Nuntana Kasitanon

Sensitivity and specificity of ANA and anti-dsDNA in the diagnosis of systemic lupus erythematosus: a comparison using control sera obtained from healthy individuals and patients with multiple medical problems.

BACKGROUND Antinuclear antibodies (ANA) and anti-double stranded DNA (anti-dsDNA) are often tested as a screening tool in patients with suspected systemic lupus erythematosus or connective tissue diseases. ANA can be seen in healthy controls (HC) and patients with multiple medical problems (MMP). OBJECTIVE To determine the sensitivity and specificity of ANA and anti-dsDNA in SLE patients, using sera from HC and MMP patients. METHODS Serum samples from HC, MMP and SLE patients, 100 in each group, were analyzed for the presence of ANA and anti-dsDNA, by indirect immunofluorescent assay, using a HEp-2 cell and Crithidia luciliae as substrates, respectively. RESULTS The prevalence of ANA at a titer of ≥1:80 and ≥ 1:160 was 8% and 4%, respectively, in HC; and it was 12% and 6% respectively, in MMP patients. The prevalence of anti-dsDNA was 0% in HC and 3% in MMP patients. When using HC sera for the diagnosis of SLE, the sensitivity of ANA at a titer of ≥ 1:80 and ≥ 1:160 was 98% and 90%, respectively, with specificity of 92% and 96%, respectively. The specificity decreased to 88% and 94%, respectively, when using sera from MMP patients. The specificity of anti-dsDNA was 100% and 97%, when using sera from HC and MMP patients, respectively. CONCLUSION ANA and anti-dsDNA gave high sensitivity and high specificity in patients with SLE, even when using MMP patients sera as controls. Physicians should take care in interpreting ANA and anti-dsDNA results in MMP patients who do not have signs or symptoms of SLE or connective tissue diseases.

Usefulness of pleural effusion antinuclear antibodies in the diagnosis of lupus pleuritis

We performed this study to determine sensitivity and specificity of pleural effusion antinuclear antibodies (ANA) at a titer of ≥1 : 160, and the ratio of pleural effusion to serum ANA of ≥1, to distinguish between pleural fluid from lupus pleuritis and other causes. A prospective study of 54 patients with pleural effusion (12 lupus pleuritis, seven parapneumonic effusion, 26 malignancy-associated pleural effusions, nine transudative effusions) was performed. ANA at a titer of ≥1 : 160 were found in 11 of 12 lupus pleuritis samples, and in four of 42 pleural effusions from non-systemic lupus erythematosus (SLE) patients. The pleural effusion ANA at a titer of ≥1 : 160 gave a sensitivity of 91.67% for lupus pleuritis, with a specificity of 83.33% when compared with all other pleural effusions, 90.91% when compared with exudative effusion (parapneumonic effusion and malignancy-associated effusion) and 55.56% when compared with the transudative pleural effusion group. Using the ratio of pleural effusion to serum ANA of ≥1, the sensitivity and the specificity decreased to 75.00% and 78.57%, respectively. This study provides further evidence that the pleural effusion ANA at a titer of ≥1 : 160 is a sensitive and specific diagnostic biomarker for lupus pleuritis in patients with lupus. However, pleural effusion ANA can occasionally be found in other conditions.

Associated factors and psychotherapy on sleep disturbances in systemic lupus erythematosus

Sleep disturbance is a common problem in systemic lupus erythematosus (SLE) patients. This study was performed to determine the prevalence of sleep disturbance in SLE, the factors that might be associated with sleep disturbance, and the correlation between changes in clinical parameters and sleep quality over time. Fifty-six female SLE patients from a total of 497 SLE patients (11.3%) agreed to join the study. The demographic data were recorded at baseline and the clinical data, the Pittsburgh Sleep Quality Index (PSQI) and other standardized assessment tools, disease activity index, quality of life (QoL), damage index, depression, anxiety and fatigue score, were assessed three times: the first visit was at baseline, the second time was one month later, and the third time was three months after the baseline. Thirty-one of these 56 patients (55.36%) were found to have sleep disturbances. All were females with their mean ± SD age of 37.5 ± 12.3 years, and disease duration at study entry of 8.6 ± 7.3 years. There was no association between sleep disturbances and demographic data, disease activity, clinical symptoms, the presence of autoantibodies and current steroid use. In multiple logistic regression analyses, only moderate to severe depression was the independent determinant of sleep disturbances, p = 0.036. During the three-month observation, with the treatment, the changing of total PSQI score showed a significantly positive correlation with depression, anxiety, pain and QoL. Sleep disturbances in Thai SLE patients were not uncommon but a correctable condition. Depression was strongly associated with sleep disturbances. Awareness of underlying depression as well as sleep disturbances in SLE patients and treating them properly improve QoL in SLE.

Effect of minidose aspirin on renal function and renal uric acid handling in healthy young adults

Minidose aspirin (60–325 mg/day) has been widely used in the prevention and treatment of cardiovascular and cerebrovascular diseases. However, studies on the effects of minidose aspirin on renal handling of uric acid and renal function are limited. We studied the effect of aspirin at 60 mg/day (n = 18) and 300 mg/day (n = 14) on uric acid handling and renal function in healthy subjects. The subjects were evaluated weekly during 2 weeks of aspirin therapy, and again 1 week after aspirin was discontinued. Aspirin at both dosages decreased the fractional excretion of uric acid. However, aspirin at 300 mg/day, but not 60 mg/day, significantly decreased uric acid clearance and creatinine clearance by the end of the second week of aspirin therapy. Despite these changes, serum uric acid and serum creatinine remained constant. The uric acid clearance, but not the creatinine clearance, returned to baseline value 1 week after aspirin therapy was discontinued. As aspirin at 60 mg/day showed no suppressive effect on renal function, it may be better for long-term use.

High-resolution computed tomographic findings in systemic sclerosis-associated interstitial lung disease: comparison between diffuse and limited systemic sclerosis.

ObjectiveThis study aimed to compare the high-resolution computed tomographic (HRCT) findings between patients with diffuse cutaneous systemic sclerosis (DcSSc) and limited cutaneous systemic sclerosis (LcSSc) as well as to correlate the HRCT scores and the other variables. MethodsThe medical records of all patients with SSc who presented at the Rheumatology Clinic, Chiang Mai University Hospital, from March 2005 to 2010 and underwent HRCT of the chest for the presence of interstitial lung disease were retrospectively reviewed. The extent of ground glass, lung fibrosis, and honeycombing was scored. All scores were aggregated to produce a total CT perfusion score. The widest coronal esophageal diameter (WED), the maximum diameter of the main pulmonary artery (MPAD), and ascending aortic diameter (AD) were measured. The ratio of MPAD to AD (MPAD/AD) was calculated. ResultsOf the 71 patients with SSc, mean (SD) age and disease duration were 54.8 (11.8) and 3.9 (4.2) years, respectively. Of them, 69.0% were female and 67.6% were classified as having DcSSc. There were no significant differences between patients with DcSSc and LcSSc with respect to age, disease duration, New York Heart Association Functional Classification, the calculated HRCT scores, WED, and MPAD. The lung fibrosis and total CT perfusion score correlated inversely with the SpO2 (r = −0.47, P < 0.01). The honeycombing correlated positively with the New York Heart Association Functional Classification and the WED (r = 0.29 and r = 0.32, respectively, P < 0.05). ConclusionsThe HRCT scores of these patients were comparable in both subtypes of SSc. Careful evaluation of lungs and esophageal involvement should be performed irrespective of SSc subtypes. The calculated HRCT scores may be useful to assess the severity of the interstitial lung disease in SSc.

Lack of CTGF*-945C/G Dimorphism in Thai Patients with Systemic Sclerosis.

An association between connective tissue growth factor (CTGF) gene dimorphism at –945 (CTGF*-945C/G) and systemic sclerosis (SSc) has been reported with inconclusive results. We performed this study to determine whether such an association exists among Thai patients with SSc. DNA samples were taken from 50 Thai SSc patients (diffuse SSc in 39 and limited SSc in 11) and 99 healthy controls for determination of CTGF*-945C/G dimorphism by polymerase chain reaction (PCR) using specific oligonucleotide primers. The associations between the genotype frequencies, clinical manifestations and auto-antibodies were determined as well. When compared with the controls, SSc patients had no significantly higher frequencies of the GG genotype (44.0% vs 39.4%, p = 0.60), G allele (63.0% vs 65.2%, p = 0.80) or G phenotype (82.0% vs 90.9%, p = 1.0). There was no association between the presence of the GG genotype and clinical manifestations (pulmonary fibrosis, sclerodactyly, digital pitting scars, telangiectasia and pulmonary arterial hypertension), or the presence of auto-antibodies (anti-Scl-70, anti-SSA/Ro, and anti-RNP). In conclusion, we found no association between CTGF*-945C/G dimorphism and Thai SSc patients.

Periodontal disease in Thai patients with rheumatoid arthritis

To evaluate the prevalence and severity of periodontal disease in patients with rheumatoid arthritis (RA) who attended a rheumatology clinic in a university hospital.

Comparison of proteinuria determination by urine dipstick, spot urine protein creatinine index, and urine protein 24 hours in lupus patients.

Background:A simple, convenient, and accurate method for detecting urine protein excretion in lupus nephritis is crucial. Objectives:The objectives of the study were to determine the sensitivity and the specificity of the qualitative urine dipstick test value to detect 0.50 g or greater of the quantitative 24-hour urine protein (24-hUP) in lupus patients, to evaluate an overall agreement of the dipstick test results and the magnitude of 24-hUP, and to examine the correlation between the spot urine protein creatinine index (S-UPCI) and the 24-hour UPCI with that of the 24-hUP. Methods:A prospective study was conducted in 92 patients with lupus. All dipstick test values from 5 dipstick assays (Bayer, Roche, Meditest USA, Standard Diagnostics, and Arkray) and the S-UPCI were obtained within 6 hours of the 24-hUP collection. Of 149 urine samples, only 39% were collected properly and were used for analysis. Results:The sensitivity and specificity of a ≥2+ dipstick test result to detect 0.50 g or greater 24-hUP were 56-% to 80% and 67% to 92%, respectively. The agreement of the urine dipstick test values and the magnitude of 24-hUP was fair (&kgr; = 0.23-0.32). The correlation between the S-UPCI and the 24-hUP was 0.83 (P < 0.0001), and that of the 24-hour UPCI and the 24-hUP was 1 (P < 0.0001). Using 24-hUP 2 g/d or less, the bias ±1.96 SD of the difference of S-UPCI and 24-hUP was 0.23 (SD, 0.96) g. Conclusions:A ≥2+ dipstick test is relatively sensitive to detect significant proteinuria, but it is poorly correlated with quantitative 24-hUP. The S-UPCI and the 24-hUP can be used interchangeably for follow-up in lupus nephritis patients with proteinuria of less than 2 g/d.

Comprehensibility, reliability, validity, and responsiveness of the Thai version of the Health Assessment Questionnaire in Thai patients with rheumatoid arthritis

IntroductionThe Health Assessment Questionnaire Disability Index (HAQ-DI) is a commonly used instrument to assess functional status of patients with rheumatoid arthritis (RA). Translations and adaptations of the HAQ-DI have been carried out for use with RA patients in several countries. The objective of this study was to evaluate the psychometric properties of the Thai version of the HAQ-DI (Thai HAQ) in Thai patients with RA.MethodsComprehensibility of the Thai HAQ was assessed by 126 patients with RA from 6 medical centers in Thailand. Another group of 115 patients with active RA was enrolled to test the reliability (internal reliability and 1-week test-retest reliability), construct validity (correlations with other measures of RA disease activity), floor and ceiling effects, and sensitivity to change of the Thai HAQ at 3 months of treatment with disease-modifying antirheumatic drugs.ResultsMore than 98% of the patients regarded the Thai HAQ as comprehensible. The internal consistency of the Thai HAQ was satisfactory with the overall Cronbach alpha of 0.91. The test-retest reliability of the Thai HAQ was acceptable with the intraclass correlation coefficient of 0.89. Moderate correlations between the Thai HAQ and other outcomes of RA disease activity were observed, except erythrocyte sedimentation rate, with the Spearman correlation coefficients ranging from 0.42 to 0.57. The responsiveness of the Thai HAQ was moderate, with a standardized response mean of 0.75 (95% confidence interval 0.56 to 0.94).ConclusionsThe Thai HAQ is comprehensible, reliable, valid and sensitive to change in the evaluation of functional status of Thai patients with RA. The Thai HAQ is an essential tool to measure treatment effects and progression of disability in RA patients and should be applied in both clinical trials and routine clinical care settings.

An evaluation of the association of leukopenia and severe infection in patients with systemic lupus erythematosus.

BackgroundLeukopenia is a common finding in systemic lupus erythematosus (SLE) and may contribute to severe infections. ObjectivesThe objectives of this study were to determine the prevalence of leukopenia in SLE patients and examine the association between these conditions and severe infections noting the risk factor of severe infections. MethodsThis study was a prospective inception lupus cohort of newly diagnosed SLE patients seen between May 2007 and June 2011. Only cases that had been observed for a minimum of 1 year or died during the study were included. ResultsThere were 89 SLE patients (92% females), with their mean (SD) age and disease duration at the study entry of 31.7 (12.2) years and 2.4 (2.9) months. Leukopenia was found at the diagnosis in 51.6% of the cases. The cumulative prevalence of leukopenia, lymphopenia, and neutropenia was observed in 57.3%, 96.6%, and 60.7%, respectively. Persistent lymphopenia, noted continuously for more than or equal to 75% of the observation period, was found in 41.6%, but there was no persistent neutropenia. The incidence rate of severe infection was 12.4 per 100 patient-years. There was no difference of severe infection–free survival rate between patients who ever and never had leukopenia. In the multivariate analysis, using cyclophosphamide was the independent predictor for severe infection in SLE (hazard ratio, 2.73; 95% confidence interval, 1.10–6.77). ConclusionsLeukopenia was common in SLE but usually not persistent. In this study, the presence of leukopenia at any time was not the risk factor for severe infection in SLE. Cyclophosphamide was the important predictor for severe infection in SLE.