Is incident rheumatoid arthritis interstitial lung disease associated with methotrexate treatment? Results from a multivariate analysis in the ERAS and ERAN inception cohorts.

OBJECTIVES: To assess predictive factors for rheumatoid arthritis interstitial lung disease (RA-ILD) in two early rheumatoid arthritis (RA) inception cohorts with a focus on methotrexate (MTX) exposure. DESIGN: Multicentre prospective early RA inception cohort studies; the early RA study (ERAS) and the early RA network (ERAN). SETTING: Secondary care, ERAS nine centres, ERAN 23 centres in England, Wales and Ireland. PARTICIPANTS: Patients with new diagnosis of RA, n=2701. Standardised data including demographics, drug therapies and clinical outcomes including the presence of RA-ILD were collected at baseline, within 3-6 months, at 12 months and annually thereafter. PRIMARY AND SECONDARY OUTCOME MEASURES: Primary outcome was the association of MTX exposure on RA-ILD diagnosis. Secondary outcomes were the association of demographic, comorbid and RA-specific factors on RA-ILD diagnosis and the association of MTX exposure on time to RA-ILD diagnosis. RESULTS: Of 92 eligible ILD cases, 39 occurred in 1578 (2.5%) MTX exposed and 53 in 1114 (4.8%) non-MTX exposed cases. The primary analysis of RA-ILD cases only developing after any conventional synthetic disease-modifying antirheumatic drug treatment (n=67) showed MTX exposure not to be associated with incident RA-ILD (OR 0.85, 95% CI 0.49 to 1.49, p=0.578) and a non-significant trend for delayed ILD diagnosis (OR 0.54, 95% CI 0.28 to 1.06, p=0.072). In an extended analysis including RA-ILD cases present at RA diagnosis (n=92), MTX exposure was associated with a significantly reduced risk of incident RA-ILD (OR 0.48, 95% CI 0.3 to 0.79, p=0.004) and longer time to ILD diagnosis (OR 0.41, 95% CI 0.23 to 0.75, p=0.004). Other independent baseline associations with incident RA-ILD were higher age of RA onset, ever smoking, male gender, rheumatoid nodules and longer time from first RA symptom to first outpatient visit. CONCLUSIONS: MTX treatment was not associated with an increased risk of RA-ILD diagnosis. On the contrary, evidence suggested that MTX may delay the onset of ILD.

The influence of nonsteroidal anti-inflammatory drugs and probenecid on the renal response to and kinetics of piretanide in man.

The mechanism by which nonsteroidal antiinflammatory drugs interfere with the action of loop diuretics is not clear. We studied the renal response to an acute challenge of piretanide superimposed on pretreatment with either placebo, probenecid, indomethacin, or piroxicam in seven maximally hydrated subjects. No change was seen in glomerular filtration rate, as measured by creatinine clearance, throughout the experiments. When compared with responses to piretanide challenge after placebo pretreatment, probenecid reduced by 65% the peak fractional excretion of sodium (FENa), with a corresponding reduction in diuretic excretion. Pretreatment with indomethacin reduced peak FENa by 35%, but urinary delivery of piretanide was not altered. In contrast, piroxicam did not influence FENa but significantly reduced the delivery of both sodium and piretanide into urine. We conclude that the activity of nonsteroidal antiinflammatory drugs within the renal tubule varies among individual drugs and cannot be explained solely by their common mechanism of antiinflammatory action.

SLE nephritis: an ultrastructural immunogold study to evaluate the relationship between immune complexes and the basement membrane components type IV collagen, fibronectin and heparan sulphate proteoglycans.

The nature of immune complexes and their relationship to the normal glomerular basement membrane (GBM) components type IV collagen, fibronectin, and heparan sulphate proteoglycans (HSPG) have been examined in the glomeruli of 7 cases of systemic lupus erythematosus (SLE) glomerulonephritis using an ultrastructural immunogold technique. In paraformaldehyde-fixed, Lowicryl resin-embedded tissue, the electron-dense deposits contained IgG, IgM, IgA, and C3 whether they were subepithelial, intramembranous, subendothelial, or mesangial and there was no particular relationship between the class of immunoglobulin and site of immune complex localization within the glomerulus. The normal GBM components type IV collagen, fibronectin, and HSPG were found within all the glomeruli, but did not have the same distribution. Type IV collagen and fibronectin were found predominantly on the inner aspect of the GBM and diffusely throughout the more central regions of the mesangial matrix. By contrast the HSPG was seen mainly on the outer aspect of the GBM and at the periphery of the mesangial matrix. In none of the cases were GBM antigens localized within the electron-dense deposits, results which suggest that autoantibodies to these GBM components may not play a role in the development of the glomerulonephritis.

Production of soluble recombinant proteins with Kell, Duffy and Lutheran blood group antigen activity, and their use in screening human sera for Kell, Duffy and Lutheran antibodies.

The aim of this study was to show that soluble recombinant (sr) proteins can mimic blood group antigens and be used to screen human sera for blood-group-specific antibodies. The blood of all pregnant women and pretransfusion patients should be screened for blood-group-specific antibodies to identify and monitor pregnancies at risk of haemolytic disease of the foetus and newborn (HDFN), and to prevent haemolytic transfusion reactions. Current antibody screening and identification methods use human red blood cell panels, which can complicate antibody identification if more than one antibody specificity is present. COS-7 cells were transfected to produce sr forms of the extracellular domains of the red blood cell membrane proteins that express Kell, Duffy or Lutheran blood group antigens. These sr proteins were used to screen for and identify anti-Kell, anti-Duffy or anti-Lutheran blood-group-specific allo-antibodies in human sera by haemagglutination inhibition and in solid-phase enzyme-linked immunosorbent assays (ELISAs). There is a positive correlation (correlation coefficient 0.605, P value 0.002) between antibody titre by standard indirect antiglobulin test (IAT) and signal intensity in the ELISA test. This work shows that sr proteins can mimic blood group antigens and react with human allogeneic antibodies, and that such proteins could be used to develop solid-phase, high-throughput blood group antibody screening and identification platforms.

Mortality in rheumatoid arthritis. Increased in the early course of disease, in ischaemic heart disease and in pulmonary fibrosis.

OBJECTIVE: To examine the cause of death in a large UK inception cohort of rheumatoid arthritis (RA), and whether this was related to disease duration and severity, treatment effects or extra-articular features and complications of RA. METHODS: Standard clinical, laboratory, radiological and socio-economic measures were recorded at baseline and yearly in an inception cohort started in nine centres in 1986. Date and the cause of death were based on death certificates and the comparisons made with age and sex matched population figures. Risk factors for mortality were identified from baseline measures of disease. RESULTS: There were 459 deaths (32%) in 1429 patients followed for up to 18 yrs. Standard mortality ratio was 1.27. Survival was significantly lower in the first 7 yrs of RA. Excess mortality was seen in cardiovascular disease (31%), pulmonary fibrosis (4%) and lymphoma (2.3%). Baseline predictors for mortality were men, older age, poor function, lower socio-economic status, extra-articular features, comorbidity, rheumatoid factor, X-ray erosions, high-ESR and low-haemoglobin. CONCLUSION: There was a modest increase in mortality in RA, mainly in the first 7 yrs. Deaths from cardiovascular disease and pulmonary fibrosis were higher than expected, but treatment-related deaths were low. Risk factors included less favourable socio-economic status, markers of disease severity and diminished function within the first year.

Association of DRB1 shared epitope genotypes with early mortality in rheumatoid arthritis: results of eighteen years of followup from the early rheumatoid arthritis study.

OBJECTIVE: To determine whether the HLA-DRB1 shared epitope (SE) is associated with early mortality and specific causes of death in rheumatoid arthritis (RA). METHODS: HLA-DRB1 genotyping was carried out on blood samples from 767 patients recruited for the Early RA Study (ERAS), a multicenter, inception cohort study with followup over 18 years. Dates and causes of death (n = 186) were obtained from the Office of National Statistics. The association of HLA-DRB1 alleles with risk of mortality was assessed using Cox proportional hazards regression analyses. Multivariate stepwise models were used to assess the predictive value of HLA-DRB1 genotypes compared with other potential baseline risk factors. RESULTS: The SE was not significantly associated with overall mortality. However, the presence of 2 SE alleles was associated with risk of mortality from ischemic heart disease (hazard ratio [HR] 2.02 [95% confidence interval 1.04-3.94], P = 0.04), and malignancy (HR 2.18 [95% confidence interval 1.17-4.08], P = 0.01). Analysis of specific SE genotypes (corrected for age and sex) revealed that the HLA-DRB1*0101/*0401 and 0404/*0404 genotypes were the strongest predictors of mortality from ischemic heart disease (HR 5.11 and HR 7.55, respectively), and DRB1*0101/*0401 showed a possible interaction with smoking. Male sex, erythrocyte sedimentation rate, and Carstairs Deprivation Index were also predictive, but the Health Assessment Questionnaire score, rheumatoid factor, nodules, and swollen joint counts were not. Mortality due to malignancy was particularly associated with DRB1*0101 genotypes. CONCLUSION: The risk of mortality due to ischemic heart disease or cancer in RA is increased in patients carrying HLA-DRB1 genotypes with particular homozygous and compound heterozygous SE combinations.

Class II antigens on dendritic cells from the synovial fluids of patients with inflammatory arthritis.

Dendritic cells were enriched from synovial fluids (SF) of patients with inflammatory arthritis and studied by immunogold labelling and electron microscopy for expression of histocompatability antigens of the HLA-D locus. Dendritic cells from SF were larger than most of these from peripheral blood with a more extensive Golgi region and more lysosomes and microfilaments. Class II histocompatability antigens HLA-DR, -DP, -DQ and that labelled by the antibody RFDI were abundant on the dendritic cells. The macrophages in the enriched cells showed labelling for DR but little labelling with the other antibodies. DR, DP and RFDI were often concentrated at areas of contact between dendritic and other cells (other dendritic cells, macrophages or lymphocytes). On incubating labelled cells at 37 degrees C for 30 min many macrophages lost their DR label but dendritic cells always retained some surface label. Some gold labelling DR and DP was found in characteristic channels between the veils and became internalized in membrane-bound structures. A small proportion of the RFDI label internalized in areas resembling coated pits. Less DQ label internalized and appeared on vesicles inside vacuoles. Material bound to different class II molecules may thus be internalized or processed differently by dendritic cells. The presence in inflammatory lesions of large activated dendritic cells with high expression of class II antigens suggests that these cells could be presenting antigen to lymphocytes within the joints.

Effect of maximal hydration on the renal responses to pretreatment with nonsteroidal anti-inflammatory drugs and probenecid in man.

The renal response to a challenge of maximal water diuresis has been studied in seven subjects pretreated over 48 h with either placebo, probenecid, indomethacin or piroxicam. Probenecid did not alter the excretion of water and sodium chloride when compared with placebo responses, but increased both phosphate and urate clearances. Indomethacin reduced significantly both water and sodium chloride clearances by approximately 40%. Piroxicam reduced water excretion to a similar extent but did not influence salt output. In parallel with these changes, both drugs caused significant phosphaturia. It is concluded that the renal actions of nonsteroidal anti-inflammatory drugs (NSAIDs) are individually distinct and involve direct effects on tubular transport of ions and water to differing extents within both the proximal and distal portions of the nephron.

The effects of naproxen and sulindac on renal function and their interaction with hydrochlorothiazide and piretanide in man.

We have studied the effect of a single dose challenge of naproxen (500 mg) and sulindac (200 mg) on renal function in five volunteers, and the effect of a single dose challenge of the thiazide, hydrochlorothiazide (100 mg), and loop diuretic, piretanide (6 mg) on renal function when the diuretics were given alone or when superimposed on chronic therapy of either naproxen or sulindac. None of the nonsteroidal anti-inflammatory drug (NSAID) or diuretic exposures significantly influenced glomerular filtration rate, as measured by creatinine clearance. Over the first 4 h of the study, both naproxen and sulindac reduced fractional excretion of sodium by approximately 50%. Sulindac also caused a significant uricosuria whilst naproxen promoted urate retention. Similar changes were observed over 8 h. Superimposition of either hydrochlorothiazide or piretanide on top of chronic sulindac therapy resulted in a blunting of the natriuresis by approximately 30% compared to when these diuretics were given alone: the action of the diuretics was unchanged by naproxen. Sulindac pretreatment did not alter the urinary excretion of either hydrochlorothiazide or piretanide; naproxen did not alter hydrochlorothiazide excretion. On the basis of these findings, it is concluded that NSAIDs exert direct tubular effects that do not necessarily interfere with the delivery of diuretics to their sites of action within the nephron.

Renal responses and pharmacokinetics of piretanide in humans: effect of route of administration, state of hydration and probenecid pretreatment.

The influence of route of administration, state of hydration and transport inhibitor probenecid on the renal responses of a loop diuretic, piretanide, were investigated in 14 healthy volunteers. Maximally achieved plasma concentrations after i.v. and oral piretanide were higher in the nonhydrated state [+54% (i.v.); + 68% (oral)], accompanied by significant decreases in mean residence time, renal clearance and fraction of unchanged drug excreted with nonsignificant decreases in t1/2, steady-state volume of distribution and total clearance when compared with the hydrated state. Relative differences between the two hydrated states in maximal plasma concentrations of piretanide remained after probenecid [+26% (i.v.); +55% (oral)] but changes in kinetic parameters did not. Pretreatment with probenecid produced significant increases in absolute peak and plasma diuretic concentrations, t1/2 and mean residence time while decreasing steady-state volume of distribution, total clearance, renal clearance and fraction of unchanged drug excreted without affecting the bioavailability of piretanide. Urinary drug recovery was greater after i.v. than after oral piretanide, the recovery being consistently lower in nonhydrated state [iv: 2.78 (nonhydrated) versus 3.41 mg/24 h (hydrated); oral: 1.93 (nonhydrated) versus 2.76 mg/24 h (hydrated)]. Probenecid pretreatment reduced the overall urinary recovery of piretanide without altering the i.v./oral differences. Excretion of sodium paralleled piretanide excretion throughout the study except after i.v. dosing in the nonhydrated state where changes in drug excretion after probenecid (2.55 versus 1.63 mg/6 h) failed to influence sodium output (167 versus 152 mmol/6 h). These results demonstrate the importance of route of administration and state of hydration in determining the pharmacocological response of loop diuretics within the kidney.

Familial chondrocalcinosis due to calcium pyrophosphate dihydrate crystal deposition in English families.

Familial predisposition to chondrocalcinosis (CC) due to calcium pyrophosphate dihydrate (CPPD) crystal deposition is described in five English kindreds. Two families were characterized by premature-onset polyarticular CC with little associated structural arthropathy. In one of these families, recurrent childhood fits were strongly associated with subsequent development of CC. Affected members of the other three families resembled sporadic disease in showing predominantly late-onset, oligoarticular CC with mild arthritis and destructive change in only one case. Knee synovial fluid levels of inorganic pyrophosphate (PPi) and nucleoside triphosphate pyrophosphate (NTPP) did not differ from those of 59 sporadic cases of CC due to CPPD, although PPi and NTPP levels in both groups were higher than in normal knee synovial fluid (P less than 0.0001). Urinary PPi levels were not different from normal controls. Screening for other metabolic abnormality was negative in all cases. This is the first report of familial CC in the UK, and the first to associate this condition with childhood fits. Absence of overt primary abnormality of PPi metabolism suggests that other factors relating to crystal nucleation/growth may be more relevant to predisposition in these cases.

VCAM-1 expression on endothelium in lesions from cutaneous lupus erythematosus is increased compared with systemic and localized scleroderma.

The cutaneous lesions in systemic sclerosis (SSc) and lupus erythematosus (LE) are pathologically distinct and may display separate cell adhesion receptors. We have scored lesional skin for the presence of cell adhesion molecules that may influence inflammatory and fibrotic processes in five patients with LE, six patients with diffuse scleroderma and four patients with morphoea. The immunohistological distribution, and the number and intensity of cells staining, were recorded for VCAM-1, ICAM-1, E-selectin, alpha 2 to alpha 6 and beta 2 integrins and HLA-DR. VCAM-1 staining intensity was increased on endothelium from lesions in LE compared with SSc (P = 0.05). Low-level VCAM-1 and E-selectin expression was present on endothelium from uninvolved skin including that from patients with morphoea. HLA-DR expression was increased on infiltrating mononuclear cells (P < 0.05) and keratinocytes in LE (P < 0.05) and the number of fibroblasts staining for ICAM-1 was increased in lesions from patients with SSc, although this did not reach statistical significance. Overall, with respect to endothelial adhesion events, our findings support an important role for VCAM-1 in sustaining chronic inflammation in cutaneous LE.

Localisation of a gene for chondrocalcinosis to chromosome 5p.

Chondrocalcinosis is a common disorder which may associate with acute and chronic arthritis. A familial form, inherited as an autosomal dominant trait, has been mapped in a large family in which affected members also suffer recurrent fits in childhood. The gene which causes this disease shows linkage with several polymorphic markers on chromosome 5p with a maximum multipoint lod score of 4.6 between D5S810 and D5S416. Mapping a locus for chondrocalcinosis will allow the heterogeneity of the disorder to be assessed and may also be relevant to understanding the aetiology of osteoarthritis with which it commonly associates.

Characterisation of anticytoplasmic antibodies and their clinical associations.

OBJECTIVES: To characterise the cytoplasmic staining patterns identified by indirect immunofluorescence (IF) of human epithelial (HEp-2) cells and the antigens recognised using additional serological techniques. To define the disease associations of anticytoplasmic antibodies. METHODS: Sera from 1173 patients were screened for cytoplasmic IF staining on HEp-2 cells and the patterns characterised. The presence of antimitochondrial antibodies (AMA) was evaluated by a sensitive anti-pyruvate dehydrogenase complex enzyme linked immunosorbent assay (ELISA) (IgG) and by immunoblotting. Detection of antibodies to extractable nuclear antigens (ENA) was performed by double immunodiffusion and the presence of anti-ribosomal P antibodies was determined by immunoblotting. RESULTS: Cytoplasmic IF staining was demonstrated in 75 sera (6.4%). Six different patterns were recognised: coarse granular filamentous speckles (AMA, n = 9); condensed large speckles (anti-golgi apparatus antibodies, n = 3); cytoskeletal (n = 9); centriolar (n = 4); diffuse coarse speckles (n = 33); and fine speckles (n = 17). Of the nine sera with an AMA pattern, the presence of these antibodies was confirmed in seven by the ELISA (n = 6) and on immunoblotting (n = 7). One of the seven patients had primary biliary cirrhosis, and two had scleroderma. Two patients with anti-golgi antibodies had rheumatoid arthritis and two with anticentriolar antibodies had scleroderma. Of 33 sera that had cytoplasmic staining and were ANA negative, three were positive for anti-Ro and two were positive for anti-Jo-1 antibodies. CONCLUSIONS: In general, defined cytoplasmic IF patterns have no specific disease associations. However, the finding of cytoplasmic fluorescence should not be ignored, as it may indicate the presence of antibodies to ENA in the absence of nuclear staining.

Impaired glucocorticoid induction of mononuclear leukocyte lipocortin-1 in rheumatoid arthritis.

OBJECTIVE: To investigate leukocyte lipocortin-1 production in rheumatoid arthritis (RA). METHODS: Eight control and 8 RA subjects received 100 mg hydrocortisone intravenously. Leukocyte lipocortin-1 was measured by enzyme-linked immunosorbent assay. RESULTS: Hydrocortisone induced significant increases in lipocortin-1 production by control mononuclear cells (MNC) (P = 0.006 versus baseline) but not by RA MNC (P = 0.44 versus baseline). Peak lipocortin-1 levels in control MNC were significantly higher than those in RA MNC (P = 0.014). CONCLUSION: These results indicate that glucocorticoid-induced MNC lipocortin-1 production is impaired in RA.

Expression of the cutaneous lymphocyte antigen and its counter-receptor E-selectin in the skin and joints of patients with psoriatic arthritis.

We have investigated whether the skin-homing T lymphocytes identified by the cutaneous lymphocyte antigen (CLA) are increased in the synovial membrane of patients with psoriatic arthritis. Twenty-six synovial samples (13 psoriatic arthritis, seven rheumatoid arthritis, six osteoarthritis) were obtained from involved knees. Lesional skin biopsies were taken from nine of the patients with psoriatic arthritis and six patients with psoriasis alone. All samples were single- and dual-stained for CLA and CD3 (to identify T lymphocytes) using HECA-452 (anti-CLA) and anti-CD3 monoclonal antibodies. E-selectin expression was also determined. The percentage of dual-stained lymphocytes was significantly greater in psoriatic skin than in synovium (P < 0.001) and similar between psoriatic and rheumatoid synovium. There was no significant difference in the percentages of CLA-positive cells in psoriatic skin in patients with psoriatic arthritis compared with psoriasis alone. The intensity of endothelial E-selectin expression was significantly greater in skin psoriasis than in synovium (P < 2 x 10(-5)), and rheumatoid synovium had significantly greater expression than psoriatic synovium (P < 0.05). However, there was no significant correlation between E-selectin expression and the percentages of CLA-positive lymphocytes. This study provides further evidence that the CLA antigen is enriched on skin-homing lymphocytes. Conversely, the link between skin and joint inflammation in psoriatic arthritis does not seem to be explained by increased trafficking of CLA T cells to psoriatic synovium.

Orthopaedic intervention in early rheumatoid arthritis. Occurrence and predictive factors in an inception cohort of 1064 patients followed for 5 years.

OBJECTIVES: To assess the occurrence of and predictive factors for orthopaedic surgery in an inception cohort of rheumatoid arthritis (RA) patients recruited and followed prospectively for 5 yr in nine regions in England. METHODS: Standard clinical, laboratory and radiological assessments and all interventions were recorded at baseline and yearly in RA patients (less than 2 yrs symptoms) prior to the use of disease-modifying drugs. RESULTS: One thousand and sixty-four patients completed 5 yr of follow-up. Two hundred and sixty-four orthopaedic procedures for RA were performed in 181 (17%) patients at a median of 36.5 months from baseline. Seventy-five (7%) had replacements of major joints. Risk factors at baseline for large joint replacement surgery were a low haemoglobin concentration [odds ratio scores (OR) 3.4, 95% confidence interval (CI) 2.1-5.8] and high scores for erythrocyte sedimentation rate (ESR) (OR 3.2, CI 1.8-5.3), disease activity (DAS) (OR 2.1, CI 1.2-3.5) and Larsen X-rays (OR 2.6, CI 1.4-4.8). For hand or foot joint surgery (4%), risk factors included female gender (OR 3.2, CI 1.3-7.6), joint score (OR 2.3, CI 1.2-4.3), erosions (OR 2.3, CI 1.1-4.8), DAS (OR 2.4, 1.3-4.5) and Health Assessment Questionnaire score (OR 1.9, CI 1.0-3.6). No significant associations were seen for tendon, soft tissue or other minor procedures (6%). The HLA-DRB1 RA shared epitope was associated with any type of orthopaedic surgery (OR 1.7, CI 1.1-2.7). CONCLUSIONS: Eleven per cent of RA patients treated with conventional drug therapy for 5 yr underwent large- or small-joint surgery, an outcome which could be compared against that for new disease-modifying drugs. Risk factors varied according to type of surgery, but included standard clinical and laboratory measures. In order to reduce the eventual need for surgery, a therapeutic target in the first year of RA is the suppression of disease activity, as measured by haemoglobin and ESR. These are useful details for clinicians, health professionals and patients.

Differential expression of the costimulatory molecules B7.1 (CD80) and B7.2 (CD86) in rheumatoid synovial tissue.

CD4+ T-lymphocytes require two signals to become activated--antigen receptor (TcR) occupancy and an antigen-presenting cell (APC)-derived costimulus. The latter may be provided by B7.1 (CD80) or B7.2 (CD86) on APC interacting with CD28 on T-cells. We have studied the expression of these costimulatory molecules in rheumatoid and osteoarthritic synovial membrane. Very few B7.1-positive cells were seen in synovial tissue from either established or early rheumatoid disease, or in rheumatoid arthritis (RA) or osteoarthritis (OA) synovia at arthroplasty. In contrast, B7.2 was readily detected in rheumatoid synovia, predominantly in the lining layer, in a pattern of expression that corresponded to the presence of CD68-positive macrophages. Only occasional B7.2-positive cells were seen in OA synovia. The presence of B7.2 but the relative lack of expression of B7.1 may be partly responsible for the observations of 'frustrated' T-cell activation or T-cell hyporesponsiveness in the rheumatoid synovium.