35 research outputs found
Detection of adenovirus hepatitis and acute liver failure in allogeneic hematopoietic stem cell transplant patients
Human adenovirus (HAdV) is an important cause of the common cold and epidemic keratoconjunctivitis in immunocompetent individuals. In immunocompromised patients, HAdV can sometimes cause severe infection such as cystitis, gastroenteritis, pneumonia, encephalitis, hepatitis, or disseminated disease, resulting in significant morbidity and also mortality. In particular, severe cases have been reported in patients after allogeneic hematopoietic stem cell transplantation (allo‐HSCT). Indeed HAdV has been recognized as a pathogen that requires careful monitoring in allo‐HSCT patients. While HAdV hepatitis leading to severe acute liver failure is rare, such liver failure progresses rapidly and is often fatal. Unfortunately, HAdV hepatitis has few characteristic symptoms and physical findings, which makes it difficult to promptly confirm and start treatment. We report here four cases of HAdV hepatitis after allo‐HSCT and their autopsy findings
Infectious virus shedding duration reflects secretory IgA antibody response latency after SARS-CoV-2 infection
新型コロナウイルス排出と粘膜抗体の関係を解明 --呼吸器ウイルスのヒト間伝播を制御・予防する第一歩--. 京都大学プレスリリース. 2023-12-25.Articles: Infectious virus shedding duration reflects secretory IgA antibody response latency after SARS-CoV-2 infection. 京都大学プレスリリース. 2023-12-25.Infectious virus shedding from individuals infected with severe acute respiratory syndrome-coronavirus 2 (SARS-CoV-2) is used to estimate human-to-human transmission risk. Control of SARS-CoV-2 transmission requires identifying the immune correlates that protect infectious virus shedding. Mucosal immunity prevents infection by SARS-CoV-2, which replicates in the respiratory epithelium and spreads rapidly to other hosts. However, whether mucosal immunity prevents the shedding of the infectious virus in SARS-CoV-2-infected individuals is unknown. We examined the relationship between viral RNA shedding dynamics, duration of infectious virus shedding, and mucosal antibody responses during SARS-CoV-2 infection. Anti-spike secretory IgA antibodies (S-IgA) reduced viral RNA load and infectivity more than anti-spike IgG/IgA antibodies in infected nasopharyngeal samples. Compared with the IgG/IgA response, the anti-spike S-IgA post-infection responses affected the viral RNA shedding dynamics and predicted the duration of infectious virus shedding regardless of the immune history. These findings highlight the importance of anti-spike S-IgA responses in individuals infected with SARS-CoV-2 for preventing infectious virus shedding and SARS-CoV-2 transmission. Developing medical countermeasures to shorten S-IgA response time may help control human-to-human transmission of SARS-CoV-2 infection and prevent future respiratory virus pandemics
Enterovirus-Associated Hand-Foot and Mouth Disease and Neurological Complications in Japan and the Rest of the World
Enteroviruses (EVs) are responsible for extremely large-scale, periodic epidemics in pediatric cohorts, particularly in East and Southeast Asia. Clinical presentation includes a diverse disease spectrum, including hand-foot and mouth disease (HFMD), aseptic meningitis, encephalitis, acute flaccid paralysis, and acute flaccid myelitis. HFMD is predominantly attributable to EV-A types, including the major pathogen EV-A71, and coxsackieviruses, particularly CV-A6, CV-A16, and CV-A10. There have been multiple EV-A71 outbreaks associated with a profound burden of neurological disease and fatal outcomes in Asia since the early 1980s. Efficacious vaccines against EV-A71 have been developed in China but widespread pediatric vaccination programs have not been introduced in other countries. Encephalitis, as a consequence of complications arising from HFMD infection, leads to damage to the thalamus and medulla oblongata. Studies in Vietnam suggest that myoclonus is a significant indicator of central nervous system (CNS) complications in EV-A71-associated HFMD cases. Rapid response in HFMD cases in children is imperative to prevent the progression to a CNS infection; however, prophylactic and therapeutic agents have not been well established internationally, therefore surveillance and functional studies including development of antivirals and multivalent vaccines is critically important to reduce disease burden in pediatric populations
Molecular Epidemiology of Echoviruses 11 and 13, Based on an Environmental Surveillance Conducted in Toyama Prefecture, 2002-2003
Nineteen echovirus 11 (E11) and 12 E13 isolates were isolated from three rivers in Toyama Prefecture, Japan, during an environmental surveillance conducted from April 2002 to March 2003. The nucleotide sequences of E13 isolates were closely related to those from patients with aseptic meningitis, with less than 1.3% divergence in the VP1 region of the viral capsid gene, and belonged to the same clade responsible for a worldwide outbreak that started in 2000. In contrast, E11 isolates were clustered into three genomic groups and were not closely related to echovirus strains isolated from patients. These results suggest that the combination of both virus isolation from environmental sources and phylogenetic analysis could be complementary assessment approaches to trace prevalent and minor circulating enteroviruses in the human population
Evaluation of a Bedside Immunochromatographic Test for Detection of Adenovirus in Respiratory Samples, by Comparison to Virus Isolation, PCR, and Real-Time PCR
An immunochromatography (IC) kit for human adenovirus (HAdV) was evaluated with 138 patient nasopharyngeal samples. The samples were collected at a sentinel clinic in Japan from January through June 2003. Patients were diagnosed by clinical manifestation of pharyngoconjunctival fever (n = 38) or exudative tonsillitis (n = 100). The IC kit was positive for 84% (116 of 138) of patients diagnosed at bedside. The remaining extract solution of the IC kit test was transferred into maintenance medium and tested via laboratory diagnoses. The IC kit had 95% sensitivity (116 of 122 patients) with HAdV isolation (isolation) as the standard and 91% sensitivity (116 of 128 patients) with PCR as the standard. All of the IC kit-positive samples were isolation and PCR positive. Similarly, all the isolation-positive samples were PCR positive. Twenty-two IC kit-negative samples were evaluated by real-time PCR. Six samples were IC kit negative and isolation positive and contained 3.8 × 10(7) to 2.5 × 10(9) copies of the HAdV genome/ml. Five samples that were only PCR positive contained 3.0 × 10(4) to 3.8 × 10(5) copies of the HAdV genome/ml, but one sample was real-time PCR negative. We conclude that the IC kit is a useful bedside diagnostic tool for HAdV infections because it has 95% sensitivity (compared to isolation), but a negative result does not always rule out HAdV infection
Infectious human adenoviruses are shed in urine even after disappearance of urethral symptoms.
BACKGROUND:Urethritis is a common sexually transmitted disease, and human adenoviruses (HAdVs) have been found to be associated with nonchlamydial nongonococcal urethritis. However, the level and viability of HAdV in the urine of patients with urethritis remain unclear. METHODS:Male patients with urethritis and an asymptomatic group were screened using their First-void urine (FVU) for urethritis-related pathogens to identify those with HAdV DNA. FVU and gargle fluid were collected from all patients including from those in the asymptomatic group. A swab of eye discharge was also collected from patients with eye symptoms. The pharyngeal and/ or ocular fluid was also screened only in cases in which FVU was positive for HAdV DNA. HAdVs were isolated using A549 cell lines and typed by sequencing, and viral shedding during 2 years was quantified using real-time PCR. The prevalence of HAdV was assessed in the urethritis and asymptomatic groups, and viral load, isolated HAdV types, and urethral symptoms were compared between the groups. RESULTS:The positive detection rate of HAdV DNA was significantly higher in the urethritis group than in the asymptomatic group. Of 398 patients with urethritis, HAdV was isolated in all 32 cases (23 cases in which only HAdV DNA was detected with a mean of 2 × 109 copies/mL in urine samples). Of 124 control cases, one had HAdV monoinfection. The most frequently detected HAdV type was 56, followed by types 37 and 64. Regarding the relationship between symptoms and isolated HAdVs, the virus was isolated for up to 12 days after urethritis symptoms disappeared. CONCLUSIONS:HAdVs were significantly detected and isolated from the FVU of patients with urethritis. Furthermore, high levels of infectious HAdVs are excreted in urine for a long period even after urethritis symptoms disappear
Simultaneous development of Kawasaki disease following acute human adenovirus infection in monozygotic twins: A case report
Abstract Background The etiology of Kawasaki disease (KD) remains unknown. However, many studies have suggested that specific genetic factors and/or some infectious agents underlie the onset of KD. Previous studies have suggested that human adenovirus (HAdV) is one of the triggering pathogens of KD. Here, we report monozygotic twin boys who sequentially developed KD in conjunction with acute HAdV type 3 (HAdV-3) infection. Case presentation The patients were four-year-old monozygotic twin boys. The elder brother developed a high fever and was diagnosed with HAdV infection with an immunochromatographic kit for HAdV (IC-kit). He was transferred to our institute after persistent fever for 7 days. On admission, he already fulfilled all the diagnostic criteria for KD. His laboratory data were as follows: WBC, 9700/μl; CRP, 2.42 mg/dl; IFN-γ, 99.8 pg/ml; and TNF-α, 10.9 pg/ml. He received intravenous immunoglobulin (IVIG) and aspirin and responded well, with no coronary artery abnormalities. The younger brother, who was also IC-kit-positive, was hospitalized on the same day as his elder brother after persistent fever for 3 days. His data on admission were as follows: WBC, 12,600/μl; CRP, 5.54 mg/dl; IFN-γ, 105.0 pg/ml; and TNF-α, 33.6 pg/ml. Although he developed all of the typical KD symptoms by day 4, his fever subsided spontaneously on day 6 without IVIG or aspirin. However, he developed a dilation of the coronary artery in the region of the left circumflex artery bifurcation on day 10. His coronary artery dilation had resolved 3 months after onset. HAdV-3 DNA was detected with PCR in stool samples from both patients, and HAdV3 was isolated from the younger brother’s stool sample. Serum neutralizing antibodies to AdV3 were also significantly elevated in both patients, suggesting seroconversion. Conclusions There have been few reports of the simultaneous development of KD in monozygotic twins. Notably, both twins had an acute HAdV-3 infection immediately before they developed KD. These cases strongly suggest that KD was triggered by HAdV-3 infection, and they indicate that specific immune responses to some pathogens (such as HAdV-3), arising from genetic susceptibility, play a critical role in the pathogenesis of KD