The aims of this study were to examine the clinical and laboratory features of Malaysian patients with systemic lupus erythematosus (SLE) and to identify any difference in disease expression between the different genders and among the three major ethnic groups of Malaysia. Retrospective analysis of all patients with SLE admitted to and followed-up at University Hospital Kuala Lumpur from 1974-90 was undertaken. Ethnic Chinese had the highest prevalence of SLE compared to other ethnic groups. There was a high incidence of renal disease, 74% of patient had significant proteinuria and half of these had associated nephrotic syndrome. Indian patients had significantly less incidence of skin manifestation compared to other racial groups. No difference in disease expression was detected between the ethnic Chinese and Indians and between the male and female patients. The overall 5 y and 10 y survival rates were 82% and 70% respectively. Indian patients had the poorest survival rates. Survival rates are similar among the Chinese and Malay patients. Our findings are in broad agreement with those previously reported.
A retrospective analysis of the case records of 494 systemic lupus erythematosus (SLE) patients under follow-up at University Hospital, Kuala Lumpur during 1976-1990 was performed. Overall mortality was 20.2% (100 patients). The causes of death were infection (30%), renal (15%), respiratory (14%), neurological (5%), cardiovascular (7%), other causes (2%) and unknown (27%). Active SLE was a contributing factor in 19% of the deaths. The patients who died had significantly more renal disease, neurological disease, serositis or thrombocytopenia by the end of the first year of disease compared to the survivors. As in other series, infection and active SLE remain important causes of death.
SLE is an autoimmune and polygenic disorder characterized by an accumulation and deposition of immune complexes. Several studies have indicated differential impact of FcgammaR polymorphism genotypes in different ethnic groups studied. The Fc receptor for IgG class IIA gene (FcgammaRIIA) occurs in two allelic forms. The allele FcgammaRIIA-H131 encodes a receptor with a histidine at the 131 amino acid position; the other allele FcgammaRIIA-R131 encodes an arginine. This polymorphism is believed to determine the affinity of the receptor for hIgG2 in immune complexes. FcgammaRIIA-H131 has a higher capacity for hIgG2 compared to FcgammaRIIA-R131 as measured by in vitro studies of insoluble immune complex clearance. We have investigated the polymorphism for FcgammaRIIA using a novel polymerase chain reaction-allele specific primer (PCR-ASP) method designed specifically to distinguish the two allelic forms. Our studies were based on 175 Chinese and 50 Malays SLE patients as well as 108 and 50 ethnically matched healthy controls for the respective groups. Analysis of the data (chi2 test with Yates correction factors and odds ratios) revealed that there were no significant differences between SLE patients and controls. We have not found evidence of a protective effect conferred by FcgammaRIIA-H131 in the ethnic groups studied.
We conducted a prospective longitudinal study to determine the nature and prevalence of cardiac abnormalities in systemic lupus erythematosus and to study their natural history and relationship with disease activity. Forty consecutive inpatients with systemic lupus erythematosus were studied during their admission and subsequently 6 to 12 months later. On each occasion a clinical cardiovascular examination was carried out, disease activity was scored using the "Lupus Activity Criteria Count" and a Doppler echocardiographic examination was carried out. 72.5% of patients had an abnormal echocardiogram in the first study while 51.7% were abnormal during the follow-up study. Valvar disease occurred in 37.5% of patients. The mitral valve was most commonly affected. Libman-Sacks endocarditis was rare (2.5%). Pericardial effusions were seen in 36.2% of echocardiograms. The majority (76.0%) of these were associated with hypoalbuminaemia. 80.0% of patients had active disease during the first examination and 41.4% at follow-up. There was no correlation between activity of disease and prevalence of cardiac abnormalities at either examination. We conclude that cardiac disease is common in systemic lupus erythematosus. Prevalence of cardiac abnormality did not correlate with disease activity.
The neutrophil antigen (NA)1 and 2 is coded by two recognized allelic forms of Fc gamma receptor IIIB (FcgammaRIIIB). FcgammaRIIIb is a low affinity receptor and preferentially removes immune complexes from the circulation. Systemic lupus erythematosus (SLE) is an autoimmune and polygenic disorder characterized by accumulation of autoimmune complexes. The majority of SLE patients in our medical center are of Chinese ethnicity, followed by Malay and Indian. Recently, studies have focussed on the Fc receptors in different ethnic groups and their relation to SLE. We chose to study the gene distribution of this receptor in the Chinese and Malays population in Malaysia. We designed a polymerase chain reaction allele specific primers (PCR-ASP) method to distinguish the two allelic forms. Genomic DNA was isolated from the peripheral blood of 183 Chinese and 55 Malays SLE patients as well as 100 Chinese and 50 Malays healthy controls. Genotyping of Chinese SLE patients revealed that the gene frequencies for FcgammaRIIIB-NA1 and FcgammaRIIIB-NA2 were 0.648 and 0.347, while in the ethnically matched healthy controls they were 0.68 and 0.32, respectively. One out of the 183 Chinese SLE patients was identified as a NA-null due to the absence of PCR product for both alleles. The FcgammaRIIIB-NA1 and FcgammaRIIIB-NA2 allele frequencies for both the Malays SLE and healthy controls were 0.62 and 0.38.
An association of idiopathic systemic lupus erythematosus (ISLE) with genetically determined N-acetylation polymorphism has been suspected from previous studies, mainly on Caucasian populations in which there is an approximate incidence of 50% of slow and rapid acetylators. The present study is of the incidence of ISLE and acetylator status in a mixed population of Malaysia. The results did not support an association between ISLE and acetylator status: the frequencies of slow acetylators in the ISLE patients who were Malaysian Chinese and Malay were 13 and 38% respectively. This did not differ significantly from the respective healthy groups (20 and 29%). The small number of Indians in the survey did not allow a valid comparison, but the figures did suggest a lack of association between ISLE and acetylator status.
We report a significantly increased prevalence of antiribosomal P protein antibodies in Malaysian Chinese patients (38%) with SLE compared to white Caucasian (13%) and Afro-Caribbean (20%) patients. The increased prevalence was not due to a generalized increase in autoantibody production because anti-dsDNA and anti-SSA antibodies were present in comparable frequencies in the three ethnic groups while anti-Sm and anti-SSB antibodies were rarely found in the Malaysian Chinese patients.