Original Article

PWK Chan
Correspondence: Dr Patrick Chan, patrick@ummc.edu.my

ABSTRACT
Objective To determine the risk factors associated with severe viral croup in hospitalised Malaysian children.
Methodology The medical records of children aged less than five years admitted with a diagnosis of viral croup between 1994 and 1999 were reviewed. Severe viral croup was diagnosed in children who had stridor at rest with marked recession associated with central cyanosis or altered level of consciousness. Multivariate logistic regression analysis was performed to identify risk factors associated with severe viral croup.
Results Eighteen (14.7%) of 122 children with viral croup were severe. These children were older (mean age 16.8 +/- 7.2 vs 12.6 +/- 6.6 months, p = 0.01) and had a shorter duration of illness prior to admission (1.7 +/- 0.7 days vs 2.3 +/- 1.4 days, p = 0.03). Age between 12 and 24 months (OR 3.8 95% Cl 1.3, 12.7, p = 0.02) and fever (OR 5.7 95% Cl 2.9, 15.6, p = 0.02) were the only risk factors associated with severe viral croup after multivariate logistic regression analysis. Only three children or 2.5 per 100 children admitted with viral croup required ventilation.
Conclusion Only a small number of children admitted particularly those between 12 to 24 months with fever developed severe viral croup. Recognition of these risk factors provides a guide in selecting children who will most likely benefit from steroid therapy. The overall outcome was nonetheless favourable.

Keywords: severe, viral croup, risk factors
Singapore Med J 2002; 43(3): 124-127

LL Chan, JBK Khoo, CH Thng, WEH Lim, KH Tay, EK Tan, HM Chang, C Chen, MC Wong, KP Tan
Correspondence: Dr L L Chan, gdrcll@sgh.com.sg

ABSTRACT
Cerebrovascular accident (CVA) is a leading cause of death and disability in many countries. Diffusion-weighted (DW) magnetic resonance (MR) imaging has been reported to be useful in the detection of acute strokes and as an investigative tool evaluating the therapeutic effects of neuroprotective and thrombolytic agents. The objectives of this study are to share our experience using the commercially available isotropic DW scan in imaging of acute stroke, assess its usefulness over conventional T2-weighted (T2W) scans in a busy clinical radiology unit and highlight it pitfalls. We found the rapid sub-minute DW technique well suited for ill and restless stroke patients and superior to T2W scans in many ways. It was highly sensitive to acute ischaemic lesions, made lesions easily identifiable and readily differentiated the acute lesion from a background of multiple chronic infarcts. However, there are potential pitfalls in the evaluation of small hyperacute posterior fossa strokes and venous infarcts. The major strength of this MR technique lies in its ability to diagnose hyperacute strokes and thence the potential for therapeutic thrombolysis, but unfortunately patients qualifying for the "therapeutic window" were a minority. More efforts need to be focused on public education in order for this powerful imaging modality to find its true value and contribute to viability of an effective thrombolytic programme.

Keywords: acute stroke, diffusion-weighted MR, T2-weighted MR, strengths, pitfalls
Singapore Med J 2002; 43(3): 118-123

Gurjeet Kaur, S Mahendra Raj
Correspondence: Gurjeet Kaur, gurjeet@kb.usm.my

ABSTRACT
The concordance between endoscopic and histological gastritis was determined in 52 patients referred for upper gastrointestinal endoscopy. The study was conducted in Northeastern Peninsular Malaysia, an area with a low background prevalence of H. pylori infection. Endoscopic and histological gastritis were assessed in accordance with the Sydney System. The results showed poor concordance between endoscopic and histological gastritis even after reclassifying mild endoscopic gastritis as normal. The low prevalence of H. pylori was validated in this study.

Keywords: endoscopic gastritis, histological gastritis, low H. pylori prevalence
Singapore Med J 2002; 43(2): 90-92

R Ponampalam, EJ Otten
Correspondence: R Ponampalam, gaerpo@sgh.gov.sg

ABSTRACT
Background Lithium poisoning is currently managed using a combination of supportive care and urgent haemodialysis in severe cases. Activated charcoal as a gut decontaminant has been found to be ineffective. The use of Sodium Polystyrene Sulphonate (SPS) as an adsorbent has been found to be effective in some studies. However, there have been case reports of gut necrosis and perforation occurring when SPS was used for the treatment of hyperkalaemia in post operative patients or patients with renal failure. Bentonite is a known adsorbent that has been used in the management of paraquat poisonings. The purpose of this study was to determine the ability of bentonite to adsorb lithium.
Method 4.5 g of lithium carbonate was dissolved in 1.5 L of deionised water to form the stock solution. 50 mL aliquots of this stock solution were added to 50 mL of either distilled deionised water (pH 7) or simulated gastric fluid (pH 1.2). Bentonite of either 0.75, 1.5 or 4.5 g was then added to simulate 5:1, 10:1 and 30:1 ratio of adsorbent-to-drug. Controls were made with no bentonite added. The resulting mixture was placed on a shaker for five minutes before being filtered. The filtrate was diluted and batch analysed for lithium using atomic absorption spectrophotometry.
Results Bentonite decreased the concentration of lithium recovered from the filtrate by 20.55% in deionised water compared to 48.09% in simulated gastric fluid at a bentonite:lithium ratio of 30:1 (p value 0.005).
Conclusion This study shows that bentonite is an effective adsorbent for lithium. The effect is enhanced in simulated gastric fluid. In vivo studies are being planned for clinical correlation.

Keywords: Lithium poisoning, Bentonite, Adsorbent
Singapore Med J 2002; 43(2): 86-89

YY Soon, BKH Tan
Correspondence: A/Prof Benny Tan Kwong Huat, phctankh@nus.edu.sg

ABSTRACT
Aim of Study The aim was to investigate the hypoglycemic and anti-oxidant activities of the dried roots of Morinda officinalis in streptozotocin-induced diabetic rats.
Methodology An ethanolic extract of the dried roots of Morinda officinalis and its three fractions (ethyl acetate, n-butanol and water) were obtained. We evaluated the hypoglycemic effects of three different single doses of the crude extract and its fractions in normal and diabetic rats for three hours after administration. Administration of the extract at 150 mg/kg twice daily for 10 days to the diabetic rats was also carried out. The effects of the 10-day treatment on the fasting serum glucose, insulin, total cholesterol, triglycerides, body weight, food intake, fluid intake, hepatic superoxide dismutase (SOD), catalase (CAT) activities, reduced glutathione (GSH), thiobarbituric acid reactive substances (TBARS) and renal TBARS levels were monitored.
Results In the three-hour dose response study, the crude ethanolic extract reduced the fasting serum glucose levels of the diabetic rats significantly at 150 mg/kg but increased those of the normal rats significantly at 600 mg/kg only. The water fraction demonstrated a dose dependent hypoglycemic effect in the diabetic rats whereas the n-butanol fraction increased the fasting serum glucose levels of the diabetic rats significantly at 50 mg/kg only within three hours after administration. The 10-day oral administration of the extract reduced the fasting serum glucose, hepatic and renal TBARS level and significantly increased the hepatic SOD and CAT activities as well as GSH levels.
Conclusion The results indicate that the dried roots of Morinda officinalis possess hypoglycemic, hyperglycemic and anti-oxidant properties.

Keywords: Morinda officinalis, diabetic rat, oxidative stress, hypoglycemic, anti-oxidant
Singapore Med J 2002; 43(2): 77-85

FM Lai, BH Woo, KH Tan, J Huang, ST Lee, BY Tan, BH Tan, SK Chew, GSH Yeo
Correspondence: Dr George S H Yeo, mfm93b@pacific.net.sg

ABSTRACT
Objective To examine the livebirth prevalence rate of Down Syndrome in Singapore from 1993 to 1998.
Design Index cases for the National Birth Defects Register were obtained from all neonatal nurseries in Singapore, all hospital discharge summaries, cytogenetic and pathology reports from all pathology laboratories in Singapore and from the compulsory reporting of all termination of pregnancy cases and stillbirths delivered.
Setting Information for the Register was obtained from case notes retrieved from the medical record offices, antenatal clinics, cytogenetic laboratories, pathology departments and the Registry of Births and Deaths.
Subjects All foetuses with Trisomy 21 diagnosed prenatally together with livebirths and stillbirths with Down Syndrome diagnosed at or after birth were identified from the Registry database.
Main Outcome Measures Prevalence of Down Syndrome
Results From 1993 to 1998, there were 295 Down Syndrome livebirths, four stillbirths and 197 Down Syndrome foetuses aborted. There has been an increasing number of Down Syndrome foetuses diagnosed antenatally ending in termination and this is accompanied by a falling trend in the Down Syndrome livebirth rate in the same years from 1.17 to 0.89 per 1000 total live births. This is despite an expected increase in Down Syndrome livebirth rate obtained by modelling maternal Down Syndrome age-related risks on the maternal age distribution over the years.
Conclusion The livebirth prevalence of Down Syndrome in Singapore has fallen over the years from 1.17/1000 livebirths in 1993 to 0.89/1000 livebirths in 1998 due to antenatal diagnosis and selective termination.

Keywords: Down Syndrome, birth prevalence, national registry, modeling
Singapore Med J 2002; 43(2): 70-76

WC Chow, ASG Lee, YC Seo, CK Tan, HS Ng
Correspondence: Dr Chow Wan Cheng, gm2cwc@sgh.gov.sg

ABSTRACT
The prevalence of hepatitis G virus (HGV) infection in patients with liver diseases in Singapore and its pathogenic role in these patients was studied. One hundred and forty-eight patients who had chronic hepatitis or acute non A-E hepatitis were studied. Presence of HGV RNA was determined by nested polymerase chain reaction of the 5'non-coding region of the virus in all the patients. Hepatitis G IgG antibody to the envelope (E2) antigen was tested with an enzyme immunoassay (Boehringer Mannheim, Singapore) in 76 of them. Most patients (93%) were ethnically Chinese, predominantly males (74%) and chronic hepatitis B (72%) patients. Others had chronic hepatitis C (19%) or cryptogenic cirrhosis (6%). Four patients had acute non A-E hepatitis. HGV RNA and anti-HGenv were present in 3.5% and 8.3% of those with chronic liver disease. HGV infection did not account for any of the acute non A-E hepatitis and most of the cryptogenic cirrhosis.

Keywords:  Hepatitis G, Cryptogenic cirrhosis, Chronic hepatitis, Non A-E hepatitis, Co-infection
Singapore Med J 2002; 43(2): 67-69

NC Tan, MH Chow, P Goh, LG Goh, TK Lim
Correspondence: Dr Tan Ngiap Chuan, Tan.NgiapChuan@singhealth.com.sg

ABSTRACT
There is apparent disparity between the international guidelines on asthma management and the current practice in reality. This can be attributed to both patient's and doctor's factors. This study examines the practice of asthma management by a group of family physicians using a self-administered questionnaire. This comprises questions relating to the main principles of asthma management set by international guidelines. The results showed that majority of the doctors (>90%) in the study reviewed patient's asthma status based on symptoms, educate their patients on types of asthma medications and advised them on allergen avoidance including smoking. Fewer of them (50 to <90%) check trigger factors or inhaled device technique, nocturnal symptoms or ER visits. Even fewer doctors (<50%) bothered to check the patient's peak expiratory flow rate (PEFR) or used spirometry.

Keywords: asthma, international guidelines, PEFR
Singapore Med J 2002; 43(2): 61-66

IYO Leong, DYH Tai
Correspondence: Dr Ian Yi Onn Leong, ian_leong@ttsh.gov.sg

ABSTRACT
Introduction Age has been cited as a predictor of mortality in the intensive care unit (ICU) and suggested as a criterion for rationing resources. We investigated the association of age with both ICU mortality and hospital mortality.
Materials and Methods Patients admitted in 1998 to our Medical ICU (MICU) were retrospectively analysed by stratifying them into four groups: the reference group (55-64 years), the young old (65-74 years), the old old (75-84 years) and the oldest old (more than 85 years). The statistical association of age with ICU mortality and total hospital mortality was determined whilst controlling for the APACHE II(M) score (APACHE II score modified to exclude points for age), the number of organ failures and the presence of a high risk admitting diagnosis.
Results After controlling for disease severity, the ICU mortality and the total hospital mortality were not associated with age. The total hospital mortality was associated with the APACHE II(M) score (Odds ratio (OR), 1.08; 95% Confidence intervals (CI), 1.04-1.12), the number of organ failures (OR, 2.03; CI, 1.50-2.67) and the presence of a high risk diagnosis (OR, 3.50; CI 1.93-6.37). The ICU mortality was also associated with the APACHE II(M) score (OR, 1.07; CI, 1.03-1.11), the number of organ failures (OR, 1.63; CI, 1.26-2.09) and the presence of a high risk diagnosis (OR, 3.22; CI 1.81-5.76).
Conclusion We did not find a statistically significant association between age and mortality. We recommend that age should not be used as a criterion for admission.

Keywords: aged, mortality, intensive care unit, prognosis, APACHE system
Singapore Med J 2002; 43(1): 33-36

CL Goh, L Khoo
Correspondence: Dr C L Goh, nsc@pacific.net.sg

ABSTRACT
Objective To study the efficacy and complications from Unipulse CO2 laser resurfacing system (Nidek, California) for the treatment of scars and wrinkles in patients with Type III and IV skin type.
Methodology This is a prospective study of patients with skin type III and IV who received laser-resurfacing treatment for facial scars and wrinkles. All patients received topical tretinoin 0.025% cream at least two weeks prior to laser resurfacing. Laser resurfacing was carried out under lidocaine 1% nerve blocks with the Unipulse CO2 laser scanning system. The power at tissue was set at 15 watts (fluence = 6.12 J/cm2; spot size = 1.02 mm, frequency = 300 Hz), with a 20% overlap. Lesions around the eyes were resurfaced with one pass. Those on other parts of the face with two to three passes. Patients were assessed up to 12 months. Treatment response (assessed by patient and dermatologist) was graded as "no change" = no improvement, "minimal improvement" = <25% clearance, "moderate improvement" = 25-50% clearance,"good improvement" = 50-75% clearance and "excellent improvement" = >75% clearance. Complications (assessed by dermatologist only) including erythema, hypopigmentation and hyperpigmentation were scored subjectively as none, minimal, mild, moderate and severe.
Results 16 (nine females, seven males) patients were studied. Thirteen patients were treated for acne scars, two patients for wrinkles and one patient for chicken pox scar. Their mean age was 30.7 years (SD = 9.5 years). Fifteen patients had skin type IV and I had skin type III. TREATMENT RESPONSE: Thirteen patients were assessed at six weeks post laser treatment. One (8%) patient had "minimal improvement" (<25%) improvement, 10 (77%) patients had "moderate improvement" (25-50%) and 2 (15%) patients had "moderate improvement" (50-75%) improvement. At six months, 37% had "minimal improvement", 37% had "moderate improvement" and two had "good improvement and one patient with fine wrinkles had "excellent improvement".
Complications  All patients experienced severe erythema at Day 1. Erythema faded over six months. By three months only 22% had minimal erythema and by six months none had erythema. Moderate pigmentation developed in 15% at six weeks. At three months 33% had varying degree of pigmentation. At six months one (12%) patient had residual pigmentation. Only one patient developed mild minimal hypopigmentation at six month, which cleared at 12 months. Another patient developed hypopigmentation at 12 months.
Conclusion CO2 laser resurfacing provides minimal to moderate improvements for scars and wrinkles among Asians with darker skin type. Erythema fades over six months after resurfacing. Post-inflammatory pigmentation is common but tends to clear over six months.

Keywords: Acne scars, wrinkles, cosmetic laser-surgery
Singapore Med J 2002; 43(1): 28-32