Original Article

BP Khoo, YH Leow
Correspondence: Dr B P Khoo

ABSTRACT
Allopurinol is still an effective uric-acid lowering drug since its introduction in 1963. However it has been frequently incriminated for severe adverse drug reactions. From our retrospective review of 13 inpatients with allopurinol adverse reactions seen over 3 years, fever and rash were the commonest presenting symptoms, occurring several weeks after initiation of the drug. Other associated abnormalities included leukocytosis (62% of patients), eosinophilia (54%), renal impairment (54%) and liver dysfunction (69%). Although 12 patients (92%) met the criteria for allopurinol hypersensitivity syndrome, there was no mortality recorded. The indications for initiating allopurinol therapy were frequently unclear. In view of the severe adverse reactions experienced with allopurinol, we propose that it should only be prescribed when truly indicated.

Keywords: allopurinol, adverse drug reactions, gout and hyperuricemia, multi-organ involvement
Singapore Med J 2000; 41(4): 156-160

A Wong, KH Tan, CS Tee, GSH Yeo
Correspondence: Dr K H Tan

ABSTRACT
Aim of Study The aim of our study was to determine the seroprevalence of cytomegalovirus (CMV), toxoplasma and parvovirus infection in our local antenatal population, and to see the effects, if any, of age, race, parity and nationality on its seroprevalence.
Methodology The sera of 120 consecutive antenatal women seen in KK Women's and Children's Hospital between the period of October 1997 and March 1998 were screened for cytomegalovirus (CMV) IgG, toxoplasma IgG and parvovirus B19 IgG and IgM. An antibody titer greater than 1:32 was regarded as positive.
Results A total of 87.0% of patients were tested seropositive for CMV IgG, 17.2% seropositive for toxoplasma IgG and 30.0% seropositive for parvovirus IgG. There seemed to be a trend of increasing seropositivity with age in all three groups, however only parovirus B19 reached statistical significance. The incidence of all three infections were higher among the Malays, Indians and other races compared to the Chinese.
Conclusion CMV is endemic in our population and hence the most common infection. Toxoplasmosis and parvovirus is relatively low in our population but this implies that a large proportion of our antenatal women are still susceptible to these infections. Prevention of congenital CMV, toxoplasmosis and parvovirus infection is mainly by educating the antenatal population.

Keywords: cytomegalovirus, toxoplasma, parvovirus B19, pregnancy, antenatal
Singapore Med J 2000; 41(4): 151-155

S Sharma, N Abdullah
Correspondence: Dr S Sharma, ssharma@pc.jaring.my

ABSTRACT
Study Design Prospective, randomized, double-blind, placebo-controlled study involving one hundred ASA I-II patients undergoing major gynaecological surgery.
Objective To study anti-emetic efficacy of intravenous (IV) ondansetron (4 mg), droperidol (2.5 mg), metoclopramide (10 mg), and placebo.
Patients and Methods 100ASA physical status I-II undergoing major gynaecological surgery were randomized to receive intravenously (IV), one of the four test drugs 10 minutes before the end of anaesthesia. The incidence of postoperative nausea and vomiting following a standard anaesthetic technique was assessed.
Results A significantly large number of patients who received ondansetron (88%) and droperidol (72%) were free of emetic sequelae when compared to placebo (41%); p < 0.05 (power of this observation is approximately 80% at the given significance level). Metoclopramide was ineffective. Patients given droperidol were significantly more sedated than those receiving ondansetron; p < 0.05. This is not surprising, as the dose of droperidol used in this study was higher than that currently recommended because we found lower doses to be ineffective in controlling nausea and vomiting in this group of patients.
Conclusion It was concluded that, of the drugs studied ondansetron is the best choice for anti-emetic prophylaxis after major gynaecological surgery.

Keywords: pharmacology, ondansetron, droperidol, complications, nausea and vomiting
Singapore Med J 2000; 41(4): 147-150

SC Lee, JEL Wong, YK Kueh
Correspondence: Dr S C Lee

ABSTRACT
A retrospective analysis of 218 patients with non-Hodgkin's lymphoma (NHL) seen at a single institution in Singapore over a ten-year period was conducted. Twenty percent, 56% and 24% of patients had low-, intermediate- and high-grade disease respectively using the Working Formulation, and 25% of patients immunophenotyped had T-cell NHL. Forty-nine percent had primary extranodal disease, with the commonest sites of involvement being the gastrointestinal tract, nasal cavity, and tonsils. 86% and 73% respectively of patients with intermediate and high grade disease received combination chemotherapy as first line treatment, with CHOP being the most commonly used regime. Seventy-four percent of patients with low grade lymphoma received first line chemotherapy, 5% each was treated with radiotherapy or surgery alone, and 21% was treated symptomatically. Patients with low grade B-cell lymphoma had a 5-year survival of 80% and 10-year survival of 42%. One-year survival for intermediate and high grade B-cell lymphoma was 76% and 42%, while 2-year survival was 67% and 42% respectively. 1-, 2-, and 3-year survival for patients with T-cell lymphoma was 67%, 46% and 37% respectively. The difference in survival between low-, intermediate- and high-grade B-cell lymphoma was statistically significant (p = 0.0018 using the log rank test), but that between B- and T-cell lymphoma was not. Using the Cox regression model, International prognostic index, grade and extranodal disease were found to be statistically significant predictors of survival (p = 0.0001, p = 0.0157, p = 0.0343) respectively.

Keywords: Singaporean Asians, non-Hodgkin's lymphoma
Singapore Med J 2000; 41(3): 118-121

LEC Lim, KL Chan, LL Tan, M Sung, MI Loh, PT Straughan
Correspondence: Dr Leslie Lim

ABSTRACT
Patients remanded over a two-year period to Woodbridge Hospital by Court Order were studied retrospectively. Schizophrenia was the most common diagnosis, theft and robbery the most prevalent offences. Males greatly outnumbered females. There were important gender differences, with males tending to commit sexual offences and females, theft and mischief. Males were less likely to be acquainted with their victims but those who caused hurt were more likely to know their victims. Outrage of modesty and theft were more likely to be committed against strangers. The reconviction rate was 26%, with repeat offenders more likely to commit sexual offences and theft. Patients who had previous psychiatric hospitalisation were more likely to be attending follow-up prior to and after release from remand and were more likely to have schizophrenia. Those assessed to be fit to plead were either fined or given jail sentences. Unsoundness of mind and unfitness to plead were associated with further remand in this hospital.

Keywords: court order, remand, criminal offences, victims, reconviction
Singapore Med J 2000; 41(3): 114-117

CT Yeong, TLW Lim, R Lin, SY Se Thoe, N Leong
Correspondence: Dr C T Yeong

ABSTRACT
Genital Chlamydia trachomatis infection has long been recognised as the major cause of pelvic disease and subsequently infertility. The diagnosis of this infection has traditionally relied on tissue culture. The availability of DNA amplification methods like ligase chain reaction promises faster and more sensitive results. This study was conducted to evaluate the prevalence of chlamydial infection in a subfertile population subgroup.
Aim A case control longitudinal study of 100 subfertile women in a tertiary teaching hospital were analyzed for the prevalence of genital Chlamydia trachomatis infection using ligase chain reaction test kit.
Results A prevalence rate of 8% was detected, the majority being 25 years old or less (33.3%), p = 0.007. All patients gave no prior history of abnormal PAP smears, hospitalisation for pelvic inflammatory disease or abnormal vaginal discharge at the time of investigation.
Conclusion Our infertile group of patients has a relatively high incidence of silent genital Chlamydia trachomatis infection. This being highest in the below 25 years old age group. This finding indicates that screening for chlamydia may be necessary for the subfertile couple presenting to clinic. This is especially so if the patient is of the younger age group.

Keywords: chlamydia, infection, subfertile, prevalence, pelvic
Singapore Med J 2000; 41(3): 111-113

SS Nathan, HH Lim, HF See
Correspondence: Dr S S Nathan

ABSTRACT
The tibia is a subcutaneous bone. Operative fixation of tibial fractures is a demanding undertaking. Thirty-five patients with 36 tibial fractures were admitted to our institution between May 1995 and April 1996. The patients were predominantly male (male to female ratio of 4) and the average age of the patients was 31.4 years (range 14 to 67 years). Ten fractures were located in the proximal third, 18 in the middle third and 8 in the distal third. The indications for operation included displaced intra-articular fragments, failed conservative treatment, compartment syndrome, multiple fractures and unstable fracture configuration. Operative procedures included plating in 29 cases and nailing in 7 cases. These patients were reviewed retrospectively and assessed for complications and radiological and functional outcome. The overall results were satisfactory in 88.9% and poor in 11.1%. The complications were reviewed and various factors affecting the incidences analysed. Three deep infections occurred. All were found after discharge from inpatient care. A prolonged interval between admission and surgery as well as high energy of impact are thought to be the main contributing factors.

Keywords: closed tibial fractures, operative treatment
Singapore Med J 2000; 41(3): 107-110

A Leone, A Guidi, G Bertoncini, A Battaglia
Correspondence: Dr A Leone

ABSTRACT
Aim The purpose of this study is to assess the effects of intravenous atropine on blood pressure (BP), systolic BP (SBP) and diastolic BP (DBP), after exposure of healthy volunteers to environmental cigarette smoking.
Methodology Seventeen non-smoking healthy volunteers (11 men and six women), aged from 20 years to 50 years (mean age: 31.3 +/- 8.7), were studied. These subjects received atropine under two conditions: first, in a 60 cubic metres of indoor space unpolluted by cigarette smoke; and second, in the same environment but polluted by 35 ppm carbon monoxide concentration reached by cigarette combustion. BP of each subject was recorded every 15 minutes for two hours by using an Ambulatory Blood Pressure Recorder BR 102.
Results Mean baseline BPs in a smoke-free environment and in a smoking environment were respectively 120 +/- 18 mmHg and 120 +/- 25 mmHg for systolic values, and 81 +/- 6 mmHg and 84 +/- 9 mmHg for diastolic values (P > 0.05). After administration of atropine, mean BPs were respectively 126 (+/- 24)/80(+/- 7) mmHg in a smoke-free environment, and 131 (+/- 14)/ 90(+/- 2) mmHg after exposure to passive smoking (P > 0.05, no statistical significance).
Conclusion Our observations showed that BP varied but without statistically significant changes after acute exposure to passive smoking. However, it is known that any increase in BP leads to higher cardiovascular risks.

Keywords: blood pressure, passive smoke, atropine
Singapore Med J 2000; 41(3): 104-106

YH Ang, SF Wong, KM Chan
Correspondence: Dr Y H Ang

ABSTRACT
Aim To study the death rate of noninstitutionalised elderly after discharge from hospital, describe the causes of death and identify predictive factors of mortality.
Methods Vital status and cause of death of patients was ascertained by linkage to the death registry I year post discharge. Age, sex, race, marital status, housing and class of ward (to reflect socioeconomic status), presence of carer, Elderly Cognitive Assessment Questionnaire (ECAQ) score, Barthel score, presence of depression, number of chronic illnesses and length of stay in the hospital were studied as potential predictive factors for mortality using Cox proportional hazard regression models.
Results Death occurred in 38 out of 113 patients. The commonest causes of death were malignancy (18%) and cerebrovascular disease (18%). Barthel score and length of stay were independent significant predictive factors of mortality. Elderly with low ECAQ score, with carers and from C class wards also had higher mortality although these results were not statistically significant.
Conclusion Post-discharge mortality is high in the elderly. We recommend that further studies be done to determine if amelioration of these predictive factors would lead to decreased mortality or improvement of quality of life.

Keywords: predictive factors, mortality, geriatric, Barthel score, length of stay
Singapore Med J 2000; 41(3): 98-102

HC Tan, YT Lim, TT Lim, A Cheng, BL Chia
Correspondence: Dr H C Tan

ABSTRACT
Background Abciximab, a monoclonal antibody to platelet glycoprotein IIb/IIIa receptor, has been shown to be effective in reducing ischemic complications after coronary angioplasty in recent trials. However, little is known about its efficacy and safety when used in Asian patients.
Methodology Based on our abciximab registry, we performed a retrospective analysis of 115 Asian patients who received the antiplatelet agent while undergoing percutaneous coronary intervention in our centre. They constituted 18.4% of the total number of patients undergoing percutaneous revascularisation during the corresponding period. The majority of the patients were males (84%). The mean age of the cohort was 54 and the mean weight was 70 kg. The ethnic composition of the study population was: Chinese 54%, Indians 21%, Malays 19% and Others 6%. All patients received aspirin 100 mg and weight-adjusted heparin before the procedure. Abciximab may be administered on a preplanned basis prior to the procedure or be given as a 'bailout' strategy.
Results There was a high clinical success rate of 95.8% and low incidence of ischemic complications when abciximab was given during coronary angioplasty. There were 0% Q myocardial infarction, 3.3% non-Q myocardial infarction and 0.8% death in our series. Bleeding complications were uncommon at 7.6%, predominantly involving the groin and gingiva. Thrombocytopenia occurred in 5.8% of patients. Abciximab was noted to increase the procedural activated clotting time (ACT) by 38 seconds when given concomitantly with heparin. The mean maximal procedural ACT achieved was 323 +/- 51 seconds.
Conclusion Abciximab may be used safely and efficaciously in Asian patients undergoing coronary angioplasty. The drug confers protection against ischemic complications during the procedure whether it is administered electively or as a 'bailout'. There is however, a need to redefine the heparin regime for our patients, given the high ACT obtained when abciximab is administered.

Keywords: abciximab, coronary angioplasty
Singapore Med J 2000; 41(2): 69-73