Sequence typing of human adenoviruses isolated from Polish patients subjected to allogeneic hematopoietic stem cell transplantation - a single center experience.

PURPOSE: Human adenoviruses (HAdV) from species A, B and C are commonly recognized as pathogens causing severe morbidity and mortality in hematopoietic stem cell transplant (HSCT) recipients. The purpose of the present study was to determine HAdV types responsible for viremia in HSCT recipients at a large tertiary hospital in Poland. METHODS: Analysis of partial nucleotide sequences of HAdV hexon gene was used to type 40 clinical isolates of HAdV obtained from 40 HSCT recipients. RESULTS: We identified six different HAdV serotypes belonging to species B, C and E. We demonstrated high variability in sequences of detected HAdV types, and patients infected with the same HAdV types were not hospitalized at the same time, which suggests the low possibility of cross-infection. In almost all patients, anti-HAdV antibodies in IgG class were detected, which indicates a history of HAdV infection in the past. Clinical symptoms accompanying HAdV viremia were in 89%, and in 61.5% of individuals, HAdV was a sole pathogen detected. There were no cases with high-level HAdV viremia and severe systemic or organ infections. Graft-versus-host disease (GvHD) was present in patients infected with species B and C, but grade II of GvHD was observed only in patients infected with HAdV-B. CONCLUSIONS: The predominance of HAdV-C and common presence of anti-HAdV antibodies in IgG class may strongly suggest that most infections in the present study were reactivations of HAdV persisting into the patient's mucosa-associated lymphoid tissues. Variability of HAdV sequences suggests that cross-infections between patients were very rare. ABBREVIATIONS: GvHD: graft-versus-host disease; HAdV: human adenoviruses; HSCT: hematopoietic stem cell transplantation.

[Prevalence of CI-HHV-6 in patients with hematological diseases and healthy donors in Poland - preliminary study].

of specific anti-HHV-6 antibodies in IgM and IgG classes and viral DNA. Quantitative real-time PCR assay was also used to determine viral load in alloHSCT recipients in plasma samples. Results: All individuals from studied group have not IgM antibodies against-HHV-6 prior transplantation. Specific IgG-class anti-HHV-6 antibodies were detected in 38 of 54 (70%) donors and in 47 of 54 recipients before HSCT (870/o), respectively. High load of HHV-6 DNA (>1x10A6 copies/ml) was detected in plasma samples taken only from one person (1,9%) of the 54 recipients. Conclusions: There is a high frequency specific anti-HHV-6 antibody in studied Polish patients; otherwise CI-HHV-6 was rare detected. Nonetheless, we urge careful observation of individuals with hematological malignances supposed to have CI-HHV-6. Further research on larger study group is needed to determine the clear role of CI-HHV-6 in alloHSCT recipients.

Incidence of adenoviral DNAemia in Polish adults undergoing allogeneic haematopoietic stem cell transplantation.

Human adenoviruses (HAdV) are important viral pathogens recognized increasingly in immunocompromised hosts, especially in allogeneic haematopoietic stem cell transplant recipients (alloHSCT). The clinical spectrum of HAdV disease ranges from asymptomatic viraemia and mild self-limiting disease to lower respiratory tract infection, multi-organ involvement and even death. Early detection and quantification of HAdV in peripheral blood using real-time PCR (qPCR) assay has been suggested as a useful monitoring tool, but is seldom used for regular surveillance of HAdV in haematology centers. A group of 112 alloHSCT recipients from two hospitals in Warsaw (Poland) was examined in the early post-transplant period using a quantitative qPCR assay. A total of 1,245 serum samples were evaluated for presence of HAdV DNA in patients where 66 (59 %) patients received grafts from unrelated donors whereas the other 46 (41 %) from sibling donors. HAdV sequences were detected in 64 (57 %) of the 112 patients. In 22 of all patients (20 %) HAdV DNA was detected only in a single positive sample, while 42 (37 %) had positive results in two or more subsequent sera. In total, DNAemia was present in 202 sera samples (16 %) with median time to observation of 47 days. Graft-versus-host disease (GvHD) was observed in 18 (28 %) adenovirus-infected transplant recipients and a significant correlation between HAdV infections and GvHD clinical presentation was found (p = 0.018). There is a high prevalence of HAdV infections in HSCT recipients in Poland during early post-transplant period. In consequence, we could only speculate if HAdV DNAemia could be also related to GvHD symptoms, enforcing the important pathogenic role of these viral infections in clinical complications post-alloHSCT.

[Adenovirus infection in immunocompromised patients]. / Zakazenia adenowirusami u pacjentów z zaburzeniami odpornosci.

Human adenoviruses belong to the Adenoviridae family and they are divided into seven species, including 56 types. Adenoviruses are common opportunistic pathogens that are rarely associated with clinical symptoms in immunocompetent patients. However, they are emerging pathogens causing morbidity and mortality in recipients of hematopoietic stem cell and solid organ transplants, HIV infected patients and patients with primary immune deficiencies. Clinical presentation ranges from asymptomatic viraemia to respiratory and gastrointestinal disease, haemorrhagic cystitis and severe disseminated illness. There is currently no formally approved therapy for the treatment of adenovirus infections. This article presents current knowledge about adenoviruses, their pathogenicity and information about available methods to diagnose and treat adenoviral infections.

[Application of FilmArray assay for detection of respiratory tract infections in immunocompromised persons]. / Wykorzystanie techniki FilmArray w diagnostyce zakazen dróg oddechowych u osób z niedoborami odpornosci.

INTRODUCTION: A variety of viruses and bacteria are responsible for acute upper and lower respiratory tract infections worldwide. Severe and even fatal disease can occur especially in group ofimmunocompromised individuals. Accurate pathogen identification allows clinicians to determine the need for ancillary diagnostic testing, antibacterial and/or antiviral therapy and can motivate decisions regarding hospitalization and infection control measures. METHODS: We compared the diagnostic performance of FilmArray Respiratory Panel highly multiplexed nucleic acid amplification test with previous used direct immunofluorescence assay. Both assays were performed on a panel of 6 nasopharyngeal-secretion specimens and 6 BALF samples, collected from 12 patients, subjected to allogeneic haematological stem cells transplantation, with lower respiratory tract symptoms. RESULTS AND CONCLUSIONS: Among viruses detectable by both assays were especially influenzaA virus, parainfluenza viruses type 3 and respiratory syncytial virus. In conclusion, the FilmArray assay is rapid and extremely user-friendly system, with results available in just over one hour with almost no labor involved. In few laboratories its low throughput and qualitative results may be a disadvantage in some clinical settings.

[Real-time PCR test for detection and quantification of human polyomavirus BK (BKV) DNA]. / Zastosowanie metody real-time PCR do wykrywania DNA ludzkiego poliomawirusa BK.

The human polyomavirus BK (BKV) is wide-spread pathogen, associated with urogenital tract disorders or even nephropathy in immunosuppressed patients. Nowadays molecular detection by real-time PCR (qPCR) is recognized as a method-of-choice for detecting human polyomaviruses in clinical samples. The aim of the study was development of real-time PCR assay for detection and quantification of polyomavirus BK DNA in clinical samples, using specific primers targeting a viral DNA VP3 gene and a TaqMan hydrolyzing probe. The analytical sensitivity of assay was tested using serial dilutions of BKV DNA in range between 13500 and 15 copies/ml. 27 urine samples and 23 plasma samples taken from a group of 22 adult recipients of allogeneic HSCT were tested for the presence of polyomavirus BK in the LightCycler system. Described in-house real-time PCR assay detected BKV DNA in 8 specimens (6 urine and 2 plasma). Detected average viral load was 170 copies/ml for plasma and 1250 copies/ml for urine samples, respectively. The results of this study show that developed TaqMan-based probe qPCR assay is very reliable and valuable for detection and quantification of BKV DNA, both in urine and plasma samples. These data, combined with its rapid turnaround time for results and decreased hands-on time, make the LightCycler PCR assay highly suitable for the rapid diagnostics of polyomavirus BK infections in the clinical laboratory.

Disseminated adenovirus disease in immunocompromised patient successfully treated with oral ribavirin: a case report.

In patients with immunological disorders, adenovirus infections are associated with significant rates of morbidity and mortality. Only few hematological units use molecular virological methods, such as polymerase chain reaction, for surveillance of adenovirus infection, and treatment strategies have never been evaluated in multicenter clinical trials. This report describes the detection and treatment of human adenovirus (HAdVs) disseminated disease in the case of a 46-year-old immunocompromised female having myelodysplastic syndrome with refractory cytopenia with multilineage dysplasia: International Prognostic Scoring System 1. Serum and urine samples were tested for the presence of adenoviral DNA using the quantitative real-time polymerase chain reaction (PCR) assay. For additional confirmation, sequencing of PCR products was also performed. With real-time PCR, we detected HAdV DNA in both serum and urine samples. The viral level constantly decreased with applied oral ribavirin therapy. As the result of sequencing, HAdVs type 11 was determined. Surveillance of adenovirus by real-time PCR is useful in detecting and monitoring disseminated HAdV infection; it is a potential standard diagnostic approach that could assist clinicians to decide whether antiviral therapy ought to be administered.

[Real-time PCR assay for detection and quantification of human adenoviruses in patients with haematological malignancies and symptoms of lower respiratory tract infection]. / Wykorzystanie ilosciowej reakcji Lanjcuchowej polimerazy w czasie rzeczywistym do wykrywania zakazen dolnych dróg oddechowych wywolanych adenowirusami u osób z chorobami nowotworowymi ukladu krwiotwórczego.

Human adenoviruses (HAdV) are one of the im-portant infectious etiological factors that affect immunocompromised patients. Because of the large number of HAdV serotypes and their genomic variations, they present a lot of difficulty in laboratory diagnostics. The recent introduction of real-time PCR (qPCR)-based assays has opened new ways to rapid, specific, and highly sensitive HAdV detection. For detection and quantification of HAdV DNA we retrospectively tested serum and bronchoalveolar lavage fluid (BALF) samples obtained from a cohort of 60 adult patients with haematological malignancies presenting clinical and radiological symptoms of lower respiratory tract infections. Human adenoviruses DNA was detected by qPCR method, using primers targeting a conserved region of the adenoviral hexon gene and a specific TaqMan probe. Adenovirus infection occurred with a high incidence in our study group patients. Using qPCR we found that a 21,7% and 15,0% of patients had adenoviral DNA in BALF and serum samples, respectively. The high level of sensitivity, specificity and accuracy provided by real-time PCR assay are favorable for the use in the detection of adenoviral DNA in clinical specimens, especially in immunocompromised patients.