Original Article

Viswambharan N, Suganthi R, Simon AM, Manonayaki S
Correspondence: Dr Suganthi R, sugantham2000@gmail.com

ABSTRACT
Introduction Y chromosome microdeletions are common in about 10-15 percent of men with azoospermia or severe oligospermia. These microdeletions are too small to be detected by karyotyping. They can be easily identified using polymerase chain reaction (PCR). Most of the microdeletions that cause azoospermia or oligospermia occur in the non-overlapping regions of the long arm of the Y chromosome. These regions, also called azoospermia factor regions (AZF), are responsible for spermatogenesis. The loci are termed AZFa, AZFb and AZFc from proximal to distal Yq. Several genes located in AZF regions for spermatogenesis is viewed as "AZF candidate genes". This study aims at PCR-based rapid analysis of Y chromosome microdeletion, which is a cause for male infertility.
Methods PCR amplification using Y-specific STS (sequence tagged sites) of AZF regions for AZFa: DBY and sY84, AZFb: RBM1 and sY127, and AZFc: BPY2 and sY254, were conducted.
Results Of the 30 infertile men, 17 were azoospermic and 13 were severely oligospermic. Severe oligospermia was diagnosed in those patients who produced only one-third the concentrations of the sperm of that found in fertile men. Four patients showed a deletion of one or more STS. Two patients had complete deletion of AZFc loci, three patients had complete deletion of AZFa loci and two patients had complete deletion of AZFb loci.
Conclusion The frequency involving the microdeletion in the AZF region was found in four out of 30 azoospermic and severely oligospermic infertile men, i.e. 13.3 percent of the total deletions.

Keywords: azoospermia factor, gene mapping, male infertility; Y chromosome microdeletion
Singapore Med J 2007; 48(12): 1140–1142

Owlia MB, Sami R, Akhondi M, Salimzadeh A
Correspondence: Dr Mohammad Bagher Owlia, mbowlia2@yahoo.com; owlia@ssu.ac.ir

ABSTRACT
Introduction Cryoglobulins are found in a wide spectrum of disorders but are often transient and without clinical implications. The so-called essential mixed cryoglobulinaemia shows a striking association with hepatitis C virus (HCV) infection (greater than 90 percent). Type II cryoglobulinaemia is the major extrahepatic manifestation of HCV infection. This study aims to investigate the frequency of cryoglobulinaemia in HCV-positive patients in central Iran.
Methods 50 HCV-positive patients referred to the Shaheed Sadoughi Hospital in Yazd, Iran from May 2004 to December 2005, were included in the study. Their sera were assessed for cryoglobulins. The sera were separated by centrifugation at 37 degrees Celsius and placed in a four degrees Celsius refrigerator in two tubes, one simple and the other, a Wintrobe tube, to see if precipitation occurs during a 48-hour up to a seven-day period.
Results In this study, 50 HCV positive patients were evaluated. Only two patients were female. Mean age was 32 years (ranging from 17 to 52 years). In eight patients, the cryoglobulin test was positive. In seven patients, the test became positive less than 72 hours after sampling. Only one patient who was positive for cryoglobulinaemia, had clinical manifestation of frank vasculitis.
Conclusion The prevalence of cryoglobulinaemia in Iran may be lower than other areas, and it may be due to a higher prevalence of cryoglobulinaemia in females and lower prevalence of cryoglobulinaemia in HCV genotype-1a. Most of the cases in our study were male and the more prevalent genotype in Iran is genotype-1a.

Keywords: cryoglobulinaemia, hepatitis C, vasculitis
Singapore Med J 2007; 48(12): 1136–1139

Yeo KQ, Yeo EMN
Correspondence: Dr Yeo Khee Quan, yeo@yeoortho.qmax.com.sg

ABSTRACT
Introduction The study compares the results of open release of carpal tunnel syndrome with a release done with a proprietary instrument, the KnifeLight®, which uses a minimal access approach.
Methods A retrospective study was conducted on two groups of patients operated on by the same surgeon between January 1998 and August 2002. All cases presented with numbness of six months duration or more, and a positive Phalen’s test. Open carpal tunnel release was done in the first group of 26 consecutive patients before the KnifeLight® was introduced in January 2000. The KnifeLight® technique was used in a second consecutive group of 49 patients. In two patients, the KnifeLight® procedure was abandoned because the median nerve could not be safely separated from the transverse carpal ligament.
Results The two groups were shown to be comparable with respect to clinical presentation and nerve conduction studies. There was no complication in both groups. However, no advantage could be demonstrated in the use of the KnifeLight® procedure as compared to the open procedure in respect to improvement in pain, numbness or patient satisfaction. The study also showed that the severity of nerve conduction changes is not related to the severity of numbness. It is also not a good guide to the improvement of numbness and patient satisfaction after the operation.
Conclusion The method was found to be acceptable to patients as an office procedure. The cost of doing either procedure is reduced when done as an office procedure, but there is a cost incurred in the use of the KnifeLight® instrument.

Keywords: Carpal tunnel release, KnifeLight®, minimal access surgery, nerve conduction changes, office surgery
Singapore Med J 2007; 48(12): 1131–1135

Namwongprom S, Ekmahachai M, Vilasdechanon N, Chankaew N, Boonyaprapa S, Chitapanarux T
Correspondence: Dr Sirianong Namwongprom, snamwong@mail.med.cmu.ac.th

ABSTRACT
Introduction Variceal haemorrhage is a potentially life-threatening complication in cirrhotic patients. Identification of patients at high risk for bleeding is particularly important. The aim of this study was to determine the clinical usefulness of per-rectal portal scintigraphy (PPS) in the evaluation of the severity of portal hypertension in cirrhotic patients, in terms of correlation between cirrhosis and the parameters of hepatic functional reserve, and identifying the difference of the portal shunt index (PSI) of the bleeding oesophageal variceal (BEV) patients and non-BEV patients.
Methods Portal circulations in 67 patients with cirrhosis and oesophageal varices were evaluated by Tc-99m pertechnetate PPS. Tc-99m pertechnetate (550 MBq) was instilled into the upper rectum, and dynamic images of upper abdomen were taken. Radioactivity curves for the liver and the heart were generated sequentially. Through the analysis of these curves, the PSI was determined.
Results The results, expressed as PSI, were: 11.4 +/- 98.4 percent (mean 66.8) in all 67 cirrhotic patients, 56.4 +/- 27.1 percent in cirrhotic patients without history of BEV, and 74.9 +/- 13.6 percent in cirrhotic patients with history of BEV. The PSI was significantly lower in cirrhotic patients without BEV than those with BEV (p-value equals 0.001). The PSI calculated with this method was correlated with the serum albumin, the serum bilirubin, the prothrombin time, and the Child-Turcotte-Pugh score.
Conclusion Tc-99m pertechnetate PPS has clinical usefulness as a noninvasive method of choice for quantitatively evaluating the severity of portal hypertension in cirrhotic patients.

Keywords: liver cirrhosis, oesophageal varices, per-rectal portal scintigraphy, portal hypertension, porto-systemic shunt index
Singapore Med J 2007; 48(12): 1125–1130

Tang HC, Wong A, Wong P, Chua TSJ, Koh TH, Lim ST
Correspondence: Dr Tang Hak Chiaw, tang_hak_chiaw@nhc.com.sg

ABSTRACT
Introduction Acute myocardial infarction (AMI) due to left main coronary artery (LMCA) occlusion carries a grave prognosis. Large series reporting on the outcome of emergency revascularisation (percutaneous or surgical) of acute LMCA occlusion have been scarce. We seek to identify, in our local population, the clinical presentation and outcome of this group of patients.
Methods From January 2000 to December 2005, a total of 1,539 patients underwent primary percutaneous coronary angioplasty for AMI in our institution. 11 patients (0.8 percent) underwent percutaneous intervention to the LMCA. These patients became the subjects of our study. Data on demography, clinical features and outcome was collected from all in-hospital and clinical notes. One sub-investigator, who was blinded to the study outcome, assessed the angiographical features.
Results The overall inpatient mortality was 82 percent (9 out of 11). Nine out of 11 patients presented with cardiogenic shock. All patients presented with shock died during the hospital stay. All patients required intra-aortic balloon counter pulsation insertion. Of the two patients who survived till discharge, one had angioplasty followed by bypass surgery. The remaining one had angioplasty and stenting to the left main artery. Both survivors have been doing well without further major adverse cardiac event after an average of 64 months of follow-up.
Conclusion Percutaneous revascularisation of acute LMCA occlusion is feasible and the best outcome is seen in stable patients. Prognosis is still poor in patients with unfavourable clinical features.

Keywords: acute myocardial infarction, emergency coronary revascularisation, intra-aortic balloon counter pulsation, left main coronary artery occlusion, primary percutaneous coronary angioplasty 
Singapore Med J 2007; 48(12): 1122–1124

Lee YHD, Lim YW, Ling PS, Tan YY, Cheong M, Lam KS
Correspondence: Dr Lee Yee Han Dave, davelyh@singnet.com.sg

ABSTRACT
Introduction Calcium supplementation and pharmacotherapy are recommended in the preventive management of osteoporosis. Many previous studies report of underdiagnosis and undertreatment of osteoporosis among elderly patients with hip fractures. We undertook this study to determine the dietary calcium levels in our local elderly population who were admitted with hip fractures.
Methods 77 patients, between the ages of 60 and 98 years of age, and admitted to our department between January 2001 and September 2001 for hip fractures, were studied. The dietary calcium intakes of these patients were determined by a food frequency questionnaire and a detailed diet history. Bone mineral density (BMD) studies were performed on 55 of these patients to confirm the diagnosis of osteoporosis.
Results The mean daily calcium intake was found to be 650 mg. Only six of our hip fracture patients (7.8 percent) had a daily calcium intake above the recommended levels of 1,000 mg per day. For the 55 patients who had BMD performed, only one patient had a BMD within the normal range. 34 patients (64.2 percent) had hip T-scores in the osteoporotic range and 18 patients (33.9 percent) had hip T-scores in the osteopenic range. We found that the patients with BMD in the osteoporotic and osteopenic ranges had no significant difference in the dietary calcium intake.
Conclusion The dietary calcium intake of our elderly patients with hip fractures is insufficient. They would benefit from dietary education and calcium supplements to prevent deterioration in bone density and subsequent osteoporotic fractures.

Keywords: calcium intake, dietary calcium, hip fractures, osteoporosis
Singapore Med J 2007; 48(12): 1117–1121

Ko GTC, Tang JSF
Correspondence: Dr Gary TC Ko, gtc_ko@yahoo.com.hk

ABSTRACT
Introduction With recognition of the important role of central obesity in metabolic syndrome (MES), the International Diabetes Federation (IDF) has proposed a revised definition for MES in early 2005. Information of MES in Chinese by IDF criteria is limited.
Methods This was a cross-sectional observation survey. A sample of 7,473 subjects (2,660 men and 4,813 women) was examined. They presented voluntarily in the period between August 2001 and September 2002 for health assessment at the three health centres of the United Christian Nethersole Community Health Service.
Results The mean age and standard deviation was 50.4 +/- 10.6 years (range 19-93 years, median 48.0 years). Among them, 30 percent had central obesity, 34 percent had low high-density lipoprotein cholesterol, 20 percent had hypertriglyceridaemia, 47 percent had high blood pressure, and 23 percent had dysglycaemia. The age-standardised percentages of MES by National Cholesterol Education Programme and IDF criteria were 18.3 and 13.9 percent, respectively.
Conclusion MES is not uncommon among the Hong Kong Chinese community. Further studies on the management and prevention of MES are indicated.

Keywords: Hong Kong Chinese, International Diabetes Federation, metabolic syndrome, obesity, waist circumference
Singapore Med J 2007; 48(12): 1111–1116

Heng KWJ, Tham KY, How KY, Foo JS, Lau YH, Li AYK
Correspondence: Dr Kenneth WJ Heng, kenneth_heng@ttsh.com.sg

ABSTRACT
Introduction Most patients presenting to the emergency department (ED) with minor head injury (HI) can be discharged, provided a caregiver is present and careful discharge instructions are given. The study ED uses an advice leaflet with verbal reinforcement to patients and caregivers detailing post-discharge instructions and warning symptoms of worsening HI. We aim to evaluate local patients' and caregivers' compliance to discharge instructions and their ability to recall HI advice.
Methods A prospective study was conducted in an adult ED between April 10, 2006 and May 1, 2006. All patients with minor HI discharged from the ED or its 24-hour observation ward were included in the study. A telephone survey was conducted within 48 hours of discharge using a standardised questionnaire.
Results During the study period, 292 patients had HI, of which 182 were eligible for the study. 71 were uncontactable and one refused to participate, leaving 110 patients in the study. Patients' age ranged between 7 and 109 years (median 41 years). 100 confirmed receiving HI advice (57 percent received by patients, 26 percent caregivers, 16 percent both patients and caregivers). 29 percent of respondents reported non-compliance to discharge advice. Mean HI-symptom recall score was 1.9 (SD 1.6) (total 9 symptoms). 30 percent cited other symptoms not part of the HI advice, which they believed necessitated a return to the ED. Recall scores were not statistically different, regardless of mode of instruction (verbal or printed) or the recipient (patient, caregiver or both).
Conclusion Our study raises concerns about the reliability of discharge advice for minor HI patients.

Keywords: discharge advice, emergency department, minor head injury
Singapore Med J 2007; 48(12): 1107–1110

Fong CW, Bhalla V, Heng D, Chua AV, Chan ML, Chew SK
Correspondence: Mr Fong Chee Weng, fong_chee_weng@moh.gov.sg

ABSTRACT
Introduction Socioeconomic differences in health-related behaviours have been widely studied in the Western populations, but are seldom considered in Asian populations. We examined the effect of education attainment on health-related behaviours (physical activity, cigarette smoking and alcohol consumption) among non-institutionalised Singaporeans aged 18-69 years.
Methods We used data from the Singapore National Health Survey 2004. Information on physical activity, cigarette smoking, alcohol consumption and sociodemographic characteristics was collected from 4,084 adults. Age-adjusted prevalence of the three health-related behaviours by educational attainment was calculated by the direct method. Logistic regression models, adjusted for age, gender, ethnic group and employment status, were used to estimate the odds ratio and 95% confidence interval, in order to study the prevalence of health-related behaviours according to educational attainment.
Results The prevalence of physical inactivity, daily smoking and regular alcohol consumption was found to be consistently highest among men and women with the least education. Prevalence of physical inactivity and smoking was inversely related to educational attainment for both genders. However, no clear gradient was found between education and alcohol consumption for men and women.
Conclusion Less-educated Singaporeans were more likely to smoke daily, drink alcohol regularly or not to exercise regularly. Health promotion policies or programmes aimed at encouraging healthy lifestyles in the Singapore population should take into account the educational inequalities in these health-related behaviours.

Keywords: educational inequalities, health promotion policies, health-related behaviours, Singapore National Health Survey, socioeconomic differences, socio-economic status
Singapore Med J 2007; 48(12): 1091–1099

Sivaperumal R, Subash S, Subramanian P
Correspondence: Dr P Subramanian, annamalai_rhythm@yahoo.co.in

ABSTRACT
Introduction The aim of the present study was to demonstrate the effects of aspartate on the circadian patterns of lipid peroxidation products and antioxidants in aspartate-treated rats, in order to investigate the influences of aspartate and whether it could modulate these rhythms differently, since aspartate is an important excitatory neurotransmitter (present in retinohypothalamic tract and suprachiasmatic nuclei [SCN]) involved in the generation and regulation of circadian rhythmicity.
Methods Aspartate (50 mg/kg body weight) was administered orally for 60 days to Wistar rats, and 24-hour rhythms of thiobarbituric acid reactive substances (TBARS), reduced glutathione (GSH), superoxide dismutase (SOD) and catalase were studied under semi-natural (light/dark 12:12 hr) conditions.
Results Exogenous aspartate administration caused acrophase advances in TBARS rhythms, and delays in GSH, SOD and catalase rhythms; altered MESOR and decreased amplitude values were also seen in all of these rhythms.
Conclusion Our findings indicate that the orally-treated aspartate could reach the hypothalamus, and various brain centres possibly including SCN, and could modulate the circadian patterns of lipid peroxidation products and antioxidants.

Keywords: aspartate, circadian pattern, lipid peroxidation products, reduced glutathione, superoxide dismutase, thiobarbituric acid reactive substances
Singapore Med J 2007; 48(11): 1033–1038