Various previous studies have reported the implication of CYP11B2 gene polymorphism in the pathophysiology of cardiovascular diseases. In particular, the -344T/C polymorphism, which is located at a putative binding site for the steroidogenic transcription factor (SF-1) has been associated with essential hypertension, left ventricular dilation and coronary heart disease. In the present study, we aim to determine the allele and genotype frequencies of the CYP11B2 gene in patients with clinical manifestation of coronary heart disease and confirmed by angiography and blood donors and to calculate the association of the gene polymorphism with CHD. A total of 79 DNA from patients with coronary heart disease admitted to the National Heart Institute and 84 healthy blood donors have been genotyped using polymerase chain reaction technique followed by restriction enzyme digestion (RFLP). Results of the study demonstrated that out of 79 for the patients, 40 were homozygous T, 10 were homozygous C and 29 were heterozygous TC. The frequencies of genotype TT, CC and TC for patients were 0.5, 0.13 and 0.36 respectively. The frequencies of allele T and C in patients were 0.68 and 0.31 respectively. While for the blood donors, 40 subjects were of homozygous T, 7 were homozygous C and 37 were heterozygous TC. The genotype frequencies for the TT, CC and TC were 0.47, 0.08 and 0.44 respectively. The frequency of the allele T was 0.69 and allele C was 0.3. Chi-Square analysis showed that there was no significant difference in the genotype and C allele frequencies between the CHD patients and the blood donors. Our study suggests that there is lack of association between -344T/C polymorphism of CYP11B2 gene and coronary heart disease.
Three monoclonal antibodies (McAb) were produced against soluble antigens of Legionella pneumophila serogroup 1 which was cultured on BCYE agar. The McAbs were all of the IgM isotype. The McAbs were used in the McAb-based ELISA for detection of circulating L. pneumophila antigens in 186 sera collected from patients with symptoms and signs suggestive of atypical pneumonia. The normal reference optical (OD) density value of each of the McAbs was determined using 44 sera collected from healthy blood donors. The antigen positivity rates for the McAbs 1C7.2B, 2B2.10F and 2B2.11E were 11.3%, 7.7% and 22.2% respectively. Antigen positivity of the McAb 2B2.10F was significantly higher in the younger age group (p < 0.05). There is no significant association between the antigen positivity with age and sex for all the McAbs. There was no cross-reaction demonstrated between the McAbs with other bacterial antigens.
We studied the prevalence of antinuclear (ANA), anti-double stranded DNA (dsDNA), anti-Sm and anti-RNP antibodies in a group of 93 blood donors (age range: 18-58 years). Antinuclear and anti-ds DNA antibodies were detected by immunofluorescence (IF) using HEp2 cells and Crithidia luciliae as substrates, respectively, while anti-Sm and anti-RNP antibodies were assayed by ELISA. ANA was found in 6.5% while anti-dsDNA antibodies were not detected in any of the subjects. The 98th percentile was used as cut off where values greater than 0.651 for anti-Sm and 0.601 for anti-RNP antibodies were taken to be positive. This gives a frequency of 1.1% for both antibodies. There was no significant association of antibody positivity with sex or race. We conclude that certain autoantibodies are present in low titres in the normal Malaysian Individuals, at a different frequency compared to other studies probably due to genetic, ethic or environmental factors.
A study of 101 sera from 69 Malay, 14 Chinese and 18 Indian healthy adult Malaysians was undertaken to determine the frequency of antinuclear antibodies (ANA), antimitochondrial antibodies (AMA), antismooth muscle antibodies (SMA) and antiparietal cell antibodies (APCA). There were 67 females and 34 males with a mean age of 31.7 years (+/-8.6). ANA was assayed by immunofluorescence (IF) using both mouse liver and HEp-2 cell substrates. AMA, SMA and APCA were also tested by IF using composite sections from mouse liver, kidney and stomach substrates. Analysis showed 6.9% were positive for ANA at a titre of 1:40 with HEp-2 while only 1.9% were detected using mouse liver. 9.9% had detectable AMA from titres 1:10 to 1:90. None of them had detectable SMA and only 1 (0.09%) had APCA at a titre of 1:80. This study suggests that a diagnosis of an autoimmune disorder has to be cautiously made taking into consideration that autoantibodies are present in low titres in the healthy population.
Autoantibodies have been known to be detected during pregnancy. The occurrence of autoantibodies during pregnancy was studied in a group of 146 healthy pregnant women from Jan-March 1995. Serum samples were tested for antinuclear (ANA), anti-ds DNA, anti-mitochondrial, anti-smooth muscle and anti-parietal cell antibodies employing the technique of indirect immunofluorescence. Sera from 66 non-pregnant women were used as controls. Among the pregnant group, 2 (1.4%) were found to have ANA positivity in comparison to none in the control group. This difference was found to be not statistically significant. Only 1 (0.7%) was positive for anti-mitochondrial antibody in the pregnant group compared to one in the control group (p > 0.05). However, anti-ds DNA, anti-smooth muscle and anti-parietal cell antibodies were not detected in both groups. All those positive for autoantibodies were in their 2nd trimester. When these cases were followed-up at the end of their pregnancy, none had complicated pregnancies nor infant abnormalities. Our findings suggest that (a) the occurrence of autoantibodies in pregnant women was not significantly different from non-pregnant controls and that (b) maternal autoantibodies did not appear to cause complications during pregnancy or infant morbidity.
The etiology of systemic lupus erythematosus (SLE) is unknown but genetic factors seem to play a role in the disease pathogenesis. The tumor necrosis factor alpha (TNFa) gene, encoded at the TNF locus in the MHC class III region, is now known to be an important candidate gene in SLE, due to the proinflammatory activities of the TNFa. The objectives of this study were to examine the role of the TNFa polymorphism for the susceptibility of Malaysian Chinese lupus patients to SLE and to determine its association with organ involvement. The allelic frequencies of the TNFa polymorphic variant (TNF2) of seventy lupus patients were determined during follow-up at the Medical Clinic of the National University Hospital Malaysia by PCR-RFLP technique. Sixty-four females and 6 males with a mean age of 33+/-12 years were included. Clinical data were obtained from case records. Autoantibody levels were measured by ELISA. Fifty-nine ethnically-matched blood donors were used as controls. The allelic frequency of the TNF2 variant was found to be significantly increased in the patients compared to the controls (52.8% vs 33.8%). SLE patients with the polymorphic TNF2 variant were found to be at increased risk of central nervous system involvement (p = 0.004, RR = 2.59) and to have an increased frequency of anti-La antibodies (p = 0.03). In view of these findings we suggest that TNF2 variant is playing a role in conferring susceptibility to SLE and in the disease pathogenesis.
Study site: Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Leptospirosis is an emerging infectious disease. The differential diagnosis of leptospirosis is difficult due to the varied and often "flu like" symptoms which may result in a missed or delayed diagnosis. Leptospira is the aetiological agent of leptospirosis, a bacterial zoonosis with worldwide distribution. There are over 230 known serovars in the genus Leptospira. The true prevalence of leptospirosis in Malaysia is unknown or underestimated. Our goal was to determine the prevalence for Leptospira infection in rodents in a selected area in Beguk Dam Labis, Segamat, Johor. A study was carried out on 69 serum samples of trapped wild rodents. DNA was extracted from the sera using Leptospira PCR kit (Shanghai ZJ Bio-Tech Co., Ltd). Of 69 rodent serum samples tested by PCR, 9 (13%) showed positive results. In this study we found that (13%) of wild rodents caught in Beguk Dam Labis were infected by Leptospira.
The frequency of the HLA class II antigens/alleles (HLA-DR, DQ and DP) were studied in 70 Malaysian Chinese patients with systemic lupus erythematosus (SLE) to examine the contribution of these genes to disease susceptibility, their clinical expression and Immunological responses. This was done using modified PCR-RFLP technique. These samples were then compared with 66 ethnically matched controls. We found a strong association of the DQA1*0102 (p corr = 0.032, rr = 3.39), DQB1*0501 (p corr = 0.003, rr = 4.55), *0601 (p corr = 0.006, rr = 4.22) and DPB1* 0901(p corr = 0.02, rr = 4.58) with SLE. Clinically, we found a strong association of DR2 and DQA1*0301 with renal involvement and DQA1*0102 with alopecia. Immunologically, statistical analysis (Chi-square test ) showed a strong association of DQA1*0102 with anti-Ro/La antibodies while DQA1*0301 was observed to be strongly associated with antibodies to ds DNA. DQA1*0102 was found more frequently in those with a later disease onset (30 years of age or above). From these data we suggest that the HLA class II genes play a role in conferring disease susceptibility and clinical and immunological expression.
Study site: SLE clinics, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
An analysis of the clinical and serological features of 12 male and 122 female patients with SLE was done to determine whether sex related differences exist. We found a lower incidence of mucocutaneous symptoms and arthritis but an increased incidence of discoid lesions, pleuritis and pericarditis in males at disease onset. During the disease course, there was a lower incidence of arthritis, a similar prevalence of mucocutaneous symptoms but an increased incidence of pleuritis in males with a trend towards renal involvement. These findings were however not statistically significant except for the higher incidence of thrombosis among males. Serologically, both groups showed similar frequencies of autoantibodies and hypocomplementaemia. Although the study was small, it was shown that several sex-related differences in the clinical and serological features exist in Malaysian SLE patients.
Study site: SLE Clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Thirty-six patients with lupus nephritis (LN) attending the Nephrology Clinic, Hospital Kuala Lumpur were studied for the prevalence of anticardiolipin antibody (ACA) isotypes (IgG and IgM) and other associated antibodies, antinuclear antibody (ANA) and anti-ds DNA antibody and to determine the possible association between serological and clinical parameters. The study population consisted of 20 (55.6%) Malays, 15 (41.7%) Chinese and 1 (2.8%) Indian with a mean age of 31.4 +/- 11.3 years, range 14 to 60 years. The female to male ratio was 11:1. The average time between diagnosis and blood sampling was 4.4 years (range 0.25 to 15 years). Increased ACA levels were found in 20 (55.6%) patients where raised IgG ACA and IgM ACA were observed in 20 (55.6%) and 2 (5.6%) cases respectively. ANA and anti-ds DNA antibodies were detected in 22 (61.1%) and 4 (11.1%) individuals respectively, with the majority (82%) showing a speckled pattern of nuclear staining. However, neither the IgM ACA nor IgG ACA showed any significant association with thrombosis or any other clinical parametres. Our preliminary study indicates that ACA is a frequent finding in lupus nephritis and that the IgG isotype is more prevalent.
Study site: nephrology Clinic, Hospital Kuala Lumpu
BACKGROUND: Studies have shown that certain genes within the major histocompatibility complex predispose to systemic lupus erythematosus (SLE) and may influence clinical and autoantibody expression. Thus, we studied the frequency of HLA-DR, -DQA, -DQB and -DPB alleles in ethnic Malays with SLE to determine the role of these genes in determining disease susceptibility and their association with clinical and immunological manifestations.
METHODS: Fifty-six Malay SLE patients were enrolled into the study. Demographic, clinical and immunological findings were obtained from medical records. HLA-DR, DQ and DP typing were done using modified PCR-RELP. Controls were from ethnically-matched healthy individuals.
RESULTS: We found a strongly significant association of the DR2 and DQB1 *0501 and DQB1*0601 (pcorr = 0.03, rr = 3.83, pcorr = 0.0036, rr = 4.56 and pcorr = 0.0048 and rr = 6.0, respectively). There was also a weak increase of DQB1*0.201 and DPB1*0.0901 with a weak decrease of DQA1*0601 and DQB1*0503 and *0301 which were not significant after corrections for multiple comparisons were made. There was a significant positive association of DR2 and DQB1*0501 with renal involvement and DR8 with alopecia. A nonsignificant increase of DQB1*0503 in patients with photosensitivity was noted. Significant autoantibody associations were also found: DQB1*0601 with anti-Sm/RNP, DR2 with antiSSA (Ro)/SSB (La), and DR2, DQB1*0501 and *0601 with antibodies to ds DNA. There was no specific DR, DQ or DP associations with age of disease onset (below 30 years or those at or above 30 years).
CONCLUSION: Our data suggests the role of the HLA class II genes in conferring SLE susceptibility and in clinical and autoantibody expression.
Study site: SLE Clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Health care workers have been reported to constitute one of the few high-risk groups related to IgE-mediated hypersensitivity associated with the use of latex products. This paper describes the first ever study of prevalence carried out in Malaysia among these workers. One hundred and thirty health care personnel from Hospital Kuala Lumpur were skin tested. Extracts used were prepared from seven different brands of natural rubber latex gloves with varying levels of extractable protein (EPRRIM). Out of the 130 volunteers, 4 (3.1%) had positive skin test to latex with extracts with high levels of EPRRIM (> 0.7 mg/g). The prevalence among the Malaysian health care workers can be considered to be low in comparison to that of some consumer countries as the USA which reported a prevalence of as high as 16.9%.