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M L Boey

Publications and source records attributed to M L Boey.

At least 37 records · Page 2Linked to original sources

The genetics of systemic lupus erythematosus.

Systemic lupus erythematosus (SLE) is a disease characterised by diverse clinical manifestations and the presence of multiple autoantibodies. There are multiple aetiological factors involved in its pathogenesis. Genetic factors do play an important role and the major histocompatibility complex has been studied extensively and many human leukocyte antigen (HLA) associations have been reported. Twin and familial lupus studies confirm the importance of genetic factors in the development of SLE. Reported HLA associations range from that of HLA-DR3 in Caucasians to HLA-DR2 in Chinese, Japanese and American Blacks. These associations however may only represent linkage disequilibrium and not the actual susceptibility genes. Other non-major histocompatibility complex genes have also been reported to play important roles in the pathogenesis of lupus. The advent of molecular biological techniques has advanced the understanding of susceptibility genes in many diseases. The use of microsatellite genome scanning to study multiplex lupus families has yielded a wealth of information on clusters of susceptibility genes. The identification of these genes will be an important advance in the understanding of this complex disease.

Animals↗

The effects of ethnicity on disease patterns in 472 Orientals with systemic lupus erythematosus.

OBJECTIVE: To determine the effects of ethnicity on disease manifestations in Oriental patients with systemic lupus erythematosus (SLE) and to describe the risk of developing renal or central nervous system (CNS) involvement with time. METHODS: A retrospective study of 472 patients with SLE seen at the only Rheumatology Unit in Singapore. The effect of ethnicity on selected disease manifestations at diagnosis was assessed after adjusting for demographic variables using multiple logistic regression. The probability of developing selected disease manifestations with time was determined using the Kaplan-Meier product limit method. RESULTS: At diagnosis, Malays had a higher risk of renal or CNS involvement than Chinese (OR 2.26, 95% CI 1.21 to 4.21, and OR 3.07, 95% CI 1.01 to 9.34, respectively), and Indians a lower risk of malar rash and a higher risk of oral ulcers than Chinese (OR 0.30, 95% CI 0.13 to 0.68, and OR 2.90, 95% CI 1.45 to 7.34, respectively). The prevalence of renal or CNS involvement in the entire cohort increased with time, reaching 75.6% (95% CI 66.1% to 85.0%) and 16.7% (95% CI 11.7% to 21.6%), respectively, after 18 years of disease. CONCLUSION: Ethnicity influenced disease manifestations at diagnosis in this cohort of Oriental patients with SLE. Renal or CNS involvement developed in previously unaffected patients up to 18 years after diagnosis, highlighting the need for continued vigilance in patients with lupus.

Adolescent↗

One hundred and seventy cases of childhood-onset rheumatological disease in Singapore.

One hundred and seventy patients with rheumatological disease diagnosed before their 16th birthday and still on follow up were studied retrospectively. They were seen within the last 3 years at KK Women's and Children's Hospital, Tan Tock Seng Hospital, National Skin Centre or Singapore General Hospital. Of these, 89 were still less than 16 years old at the time of study. The majority had systemic lupus erythematosus (51.8%). Many were on long-term follow-up for persistent disease, including renal manifestations (47.7%), neurological manifestations (26.1%) and haemolytic anaemia (15.9%). Photosensitivity and malar rash were more common than in Western studies while arthritis was less common. Anti-phospholipid antibodies were found in children complicated by myocardial infarction, pulmonary hypertension, Raynaud's phenomenon, cerebral and gut lupus. Children with juvenile chronic arthritis comprised 28.8% and juvenile dermatomyositis 10%. The male predominance and lack of uveitis in children with pauciarticular JCA were striking. Rarer conditions included polyarteritis nodosa, scleroderma, rheumatic fever with arthritis, polychondritis and Behcet's disease. Many diseases may first present with a rheumatological complaint. This review of features of local children highlights similarities and differences with Western data. It also provides information for planning long-term care, multidisciplinary clinics, group physiotherapy sessions, educational programmes and support groups.

Adolescent↗

Possible protective role of HLA-B*2706 for ankylosing spondylitis.

HLA-B27 is strongly associated with ankylosing spondylitis (AS) but the role of the HLA molecule itself is still unclear. In this study on Singapore Chinese, we have subtyped 50 B27 positive AS patients and 45 B27 positive normals and found that the B*2706 allele has a significant negative association with disease (p = 0.047). Together with recent data indicating the existence of AS "protective" B27 alleles, our data shows that the HLA molecule itself plays a crucial role in disease development.

Alleles↗

Pulmonary haemorrhage in Oriental patients with systemic lupus erythematosus.

We reviewed the case records of 10 Oriental patients with systemic lupus erythematosus (SLE) who developed pulmonary haemorrhage (PH) between 1987 and 1996 to determine their clinical presentation and outcome. All the patients had clinical evidence of PH including a sudden onset of dyspnoea, tachycardia, fall in haemoglobin (at least 1.5 gm%) and bilateral diffuse alveolar infiltrates on chest radiographs. At the time of PH, nine patients had a disease duration of 2 years or less and all the patients had clinical and/or laboratory evidence of active lupus disease. Fever and lung crepitations were present in 90% of patients while haemoptysis and chest pain occurred in only three and two patients, respectively. All the patients were treated with high dose intravenous corticosteroids and in addition seven had a combination of pulse methylprednisolone and cyclophosphamide, and four had received plasmapheresis. Four patients died as a result of PH. One patient died of pneumonia three years after recovering from PH while the remaining five had no recurrence of PH after a median follow-up of 22 months. Our study suggests that PH in Oriental lupus patients often occurs early in the disease, rarely presents with haemoptysis and has a high mortality despite aggressive immunosuppressive therapy.

Adolescent↗

Association of HLA-DRB1*0405 with extraarticular manifestations and erosions in Singaporean Chinese with rheumatoid arthritis.

OBJECTIVE: To determine the association of disease related HLA-DRB1 locus with disease severity and extraarticular features in Singaporean Chinese patients with rheumatoid arthritis (RA). METHODS: 70 patients with RA and 80 controls were typed for HLA class II alleles by the polymerase chain reaction-sequence specific oligonucleotide probe method. RESULTS: 56 patients (80%) had erosive disease; 51 were seropositive (73%), and 16 had extraarticular features (23%). Patients with HLA-DRB1*0405 had significantly higher prevalence of extraarticular features (43 vs 10%; p = 0.001) and erosions (93 vs 71%; p = 0.022) compared to those without the allele. There was also a greater frequency of seropositivity and joint surgery, and a higher number of second line agents used by patients with HLA-DRB1*0405 in comparison to those without, although the difference was not statistically significant. CONCLUSION: HLA-DRB1*0405 is associated with the presence of extraarticular features and erosions in Singaporean Chinese patients with RA.

Adolescent↗

The safety of weekly low dose oral methotrexate in an Oriental population with rheumatoid arthritis.

A retrospective review of 50 oriental patients with rheumatoid arthritis treated with weekly oral methotrexate showed adverse events in 15 (30%) patients with 19 occurrences (38%) of leucopaenia (4%), pancytopaenia (2%), gastrointestinal symptoms (18%), hepatic transaminase elevation (6%), rash (2%) and infections (6%). The median duration of treatment with methotrexate was 11 months (range 1 to 105 months). Pancytopaenia occurred in 1 patient with renal failure. All adverse events resolved with cessation of therapy and on several occasions, despite continued therapy. Methotrexate was discontinued permanently in 2 and temporarily in 7 patients as a result of adverse events. No recurrence of adverse events was noted on restarting methotrexate therapy in patients with non life-threatening adverse events. No increase in adverse events was noted in 14 patients treated with a combination of methotrexate and anti-malarial therapy. We conclude that methotrexate was well tolerated by the Oriental patients with rheumatoid arthritis in our study and could be safely restarted in those patients with non life-threatening adverse events.

Administration, Oral↗

Systemic lupus erythematosus: initial manifestations and clinical features after 10 years of disease.

We studied the initial manifestations and late features in our lupus patients. The clinical data of patients fulfilling the American College of Rheumatology criteria for systemic lupus erythematosus (SLE) were entered prospectively for newly diagnosed patients and cumulatively for those with at least 10 years of disease duration. Ninety-seven Group A (newly diagnosed; 86 females and 11 males; mean age 31 years; 83 Chinese, 11 Malays, and 3 Indians) and 58 Group B (more than 10 years disease duration; 56 females and 2 males; mean age 41 years; 50 Chinese, 5 Malays, and 3 Indians) lupus patients were studied. The commonest clinical features in Group A were: haematological (73%), arthritis (57%), malar rash (43%), renal disorder (31%) and photosensitivity (30%). Group B patients had haematological (78%), malar rash (73%), arthritis (69%), renal disorder (59%) and photosensitivity (33%). Renal disorder was significantly increased over the years (P < 0.001). Hypertension was present in 18% (Group A) and 59% (Group B) (P < 0.00001), diabetes mellitus in 5% (Group A) and 10% (Group B) (P = ns), atherosclerosis in 2% (Group A) and 7% (Group B) (P = ns). Cataract formation was not present in Group A patients but was present in 10% of Group B patients. Renal disorders and morbidity factors like hypertension and cataracts increased significantly over the years. Optimum treatment of lupus patients should therefore include close attention to these factors.

Adolescent↗

Initial construct cross-cultural validation of the Short Form 36 for quality of life assessment of systemic lupus erythematosus patients in Singapore.

The objective of this study was to determine if the Short Form 36 (SF-36) Health Survey Questionnaire measures differences in quality of life between lupus patients and healthy controls in Singapore. A cross-sectional pilot study was conducted on consecutive English-speaking, female Chinese lupus patients seen at a Rheumatology unit. Healthy volunteers were recruited as controls during the same time period. All subjects completed the United Kingdom version of the SF-36. Lupus disease activity was assessed using the British Isles Lupus Assessment Group (BILAG) index and converted to a global score. Lupus-related damage was measured using the Systemic Lupus International Collaborating Clinics/American College of Rheumatology Damage Index (SLICC/ACRDI). The main outcomes measured were the mean SF-36 scale scores for lupus patients and healthy controls. Thirty-six lupus patients and 76 controls were included in the study. All subjects were English-speaking, Chinese female between 21 and 53 years of age. The mean age of patients and controls was 31.9 and 29.0 years respectively. Lupus patients had lower mean scale scores than controls for physical functioning (73.0 versus 89.7, P < 0.0027), bodily pain (71.0 versus 81.4, P < 0.027), physical role functioning (55.7 versus 89.5, P < 0.0001) and general health (47.4 versus 51.8, P < 0.05). Mean scale scores for vitality, social and emotional role function and mental health were similar in both groups. Ten patients had active disease (BILAG global scores of 3 to 14) and 13 patients had lupus-related damage (Damage Index scores of 1 to 7). These preliminary data suggest that the SF-36 Health Survey may be able to measure differences in quality of life between lupus patients and healthy controls in Singapore.

Adult↗

Patterns of psoriatic arthritis in Orientals.

OBJECTIVE: To determine the clinical features of psoriatic arthritis (PsA) in a multiethnic Oriental population and to study the effect of ethnicity on disease patterns. METHODS: A retrospective study of 80 patients with PsA seen at either a rheumatology or dermatology referral center. Patients and case records were reviewed and data abstracted according to a standard protocol. Eighty consecutive patients with psoriasis without PsA seen at the dermatology center were recruited as controls. RESULTS: Asymmetric polyarthritis developing in the 4th decade with an equal male to female ratio was the commonest pattern of arthritis among Chinese, Indians, and Malays. Clinically apparent lumbar spondylitis was significantly more common in Indians than Chinese (10/11 vs 11/20, respectively; p = 0.046), although the prevalence of lumbar spondylitis was similar in all ethnic groups. Eighty-nine percent of subjects required nonsteroidal antiinflammatory drugs and 51% required disease modifying antirheumatic drugs at some time for control of joint disease. PsA was significantly more common among Indians compared to the ethnic distribution of the Singapore population (p < 0.000001). Multiple logistic regression identified Indian ethnicity as a risk factor for the development of PsA (OR 2.39, 95% confidence interval 1.02 to 5.60). CONCLUSION: The commonest pattern of PsA in all ethnic groups was asymmetric polyarthritis. Ethnicity affected the development and presentation of PsA in our series: Indians with psoriasis had double the risk of developing PsA compared to Chinese with psoriasis, and lumbar spondylitis when present in Chinese subjects was asymptomatic in 45%, being detectable only on radiological examination.

Adult↗

Transverse myelopathy in SLE: clinical features and functional outcomes.

The objective of the study was to examine the clinical features of lupus patients who present with transverse myelopathy (TM) and ascertain functional outcomes when treated early with high dose corticosteroids and/or cyclophosphamide. Case records of nine patients who developed a total of 14 episodes of TM were retrospectively studied. All the patients were female and their ages ranged from 21 to 59 years. Nine episodes of paraparesis, three of tetraparesis, one of numbness and one of neurogenic bladder were reported early in the diagnosis of SLE (median of two years). Neurogenic bowel and bladder and presence of ANA and ds-DNA were invariable. Urodynamics assessment in six patients showed abnormal detrusor behavior in all. CT scans and myelograms were uninformative and CSF studies were normal. ESR and complement levels were insensitive as markers of disease activity. The treatment regimens included pulses of methylprednisolone and/or cyclophosphamide followed by prednisolone and high dose prednisolone from onset. The functional outcomes were uniformly good-with independent ambulation in all except three (who needed assistive devices) and improvement of motor scores. Acute hospital stays were short (range of three to 45 days) whilst only two were referred for inpatient rehabilitation. Bladder abnormalities persisted despite motor recovery and would require long-term review.

Adult↗

Polymorphism of the regulatory region of tumour necrosis factor alpha gene in patients with systemic lupus erythematosus.

A single-base change in the regulatory region of the tumour necrosis factor alpha (TNF-alpha) gene and the TNF2 allele said to be associated with Caucasian lupus patients has been reported. We studied this genetic polymorphism in 89 normal individuals and 67 Chinese lupus patients, 45% of whom has renal involvement. The allelic frequencies of TNF1 and TNF2 alleles in our male controls (n = 49) were 0.86 and 0.14 respectively, in the female controls (n = 40) they were 0.91 and 0.09 respectively, and as a combined group they were 0.88 and 0.12 respectively. The corresponding frequencies in our lupus patients were 0.81 and 0.19 respectively. Comparing the allelic frequencies of the combined control and patient group as well as only between the female control and female lupus patients, we did not find any association between the TNF2 allele and systemic lupus erythematosus in our cohort of Chinese patients. The TNF2 gene may be in linkage disequilibrium with the DR3 allele.

Adult↗

Systemic lupus erythematosus (SLE) presenting as acute pancreatitis--a case report.

Acute pancreatitis is an uncommon manifestation of systemic lupus erythematosus (SLE). In most reported cases, it occurs in the setting of SLE with multi-organ involvement. We report an unusual case of SLE in a Sri Lankan woman presenting with acute pancreatitis with the pancreas as the sole major organ affected. The diagnosis of acute pancreatitis was based on clinical features, serum and urinary amylase levels and computerised tomography. She responded well to high-dose corticosteroid. We also review the literature and discuss the prevalence, theories of pathogenesis and treatment of this condition.

Acute Disease↗

Absence of retroviral antibodies in the sera of patients with systemic lupus erythematosus.

Retroviruses have been postulated as environmental triggers in the aetiopathogenesis of systemic lupus erythematosus. Sera from 100 lupus patients were screened for the presence of antibodies against recombinant HIV-1 core and envelope, and HIV-2 envelope antigens by an enzyme immunoassay. This will detect antibodies resulting from direct HIV-1 or HIV-2 infections or those generated as a result of antigenic similarities by other human retroviruses. The sera were obtained from 11 male and 89 female lupus patients. Retroviral antibodies were not detected in the sera of these lupus patients, thus contradicting published findings that up to 30% of lupus patients have antibodies against the p24 gag protein of HIV-1.

Antibodies, Viral↗

"Great mimicry" in a patient with tetraparesis: a case report.

The patient is a 63-year-old Chinese man who presented with tetraparesis and urinary incontinence. The initial diagnosis was cord compression from cervical spondylosis. The patient relapsed 3 months after cervical laminectomy. The transverse myelitis picture, left optic atrophy and suggestive brainstem evoked potentials led to treatment of a presumptive demyelinating process. The presence of vitiligo, however, led to detection of high titers of antinuclear antibodies (ANA) and presence of anti-nonhistone antibodies. The patient was then diagnosed to have a lupus (SLE)-like disease, which has not fully evolved. He was prescribed pulsed cyclophosphamide and prednisolone with significant gains both neurologically and functionally up to 1 year of follow-up. This report highlights the befuddling impact the disease process have on the clinicians in terms of diagnosis, treatment, and prognosis. That it can occur in men in the seventh decade of life heightens the need for awareness in our approach to the myelopathic patient.

Cervical Vertebrae↗

Systemic lupus erythematosus in 61 Oriental males. A study of clinical and laboratory manifestations.

The clinical and laboratory features of 61 oriental male lupus patients were compared to those of 86 oriental female patients to determine whether gender differences occur. Arthritis was significantly less common in the males. Neuropsychiatric disorders were less frequent but the difference did not reach statistical significance. Renal disease was the commonest clinical manifestation and diffuse proliferative glomerulonephritis the dominant histological finding on renal biopsy in the males. The prevalences of leucopenia and antibodies to extractable nuclear antigens in particular anti-Ro (SSA) and anti-La(SSB), were lower in men. Arthritis and serositis were less common in our oriental males in contrast to the caucasian patients. These findings provide further evidence of differences between the genders in SLE and suggest racial factors may affect clinical presentation.

Adolescent↗