q Real-Time PCR Kit (SMG assay) with the RealStar HHV-6 PCR Kit (RealStar assay). The analytical sensitivity and specificity, linearity, and precision of the SMG assay were evaluated. The clinical performance of the SMG assay was assessed and compared with that of the RealStar assay using 207 clinical specimens (HHV-6A positive, n = 51; HHV-6B positive, n = 64; HHV-6A/B negative, n = 92). The limit of detection of the SMG assay was 2.92 log10 copies/mL for HHV-6A DNA and 2.88 log10 copies/mL for HHV-6B DNA. The linear range was determined to be 3.40-9.00 log10 copies/mL for both viruses. Intra- and inter-assay variability were below 5% at concentrations ranging from 4 to 9 log10 copies/mL. No cross-reactivity was observed with the 25 microorganisms included in the specificity panel. The clinical sensitivity and specificity of the SMG and RealStar assays compared to in-house polymerase chain reaction and sequencing were as follows: SMG assay, 98.0% and 100% for HHV-6A DNA, respectively, and 96.9% and 100% for HHV-6B DNA, respectively; RealStar assay, 98.0% and 100% for HHV-6A DNA, respectively, and 90.6% and 100% for HHV-6B DNA, respectively. The correlation coefficients between viral loads measured by the two assays were 0.948 and 0.975, with mean differences of 0.62 and 0.32 log10 copies/mL for HHV-6A and HHV-6B DNA, respectively. These results demonstrate that the SMG assay is a sensitive and reliable tool for the quantitative detection and differentiation of HHV-6A and HHV-6B DNA.IMPORTANCEQuantitative real-time PCR (qPCR) that can distinguish between HHV-6A and HHV-6B DNA is recommended for diagnosis of active infection. The SMG HHV-6 Q Real-Time PCR Kit (SMG assay) is a newly developed qPCR assay that can differentiate between HHV-6A and HHV-6B DNA; however, little is known about its performance. In this study, we assessed the performance of the SMG assay and compared it with that of a commercially available qPCR assay, the RealStar HHV-6 PCR Kit (RealStar assay). The SMG assay demonstrated excellent analytical sensitivity and specificity, precision, and linearity. Furthermore, the viral loads measured by the SMG assay were highly correlated with those measured by the RealStar assay. Our results suggest that the SMG assay is a useful diagnostic tool for quantitative detection and differentiation of HHV-6A and HHV-6B DNA.

Metagenomic Next-Generation Sequencing (mNGS) of cerebrospinal fluid for diagnosis of human herpesvirus 6B encephalitis following transplantation for severe aplastic anemia.

INTRODUCTION: Human herpesvirus 6B (HHV-6B) encephalitis is common in immunosuppressed patients and presents a diagnostic challenge for physicians. Metagenomic next-generation sequencing (mNGS) may facilitate early diagnosis of HHV-6B encephalitis. Herein, we described a case of HHV-6B encephalitis following transplantation for severe aplastic anemia (SAA) diagnosed by mNGS. CASE SUMMARY: A 31-year-old male underwent myeloablative haploid hematopoietic stem cell transplantation for the treatment of SAA. On day + 21 after transplantation, the patient developed symptoms such as sudden epilepsy, drowsiness, memory dislocation, and memory loss. HHV-6B encephalitis was confirmed based on cranial MRI and mNGS of cerebrospinal fluid. Following antiviral therapy with sodium foscarnet, the symptoms improved and HHV-6B was negative by mNGS. There were no serious sequelae. Currently, the patient is in good health and is still under follow-up. CONCLUSIONS: A case of HHV-6B encephalitis after SAA transplantation was diagnosed by mNGS of cerebrospinal fluid in time and was effectively treated with sodium foscarnet.

Detection of HHV-6 Virus in specimen of a ductal pancreatic adenocarcinoma with comparison in tumor and normal tissue.

AIMS: The association of human herpesvirus 6 (HHV-6) species with pancreatic cancer is controversially discussed. The aim of this study was to further investigate the postulated association and to identify the basis of HHV-6 DNA positivity reported for pancreatic cancer tissue. METHODS: All samples of patients with pancreatic cancer (cancer and surrounding tissue) were analyzed for presence of HHV-6 DNA by PCR and then selected cases by immunohistochemistry. RESULTS: Sixty eight per cent (68% = 52/77) of all patients were HHV-6 DNA positive in any of the samples, 49% (38/77) were positive in tumor tissue. Specimens of just one patient were HHV-6A DNA positive, all other patients were positive for HHV-6B. Immunohistochemical analysis of HHV-6 DNA positive samples did not reveal any specific HHV-6B protein positive tumor cell. In contrast, supposed immune cells presented intra- and peritumorally expressed HHV-6B-protein. The cause of presence of these cells in the tumor stroma is unknown, as of yet. CONCLUSIONS: HHV-6 DNA-positivity of pancreatic cancer tissue described by us and others is probably not due to the infection of pancreatic cells by HHV-6, but rather due to the migration of HHV-6 positive immune cells into the pancreas. Based on our data, we suppose that there is no direct evidence for HHV-6 as a causative agent of pancreatic cancer, but further in-depth studies (including investigation of immune status of patients) are necessary to make definitive conclusions.

Detection of human herpesvirus 6 in pediatric CSF samples: causing disease or incidental distraction?

Interpretation of human herpesvirus type 6 (HHV6) detection in the cerebrospinal fluid (CSF) of children can be complex; the virus can cause acute infection, reactivation, or can be inherited chromosomally integrated (iciHHV6). Our objectives were to determine the prevalence of HHV6 including iciHHV6 in CSF and compare the clinical and laboratory characteristics with and without iciHHV6 in our patient population. Overall, the prevalence of HHV6 and iciHHV6 was 2.4% and 0.85%, respectively. Children with iciHHV6 were significantly younger and less likely to present with fever. Septic infants (≤60 days) accounted for 65.2% (15/23) of the iciHHV6 patients. Patients with iciHHV6 had higher viral loads in CSF and whole blood. Twenty-one (91.3%) patients with iciHHV6 and 12 (33.3%) without ici-HHV6 were determined to have an incidental detection of HHV6 not associated with presenting symptoms. Molecular detection of HHV6 in CSF is not always associated with HHV6 infection and may represent iciHHV6 particularly in infants evaluated for sepsis.

Inherited IRAK-4 Deficiency in Acute Human Herpesvirus-6 Encephalitis.

Human herpesvirus-6 (HHV-6) infection can rarely cause life-threatening conditions, such as encephalitis, in otherwise healthy children, with unclear pathogenesis. We studied a child who presented with acute HHV-6 encephalitis at the age of 10 months and who was homozygous for a novel missense mutation in IRAK4, encoding interleukin-1 receptor-associated kinase 4, identified by whole-exome sequencing. We tested the damaging impact of this mutation in silico by molecular dynamics simulations and in vitro by biochemical and functional experiments utilizing cell lines and patient's cells. We found that the mutation is severely hypomorphic, impairing both the expression and function of IRAK-4. Patient's leukocytes had barely detectable levels of IRAK-4 and diminished anti-viral immune responses to various stimuli inducing different Toll-like receptors and cytosolic nucleic acid sensors. Overall, these findings suggest that acute HHV-6 encephalitis can result from inborn errors of immunity to virus. This study represents the first report of isolated acute HHV-6 infection causing encephalitis in an inherited primary immunodeficiency, notably autosomal recessive (AR) partial IRAK-4 deficiency, and the first report of AR IRAK-4 deficiency presenting with a severe viral disease, notably HHV-6 encephalitis upon an acute infection, thereby expanding the clinical spectrum of IRAK-4 deficiency.

Anterior Uveitis Associated with Human Herpesvirus 7 Infection Diagnosed by Multiplex Polymerase Chain Reaction Assay: A Case Report.

BACKGROUND: Herpetic anterior uveitis (AU) is usually caused by the herpes simplex virus, varicella-zoster virus, and cytomegalovirus. Herein, we report a case of herpetic AU associated with human herpesvirus 7 (HHV-7) infection. STUDY DESIGN: A case report. CASE PRESENTATION: A 49-year-old female patient presented with complaints of blurred vision and hyperemia in the right eye. Slit-lamp examination revealed bilateral fine and a few small white keratic precipitates (KPs), Descemet membrane folds in the right eye, and severe and mild cellular infiltration in the anterior chamber of the right and left eye, respectively. HHV-7 viral DNA was detected by a polymerase chain reaction assay of an aqueous humor sample. The AU improved significantly with topical steroids. CONCLUSION: We report a rare case of herpetic AU characterized by fine and small white KPs in which only HHV-7 DNA was detected in the aqueous humor.

Human herpesvirus 7 encephalitis in an immunocompetent adult and a literature review.

BACKGROUND: Human herpesvirus 7 (HHV-7) is a common virus that infects children early and is accompanied by lifelong latency in cells, which is easy to reactivate in immunodeficient adults, but the underlying pathological mechanism is uncertain in immunocompetent adults without peculiar past medical history. Even though the clinical manifestation of the encephalitis caused by HHV-7 is uncommon in immunocompetent adults, the HHV-7 infection should not be neglected for encephalitis for unknown reasons. CASE PRESENTATION: We reported here a case of HHV-7 encephalitis with epileptic seizures. While the brain computer tomography was standard, electroencephalography displayed slow waves in the temporal and bilateral frontal areas, then HHV-7 DNA was detected in the metagenomic next-generation sequencing of cerebrospinal fluid. Fortunately, the patient recovered after treatment and was discharged 2 months later. We also collected the related cases and explored a better way to illuminate the underlying mechanism. CONCLUSION: The case indicates clinicians should memorize HHV-7 as an unusual etiology of encephalitis to make an early diagnosis and therapy.

Case Report: Overlapping Syndrome of Anti-NMDAR Encephalitis and MOG Inflammatory Demyelinating Disease in a Patient With Human Herpesviruses 7 Infection.

Objectives: This study reported a case of overlapping anti-N-methyl-D-aspartate receptor (NMDAR) encephalitis and myelin oligodendrocyte glycoprotein (MOG) inflammatory demyelinating disease with human herpesviruses 7 (HHV-7) infection. Methods: The detailed clinical characteristics, neuroimaging features, and outcomes of the patient were collected. Polymerase chain reaction (PCR), cell-based assay (CBA) and the tissue-based indirect immunofluorescence assay (TBA) were used for diagnosis. Results: The clinical manifestations included headache, dizziness, fever, optic neuritis, and epileptic-seizures. Brain magnetic resonance imaging (MRI) showed hyperintensities involving the left frontal, orbital gyrus and bilateral optic nerve with substantial contrast enhancement. Moreover, test for HHV-7 DNA by using the next generation sequencing metagenomics and polymerase chain reaction showed positive result in CSF but not in the serum samples. Anti-HHV-7 IgM and IgG antibodies were detected in both the serum and cerebrospinal fluid. NMDAR antibodies (1:10) were found positive in the patient's CSF by a cell-based assay, and MOG antibodies were positive in the serum (1:10) and CSF (1:32). The patient appeared to respond well to immune therapy and it was found that the clinical symptoms including epileptic-seizure as well as headache were relieved and cerebral lesions almost disappeared after the treatment. However, his vision was not completely restored even at the 8-month follow-up, especially the vision in his right eye which was more seriously damaged. Discussion: We report a rare case of MOG antibodies and anti-NMDAR encephalitis overlapping syndrome (MNOS) with HHV-7 infection for the first time. The possibility of MNOS needs be considered when optic neuritis occurs in the patients diagnosed with anti-NMDAR encephalitis. Besides, immunotherapy should be initiated as early as possible to improve the treatment outcomes and facilitate complete cure.