Original Article

A Norazah, SM Liew, AGM Kamel, YT Koh, VKE Lim
Correspondence: Dr A Norazah

ABSTRACT
Aim of Study To determine and compare the pulsed-field gel electrophoresis (PFGE) patterns of endemic MRSA strains in 2 major Malaysian hospitals and to compare the PFGE patterns with antibiotypes of the strains studied.
Methods Fifty-six MRSA strains selected randomly between September 1997 and July 1998 from Hospital Queen Elizabeth (HQE) and Hospital Umum Sarawak (HUS) were tested for antimicrobial resistance and DNA fingerprinting was carried out by pulsed-field gel electrophoresis (PFGE) technique.
Results Seven PFGE types were recognised (A, B, C, D, E and F). All 7 PFGE types were observed in HQE while only 2 PFGE types (B, C) were noted in HUS strains. There is a predominance of a single PFGE pattern (type B) in both hospitals, as seen in 46% of HQE strains and 89% of HUS strains. Subtype B2 was the commonest subtype in HQE while subtype B1 predominated in HUS. Strains resistant to fusidic acid and rifampicin exhibited PFGE type F that is unique to HQE. All strains were resistant to penicillin, erythromycin, cotrimoxazole, tetracycline and gentamicin. Strains with the same antibiotic susceptibility pattern can be different PFGE types.
Conclusion Molecular typing of the MRSA by PFGE is a useful tool in the study of endemic strains present in an institution. Strains in HQE were found to be more heterogeneous than HUS strains. Common PFGE types can also be seen in both hospitals suggesting that some of the strains was genetically related and has propagated within and between the 2 hospitals. Our findings also indicate that the relationship between antibiotic susceptibility and PFGE patterns was not close and antibiograms should not be relied upon for typing strains in epidemiological studies. By knowing the DNA fingerprints of the isolates endemic in each hospital, the spread of MRSA with a particular PFGE type can be monitored within and between hospitals.

Keywords: DNA fingerprinting, MRSA, PFGE, Malaysia
Singapore Med J 2001; 42(1): 15-19

G Parker, HL Yap
Correspondence: G Parker

ABSTRACT
Aim of Study To examine for any change in the sex ratio of suicides in Singapore over the last decade.
Methods Data on suicides in Singapore for the decade 1989-98 were examined, both as an overall set and as four age-based sub-groups.
Results The male to female ratio increased significantly over the decade, contributed to most distinctly by changed rates in young adults (ie a group defined as 29-40 years). The changed sex ratio appeared limited to Chinese subjects, where the suicide rate/100,000 population was consistently higher than for the non-Chinese. The changed ratio appeared more to reflect an absolute decrease in female suicides rather than any distinct absolute increase in male suicides.
Conclusion The previous distinct male preponderance in suicide,which had progressively diminished by the early eighties, has become distinct again, but is now seemingly more driven by a disproportionate decline in the absolute rate of suicides in younger females. We speculate on possible social determinants of this intriguing epidemiological trend.

Keywords: suicide, Singapore, sex ratio
Singapore Med J 2001; 42(1): 11-14

SC Ho, ES Tai, PHK Eng, CE Tan, ACK Fok
Correspondence: Dr S C Ho

ABSTRACT
Objective To investigate the effects of Absorbitol on body weight, anthropometry, body composition, blood pressures and lipid profiles in obese, hypercholesterolaemic subjects without dietary restriction.
Design A randomised, double blind. Placebo-controlled study.
Subjects Normal volunteers with no history of chronic illnesses (n=88) who were obese (body fat percentage > 20% in males and > 30% in females) and hypercholesterolaemic (total cholesterol > 5.20 mmol/L). Sixty-eight (72.3%) subjects completed the study.
Intervention After a 4 week run in phase, 4 placebo/Absorbitol (250 mg) capsules were prescribed 3 times a day before meals. Subjects received written information on healthy lifestyle but there was no dietary restriction or monitoring.
Main Outcome Measures Weight, body mass index, lean body mass, waist, hip, blood pressure, fasting lipids and insulin levels were taken at baseline, 4th and 16th week of the study.
Statistical Analysis Performed Analyses were on an intention-to-treat basis. Comparisons between groups were made using Student's t and Mann-Whitney tests for parametric and non-parametric data respectively.
Results There was no significant change in the measured parameters in Absorbitol treated subjects compared to those on placebo, with exception of HDL-cholesterol which increased in the absorbitol group and decreased in the placebo group (p=0.048). The side effects of Absorbitol were also comparable to that of placebo.
Conclusion In the absence of dietary surveillance, Absorbitol does not bring about improvement in weight, anthropometry, body composition, blood pressure or lipid profile.

Keywords: chitosan, Absorbitol, obesity, lipid profile, diet
Singapore Med J 2001; 42(1): 6-10

YC Chan, A Wilder-Smith, BKC Ong, G Kumarasinghe, E Wilder-Smith
Correspondence: Dr E Wilder-Smith, mdcwse@nus.edu.sg

ABSTRACT
Background The objective of this study is to describe the bacteriological, clinical and laboratory features of community acquired bacterial meningitis in adults admitted to a Singapore tertiary-care hospital.
Methods Two hundred sixty-nine cases of meningitis or meningoencephalitis admitted between 1993 and 2000 were identified by their discharge diagnosis codes. All case records except for 57 which could not be retrieved were retrospectively reviewed. Patients less than 14 years or with skull fractures, post-neurosurgery or with indwelling intracranial devices were excluded. Inclusion criteria was a clinical picture compatible with a diagnosis of bacterial meningitis with either (1) positive cerebral-spinal fluid (CSF) cultures or latex coagglutination or CSF neutrophilic pleocytosis accompanied by positive blood cultures or (2) in the absence of positive blood cultures, CSF cultures and latex agglutination, presence of CSF pleocytosis of at least 100 neutrophils per microL.
Results Fifteen "culture-positive" and 11 "culture negative" cases were identified. Six (55%) of the "culture-negative" cases received antibiotics prior to admission. Cultures grew Streptococcus pneumoniae in four cases, three cases each of Group B streptococci and Neisseria meningitides. Listeria monocytogenes and Klebsiella pneumoniae were each seen twice and Streptococcus suis once. All cases of Group B streptococci occurred in the year 1998. Mortality was 19% (n = 5), six developed infections in other sites, three epileptic seizures, three developed hydrocephalus, and two hearing loss.
Conclusion Pathogens are similar to those reported in other studies but for an outbreak of Group B Streptococcus in 1998. There were a high number of "culture-negative" cases which may be due to preceding antibiotic intervention.

Keywords: Adult bacterial meningitis, Community acquired meningitis, South East Asia, Singapore, Coagglutination
Singapore Med J 2002; 43(12): 632-636

K Kumar, KK Tang, J Thomas, C Chumpon
Correspondence: Dr J Thomas, gnsjoh@sgh.com.sg

ABSTRACT
Aim To review the outcome of a consecutive series of patients undergoing carotid endarterectomy in a low volume setting.
Design Retrospective case review.
Patients During an 11-year period we performed 50 elective carotid endarterectomies on patients with symptomatic severe carotid stenosis: Ages of patients raised from 40 to 87 years (mean 68 years), 88% were Chinese, 6% Malay and 4% Indian. Twenty-eight percent had coronary artery disease, 64% hypertension, 27% diabetes mellitus, 50% hyperlipidaemia, and 52% were smokers. None of the patients had prior neck surgery or radiotherapy.
Results There were no deaths in this series of 50 cases. Ninety-eight percent of our patients came through surgery without major neurologic deficit. One patient (2%) suffered a major perioperative stroke. Minor neurologic sequelae included one patient (2%) with a mild non-disabling stroke, two patients (4%) with peri-operative TIA without significant sequelae; two patients (4%) with transient cranial nerve weakness (one vagus, one facial nerve).
Conclusion The surgical outcomes in this series are comparable to that from larger series. Carotid endarterectomy can be safely done in a low volume setting.

Keywords: carotid endarterectomy, low volume
Singapore Med J 2002; 43(12): 628-631

ST Toh, P Lu, M Ong, B Seet
Correspondence: Toh Song Tar, songtar@hotmail.com

ABSTRACT
Aim To determine the prevalence of hearing disorders in Singapore military conscripts and describe the profile of hearing loss and associated risk factors.
Methods Population-based descriptive analysis of randomised cohort of 818 Singapore military conscripts presenting for medical examination, using self-administered questionnaire and pure tone audiometry performed for both ears. Main outcome measures are prevalence rate of hearing loss and relative risk of hearing loss by demographic factors and surrogates for noise exposure.
Results Prevalence of hearing loss was 36.7 per 1,000 (95% CI 24.8, 51.9). Of 30 subjects with hearing loss, 19 (63.3%) had loss at high frequency, 7 (23.3%) at low frequency, and 4 (13.4%) in both ranges. Hearing loss was unilateral in 17 (56.7%) subjects and bilateral in 13 (43.3%). Relative risk of hearing loss did not differ by age group, education level, race or frequency of personal stereo use. Relative risk of hearing loss is higher in subjects with frequent discotheque visits compared to those who never do so (RR = 2.72, 95%CI 1.09, 6.76).
Conclusion The high prevalence of hearing loss in Singapore military conscripts points to the need for routine audiometry screening prior to enlistment. This will be useful in assigning military vocations, in clinical case management, and for assessing cases of noise-induced hearing loss attributable to military service.

Keywords: Hearing loss, audiogram, military, screening
Singapore Med J 2002; 43(12): 622-627

L Pari, M Latha
Correspondence: Dr L Pari, Paribala@sancharnet.in

ABSTRACT
Aim of the Study The main aim was to demonstrate the effects of Cassia auriculata flowers on blood glucose and lipid levels in experimental diabetic rats.
Methodology Aqueous extract of Cassia auriculata flowers was administered orally and different doses of the extract on blood glucose, haemoglobin, glycosylated haemoglobin, serum and tissue lipids, hexokinase and glucose-6-phosphatase in streptozotocin-induced diabetic rats were studied. Glibenclamide was used as standard reference drug.
Results Cassia auriculata flower extract (CFEt), at doses of 0.15, 0.30 and 0.45 g/kg body weight for 30 days, suppressed the elevated blood glucose and lipid levels in diabetic rats. Cassia auriculata at 0.45 g/kg was found to be comparable to glibenclamide.
Conclusion Our findings indicate that the Cassia auriculata flowers possess antihyperlipidaemic effect in addition to antidiabetic activity.

Keywords: Blood glucose, Cassia auriculata, Carbohydrate enzymes, Insulin, Lipids
Singapore Med J 2002; 43(12): 617-621

HC Gan, KH Yoon, KY Fong
Correspondence: Dr Gan Hwa Chau, ganhwachau@yahoo.com

ABSTRACT
Objective To review the clinical outcomes of Systemic Lupus Erythematosus (SLE) patients with biopsy-proven lupus nephritis with regards to the histological features and treatment.
Method Patients (1) with SLE, (2) had renal biopsy in NUH for lupus nephritis, and (3) on follow-up from the period of January 1998 to April 2001, were reviewed.
Result Fifty patients were reviewed with female to male ratio of 4:1. Mean age was 35.4 years. Sixty-eight percent had renal involvement at diagnosis of SLE. At least 50% had other major organ systems involvement. Forty-two patients had WHO Class IV lupus nephritis. Biopsy showed crescents in 17 patients, microangiopathy in 19, and vasculitis in two patients. All patients received prednisolone. Forty-one had IV cyclophosphamide, two had oral cyclophosphamide and seven had cyclosporin A. Azathioprine was used in 41 patients, pulse methylprednisolone in eight, IVIG in four, plasma exchange in three and mycophenolate in two patients.
Outcome Forty-four percent were in complete remission, 26% in partial remission, 34% had relapsed nephritis, 4% had chronic renal failure and 12% progressed to ESRD. There were five deaths.
Conclusion Renal involvement in SLE occurs early in the disease and is associated with other organ systems involvement. Only 44% were in complete remission. Thirty-four percent had relapsed. Renal survival was 88% in this cohort.

Keywords: lupus nephritis, treatment, outcome
Singapore Med J 2002; 43(12): 614-616

FM Abu-Zidan, IG Premadasa
Correspondence: Fikri Abu-Zidan, fabuzidan@uaeu.ac.ae

ABSTRACT
Aim of Study This study was aimed at evaluating the pattern of instructional skills of surgical tutors in a university hospital and the effect of feedback on this pattern.
Method Students who followed three clinical rotations at the Department of Surgery, Mubarak Al-Kabeer Teaching Hospital, Kuwait, responded anonymously to a structured questionnaire on the instructional skills of their tutors immediately after the rotation was completed. The questionnaire included six statements related to teacher-centred instructional skills and six statements related to student-centred instructional skills. The students indicated their perception on a five-point rating scale (very poor, poor, fair, good and very good). A summary of students' opinions was made available to the teachers soon after each rotation.
Results The percentage of good/very good categories was significantly higher in the teacher-centred skills compared with the student-centred skills (median (range), 87.05% (85.9-91.7) compared with 79.6% (76.6-80.6), (p = 0.004, Mann Whitney U test). This difference was significant in the first two rotations (p < 0.005) but not in the third rotation (p=0.59).
Conclusion This study shows that behaviours of teachers which dealt directly with the learner's role in learning received lower emphasis than the teacher-centred activities and that feedback may modify this behaviour.

Keywords: Clinical instruction in surgery, Student-centred learning, Student feedback
Singapore Med J 2002; 43(12): 610-613

M Cheng, KS Tho
Correspondence: Dr M Cheng, mat_cheng@rocketmail.com

ABSTRACT
Introduction Chrisman-Snook reconstruction is a surgical method of treating chronic lateral ankle instability. This study aims to examine the outcome and possible factors including joint hypermobility that may influence the outcome in our local population.
Materials and Methods Twenty-four ankles with chronic lateral ankle instabilities were treated with the Chrisman-Snook reconstruction procedure between May 1995 and November 1997. Fifteen were available for review at an average follow-up period of 35.3 months, ranging from 26 to 51 months. The patients were young and the average age was 24 years. The lateral ligaments were reconstructed by rerouting half the peroneus brevis tendon, based distally, through the lateral malleolus and anchoring it to the calcaneum. Functional results were assessed using the Kaikkonen ankle stability score. Joint hypermobility was assessed by the Beighton et al score.
Results Excellent results were achieved in ten cases, good in four, and fair in one. None had poor results. Best outcomes tended to occur in patients with joint hypermobility. Complications included decreased sensation in a small area of the lateral foot.
Conclusion Chrisman-Snook reconstruction is a surgical option for young patients who have failed conservative treatment for chronic ankle instability. In our local population with a higher incidence of joint hypermobility, it gave good results with few serious complications.

Keywords: Chronic ankle instability, Chrisman-Snook reconstruction, Kaikkonen ankle stability score, Beighton joint hypermobility score
Singapore Med J 2002; 43(12): 605-609