[Underestimated infection - on the question of the human adenovirus pathogenicity factors.]

Human adenoviruses cause different organ infections of varying severity, from asymptomatic to severe cases with lethal outcome, that are registered everywhere. Detailed and focused study of factors predisposing to a severe course of infection is required. The literature contains information indicating the association of severe adenoviral respiratory diseases with certain types of adenovirus, primarily type 7. This review highlights the possible causes of increased pathogenicity of some types of adenovirus and their association with severe forms of infection. Pathogenicity factors include the ability of adenovirus to bind the specific cellular receptors, the formation of subviral particles, the interaction with blood proteins, in particular the coagulation factor X, as well as the features of the early genes E1A, E1B, E3, E4. In addition, the severity of the disease may be affected by the presence or absence of pre-existing antibodies specific to certain types of adenoviruses. Chronic diseases or immunosuppression also increase the risk of severe adenovirus infection. The information presented in this review may elucidate the pathogenesis of adenovirus infection, and help to develop new features for prevention and treatment.

[A case of adenovirus infection complicated by gram-negative polymicrobial sepsis: A clinical and morphological observation].

Among respiratory infections, adenovirus infection (ADVI), in the presence of which there may be severe pneumonia that frequently results in a fatal outcome, occupies particular attention. ADVI in patients without immunodeficiency is usually mild and shows a limited extent of injury. At the same time the disease in immunocompromised individuals may be severe, presenting with viremia, evolving sepsis, and high death rates. The paper gives a characteristic example of severe ADVI and its fatal outcome.

[ADENOVIRUSES IN THE ETIOLOGICAL STRUCTURE OF ACUTE RESPIRATORY VIRAL INFECTION IN MOSCOW IN 2004 - 2014].

AIM: Study prevalence of adenovirus species and serotypes that had caused acute respiratory viral infection (ARVI) in Moscow in 2004 - 2014. MATERIALS AND METHODS: Material from respiratory tract of 4731 patients with ARVI and 663 conditionally healthy children and adults was used. ARVI causative agents were detected by PCR with real-time detection using AmpliSens reagent kits (CRIE, Moscow). Membership of adenoviruses to a certain serotype was determined by sequencing of hexon gene segment. Adenoviruses that had caused ARD in servicemen in 2010 - 2014 were also studied. RESULTS: ARVI causative agents were detected in 64.6% ill children and 58% of adults. Respiratory-syncytial and rhinoviruses prevailed in children, influenza A virus--in adults. Adenoviruses were detected in 6.9% of ill children and 2.9% of adults during the whole year, with a rise in October-December. B and C species occurred at an equal frequency, E species was found less often. Serotypes 3 and 2 prevailed in 34% and 21% of cases of adenovirus mono-infection, respectively, serotypes 7, 6 and 4 occurred less often. 4 out of 5 outbreaks of adenovirus infection in servicemen were caused by serotype 7. Adenoviruses were absent in the group of healthy adults, in conditionally healthy children were detected in 0.4% of cases and were attributed to serotypes 1 and 2. CONCLUSION: Etiological structure of ARVI was studied for the last decade. Adenovirus infection ranked 5th in children and 7th in adults. 9 serotypes of 3 species of respiratory adenoviruses were identified. Varying prevalence of species and serotypes depending in season, clinical diagnosis and patient age was demonstrated.

[Adenovirus pneumonia with a fatal outcome in adults].

AIM: To retrospectively analyze the medical records of patients who have died from complications of community-acquired pneumonia (CAP) caused by adenovirus serotype 7. SUBJECTS AND METHODS: CAP was diagnosed in patients (6 men aged 19-24 years and 1 woman aged 49 years) on the basis of clinical, laboratory, and radiological findings. Adenoviral pneumonia was established by real-time polymerase chain reaction (PCR). Adenovirus DNA was detected in the patients' autopsy samples (lungs, brain, spleen, liver, blood). The adenoviruses were referred to as B1 serotype 7 on the basis of hexone gene sequencing results. Other potential causative agents of pneumonia were excluded by a battery of molecular genetic tests for a wide range of viral and bacterial pathogens of acute respiratory tract infections. RESULTS: In all cases, the disease began acutely with fever (37.8 to 39 °C), weakness, headache, a sore throat, a dry, unproductive cough or runny nose. Clinical deterioration during symptomatic therapy led to hospital admission for CAP on disease days 2-11. The patients continued to feel worse during massive antibiotic therapy, by switching a drug one to six times and by simultaneously using 2-4 antibiotics and intensive therapy. Death occurred on disease days 10-24. Postmortem examination of all the patients revealed acute respiratory distress syndrome and multiple organ failure. CONCLUSION: Adenovirus pneumonia causes diagnostic and therapeutic problems for clinicians. The clinical introduction of PCR methods for the diagnosis of viral infections allow the clinicians to elaborate and timely use effective management tactics in patients with adenoviral pneumonia and to prevent their death. It is necessary to design etiotropic therapy agents and to introduce the specific prevention of adenovirus infection in risk groups.