[Effects of radical radiotherapy combined with different regimens of chemotherapy on radiation intestinal injury in patients with non-metastatic anal squamous cell carcinoma].

Objective: To investigate the effects of radical radiotherapy combined with different chemotherapy regimens (fluorouracil-based versus docetaxel plus cisplatin) on the incidence of radiation intestinal injury and the prognosis in patients with non-metastatic anal squamous cell carcinoma. Methods: A retrospective cohort study was conducted to recruit non-metastatic anal squamous cell carcinoma patients who underwent chemoradiotherapy in the Sixth Affiliated Hospital of Sun Yat-sen University and Nanfang Hospital from July 2013 to January 2021. Inclusion criteria: (1) newly diagnosed anal and perianal squamous cell carcinoma; (2) completed radical radiotherapy combined with concurrent chemotherapy; (3) tumor could be evaluated before radiotherapy. Exclusion criteria: (1) no imaging evaluation before treatment, or the tumor stage could not be determined; (2) patients undergoing local or radical resection before radiotherapy; (3) distant metastasis occurred before or during treatment; (4) recurrent anal squamous cell carcinoma. A total of 55 patients (48 from the Sixth Affiliated Hospital of Sun Yat-sen University and 7 from Nanfang Hospital) were given fluorouracil (the 5-FU group, n=34) or docetaxel combined with the cisplatin (the TP group, n=21). The evaluation of radiation intestinal injury, hematological toxicity and 3-year disease-free survival (DFS) rate were compared between the two groups. The effects of chemotherapy regimen and other clinicopathological factors on the incidence and severity of acute and chronic radiation intestinal injury were analyzed. The assessment of radiation intestinal injury was based on the American Cancer Radiotherapy Cooperation Group (RTOG) criteria. Results: During radiotherapy and within 3 months after radiotherapy, a total of 45 patients developed acute radiation intestinal injury, including 18 cases of grade 1 (32.7%), 22 cases of grade 2 (40.0%) and 5 cases of grade 3 (9.1%). No patient developed chronic radiation intestinal injury. Among the 34 patients in the 5-FU group, 21 had grade 2-3 radiation intestinal injury (21/34, 61.8%), which was significantly higher than that in the TP group (6/21, 28.6%) (χ(2)=5.723, P=0.017). Multivariate analysis showed that 5-FU chemotherapy regimen was an independent risk factor for radiation intestinal injury (HR=4.038, 95% CI: 1.250-13.045, P=0.020). With a median follow-up period of 26 (5-94) months, the 3-year DFS rate of patients in TP group and 5-FU group was 66.8% and 77.9%, respectively, whose difference was not significant (P=0.478). Univariate analysis showed that the DFS rate was associated with sex, age, tumor location, T stage, N stage, and induction chemotherapy (all P<0.05), while the DFS rate was not associated with chemotherapy regimen or radiation intestinal injury (both P>0.05). Multivariate analysis revealed that age ≥ 50 years old was an independent risk factor affecting the prognosis of patients (HR=8.301, 95% CI: 1.130-60.996, P=0.038). Conclusions: For patients with non-metastatic anal squamous cell carcinoma, radical radiotherapy combined with TP chemotherapy regimen can significantly reduce the incidence of radiation intestinal injury as compared to 5-FU regimen. However, due to the short follow-up time, the effect of different chemotherapy regimens on the prognosis is not yet clear.

Relationship between enteric pathogens and acute gastroenteritis disease severity: a prospective cohort study.

OBJECTIVES: To evaluate the relationship between individual bacterial and viral pathogens and disease severity. METHODS: Children <18 years with three or more episodes of vomiting and/or diarrhoea were enrolled in two Canadian paediatric emergency departments between December 2014 and August 2016. Specimens were analysed employing molecular panels, and outcome data were collected 14 days after enrolment. The primary outcome was severe disease over the entire illness (symptom onset until 14-day follow-up), quantified employing the Modified Vesikari Scale (MVS) score. The score was additionally analysed in two other time periods: index (symptom onset until enrolment) and follow-up (enrolment until 14-day follow-up). RESULTS: Median participant age was 20.7 (IQR: 11.3, 44.2) months; 47.4% (518/1093) and 73.4% (802/1093) of participants had index and total MVS scores ≥11, respectively. The most commonly identified pathogens were rotavirus (289/1093; 26.4%) and norovirus (258/1093; 23.6%). In multivariable analysis, severe disease over the entire illness was associated with rotavirus (OR = 9.60; 95%CI: 5.69, 16.19), Salmonella (OR = 6.61; 95%CI: 1.50, 29.17), adenovirus (OR = 2.53; 95%CI: 1.62, 3.97), and norovirus (OR = 1.43; 95%CI: 1.01, 2.01). Pathogens associated with severe disease at the index visit were: rotavirus only (OR = 6.13; 95%CI: 4.29, 8.75), Salmonella (OR = 4.59; 95%CI: 1.71, 12.29), adenovirus only (OR = 2.06; 95%CI: 1.41, 3.00), rotavirus plus adenovirus (OR = 3.15; 95%CI: 1.35, 7.37), and norovirus (OR = 0.68; 95%CI: 0.49, 0.94). During the follow-up period, rotavirus (OR = 2.21; 95%CI: 1.50, 3.25) and adenovirus (OR = 2.10; 95%CI: 1.39, 3.18) were associated with severe disease. CONCLUSIONS: In children presenting for emergency department care with acute gastroenteritis, pathogens identified were predominantly viruses, and several of which were associated with severe disease. Salmonella was the sole bacterium independently associated with severe disease.

[Comparison of epidermal growth factor receptor gene mutation in lung adenocarcinoma using biopsied tissue, pleural effusion and blood samples].

Objective: To compare different specimen types of lung adenocarcinoma in the detection of epidermal growth factor receptor (EGFR) gene and to correlate EGFR mutations with patient clinical features. Methods: One hundred lung adenocarcinoma cases were collected from June to December in 2015, at the First Affiliated Hospital of Xinjiang Medical University.Of the 100 lung adenocarcinoma samples, 43 were male and 57 were female. The age was from 40 to 88 years old, and the average age was 66 years. One hundred lung adenocarcinoma cases were divided equally into two groups. Mutation analysis of EGFR gene by real-time PCR was performed using biopsied tissue and paired blood samples in one group (n=50) and using pleural effusion and paired blood samples in the other group (n=50). Results: The mutation rate of EGFR gene in biopsy samples was 54% (27/50) , higher than that of blood samples (46%, 23/50), but without statistical differences (χ(2)=0.640, P=0.424). In contrast, mutation rate of EGFR gene in pleural effusion samples (42%, 21/50) was higher than that of blood samples (34%, 17/50), but without statistical differences(χ(2)=0.679, P=0.409). Two patients had EGFR mutation detected in paired blood samples but not in the corresponding biopsy samples, and four patients had EGFR mutation detected in pleural effusion samples but not in their paired blood samples. The mean progression-free survival of patients with detectable EGFR mutation were 9.5 months (tissue samples), 8.6 months (pleural effusion) and 8.5 months (blood). However, there was no statistical difference. Conclusions: Blood samples may be used to assess EGFR mutations for patients with lung adenocarcinoma. However, further studies are needed to improve the sensitivity and accuracy in the detection of EGFR mutations using blood samples.

[Impact of PRDM1 gene inactivation on C-MYC regulation in diffuse large B-cell lymphoma].

Objective: To investigate the role of PRDM1 gene inactivaion in the regulation of C-MYC in diffuse large B-cell lymphoma (DLBCL), and to explore the correlation of its immunophenotype and prognosis. Methods: 100 cases paraffin-embedded DLBCL tissues were collected from January 2009 to December 2015 at the First Affiliated Hospital of Xinjiang Medical University along with 20 cases of reactive proliferative lymph nodes as control. Immunohistochemical methods were used to detect the expression of CD20, CD10, MUM1, Ki-67, bcl-6, PRDM1/Blimp1, C-MYC and PAX5 protein. The tumors were classified into two subtypes according to Hans classification.The expression of PRDM1 and C-MYC gene in tumor group and control group was detected by reverse transcription PCR (RT-PCR) and the relationship between PRDM1 and C-MYC gene was analyzed.OCI-LY1 (GCB subtype) and OCI-LY3 (non-GCB subtype) cell lines were transfected with small interfering RNA by cationic liposome reagent transfection, and the expression of C-MYC in the transfected cell lines was detected by RT-PCR and Western blot. The Kaplan-Meier method was used to analyze the prognostic significance of PRDM1/Blimp1 and C-MYC at protein and mRNA levels. Results: There were 27 cases of GCB subtype and 73 cases of non-GCB subtype according to Hans classification. The positive expression of Blimp1 in DLBCL group and proliferative lymph nodes in control group was seen in 26(26.0%) and 20 cases(100%), respectively. There were 58 cases with high expression of PRDM1 at mRNA level, including 22 cases of GCB subtype and 36 cases non-GCB subtype, and the difference was statistically significant (P=0.004). There were differences in PRDM1 gene expression between the two immunological subtypes, serum lactate dehydrogenase (serum LDH) level, presence of B symptoms, tumor primary sites and other clinical pathological parameters, while C-MYC expression was different in gender, IPI score, and serum LDH levels. Upon PRDM1/Blimp1 gene silencing in the two cell lines, C-MYC protein and gene expression were up-regulated in the transfection group, compared with the blank control group and negative control group by reverse transcription PCR and Western blot analyses. Moreover, PRDM1 expression was significantly associated with C-MYC(χ(2)=7.648, P=0.006) at mRNA level. Conclusion: The up-regulation of C-MYC gene expression induced by PRDM1 inactivation in DLBCL may play an important role for the development of DLBCL.PRDM1 protein and mRNA are associated with immunophenotyping and PRDM1 mRNA is a marker of poor prognosis.

[Clinicopathologic characteristics of epidermal growth factor receptor mutations in non-small cell lung cancer in Xinjiang region].

Objective: To investigate the point mutation of epidermal growth factor receptor (EGFR) gene and clinicopathologic characteristics in patients with non-small cell lung cancers(NSCLC)of Xinjiang region. Methods: Five-hundred and eighty-two cases of paraffin-embedded tissue in patients with NSCLC were collected between January 2013 and December 2015 in the First Affiliated Hospital of Xinjiang Medical University. The DNA was extracted from these tissues by Qiagen kit, to test thirty-two mutations in EGFR exons 18, 19, 20 and 21 using fluorescent quantitative qRT-PCR technology by TaqMan probe; the clinicopathologic features of patients were analyzed according to the mutation status of EGFR. Results: There were 173 cases with EGFR gene mutation in 582 cases of paraffin-embedded tissue in patients with NSCLC, and the mutation rate was 29.7%(173/582). There were statistical difference in female patients (50.5%, 98/194), no history of smoking(47.3%, 96/203), high differentiation(6/9), adenosquamous carcinoma(6/11), peripheral location (34.9%, 88/252), and surgical specimens(38.2%, 83/217), respectively (P<0.05). Multiple factors Logistic analysis showed that gender, degree of differentiation, and pathologic types had statistical differences to EGFR when α=0.05. There were no statistical differences between other variants. Conclusions: There are higher rate EGFR gene mutation in women patients, non-smokers, and well-differentiated, adenocarcinoma. Gender, degree of differentiation and pathological patterns are independent influencing factors on EGFR mutation status.

Hepatitis A virus infection associated with cannabis use.

We identified a case of acute Hepatitis A virus (HAV) infection linked to cannabis use. The local Public Health department received report of a man in his mid-20s with a classic presentation of hepatitis - jaundice, abdominal pain, vomiting, general malaise, and dark urine - as well as elevated serum aminotransferase levels and a positive anti-HAV IgM. Upon questioning, he reported no contact with ill individuals, or travel outside his metropolitan area. His exclusive source of water was the local municipal supply. He reported consuming mainly pre-packaged lower risk foods from large chain-style supermarket stores and eating at several local restaurants. While administering the questionnaire, the investigator identified that the patient smoked cannabis. Upon request, the patient agreed to provide a sample of cannabis for testing purposes. A viral elution of fresh cannabis leaves was completed. The sequences derived from the patient's serum sample and the eluate from the cannabis leaves were identical, but did not match any other HAV sub-genotype 1B sequences from Canadian isolates within the National Microbiology Laboratory database. Hepatitis A virus can survive >60 days when dried and kept at room temperature and low humidity; HAV can remain infectious in water at room temperature for 300 days. It cannot be concluded with certainty that the cannabis was the source of the hepatitis A; however, as other sources were excluded, or were of lesser probability, the association of cannabis with his disease acquisition remains strong.

Assessment of human virus removal during municipal wastewater treatment in Edmonton, Canada.

AIMS: To assess the removal of viruses through the multiple steps of wastewater treatment in a full-scale municipal wastewater treatment plant in Alberta, Canada. METHODS AND RESULTS: Samples were collected after each of the five treatment steps for a period of 16 months. The amount of viruses and their infectivity were analysed using real-time quantitative PCR (qPCR) and integrated viral cell culture (ICC), respectively. Bacterial indicator Escherichia coli was also tested using membrane filtration. Seven viruses including Norovirus (NoV), Rotavirus (RV), Sapovirus (SaV), Astrovirus (AsV), Adenovirus (AdV), Enterovirus (EV) and JC virus (JCV) were detected in 16 primary effluents in which infectious viruses were present. Different treatment steps showed various efficiencies in virus removal, with membrane ultrafiltration as the most effective at 4·6-7·0 log reduction. CONCLUSIONS: We observed high prevalence of viruses in raw wastewater and different viral reduction after various treatment steps. The discharge of treated wastewater with infectious viruses represents potential risks to human, animal and environmental health. SIGNIFICANCE AND IMPACT OF THE STUDY: This study provides a comprehensive assessment of the removal of NoV, RV, SaV, AsV, AdV, EV, JCV and Reovirus from wastewater by current procedures of municipal wastewater treatment and discusses the applicability of various viruses as viral indicators for water quality.

Hcmv-miR-UL22A-5p: A Biomarker in Transplantation With Broad Impact on Host Gene Expression and Potential Immunological Implications.

Cytomegalovirus (CMV) encodes multiple microRNAs. While these have been partially characterized in vitro, their relevance to clinical CMV infection has not been evaluated. We analyzed samples from a cohort of solid organ transplant patients with CMV disease (n = 245) for viral microRNA expression. Several CMV microRNAs were readily detectable in patients with CMV disease in variable relative abundance. Expression level generally correlated with DNA viral load and the absence of viral microRNA was associated with faster viral clearance. Detection of hcmv-miR-UL22A-5p at baseline independently predicted the recurrence of CMV viremia upon discontinuation of antiviral therapy (OR 3.024, 95% CI: 1.35-6.8; p = 0.007). A combination of direct mRNA targeting by the microRNA and indirect modulation of gene expression involving isoforms of the transcriptional regulator C-MYC may be responsible for the broad effects seen in the association of gene transcripts with the RNA-induced silencing complex and in global protein expression upon hcmv-miR-UL22A-5p transfection. This novel study of in vivo viral microRNA expression profiles provides unique insight into the complexity of clinical CMV infection following transplantation. We provide evidence that viral microRNAs may have complex effects on gene expression and be associated with specific virologic and clinical outcomes, and thus could be further evaluated as biomarkers.

HDAC5 promotes cell proliferation in human hepatocellular carcinoma by up-regulating Six1 expression.

OBJECTIVES: Histone deacetylases (HDACs) plays important roles in the regulation of genes expression and contribute to the growth of cancer cells. The present study aimed to investigate the function of HDAC5 in human hepatocellular carcinoma (HCC). PATIENTS AND METHODS: The expression of HDAC5 in human hepatocellular carcinoma tissues and cells was detected. MTT assay was used to measure the proliferation of HCC cell lines. siRNA technology was employed to down-regulate the protein expression of HDAC5 and Six1. RESULTS: Western blot showed that the HDAC5 expression was increased in human HCC tissues. The mRNA and protein levels of HDAC5 were up-regulated in human HCC cell lines. MTT assay showed that over-expression of HDAC5 promoted cell proliferation in human HCC cell lines. Down-regulation of HDAC5 caused a significantly inhibition of liver cancer cells proliferation. Furthermore, we found that HDAC5 promoted the Six1 expression both at the mRNA and protein levels in HCC cell lines. CONCLUSIONS: The current study demonstrated for the first time that HDAC5 promoted HCC cell proliferation through up-regulation of Six1 expression and might provide novel therapeutic targets in the treatment of HCC.

Multicenter evaluation of a commercial cytomegalovirus quantitative standard: effects of commutability on interlaboratory concordance.

Commutability of quantitative reference materials has proven important for reliable and accurate results in clinical chemistry. As international reference standards and commercially produced calibration material have become available to address the variability of viral load assays, the degree to which such materials are commutable and the effect of commutability on assay concordance have been questioned. To investigate this, 60 archived clinical plasma samples, which previously tested positive for cytomegalovirus (CMV), were retested by five different laboratories, each using a different quantitative CMV PCR assay. Results from each laboratory were calibrated both with lab-specific quantitative CMV standards ("lab standards") and with common, commercially available standards ("CMV panel"). Pairwise analyses among laboratories were performed using mean results from each clinical sample, calibrated first with lab standards and then with the CMV panel. Commutability of the CMV panel was determined based on difference plots for each laboratory pair showing plotted values of standards that were within the 95% prediction intervals for the clinical specimens. Commutability was demonstrated for 6 of 10 laboratory pairs using the CMV panel. In half of these pairs, use of the CMV panel improved quantitative agreement compared to use of lab standards. Two of four laboratory pairs for which the CMV panel was noncommutable showed reduced quantitative agreement when that panel was used as a common calibrator. Commutability of calibration material varies across different quantitative PCR methods. Use of a common, commutable quantitative standard can improve agreement across different assays; use of a noncommutable calibrator can reduce agreement among laboratories.

Analysis and clinical correlation of genetic variation in cytomegalovirus.

BACKGROUND: Cytomegalovirus (CMV) displays genetic polymorphisms in multiple genes, which may result in important virulence differences. Glycoprotein N (gN) and immediate early 1 (IE1) are key viral genes and immune targets. We aimed to characterize the molecular epidemiology of gN and IE1 genotypes in organ transplant patients with CMV disease in the context of clinical and virologic endpoints. METHODS: A total of 240 patients with CMV disease had genotyping analysis by nested polymerase chain reaction assays and sequencing using blood samples obtained at disease onset. Results were correlated with viral clearance kinetics and recurrence. RESULTS: Complex patterns of gN and IE1 genotypes were present with no clear genetic linkages. No single genotype of IE1 or gN was associated with poorer outcome. For example, different gN or IE1 genotypes had comparable baseline viral load, clearance half-lives, time to clearance, and rates of virologic recurrence. Mixed infection was present at IE1 in 15.8% and gN in 21.9%, but analysis of a single gene was insufficient to detect all mixed infections. Infections caused by multiple strains, as opposed to single strains, were associated with higher baseline viral loads (P = 0.011), delayed viral clearance (P = 0.033), and higher rates of virologic recurrence (P = 0.008). CONCLUSIONS: Genetic diversity in CMV is complex. Specific gN or IE subtypes do not seem to affect in vivo viral virulence patterns in single-strain infections. Mixed infections demonstrate associations with virologic outcomes that single-strain infections do not.

Interlaboratory comparison of cytomegalovirus viral load assays.

To assess interlaboratory variability in qualitative and quantitative cytomegalovirus (CMV) viral load (VL) testing, we distributed a panel of samples to 33 laboratories in the USA, Canada and Europe who performed testing using commercial reagents (n = 17) or laboratory-developed assays (n = 18). The panel included two negatives, seven samples constructed from purified CMV nucleocapsids in plasma (2.0-6.0 log(10) copies/mL) and three clinical plasma samples. Interlaboratory variation was observed in both actual (range, 2.0-4.0 log(10) copies/mL) and self-reported lower limits of detection (range, 1.0-4.0 log(10) copies/mL). Variation observed in reported results for individual samples ranged from 2.0 log(10) (minimum) to 4.3 log(10) (maximum)(.) Variation was greatest at low VLs. Assuming +/- 0.5 log(10) relative to the expected result represents an acceptable result, 57.6% of results fell within this range. Use of commercially available reagents and procedures was associated with less variability compared with laboratory-developed assays. Interlaboratory variability on replicate samples was significantly greater than intralaboratory variability (p < 0.0001). The significant interlaboratory variability in CMV VL observed may be impacting patient care and limiting interinstitutional comparisons. The creation of an international reference standard for CMV VL assay calibration would be an important step in quality improvement of this laboratory tool.

Interlaboratory comparison of epstein-barr virus viral load assays.

To assess interlaboratory variability in qualitative and quantitative Epstein-Barr virus (EBV) viral load (VL) testing, we distributed a panel of samples to 28 laboratories in the USA, Canada and Europe who performed testing using commercially available reagents (n = 12) or laboratory-developed assays (n = 18). The panel included two negatives, seven constructed samples using Namalwa and Molt-3 cell lines diluted in plasma (1.30-5.30 log(10) copies/mL) and three clinical plasma samples. Significant interlaboratory variation was observed for both actual (range 1.30-4.30 log(10) copies/mL) and self-reported (range, 1.70-3.30 log(10) copies/mL) lower limits of detection. The variation observed in reported results on individual samples ranged from 2.28 log(10) (minimum) to 4.14 log(10) (maximum). Variation was independent of dynamic range and use of commercial versus laboratory-developed assays. Overall, only 47.0% of all results fell within acceptable standards of variation: defined as the expected result +/- 0.50 log(10). Interlaboratory variability on replicate samples was significantly greater than intralaboratory variability (p < 0.0001). Kinetics of change in VL appears more relevant than absolute values and clinicians should understand the uncertainty associated with absolute VL values at their institutions. The creation of an international reference standard for EBV VL assay calibration would be an initial important step in quality improvement of this laboratory tool.

Effect of rotavirus vaccine on Sapporo virus gastroenteritis in Finnish infants.

BACKGROUND: Sapporo-like viruses (SLVs) occur worldwide, but there is limited information about the SLV-associated gastroenteritis outside Japan. METHODS: Stool specimens from 1,432 episodes of gastroenteritis that occurred in children between 2 months and 2 years of age during a rotavirus vaccine trial (776 episodes in placebo-vaccinated and 656 in rotavirus-vaccinated infants) were examined for SLVs using a reverse transcription-PCR assay. The reverse transcription-PCR took advantage of new primers specific for Sapporo virus genetic clusters I, II and III; SV/SV82 (SV/Sapporo virus 82); SV/Lond92 (SV/ London 92); and SV/PV (Parkville virus). RESULTS: SLVs were detected in association with 132 (9.2%) of all episodes; in 80 (5.6%) episodes SLV was the only gastroenteritis virus detected. The epidemic season of SLVs peaked from March to May concurrently with rotaviruses and astroviruses and overlapping withNorwalk-like viruses. Clinically SLV gastroenteritis was characterized by a mild diarrheal disease, being sharply different from the Norwalk-like virus-associated "winter vomiting disease." Rotavirus vaccination did not have any effect on the number of SLV episodes, but the intensity and duration of SLV-associated diarrhea were reduced in rotavirus-vaccinated children compared with placebo-vaccinated children (P = 0.0008). CONCLUSIONS: SLVs are common causative agents of acute gastroenteritis in young Finnish children. SLV disease is characterized by diarrhea, which is usually mild but can be severe. By an unknown mechanism rotavirus vaccine seems to reduce the severity of SLV-associated diarrhea.

Natural human immunoglobulin G subclass responses to Plasmodium falciparum serine repeat antigen in Uganda.

Serum samples from Ugandan residents of a malaria-hyperendemic region were tested by enzyme-linked immunosorbent assay for reactivity against recombinant constructs of the 47 (SE47')- and 50 (SE50A)-kDa fragments of Plasmodium falciparum serine repeat antigen (SERA). Immunoglobulin (Ig) G3 and IgG1 were the predominant subclass responses to SE47' and SE50A, respectively. The geometric mean optical density (OD) for IgG3 anti-SE47' was significantly lower in children < 15 years compared with adults > or = 15 years (P < 0.0001). By contrast, the geometric mean IgG1 anti-SE50A was slightly higher in children compared with adults (P < 0.01). The proportion of high responders (ODs > 0.5) to SE47' was significantly lower in children compared with adults (P < 0.001), whereas the proportion of high responders to SE50A was comparable in children and adults (P = 0.07). This first detailed study of SERA in a malaria-hyperendemic region suggests that natural human IgG3 anti-SE47' might be associated with immunity to malaria.

Human caliciviruses in acute gastroenteritis of young children in the community.

Episodes of acute gastroenteritis in prospectively followed children between 2 months and 2 years of age were examined for rotaviruses, enteric adenoviruses, astroviruses, and human caliciviruses, including both Norwalk-like viruses (NLVs) and Sapporo-like viruses (SLVs), using PCR and reverse transcription (RT)-PCR assays. A virus was identified in 60% (502/832) of all episodes and in 85% of the moderately severe or severe episodes. Human caliciviruses were as common as rotaviruses, both being detected in 29% of the cases. NLVs accounted for a 20% etiologic share of all cases; the clinical picture was a moderately severe disease with vomiting as a predominant symptom. SLVs were detected in 9% of the cases, the clinical picture being a mild diarrheal disease. Astroviruses were found in 10% and enteric adenoviruses in 6% of the cases. Diagnosis with PCR and RT-PCR methods increases the detection of all gastroenteritis viruses, particularly human caliciviruses. As a group, human caliciviruses are common causative agents of gastroenteritis in children <2 years of age in Finland, and, of these, NLVs cause more severe disease than SLVs.

Rotaviruses detected by reverse transcription polymerase chain reaction in acute gastroenteritis during a trial of rhesus-human reassortant rotavirus tetravalent vaccine: implications for vaccine efficacy analysis.

BACKGROUND: Rotaviruses are routinely diagnosed by detection of rotavirus antigen in stools using an enzyme immunoassay (EIA). A sensitive method, like reverse transcription polymerase chain reaction (RT-PCR), may reveal more rotaviruses, but the clinical significance of such findings is not well established. OBJECTIVES: To study whether RT-PCR can detect more episodes of rotavirus-associated gastroenteritis than EIA and to determine how rotavirus RT-PCR findings might change efficacy analysis of a rotavirus vaccine trial, in which the outcome measure was rotavirus gastroenteritis diagnosis with EIA. STUDY DESIGN: We applied RT-PCR for detection of rotaviruses in gastroenteritis episodes encountered in an efficacy trial of rhesus-human reassortant rotavirus tetravalent (RRV-TV) vaccine, in a total of 2398 infants. During a follow-up, covering two rotavirus epidemic seasons, 256 cases of rotavirus associated gastroenteritis were detected by EIA; 226 were in the primary efficacy analysis period that included children who had received three doses of vaccine or placebo. RESULTS: With RT-PCR, 84 (33%) more cases of rotavirus gastroenteritis were diagnosed than with EIA, 65 of these were in the primary efficacy analysis period. Clinically, cases of rotavirus gastroenteritis diagnosed by RT-PCR were much milder (median severity score 6 on a 20-point scale) than those diagnosed by EIA (median score 11), P < 0.0001. RT-PCR revealed proportionally more G2 and G4 rotaviruses than EIA. G1 rotaviruses detected by RT-PCR were almost equally divided between RRV-TV (25) vaccine and placebo (28) groups, whereas an apparent vaccine protective effect was seen in the distribution of G2 (one in the RRV-TV and eight in the placebo group) and G4 rotaviruses (six in the RRV-TV and 14 in the placebo group). CONCLUSION: RT-PCR is a useful tool in the diagnosis of rotavirus gastroenteritis, particularly for cases associated with other than the epidemiologically dominant G-type. Application of RT-PCR contributes to the overall appraisal of performance of rotavirus vaccine.

Human astrovirus-associated gastroenteritis in children under 2 years of age followed prospectively during a rotavirus vaccine trial.

This study evaluated the clinical significance of human astrovirus-associated gastroenteritis in young children in the community. Placebo- (n = 1207) and rhesus rotavirus tetravalent (RRV-TV) vaccine- (n = 1191) recipient children were followed from 2 mo to 2 y of age. Stool specimens from 1528 episodes of acute gastroenteritis (805 in the placebo group and 723 in the RRV-TV vaccine group) were tested for astrovirus with a sensitive reverse transcription-polymerase chain reaction (RT-PCR) assay and positive results were confirmed by Southern hybridization using probes specific for astrovirus serotypes 1 and 2. Astroviruses were detected in 144 (9%) episodes of gastroenteritis; 92% of the findings were serotype 1 and 6% were serotype 2. The astrovirus peak season was in winter. Of the 102 children who had gastroenteritis with astrovirus as the only diarrhoea virus in the stools, 72% had watery diarrhoea, 59% had vomiting, 26% had fever, 5% needed oral rehydration and 3% were hospitalized. Overall, the clinical severity of astrovirus gastroenteritis was much lower than that of rotavirus gastroenteritis. RRV-TV rotavirus vaccine did not protect against astrovirus gastroenteritis. It is concluded that astroviruses are common causative agents in acute gastroenteritis in young children, but the symptoms of astrovirus gastroenteritis are usually mild and the illness is therefore only of minor clinical significance.