1.A retrospective analysis of antifungal susceptibilities of Candida bloodstream isolates from Singapore hospitals.
Thean Yen TAN ; Ai Ling TAN ; Nancy W S TEE ; Lily S Y NG
Annals of the Academy of Medicine, Singapore 2008;37(10):835-840
INTRODUCTIONWorldwide, Candida albicans is the most common Candida species implicated in bloodstream infections. However, the proportion of non-albicans bloodstream infections is increasing. Fluconazole resistance is known to be more common in non-albicans species, but is also reported in C. albicans. This retrospective study was performed to determine the species epidemiology of Candida bloodstream infections in Singapore hospitals, and to perform susceptibility testing to a range of antifungal drugs.
MATERIALS AND METHODSCandida spp. isolated from bloodstream infections from October 2004 to December 2006 were collected from 3 participating hospitals: a tertiary referral hospital (Singapore General Hospital), a secondary referral hospital (Changi General Hospital) and an obstetrics/paediatric hospital [KK Women's and Children's Hospital (KKWCH)]. Isolate collection was also retrospectively extended to January 2000 for KKWCH because of the limited number of cases from this hospital. Isolates were identified by a common protocol, and antifungal susceptibility testing was performed by microbroth dilution (Sensititre One, Trek Diagnostics, United Kingdom).
RESULTSThe most common isolates were C. albicans (37%), C. tropicalis (27%) and C. glabrata (16%). There were differences in species distribution between institutions, with C. parapsilosis and C. albicans predominant in KKWCH, and C. albicans and C. tropicalis predominant in the other 2 institutions. Fluconazole resistance was detected in 3.2% of all Candida spp., and 85.3% were classified as susceptible. All C. albicans and C. parapsilosis were susceptible to fluconazole and voriconazole, while susceptibility to fluconazole was much more variable for C. glabrata and C. krusei.
CONCLUSIONThis study shows that C. albicans remains the predominant Candida species isolated from bloodstream infections in the 3 participating hospitals. However, non-albicans species accounted for nearly two-thirds of all cases of candidaemia. Resistance to fluconazole was uncommon, and was generally confined to C. krusei and C. glabrata.
Antifungal Agents ; pharmacology ; Candida ; classification ; drug effects ; isolation & purification ; Candidiasis ; drug therapy ; epidemiology ; microbiology ; Cross Infection ; epidemiology ; microbiology ; Drug Resistance, Fungal ; drug effects ; Female ; Fungemia ; epidemiology ; microbiology ; Hospitals, University ; Humans ; Microbial Sensitivity Tests ; Retrospective Studies ; Singapore ; epidemiology
3.Risk Factors for Complicated Influenza A (H1N1) 2009 Disease in Children.
Chia Yin CHONG ; Natalie Wh TAN ; Anita MENON ; Koh Cheng THOON ; Nancy W S TEE ; Sheng FU
Annals of the Academy of Medicine, Singapore 2013;42(5):232-236
INTRODUCTIONSingapore had its first case of pandemic influenza A (H1N1) 2009 on 26 May 2009. As of 3 August 2009, 440 children with confirmed H1N1were admitted to KK Women's and Children's Hospital (KKH).
MATERIALS AND METHODSThis is a retrospective case control study of children admitted from 26 May 2009 to 19 July 2009 with H1N1infection. Cases and controls were first differentiated by whether they were complicated or non-complicated in nature, and subsequently analysed with regards to possible independent risk factors.
RESULTSWe analysed 143 admitted children; 48 cases and 95 controls (1: 2 ratio). Significant comorbidity was found in 20.3% (n = 29) of patients with the majority having asthma (n = 18, 12.6 %) followed by obesity (n = 7, 4.9%). Binary logistic regression analysis showed risk factors for complicated disease were comorbidity (adjusted OR 6.0, 95% CI, 2.5 to 14.6, P < 0.0001) and age <2 years (adjusted OR 9.8, 95% CI, 2.4 to 40, P = 0.001). Age less than 5 years was not found to be a risk factor.
CONCLUSIONIn the early stages of an evolving influenza epidemic when oseltamivir stocks are low, oseltamivir treatment for influenza can be streamlined and offered to those at highest risk who are under 2 years old or have significant comorbidity to prevent complicated disease.
Adolescent ; Age Factors ; Antiviral Agents ; therapeutic use ; Asthma ; complications ; Bronchitis ; complications ; Case-Control Studies ; Child ; Child, Preschool ; Cohort Studies ; Female ; Fluid Therapy ; Gastritis ; virology ; Gastroenteritis ; virology ; Humans ; Infant ; Influenza A Virus, H1N1 Subtype ; isolation & purification ; Influenza, Human ; complications ; Male ; Obesity ; complications ; Oseltamivir ; therapeutic use ; Pneumonia, Bacterial ; complications ; Retrospective Studies ; Risk Factors ; Seizures ; complications ; Singapore
4.Paediatric inflammatory bowel disease in a multiracial Asian country.
Hui Ping CHU ; Veena LOGARAJAH ; Nancy TAN ; Kong Boo PHUA
Singapore medical journal 2013;54(4):201-205
INTRODUCTIONThis study examined the characteristics and trends in the incidence of inflammatory bowel disease (IBD) among children in Singapore.
METHODSWe retrospectively reviewed all patients under 18 years diagnosed with IBD over a 14-year period. Information on demographics, disease presentation, laboratory findings, radiological investigations, and endoscopic and histological findings were obtained from the patients' medical records.
RESULTS32 patients were diagnosed with IBD, 30 of whom had Crohn's disease and 2 had ulcerative colitis. The incidence of IBD rose from an initial rate of 2.2 per 100,000 patients in the year 2000 to a peak of 11.4 patients per 100,000 patients by 2008. Median age of onset of symptoms was 10.5 years. There were more boys (63%) than girls in the group and a higher representation of Indians (34.4%). The most common presenting symptoms were abdominal pain (87.5%), diarrhoea (75.0%) and weight loss (71.9%). Extraintestinal manifestations such as fever and arthralgia were found in over 50% of patients. The most common physical findings were perianal abnormalities (56.3%), mouth ulcers (37.5%) and growth failure (15.6%). Abnormal laboratory findings such as low albumin, raised erythrocyte sedimentation rate, anaemia, thrombocytosis and high C-reactive protein were found in nearly half of the patients. Endoscopic and histological findings showed that a majority of patients (90.6%) also had evidence of inflammation in the upper gastrointestinal tract.
CONCLUSIONPaediatric IBD is on the rise. The higher occurrence in Indians, earlier onset and more florid presentation may suggest different genetic and environmental influences specific to Asian children.
Adolescent ; Age of Onset ; Child ; Child, Preschool ; Colitis, Ulcerative ; diagnosis ; Crohn Disease ; diagnosis ; Environment ; Ethnic Groups ; Female ; Genetic Predisposition to Disease ; Humans ; Inflammation ; Inflammatory Bowel Diseases ; diagnosis ; epidemiology ; ethnology ; therapy ; Male ; Retrospective Studies ; Singapore ; epidemiology ; Treatment Outcome
5.Enteric Fever in a Tertiary Paediatric Hospital: A Retrospective Six-Year Review.
Nur Adila Ahmad HATIB ; Chia Yin CHONG ; Koh Cheng THOON ; Nancy Ws TEE ; Subramania S KRISHNAMOORTHY ; Natalie Wh TAN
Annals of the Academy of Medicine, Singapore 2016;45(7):297-302
INTRODUCTIONEnteric fever is a multisystemic infection which largely affects children. This study aimed to analyse the epidemiology, clinical presentation, treatment and outcome of paediatric enteric fever in Singapore.
MATERIALS AND METHODSA retrospective review of children diagnosed with enteric fever in a tertiary paediatric hospital in Singapore was conducted from January 2006 to January 2012. Patients with positive blood cultures for Salmonella typhi or paratyphi were identified from the microbiology laboratory information system. Data was extracted from their case records.
RESULTSOf 50 enteric fever cases, 86% were due to Salmonella typhi, with 16.3% being multidrug resistant (MDR) strains. Sixty-two percent of S. typhi isolates were of decreased ciprofloxacin susceptibility (DCS). Five cases were both MDR and DCS. The remaining 14% were Salmonella paratyphi A. There were only 3 indigenous cases. Ninety-four percent had travelled to typhoid-endemic countries, 70.2% to the Indian subcontinent and the rest to Indonesia and Malaysia. All patients infected with MDR strains had travelled to the Indian subcontinent. Anaemia was a significant finding in children with typhoid, as compared to paratyphoid fever (P = 0.04). Although all children were previously well, 14% suffered severe complications including shock, pericardial effusion and enterocolitis. None had typhoid vaccination prior to their travel to developing countries.
CONCLUSIONEnteric fever is largely an imported disease in Singapore and has contributed to significant morbidity in children. The use of typhoid vaccine, as well as education on food and water hygiene to children travelling to developing countries, needs to be emphasised.
Adolescent ; Anemia ; epidemiology ; Anti-Bacterial Agents ; therapeutic use ; Child ; Child, Preschool ; Drinking Water ; Drug Resistance, Multiple, Bacterial ; physiology ; Enterocolitis ; epidemiology ; Female ; Food Contamination ; Health Education ; Hospitals, Pediatric ; Humans ; India ; Indonesia ; Infant ; Malaysia ; Male ; Paratyphoid Fever ; drug therapy ; epidemiology ; microbiology ; Pericardial Effusion ; epidemiology ; Retrospective Studies ; Salmonella paratyphi A ; physiology ; Salmonella typhi ; physiology ; Shock ; epidemiology ; Singapore ; epidemiology ; Tertiary Care Centers ; Travel ; Typhoid Fever ; drug therapy ; epidemiology ; microbiology ; prevention & control ; Typhoid-Paratyphoid Vaccines ; therapeutic use
6.Vancomycin-resistant Enterococci in Singaporean hospitals: 5-year results of a multi-centre surveillance programme.
Yiying CAI ; Joey P J CHAN ; Dale Andrew FISHER ; Li Yang HSU ; Tse Hsien KOH ; Prabha KRISHNAN ; Andrea L H KWA ; Thean Yen TAN ; Nancy W S TEE
Annals of the Academy of Medicine, Singapore 2012;41(2):77-81
INTRODUCTIONVancomycin-resistant enterococci (VRE) have emerged as one of the major nosocomial antimicrobial-resistant pathogens globally. In this article, we describe the epidemiology of VRE in Singaporean public hospitals in the 5 years following the major local VRE outbreak in 2005.
MATERIALS AND METHODSA passive laboratory surveillance programme identified non-duplicate VRE isolates from 7 hospitals from 2006 to 2010. Descriptive statistics and time-series analysis was performed on all clinical VRE isolates for each individual hospital as well as for the combined dataset.
RESULTSThere were a total of 418 VRE isolates over 5 years, of which 102 isolates (24.4%) were from clinical cultures. Between 0.4% and 0.7% of all clinical enterococcal isolates were resistant to vancomycin. The overall incidence-density of VRE did not change over time in Singapore despite 2 separate outbreaks in tertiary hospitals in 2009 and 2010. Incidence-density of clinical VRE cases fell in 2 secondary hospitals, while another 2 hospitals experienced no significant VRE infections after 2008.
CONCLUSIONThe prevalence of VRE clinical isolates remains low in Singaporean public sector hospitals. However, the presence of at least 2 outbreaks in separate hospitals over the past 5 years indicates the need for continued vigilance in order to prevent any further increase in VRE prevalence locally.
Anti-Bacterial Agents ; pharmacology ; Cross Infection ; epidemiology ; Enterococcus ; drug effects ; isolation & purification ; Gram-Positive Bacterial Infections ; drug therapy ; Hospitals, Public ; Humans ; Population Surveillance ; Singapore ; epidemiology ; Vancomycin ; therapeutic use ; Vancomycin Resistance ; drug effects
7.An update of paediatric intussusception incidence in Singapore: 1997-2007, 11 years of intussusception surveillance.
Nancy TAN ; Yee-Leong TEOH ; Kong-Boo PHUA ; Seng-Hock QUAK ; Bee-Wah LEE ; Harvey James E L TEO ; Anette JACOBSEN ; Irving Charles BOUDVILLE ; Timothy NG ; Thomas VERSTRAETEN ; Hans Ludwig BOCK
Annals of the Academy of Medicine, Singapore 2009;38(8):690-692
INTRODUCTIONUnderstanding baseline epidemiology of intussusception (IS) in different geographical settings is important for the safety assessment of rotavirus vaccines. This paper presents IS surveillance data from Singapore between 1997 and 2007, including the period between November 2005 and December 2007 when rotavirus vaccines (primarily Rotarix) were available to newborns in Singapore.
MATERIALS AND METHODSCase ascertainment, collection, analyses and presentation of IS data was done as per recommendations of the Brighton Collaboration Working Group. For estimating the IS incidence rate in infants, live births for the years of the study were used as denominators, while for incidence in children age <2 years, the expected numbers of infant deaths occurring between 1 and 2 years of age was deducted from the combined live births for the 2 years, to obtain the denominator.
RESULTSThe incidence of IS among children aged <1 year throughout this 10-year period was higher than the incidence of IS in children between 1 and 2 years of age. In 2005, 2006 and 2007, the incidence of IS per 100,000 was 39.9, 26.4 and 35.6 in children aged <1 year and 26.2, 23.8 and 28.7 in children <2 years.
CONCLUSIONThis IS surveillance study provides reassuring preliminary evidence that there is no increase in the incidence of IS in Singapore after the introduction of rotavirus vaccines (including Rotarix) in Singapore.
Adolescent ; Child ; Child, Preschool ; Female ; Humans ; Incidence ; Infant ; Infant, Newborn ; Intussusception ; epidemiology ; prevention & control ; virology ; Male ; Population Surveillance ; Risk Assessment ; Rotavirus Vaccines ; Singapore ; epidemiology ; Time Factors
8.Antibiotic resistance in gram-negative bacilli: a Singapore perspective.
Thean Yen TAN ; Li Yang HSU ; Tse Hsien KOH ; Lily S Y NG ; Nancy W S TEE ; Prabha KRISHNAN ; Raymond T P LIN ; Roland JUREEN
Annals of the Academy of Medicine, Singapore 2008;37(10):819-825
INTRODUCTIONAntibiotic resistance in gram-negative bacilli is an area of increasing importance. This prospective study was performed to survey antibiotic resistance in Escherichia coli (E. coli), Klebsiella spp., Pseudomonas aeruginosa and Acinetobacter spp. over a 1-year period.
MATERIALS AND METHODSNon-duplicate isolates of E. coli, Klebsiella spp., P. aeruginosa and Acinetobacter spp. were collected from participating Singapore hospitals during defined collection periods in 2006 and 2007. Confirmatory identification and antibiotic susceptibility testing were performed at Changi General Hospital. Minimum inhibitory concentrations (MIC) to a defined panel of antibiotics were determined using microbroth dilution methods. The presence of extended-spectrum beta lactamases and AmpC beta-lactamases in Enterobacteriaceae was determined by phenotypic methods, and susceptibility results were defined using current breakpoints from the Clinical Laboratory Standards Institute (CLSI).
RESULTSSeven hundred and forty-six gram-negative bacilli were received for testing. Resistance to extended-spectrum cephalosporins was present in a third of Enterobacteriaceae isolates, and extended-spectrum beta-lactamases (ESBL) carriage was present in 19.6% and 30.1% of E. coli and Klebsiella pneumoniae, respectively. AmpC enzymes were also detected in 8.5% and 5.6% of E. coli and K. pneumoniae isolates respectively. All Enterobacteriaceae were susceptible to imipenem and meropenem. The most active antibiotics against P. aeruginosa were amikacin, meropenem and piperacillin-tazobactam. A third of P. aeruginosa showed reduced susceptibility to polymyxin B. Carbapenem resistance was significantly higher in Acinetobacter baumannii (70.5%) than in other Acinetobacter species (25.0%). The most active antibiotic against A. baumannii was polymyxin B.
CONCLUSIONAntibiotic resistance is prevalent in gram-negative bacilli isolated from Singapore hospitals. The MIC testing surveillance programme complemented susceptibility data from wider laboratory-based surveillance, and has revealed emerging mechanisms of antibiotic resistance.
Acinetobacter Infections ; drug therapy ; Acinetobacter baumannii ; drug effects ; isolation & purification ; Anti-Bacterial Agents ; pharmacology ; therapeutic use ; Bacterial Proteins ; Drug Resistance, Bacterial ; Escherichia coli ; drug effects ; enzymology ; Hospitals ; Humans ; Klebsiella Infections ; drug therapy ; Klebsiella pneumoniae ; drug effects ; enzymology ; Microbial Sensitivity Tests ; Prospective Studies ; Pseudomonas aeruginosa ; drug effects ; isolation & purification ; Singapore ; beta-Lactamases
9.Risk Factors for Severe Adenovirus Infection in Children during an Outbreak in Singapore.
Veena RAJKUMAR ; Cheryl S M CHIANG ; Jia Meng LOW ; Lin CUI ; Raymond T P LIN ; Nancy W S TEE ; Matthias MAIWALD ; Chia Yin CHONG ; Koh Cheng THOON ; Natalie W H TAN
Annals of the Academy of Medicine, Singapore 2015;44(2):50-59
BACKGROUNDHuman adenoviruses (HAdVs) can cause a variety of human illnesses, with associated temporal and geographic changes in disease incidence. We report the emergence of an outbreak of HAdV infections in Singapore, presumably caused by a change of the predominating type to HAdV-7. We examined the clinical features of children admitted with HAdV infection to 1 institution and the risk factors for severe infection.
MATERIALS AND METHODSThis is a retrospective case-control study of all HAdV-infected children admitted during weeks 1 to 19 in 2013, as identified from laboratory records. A descriptive retrospective analysis of epidemiology, clinical data and the outcome of these children was also performed. Patients with severe infections were defined as cases, those with non-severe infections as controls, and the 2 groups were compared to find possible independent risk factors.
RESULTSEighty-five patients with HAdV infection were studied, including 11 (12.9%) cases and 74 (87.1%) controls. Binary logistic regression showed that cases were more likely to be <2 years old (adjusted OR 10.6, 95% CI, 1.8 to 63.2) and to have significant comorbidities (adjusted OR 19.9, 95% CI, 3.4 to 116.1) compared to controls. The predominant type in 2013 was HAdV-7, which differed from 2011 and 2012, when HAdV-3 was more common. There was a trend towards pneumonia being more common in patients infected with HAdV-7 than in patients infected with other types, although this did not reach statistical significance (OR 2.8, 95% CI, 0.9 to 8.7).
CONCLUSIONThe emergence of HAdV-7 in a population where other HAdV types had circulated previously may have caused the outbreak in Singapore, and this was associated with more serious infections in children. Young age (<2 years) and significant comorbidities were associated with more severe HAdV infection.
Adenoviridae Infections ; epidemiology ; virology ; Adenoviruses, Human ; genetics ; pathogenicity ; Adolescent ; Case-Control Studies ; Child ; Child, Preschool ; Comorbidity ; Disease Outbreaks ; Female ; Humans ; Immunocompromised Host ; Infant ; Male ; Retrospective Studies ; Severity of Illness Index ; Singapore ; epidemiology
10.Zika Virus: An Evolving Public Health Threat.
Chee Fu YUNG ; Chia Yin CHONG ; Kee Thai YEO ; Christina LIEW ; Lee Ching NG ; Natalie Wh TAN ; George Sh YEO ; Nancy Ws TEE ; Raymond Tp LIN ; Thiam Chye TAN ; Victor S RAJADURAI ; Jerry Ky CHAN ; Koh Cheng THOON
Annals of the Academy of Medicine, Singapore 2016;45(4):148-151