Original Article

Chan SH, Tan PTN, Han HH, Bock HL
Correspondence: Dr Hans L Bock, hans.l.bock@gsk.com

ABSTRACT
Introduction Older children and adults, susceptible to pertussis because of waning immunity, may serve as a reservoir of infection, leading to severe disease among young unvaccinated infants. Booster diphtheria-tetanus-acellular pertussis (dTpa) vaccination in older age groups is rare in Singapore, one reason being the increase in reactogenicity with each successive dose. The aim of this study was to assess the immunogenicity, safety and reactogenicity of a reduced antigen, combined dTpa vaccine as a single booster dose in healthy adults aged 18 years or older.
Methods A total of 150 healthy adults, 18 to 60 years of age, received a single dose of GlaxoSmithKline Biologicals' dTpa vaccine with reduced content for diphtheria and pertussis, with measurement of pre- and post-vaccination antibody titres.
Results Prior to vaccination, 71.6 percent and 92.6 percent of the subjects had anti-diphtheria and anti-tetanus antibody levels greater than or equal to 0.1 IU/mL, respectively. 46.7 percent, 98.5 percent and 44.4 percent of subjects were seropositive for pertussis toxin (PT), filamentous haemagglutinin (FHA) and pertactin (PRN) antibodies, respectively. One month after vaccination, there was an increase in geometric mean titres from pre-vaccination to post-vaccination blood samples for anti-diphtheria (greater than seven-fold), anti-tetanus (greater than five-fold), anti-PT (greater than 11-fold), anti- FHA (greater than 25-fold) and anti-PRN (greater than 31-fold) antibodies. Solicited grade three local symptoms (pain, redness and swelling) were reported in 14.1 percent, 8.1 percent and 10.4 percent of subjects, respectively. No serious adverse events were reported.
Conclusion In summary, the dTpa vaccine is immunogenic, safe and well-tolerated in Singaporean adults.

Keywords: diphtheria, diphtheria-tetanus-acellular pertussis vaccines, immunisation, pertussis, tetanus, whooping cough
Singapore Med J 2006; 47(4): 286-290

Das RN, Chandrashekhar TS, Joshi HS, Gurung M, Shrestha N, Shivananda PG
Correspondence: Dr T S Chandrashekhar, chandrashekharats@yahoo.com

ABSTRACT
Introduction Urinary tract infection (UTI) is the most common nosocomial infection among hospitalised patients. Area-specific monitoring studies aimed to gain knowledge about the type of pathogens responsible for UTIs and their resistance patterns may help the clinician to choose the correct empirical treatment. Recent reports have shown increasing resistance to commonly-used antibiotics. We aimed to study the antibiotic resistance pattern of the urinary pathogens isolated from hospitalised patients.
Methods Three urine samples were collected by the mid-stream "clean catch" method from 1,680 clinically-suspected cases of urinary tract infections from inpatients of various clinical departments during one year. The samples were tested microbiologically by standard procedures. Antibiotic susceptibility of the isolated pathogens was tested for commonly-used antibiotics by Kirby-Bauer technique according to NCCLS guidelines.
Results Significant bacteriuria was present in 71.7 percent of the samples, 17 percent were sterile, 4.8 percent showed insignificant bacteriuria, and 6.5 percent non-pathogenic bacteriuria. The most common pathogens isolated were Escherichia coli (59.4 percent), Klebsiella spp (15.7 percent) and Enterococcus faecalis (8.1 percent). The mean susceptibility was high for amikacin (87.2 percent), ciprofloxacin (74.8 percent), ceftazidime (71.5 percent) and gentamicin (70.4 percent) but low for nitrofurantoin (35 percent), cephalexin (49.7 percent) and ampicillin (50.5 percent). Escherichia coli was found to be most susceptible to amikacin (98 percent) followed by gentamicin (87.9 percent), ceftazidime (80.8 percent), norfloxacin (78.4 percent) and cotrimoxazole (77.9 percent).
Conclusion A high isolation rate of pathogens from urine samples of clinically-suspected UTI shows a good correlation between clinical findings and microbiological methods. The antibiotics commonly used in UTIs are less effective. Since the present study was a cross-sectional study, regular monitoring is required to establish reliable information about resistance pattern of urinary pathogens for optimal empirical therapy of patients with nosocomial UTIs.

Keywords: antibiotics, bacteriuria, nosocomial infection, urinary tract infection
Singapore Med J 2006; 47(4): 281-285

Goh PL, Lee SW, Wong EH
Correspondence: Dr. Goh Pak Liang, pak_liang_goh@cgh.com.sg

ABSTRACT
Introduction Children commonly present with fever without source yet there is no reliable and consistent method of identifying those at risk of serious bacterial infection. In this study, we sought to identify predictors of serious bacterial infection in children aged between three to 36 months with fever without source.
Methods Inpatient records of all children aged three to 36 months admitted from the Emergency Department of Singapore's main paediatric hospital between October 2001 to February 2002 with International Classification of Diseases (ninth revision) diagnosis codes 038 (septicaemia), 079 (viral fever), or 780 (pyrexia of unknown origin), were retrieved and reviewed. Patients identified as having fever without source were enrolled.
Results Of 86 enrolled children, 17 (19.8 percent) had serious bacterial infection. Duration of fever and white blood cell count were found to be significant predictors. Children with white blood cell count equal to or greater than 16,000/cubic mm had 6.9 times (95 percent confidence interval [CI] is 1.7 to 28.4) increased risk of serious bacterial infection, while children with fever of duration exceeding three days before presentation had 3.8 times (95 percent CI is 1.1 to 13.1) increased risk of serious bacterial infection. A combination of white blood cell count less than 16,000/cubic mm and duration of fever three days or less had a negative predictive value of 1.0 (95 percent CI is 0.88 to 1.0) and a sensitivity of 1.0 (95 percent CI is 0.82 to 1.0).
Conclusion The two identified predictors offer an estimate of the risk of serious bacterial infection in children aged three to 36 months with fever without source.

Keywords: bacteraemia, children, fever of unknown diagnosis, fever without source, white blood cells
Singapore Med J 2006; 47(4): 276-280

Loganathan A, Arumainathan UD, Raman R
Correspondence: Dr A Loganathan, drloga68@yahoo.co.uk

ABSTRACT
Introduction Diagnosis and treatment of acute tonsillitis are one of the most common problems seen at an otorhinolaryngology clinic in both adult and paediatric populations. Much has been written about bacteriology of recurrent tonsillitis but it remains a controversial topic. Despite the fact that tonsillitis is so common, consensus seems to be lacking as to the main causative organism and the differences between children and adults. The tonsillar core bacteriology of 233 patients with recurrent tonsillitis who underwent tonsillectomy from January 2000 to June 2003 is presented.
Methods The patient population was divided into two groups, namely: the paediatric group and the adult group. 132 patients, whose age was more than 12 years, were in the adult group. 101 patients aged between two and 12 years, were in the paediatric group. The bacteriology of the children and adults were tabulated according to their species, and were compared.
Results 138 patients grew single pathogenic bacteria in their tonsillar core culture, 52 grew two different pathogenic bacteria, and the rest (43) grew normal bacterial flora. Staphylococcus aureus was the most commonly-isolated bacterium and accounted for 40.9 percent of the total cultures isolated; its prevalence was the same in the adults and children. Beta-haemolytic Streptococcus was isolated in 23 percent of subjects, and was predominantly from group A (Streptococcus pyogens). Group A beta-haemolytic Streptococci was more prevalent in children. Pseudomonas aeruginosa, which rarely cause pathogenicity in tonsils, was cultured from nine (3.8 percent) of our study subjects.
Conclusion This study showed that Staphylococcus aureus is the most common pathogenic bacteria cultured both in adults and children. Klebsiella pneumonia, Streptococcus pneumonia, Escherichia coli and Enterobacter are more prevalent in adults. Haemophilus influenza and Streptococcus pyogens are more prevalent in children. Pseudomonas aeruginosa is not a rare causative organism in recurrent tonsillitis. Since the mechanism of activation of infection in recurrent tonsillitis is unknown, knowing the bacteriology does not help us to treat the disease. However, it may be a stepping stone to eventually understanding whether the bacteria play a role in reactivating recurrent infections. From previous and current studies, there is no relationship between bacteriology and recurrent infections.

Keywords: bacteriology, pathogenic bacteria, Staphylococcus aureus, tonsillitis, tonsillar core culture
Singapore Med J 2006; 47(4): 271-275

Chan GC, Tang SF
Correspondence: Dr Giin-Cherng Chan Klinik Cheng, dr_changc@yahoo.com

ABSTRACT
Introduction A study was carried out in a primary healthcare clinic in the Hulu Langat district of Malaysia to assess the parental knowledge, attitudes and antibiotic use for common childhood acute upper respiratory tract infection (URTI).
Methods A cross-sectional study involving 421 parents, who were surveyed by using an interviewer-administered questionnaire, from April to June 2001.
Results Approximately 59 percent of parents from this study believed that weather was the main cause of acute URTI of their children, 13 percent thought it was due to food, and only about 27 percent said it was caused by germs. Nearly 68 percent, 69 percent and 76 percent of them believed that antibiotics was helpful in treating the common cold, cough and fever, respectively. 29 percent of parents who thought that their child with acute URTI needed antibiotics were not prescribed with any. On the other hand, 17 percent believed that antibiotics were unnecessary when prescribed. 28 percent of parents had requested for antibiotics, and 93 percent received what they requested for their child with acute URTI. About 31 percent of parents who did not request any antibiotics claimed that private general practitioners habitually prescribed antibiotics. The antibiotic compliance was poor with only 74 percent completing the entire course, with 85 percent of them stopping once they improved symptomatically. 15 percent of parents gave "leftover" antibiotics, 24 percent gave "shared" antibiotics, and 5.5 percent bought antibiotics for their child with acute URTI without consulting a doctor.
Conclusion This study shows that parents often have inadequate knowledge and misconceptions on antibiotic use for acute URTI in children. Improved parental education may reduce unnecessary antibiotic prescription and antimicrobial resistance in the community.

Keywords: antibiotics, children, parental attitude, parental knowledge, upper respiratory tract infections
Singapore Med J 2006; 47(4): 266-270

Shankar PR, Upadhyay DK, Subish P, Dubey AK, Mishra P
Correspondence: Dr P Ravi Shankar, ravi_p_shankar001@hotmail.com

ABSTRACT
Introduction Infants and children constitute a large proportion of the population in developing countries. In Nepal, studies on drug use patterns in the paediatric age group are lacking in hospitals in the western region. The present study was carried out to obtain demographical information and information on the prescribing patterns of drugs. The antibiotic sensitivity patterns of commonly-isolated micro-organisms and the mean cost of drugs were obtained.
Methods The study was carried out over a four-month period (December 1, 2003 to March 31, 2004) at the Manipal Teaching Hospital, a tertiary care hospital in Pokhara, western Nepal. The case records of patients discharged from the paediatrics ward during the study period were analysed. Mean number of drugs prescribed was calculated. The percentage of admissions that were prescribed antibiotics was determined.
Results 356 patients were admitted during the study period, of which 228 were male. The median duration of hospitalisation was four days. The mean number of drugs prescribed per admission was 4.5. 789 drugs (48.9 percent) were prescribed by the parenteral route. Antibiotics were prescribed in 249 admissions (69.9 percent). Staphylococcus aureus, Escherichia coli, and Acinetobacter species were the common organisms isolated, and were resistant in some cases to the commonly-used antibiotics. The mean (+/- standard deviation) cost of drugs per admission was 5.4 (+/-1.6) US dollars.
Conclusion Prescribing by generic name should be encouraged. Use of parenteral antibiotics was high and route conversion programmes should be instituted. Use of antibiotics for predominantly viral infections should be reduced. Treatment guidelines for common conditions should be formulated.

Keywords: antibiotics, children, drug prescription, drug utilisation, parenteral drugs
Singapore Med J 2006; 47(4): 261-265

Prabhakaran L, Lim G, Abisheganaden J, Chee CBE, Choo YM
Correspondence: Ms Lathy Prabhakaran, lathy_prabhakaran@ttsh.com.sg

ABSTRACT
Introduction We conducted a study to assess the impact of an asthma education programme (AEP) on knowledge of asthma and medication, compliance to treatment and inhaler technique, emergency department visits and hospital re-admissions.
Methods Patients hospitalised for asthma exacerbation were administered a questionnaire to test their baseline knowledge and beliefs on asthma, its medications and their compliance to treatment. Their inhaler technique was assessed. They then underwent an AEP consisting of two individualised education sessions. Re-testing was performed after three months. Per protocol approach and McNemar's test was used to analyse the statistical significance of the change in the pre- and post-AEP test scores. Hospital administrative data were used to determine the number of ED visits and hospital admissions pre- and post-AEP.
Results Among the 67 patients who completed the two-phase AEP, there was significant improvement in some knowledge aspects (ability to identify rescue medication [p-value is 0.031], that different stimuli can trigger asthma symptoms [p-value is 0.016], that a peak flow meter is used for monitoring asthma [p-value is 0.004], that asthma symptoms are caused by airway swelling/narrowing [p-value is less than 0.001], that steroid inhaler are to be used daily as preventive therapy [p-value is less than 0.001], in self-reported inhaler compliance (number of puffs per administration [p-value is less than 0.001] and per day [p-value is less than 0.001]), and in inhaler technique [p-value is 0.001]. There was also significant reduction in emergency department attendances (p-value is less than 0.001) and hospital admissions (p-value is less than 0.001) among all 97 subjects over a one-year period.
Conclusion This study demonstrated the effectiveness of an AEP in patients hospitalised for asthma exacerbation.

Keywords: asthma, asthma education programme, emergency department, inhaler, patient knowledge
Singapore Med J 2006; 47(3): 225-231

Ang YH, Au SYL, Yap LKP, Ee CH
Correspondence: Dr Ang Yan Hoon, yan_hoon_ang@alexhosp.com.sg

ABSTRACT
Introduction This study aims to determine if risk factors present on admission to the nursing home could be predictive of later functional decline and to determine the causes of decline.
Methods This is a retrospective case-control study conducted in 2000 at a voluntary welfare nursing home. Functional decline was defined as deterioration in two or more of the five activities of daily living (ADLs), namely: mobility, toileting, bathing, dressing and feeding, from the time of admission to the study period. Potential risk factors for decline studied were: age, sex, marital status, number of medical diagnoses and medications, types of medical diagnoses, and the presence of dementia on admission to the home. Causes of decline were categorised as (A) Development of new illness, (B) Progression of chronic illness, or (C) Both of the above.
Results 36 out of 103 residents had functional decline. On analysis, univariate and multivariable logistic regression models, adjusted for length of stay, yielded the same significant risk factors for decline, namely: age (p-value is 0.02) and dementia (p-value is 0.04). Majority of decline (78 percent) was due to progression of chronic illnesses, most commonly dementia (15 out of 36), eight percent were due to acute illness (stroke), and 14 percent were due to both. In January 2003, 18 out of the 36 residents who declined had died.
Conclusion Functional decline is common in the nursing home. More attention should be paid to the older residents and those with dementia, right from the point of admission.

Keywords: activities of daily living, dementia, elderly, functional decline, nursing home
Singapore Med J 2006; 47(3): 219-224

Kong KH, Yang SY
Correspondence: Dr Kong Keng He, keng_he_kong@ttsh.com.sg

ABSTRACT
Introduction To assess health-related quality of life (HRQOL) among chronic stroke survivors and factors associated with it.
Methods Cross-sectional survey study of patients who had survived one year or more after a stroke. Subjects consisted of stroke patients attending the outpatient clinic of a rehabilitation centre. HRQOL was assessed using the Medical Outcomes 36-Item Short-Form Health Survey (SF-36), functional status using the Modified Barthel Index (MBI), and mood using the Beck's Depression Inventory (BDI).
Results A total of 100 patients (63 men and 37 women, mean age 60.7 +/-10.8 years) were interviewed at an average of 22.2 +/-14.5 months post-stroke. The mean MBI was 88.9 +/-17.9, and the prevalence of depression 24%. 50 percent of patients needed varying degrees of care for their activities of daily living. The SF-36 scores of the patients were comparable to that of the general population except for the domain of physical function, which was much lower (23.9 versus 83.4). Age, sex, post-stroke duration, MBI score and side of hemiplegia were not associated with HRQOL. Depressed patients however had significantly lower SF-36 scores across all domains except for that of physical function and bodily pain (p-value is less than 0.001).
Conclusion A significant proportion of chronic stroke survivors attending the rehabilitation clinic continue to face limitations in their physical activities. In addition, almost 30 percent of these survivors have depression that affects their HRQOL adversely.

Keywords: cerebrovascular accident, depression, quality of life, stroke, stroke rehabilitation
Singapore Med J 2006; 47(3): 213-218

Ko KF, Sheppard L
Correspondence: Dr Ko Kwai Fu, kokwaifu@yahoo.com.hk

ABSTRACT
Introduction There are significant differences in stroke patterns and risk factors for cerebrovascular disease between Chinese subjects and Caucasians. The outcome of stroke unit care in a Chinese population has not been described in the medical literature. The present study aims to evaluate the outcome of stroke unit care in Chinese subjects.
Methods By prospective comparative research, Chinese patients treated in the stroke unit were group-matched with those treated in the general medical ward by age, gender, premorbid functional status (by the Barthel Index), National Institute of Health Stroke Scale score, and stroke types. From April 2001 to April 2002, a total of 188 patients in the stroke unit group and 177 patients in the general ward group were recruited in the study. The main outcome measures included mortality at 28 and 120 days, and the length of inpatient stay.
Results Stroke unit care significantly reduced mortality of patients with acute stroke after 28 and 120 days. After 28 days, mortality was 3.3 percent and 17.2 percent for the stroke unit group and general ward group, respectively (p-value is equal to or less than 0.01); whereas after 120 days, mortality was 5.0 percent and 24.7 percent for the stroke unit group and general ward group, respectively (p-value is equal to or less than 0.001). The stroke unit care was demonstrated, by logistic regression analysis, to have contributed to the reduction of mortality at 120 days (p-value is 0.014). At 28 days, there was only a trend for stroke unit care to contribute to the reduction of mortality by logistic regression analysis (p-value is 0.067). By Kaplan-Meier survival curves (log rank statistic is 10.46, p-value is 0.001) and a Cox regression (hazard ratio 0.253, 95 percent confidence interval 0.085 to 0.754, p-value is 0.014), the stroke unit care was further found to reduce mortality significantly. The mean length of inpatient stay of the stroke unit group was 37.1 days, while that of the general medical ward group was 69.3 days (p-value is equal to or less than 0.001).
Conclusion Chinese subjects receiving comprehensive stroke unit care are associated with less mortality and shorter length of hospital stay than those having conventional care in general medical wards.

Keywords: cerebrovascular disorders, general wards, outcome assessment, stroke, stroke unit
Singapore Med J 2006; 47(3): 208-212