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Increasing incidence of nosocomial Chryseobacterium indologenes infections in Taiwan.

To understand the clinical features, antimicrobial therapy, and epidemiology ofChryseobacterium indologenes infections, the medical records of 36 patients with nosocomialChryseobacterium indologenes infections seen over a three-year period at National Taiwan University Hospital were reviewed. The 36 isolates recovered from these patients were studied by molecular typing and determination of antimicrobial susceptibility patterns. Nine patients had underlying neoplastic diseases, seven had diabetes mellitus, five had burn wounds, and four had uremia. The clinical syndrome included ten patients with intraabdominal infections, nine with wound sepsis, six with intravascular catheter-related bacteremia, and four with ventilator-associated pneumonia. Thirteen patients had monomicrobial bacteremia, and four had polymicrobial bacteremia. Nineteen patients (53%) developed infections associated with various indwelling devices. The deaths of five patients (14%) were directly attributable to infection withChryseobacterium indologenes. All isolates recovered showed a wide range of resistance to commonly used antimicrobial agents. The random amplified polymorphic DNA (RAPD) patterns of the isolates differed from each other, indicating the absence of epidemiological relatedness among these isolates. Nosocomial infection caused by multiresistantChryseobacterium indologenes appears to be an emerging problem in Taiwan and should be studied further.

Virological, Serological, and Antiviral Studies in an Imported Human Case of Avian Influenza A(H7N9) Virus in Taiwan

We describe the clinical course and virological characteristics of the first H7N9 influenza case in a Taiwanese patient; this patient had detectable viruses in the airway for 2 weeks, during which time an oseltamivir resistance-associated R292K mutation rapidly emerged. Anti-H7N9 antibody was detected 21 days after onset of symptoms, when H7N9 viral load declined significantly.

Re-emergence of meningococcal disease in Taiwan: circulation of domestic clones of Neisseria meningitidis in the 2001 outbreak

The annual incidence of meningococcal disease (meningitis and septicaemia) in Taiwan was 0.94/10(5) population in 1953. It then declined to below 0.001 from 1980 to 1987, and re-emerged in 2000 with a rate of 0.07/10(5) population. In 2001 there was a further increase in incidence (43 cases, 0.19/10(5)). Of 43 isolates of Neisseria meningitidis available for this study, including 41 from patients treated in 2001, three (7.0%) were penicillin insensitive (MIC > or = 0.12 microg/ml), though all were beta-lactamase negative: 16 (37.2%) were resistant to trimethoprim-sulphamethoxazole (MIC > or = 4/76 microg/ml). Serogrouping and genotype analysis revealed nine domestic clones. None of the 43 patients had any relationship (travel or contact history) with the 2000 or 2001 Hajj pilgrimage. Epidemiological information and typing results suggested wide dissemination of a limited number of domestic clones of N. meningitidis, manifesting as serogroups W-135, B and Y. Two clones of serogroup W-135 involved in the outbreak were genetically distinct from the 2000 or 2001 Hajj-related W-135 clone.

Typhoid fever and typhoid hepatitis in Taiwan.

The annual incidence of typhoid fever in Taiwan was 2.1-3.6 cases per 1,000,000 population from 1995 to 2002. More than 80% of 45 patients with typhoid fever treated at National Taiwan University Hospital from 1996 to 2002 had elevated serum aminotransferase levels at presentation. Ten of these patients were treated during an outbreak in Taipei County in 2002, and seven of them who did not have pre-existing liver disease developed hepatitis, which was unrelated to other aetiologies. All Salmonella typhi isolates were susceptible to extended-spectrum cephalosporins and fluoroquinolones. Multidrug resistance (intermediate resistance to ampicillin, trimethoprim-sulphamethoxazole, and chloramphenicol) was found in one (2.5%) of the 40 isolates studied. Pulsed-field gel electrophoresis analysis demonstrated a high genetic diversity among S. typhi isolates and identified a novel clone associated with the 2002 outbreak. Physicians should be alert to the possibility of typhoid fever when patients, without other gastrointestinal symptoms, present with sustained fever and hepatitis.

Evaluation of performance of human immunodeficiency virus antigen/antibody combination assays in Taiwan.

BACKGROUNDnThe fourth-generation human immunodeficiency virus (HIV) combination assay, which can simultaneously detect the presence of anti-HIV antibody and HIV antigen, has been shown to shorten the window period in HIV diagnosis compared with the third-generation HIV antibody immunoassay. This study was aimed to determine the performance of HIV combination assays in Taiwan, where the HIV-1 seroprevalence is 0.007% and HIV-2 infection has never been reported.nnnMETHODSnPerformance of three fourth-generation HIV Ag/Ab combination assays (Dia.Pro, Wantai, and Bio-Rad) and one third-generation HIV Ab immunoassay (AxSYM HIV 1/2 gO) was assessed.nnnRESULTSnA total of 152 specimens, including 86 confirmed HIV-seropositive and 66 HIV-seronegative samples, were used in the study. The sensitivity of four assays varied from 98.8% to 100%, and specificity varied from 98.5% to 100%. Performance of the 75 equivocal samples, the HIV status of which was confirmed later, in terms of negative prediction varied from 81.8% to 87.5%. The Bio-Rad and Dia.Pro assays exhibited higher sensitivity for the detection of p24 antigen among the three fourth-generation HIV combination assays.nnnCONCLUSIONnThe three fourth-generation HIV Ag/Ab combination assays exhibited better sensitivity, specificity, and negative prediction than the third-generation HIV Ab immunoassay.

Pseudo-outbreak of rotavirus infection in a neonatal intensive care unit.

BACKGROUNDnA rotavirus outbreak in a neonatal intensive care unit (NICU) may have catastrophic consequences for young infants receiving critical care. From May 13, 2011 to July 11, 2011, a significant increase in stool samples testing positive for rotavirus antigens in the NICU of a university affiliated hospital was observed. Due to lack of clinical presentations suggestive of rotavirus infection in the patients and the rarity of rotavirus infection in the NICU in the past, a pseudo-outbreak was suspected.nnnMETHODSnInfection control measures were reinforced initially. To investigate the outbreak, a prospective laboratory-based active surveillance of all infants in the NICU was conducted right after the cluster was identified. Repeated testing using a modified enzyme immunoassay (EIA) kit, rotavirus RNA polyacrylamide gel electrophoresis (PAGE), reverse transcription polymerase chain reaction (RT-PCR), and retrospective chart review methods were used to confirm the pseudo-outbreak.nnnRESULTSnSeven infants in the NICU, with or without gastrointestinal symptoms, tested positive for the rotavirus antigen using the old version of an EIA kit, which indicated a possible outbreak. Active surveillance with repeated tests for recollected stool samples using a modified EIA kit showed negative results in all 24 infants in the NICU. Seven stored stool samples from four infants, which previously tested positive for the rotavirus antigen, tested negative for rotavirus using the modified EIA kit, PAGE, and RT-PCR. Chart reviews showed no clinical difference between index cases and controls. False positivity might arise from unsatisfactory specificity of the old EIA kit. After the introduction of the modified EIA kit, no rotavirus was detected in the NICU for at least 7 months.nnnCONCLUSIONnThis cluster of patients who tested positive for the rotavirus antigen in stools was confirmed to be a pseudo-outbreak. Interpretation of the old EIA for rotavirus in an NICU setting should be done with caution until the mechanism of the false-positive reaction is elucidated.

Molecular epidemiology and clinical features of adenovirus infection in Taiwanese children, 2014

BACKGROUND/PURPOSESnHuman adenovirus (HAdV) infection is prevalent and has an important clinical impact on children. We aim to investigate the molecular epidemiology of HAdV infection and discover the correlations between clinical features and HAdV species in an HAdV outbreak of 2014.nnnMETHODSnThis is a retrospective study, enrolling patients under 19 years of age with HAdV infection at the National Taiwan University Hospital in 2014. We gathered the demographic and clinical data, carried out molecular typing and constructed a phylogenetic tree. Statistical analyses were performed in terms of HAdV species and hospitalization.nnnRESULTSnA total of 531 patients with HAdV infection were identified. HAdV-B accounted for the largest proportion (nxa0=xa0387, 73%). On average, patients infected with HAdV-E were oldest, whereas those with HAdV-C infection were youngest (pxa0<xa00.001). Patients with HAdV-B (HAdV-3) infection were associated with a lower incidence of co-infection with other viruses (pxa0<xa00.001). Complications occurred in 203 (38%) patients. There were 149 (28%) patients requiring hospitalization. The risk factors for hospitalization included underlying neurological abnormalities, prematurity and the diagnosis of pneumonia. Five patients (1%) had severe HAdV infection requiring intensive care; all of them fully recovered. The phylogenetic study showed that the partial hexon genes of HAdV-1, HAdV-3, HAdV-4 and HAdV-5 remain stable over time.nnnCONCLUSIONnWe established the molecular epidemiology of HAdV infection and demonstrated the relationship between clinical features and HAdV species.