Linkage disequilibrium of HLA-DR3 and HLA-DR4 with HLA-B alleles in Mexican patients with rheumatoid arthritis

OBJECTIVE

We studied the gene frequencies of classes I, II and III antigens of the Major Histocompatibility Complex (MHC) in 32 Mexican mestizo patients with rheumatoid arthritis (RA) and compared them with those obtained from 110 of their first degree relatives and 100 Mexican mestizo controls. Furthermore, we analyzed the observed and expected frequencies of the haplotypes and calculated the delta values in the three groups.

METHODS

The class I and class II MHC antigens were determined by the microlymphocytotoxicity test; class III MHC antigens were obtained by high voltage agarose gel electrophoresis and immunofixation. The significance of differences among the three groups was tested by chi-square analysis; linkage disequilibrium among the different alleles in each haplotype was estimated by computing the delta values (observed vs expected frequencies).

RESULTS

Patients showed a significantly increased frequency of HLA-A1 (corrected p = 10(-5)), DR3 (corrected p = 0.04) and DQ2 (corrected p = 10(-4)) and a decreased frequency of A31 (corrected p = 0.003) as compared to the normal controls. First degree relatives compared to patients and controls showed a decreased frequency of HLA-DR4 (corrected p = 0.02 and 0.008 respectively); consequently, DQ3 was also diminished (corrected p = 10(-4)). Analysis of MHC haplotypes within families revealed in the patients seven MHC haplotypes with significant differences between the observed and expected frequencies (statistically significant delta values). These haplotypes were: [HLA-B8; DR3], [HLAB44; FC31], [HLA-B8; SC42], [HLA-DR4; SC31], [HLA-B35; SC32], [HLA-DR7; FC31] and [HLA-DR2; SC31]. On the other hand, the control haplotypes showed significant delta values in only one of these haplotypes ([HLA-DR4; SC31]), whereas first degree relatives showed none. Analysis of all the class I, II and III alleles, either alone or as part of specific haplotypes, showed two B-DR haplotypes with higher relative risks than their alleles alone. These haplotypes were: [B44; DR4] (RR = 6.0, p = 0.005), and [B8; DR3] (RR = 8.3, p = 0.010).

CONCLUSION

The results suggest that a specific combination of antigens in the same haplotype (for instance between HLA-B and HLA-DR) could contribute to increasing the genetic susceptibility to develop RA.

Clinical, histopathological, immunological and fibroblast studies in 30 patients with subcutaneous injections of modelants including silicone and mineral oils

OBJECTIVE

To study patients with side effects secondary to the injection of modelants.

METHODS

We studied their clinical, serological, histopathological, radiographic, immunoregulatory and fibroblast culture features by standard methods. We studied thirty patients, 24 women, mean age: 38.2 years. Patients had received either mineral oil, guayacol, silicone or a mixture of these substances; some had received unknown material(s).

RESULTS

The mean time between the injection and the onset of symptoms was six years (range: 0.1-24 years). All patients had sclerodermatous skin changes, subcutaneous nodules, edema and/or hyperpigmentation at the site(s) of injection(s); five individuals also had skin changes at sites remote from the injection. Thirteen patients had clinical features of an autoimmune disease. Eleven patients gave a history of arthralgias including four that had symmetrical non-erosive polyarthritis. Twenty of 28 patients (71%) had positive anti-nuclear antibodies. We found intracellular spontaneous production of IL-1 (interleukin-1) by patients' macrophages which was almost absent in normal cells (p < 0.001). Silica-stimulated monocytes from patients also secreted more IL-1 than those from normal subjects (p < 0.001) in autologous mixed lymphocyte reaction. Twelve patients had an early proliferative response. At day seven, a decreased proliferative response was seen in 12/19 patients (p < 0.001). Skin fibroblasts from 3/3 patients synthesized 3-to-5-fold more 3H-hyaluronic acid than normal control cells (p < 0.001).

CONCLUSIONS

This report confirms the association between the injection of modelants and the development of autoimmune disease (human adjuvant disease, HAD). Our results implicate IL-1 in the amplification of the disease process. The similarities between primary scleroderma and human adjuvant disease now include immunological and connective tissue data. The study of these patients may help to understand the etiopathogenesis of some autoimmune diseases.

Quality of life in rheumatoid arthritis: validation of a Spanish version of the Arthritis Impact Measurement Scales (Spanish-AIMS)

OBJECTIVE

To translate and validate The Arthritis Impact Measurement Scales (AIMS) to be used by Spanish speaking populations.

METHODS

We administered the questionnaire to 97 outpatients with rheumatoid arthritis (RA) during routine patient care, in most cases with a trained interviewer. Reliability was assessed in stable patients using test-retest at a one-month interval. Internal consistency was evaluated with the coefficient of reliability. Convergent and construct validation was tested using ARA functional class, disease severity, disease activity, patient global assessment, and pain scores. Responsiveness was evaluated with one-tailed Student's t test and percentage of change.

RESULTS

Test-retest reliability was statistically significant for all scales except Activities of Daily Living and Anxiety. The coefficient of reliability was > 0.7 for all scales. Convergent and construct validity was detected with the constructs employed (Pearson's r > 0.4). Four/nine scales detected improvement (p < 0.05) in those patients in whom clinical change was recorded.

CONCLUSION

The Spanish-AIMS retained the methodological properties of the original version and can be used as an outcome measure in Spanish speaking patients with RA.

Influence of the antiphospholipid syndrome in the survival of patients with systemic lupus erythematosus

OBJECTIVE

To determine prognostic factors for mortality in a cohort of 667 patients with systemic lupus erythematosus (SLE) including those variables associated with the presence of antiphospholipid antibodies (aPL) as well as antiphospholipid syndrome (APS) itself.

METHODS

Analysis of the cohort under a nested case control design by means of Cox proportional hazards regression with and without stepwise method.

RESULTS

During the 2039 person-years of followup, there were 49 deaths (cases). Thrombocytopenia, arterial occlusions, and hemolytic anemia were the aPL related manifestations that were associated with decreased survival in univariate analyses. The first 2 were also selected among risk factors for mortality in stepwise Cox multivariate analysis. The syndrome itself was also associated with increased mortality rates, independently of other variables.

CONCLUSION

APS is among the variables that confer decreased survival on patients with SLE. This decreased survival is due to some (e.g., thrombocytopenia or arterial occlusions), but not all, of the manifestations of APS.

Exposure of anionic phospholipids upon platelet activation permits binding of beta 2 glycoprotein I and through it that of IgG antiphospholipid antibodies. Studies in platelets from patients with antiphospholipid syndrome and normal subjects

Patients with antiphospholipid syndrome, whether primary or secondary to systemic lupus erythematosus, may have thrombocytopenia. Their antibodies to anionic phospholipids might bind to phospholipids on the platelet wall but anionic phospholipids are asymmetrically located in the inner leaflet. In addition, antibodies to anionic phospholipids may require beta 2 glycoprotein I (beta 2GPI) as a cofactor in order to bind to phospholipids. In turn, beta 2GPI has high affinity for anionic phospholipids. Loss of this asymmetry occurs upon platelet activation and could thus permit such antibody-beta 2GPI-platelet interaction. We studied this by flow cytometry using purified beta 2GPI-FITC labelled and similarly labelled affinity-purified polyclonal antibodies to cardiolipin or phosphatidylserine (aPL) obtained from sera of patients with primary antiphospholipid syndrome. Five percent of resting platelets were bound by aPL in the presence of beta 2GPI. Such binding increased when we activated platelets with various agonists, reaching 31% with the concurrent use of thrombin and the calcium ionophore A23187. Platelet activation resulted in the expression of GMP140 but this did not correlate with aPL binding. This probably reflects that the expression of GMP140, which depends on their secretion of alpha granules, has different agonist responses and occurs at different times than do microvesicle formation and expression of prothrombinase activity which coincide with the loss of phospholipid asymmetry on the platelet wall. When we studied the binding of purified beta 2GPI we also found that it binds preferentially to activated platelets and that it seems to be a prerequisite for the binding of aPL onto them. Our findings indicate that aPL from patients with antiphospholipid syndrome may bind to activated platelets through beta 2GPI.

Listeriosis in patients with connective tissue diseases

OBJECTIVE

Patients with connective tissue diseases (CTD) are prone to infections, either from the disease itself or secondary to treatment. The incidence of listeriosis in immunosuppressed patients is increasing. We therefore evaluated the frequency of listeriosis, an otherwise rarely reported infection in the rheumatologic literature, in patients with CTD.

METHODS

Retrospective analysis of listeria positive cultures in patients with CTD between 1982 and 1992 at a tertiary care center in Mexico City.

RESULTS

We identified 8 patients: 7 with systemic lupus erythematosus and one with dermatomyositis. At the time of the infection, 5 had active disease, 6 were receiving prednisone and/or other immunosuppressive drugs and 2 were receiving hemodialysis. L. monocytogenes was isolated from cerebrospinal fluid (5 patients), from blood (one patient) and from both sites (2 patients). Patients had bacteremia without a known focus of infection or meningitis as the 2 most common clinical forms of listeriosis. In spite of appropriate antibiotic therapy, 4 patients died.

CONCLUSION

As in other immunosuppressed individuals, listeriosis is an aggressive infection in patients with CTD. Although rare, listeriosis should be included in the differential diagnosis of meningitis in patients with CTD and appropriate aggressive therapy rapidly instituted. To determine its frequency in rheumatic patients, multicentric prospective studies are required.

Myositis in primary Sjögren's syndrome. Report of 3 cases

OBJECTIVE

To describe the findings and course of myositis in primary Sjögren's syndrome (SS).

METHODS

We studied myositis in SS when clinically indicated. Of 104 patients with SS, we identified 3 cases. In all, the diagnosis was made according to clinical data, biochemical, electromyographic and biopsy criteria. Other autoimmune diseases were excluded.

RESULTS

We found a prevalence of 3% of myositis secondary to SS. There were no significant associations between myositis and other clinical or laboratory variables.

CONCLUSION

Although rare, myositis must be considered a part of the spectrum of SS. In our experience, treatment with steroids and immunosuppressive drugs was successful.

Antiphospholipid antibodies in patients with idiopathic autoimmune haemolytic anemia

Isolated cases of anti-phospholipid antibody (aPL)-associated idiopathic autoimmune haemolytic anemia (IAHA) have been recently described. To assess the significances of this association, we studied by ELISA the presence of aPL in sera from 18 patients with IAHA and 14 patients with non-autoimmune haemolysis (NON-AH). Four IAHA cases and none of the NON-AH controls showed IgM anticardiolipin antibodies (aCL) that crossreacted extensively with zwitterionic as well as with other anionic phospholipids. IgG aCL were detected in 6 patients with IAHA and in 1 patient with NON-AH; there was little cross-reactivity with other phospholipids. Our results suggest that antiphospholipid antibodies are present in a substantial number of patients with IAHA. This humoral response does not seem to be secondary to the haemolysis proper. The potential pathogenic significance of this finding is discussed.

Cellular and humoral immune parameters in women with pathological hyperprolactinemia before and during treatment with bromocriptine

PROBLEM

Experimental and clinical evidence has suggested an immunostimulatory effect of prolactin and that bromocriptine, an inhibitor of prolactin release, counteracts the actions of prolactin on the immune system. The aim of this study was to determine the impact of elevated serum prolactin levels on the immune system in patients with pathological hyperprolactinemia.

METHOD

For this purpose, parameters of the cellular and humoral immune system were studied in six women with prolactinomas and one with idiopathic hyperprolactinemia. Studies were performed when serum prolactin concentrations were high as well as during different phases of the menstrual cycle when prolactin levels had been normalized through treatment with bromocriptine.

RESULTS

Hyperprolactinemic subjects, when compared with six age-matched normal women, had significantly higher percentages of total lymphocytes and CD2+ cells. Elevation of CD4+ cells was also observed although to a lesser extent. Bromocriptine-treated patients, when compared with normal women were characterized by increased numbers of total lymphocytes and CD4+ cells, decreased percentage of CD8+ cells, and increased concentrations of serum IgM. These last two findings were also significantly different when compared to those observed in hyperprolactinemia.

CONCLUSION

In this study we have described the changes on cellular and immune parameters in patients with hyperprolactinemia before and during bromocriptine therapy, which support the links of communications between the immune and endocrine systems in humans.

Peripheral blood lymphocyte subsets and serum immunoglobulins in Sheehan's syndrome and in normal women during the menstrual cycle

OBJECTIVE

There has been increasing evidence on the mechanisms underlying the interactions between the neuroendocrine and the immune systems, particularly in animal models with relatively few information in the human. In this study, we evaluate the cellular and humoral immunity in female patients with hypopituitarism and in normal women throughout the menstrual cycle in an attempt to determine the role of pituitary and gonadal hormones on the immune system.

DESIGN

Serum immunoglobulins, peripheral blood lymphocyte subsets, and serum hormones were measured in eight patients with postpartum pituitary necrosis (Sheehan's syndrome) and in six normal women along different phases of the menstrual cycle, taking advantage of the lack of pituitary function and the cyclic variations in serum hormones, respectively.

RESULTS

Patients with Sheehan's syndrome had higher T lymphocytes (CD2), including helper (CD4) and suppressor (CD8) cell subpopulations and B lymphocytes (CD19) when compared with normal menstruating women. An increase of serum IgA concentrations was also observed. Normal women showed little non-statistically different changes along the menstrual cycle in peripheral blood cell parameters and in serum immunoglobulin levels.

CONCLUSIONS

a) Hypopituitarism in humans, in contrast with the animal model, may associate with immune up-regulation at both cellular and humoral levels; and b) hormonal changes along the normal menstrual cycle probably do not influence in great extent the immune system.

Influence of disease duration, continued followup and further antiphospholipid testing on the frequency and classification category of antiphospholipid syndrome in a cohort of patients with systemic lupus erythematosus

In an earlier study of a cohort of 667 patients with systemic lupus erythematosus (SLE) followed for 7.5 months with mean antiphospholipid (aPL) testing 2.5 times, we found a 10% prevalence of definite antiphospholipid syndrome (APS) (2 clinical manifestations and high aPL levels). To determine if more followup and aPL testing increased such prevalence we restudied the cohort after a mean followup of 3.1 years and a mean aPL testing of 5.6 times and found a 15% prevalence of definite APS. Another 21% of patients with SLE had probable APS with either high titers of aPL but only one clinical manifestation or low titers with 2 clinical manifestations. The prevalence of high titer positivity of aPL (IgG and/or IgM isotype) reached 41%. One aPL related feature that increased significantly was livedo reticularis possibly from increased awareness. Factors that influenced significantly the mobility upwards in APS category were more pregnancies and further aPL testing. Conversely, immunosuppressive treatment decreased higher aPL levels. The large number of patients with long disease duration in our cohort showed that the maximum prevalence of definite APS is reached after 15-18 years and is 23%. This might be the highest prevalence of definite APS within SLE.

Protein S deficiency associated to anti-protein S antibodies in a patient with mixed connective-tissue disease and its reversal by danazol

We describe here a female patient with mixed connective tissue disease, secondary antiphospholipid syndrome, pulmonary hypertension and severe acquired, probably autoimmune, antibody-mediated type I coagulation protein S deficiency (total, free and C4bp-bound). No previous instance of anti-PS antibody-associated PS deficiency had been reported. The patient was treated initially with prednisone, but the protein S levels did not rise until danazol was added, and dropped again after its withdrawal.

Phospholipid specificity and requirement of beta 2-glycoprotein-I for reactivity of antibodies from patients with primary antiphospholipid syndrome

Some disease manifestations are associated with serum antiphospholipid antibodies (aPL) in patients with systemic lupus erythematosus (SLE) in what has been termed antiphospholipid syndrome (aPLS). There are patients with aPLS who do not have SLE or any other illness who have been grouped under the term primary antiphospholipid syndrome (PAPS). However, patients with diverse infections, notably syphilis, may have aPL but do not develop the associated clinical manifestations. This has been attributed, at least in part, to the immunochemical features of their aPL, including the requirement for beta 2-glycoprotein-I (beta 2GP-I) for binding of aPL to phospholipids, but these have not been studied in sera from patients with PAPS. By ELISA we studied 95 sera from 17 patients with PAPS and 100 sera from clinically normal individuals for IgG and IgM antibodies to the main anionic and zwitterionic phospholipids and their related compounds, phosphatidic acid (PA) and synthetic phosphorylcholine (PRC). beta 2GP-I was present, either in newborn calf serum (NBCS) or purified, to block wells and to dilute samples, or was substituted by 0.3% gelatin. Inhibition studies with phospholipid micelles were used to confirm reactivities with the corresponding phospholipids. All 17 patients had IgG and 11 had IgM antibodies to cardiolipin. Antibodies to anionic phospholipids were primarily IgG whereas those to zwitterionic phospholipids were mainly, and often exclusively, IgM. We found a statistically significant difference in the mean levels of antibodies to all anionic phospholipids except aPTS, and to the haptene PA (P < 0.001) between patients and controls. The difference between levels of IgM antibodies to zwitterionic phospholipids was statistically significant with sphingomyelin (P < 0.001) and the haptene (P < 0.001). Levels of most IgG and most IgM aPL correlated significantly among them. The pattern and titers of reactivity are variable between patients, but stable within each patient. Requirement of beta 2GP-I for this reactivity was not an all-or-nothing phenomenon in individual sera. In general, as in lupus sera, antibodies to anionic phospholipids require that this cofactor be present coating the ELISA plates, whereas those to zwitterionic phospholipids do not. It would appear that patients with PAPS have polyclonal mixtures of antibodies that react with various phospholipids and have different requirements for beta 2GP-I for such reactivity.

Clinical manifestations of the antiphospholipid syndrome

We studied a large cohort of patients with systemic lupus erythematosus (SLE) to determine which manifestations associate with the antiphospholipids (aPL) and to ascertain when 2 or more such manifestations coexist, the association with aPL is stronger and the titers tend to be higher. We have confirmed that when aPL occur within SLE, they may account for some disease manifestations. We also described a similar syndrome occurring in the absence of a primary condition which we termed primary antiphospholipid syndrome (APS). Thus, we were able to construct preliminary criteria for the classification of APS as it occurs in SLE. With appropriate additions and exclusions to rule out SLE, these criteria could be applied to the classification of primary APS.

Measurement of disease activity in systemic lupus erythematosus. Prospective validation of 3 clinical indices

Several clinical indices have been proposed to measure disease activity in patients with systemic lupus erythematosus. Only a few have been subjected to extensive analysis. We report a methodological comparison of reliability, validity, responsiveness, and feasibility of the Lupus Activity Criteria Count, the Systemic Lupus Erythematosus Disease Activity Index (SLEDAI), and our own simplified modification of the latter (MEX-SLEDAI). They were applied prospectively to 39 patients with diverse degrees of disease activity in 3 consecutive visits. Inter-observer reliability outweighed experts' evaluation (rs = 0.86 to 0.89, p < 0.0001 versus 0.74). Significant association was demonstrated between indices and experts' judgment, managing physician's opinion, changes in treatment and clinical course. Moreover, indices showed good convergent validity (rs = 0.76 to 0.79, p < 0.0001), and responsiveness. MEX-SLEDAI was the least expensive instrument.

Raynaud's phenomenon in primary Sjögren's syndrome. Association with other extraglandular manifestations

One hundred and four patients with primary Sjögren's syndrome (SS) were evaluated for the presence (29%) or absence of Raynaud's phenomenon (RP). The clinical course of RP was, in general, benign and caused no vascular sequelae. In patients with primary SS having RP, nonerosive arthritis, vasculitis and pulmonary fibrosis were significantly more frequent than in those without RP. Myositis also appeared more frequently associated with RP, but the difference reached statistical significance only when combined in meta-analysis with 2 other comparable series. There were no differences in the autoantibody profiles of the 2 groups.

Course of antiphospholipid antibodies in patients with primary antiphospholipid syndrome before, during and after pregnancy treated with low dose aspirin. Relationship of antibody levels to outcome in 7 patients

We studied 7 patients with primary antiphospholipid syndrome (APS), who had had, between them, 28 fetal losses in 30 pregnancies. The 2 successful pregnancies had occurred 14 years previously. The patients had been followed for a mean of 20.5 months with a mean of 6.4 determinations of antiphospholipid antibodies (aPL) before becoming pregnant again. Serial determinations of aPL continued to be done throughout pregnancy. Patients were treated with low dose aspirin only except for one who had prednisone added at the time of an impending abortion. Five patients had successful outcomes and 2 had stillbirths. In the patients who had pregnancy loss, as well as in those who had other obstetric incidents there were abrupt changes in IgG, but not in IgM, levels. Levels of IgG aPL in patients with successful outcomes tended either to decrease gradually or to remain stable throughout. We conclude that patients with primary APS who had repeatedly unsuccessful pregnancies may show changes in their IgG levels during pregnancy that could indicate impending morbidity. In some of them low dose aspirin may prevent pregnancy loss.

Hyperprolactinemia inhibits natural killer (NK) cell function in vivo and its bromocriptine treatment not only corrects it but makes it more efficient

We studied NK cell function in eight patients with pathological hyperprolactinemia by measuring 51Cr release by K562 cells exposed to their mononuclear cells and found it decreased compared to normal controls (P less than 0.01). Bromocriptine (BrC) treatment corrected NK function but also made it more efficient at 12:1 than at 25:1 or 50:1 effector:target ratios (ANOVA; P = 0.01). The study of NK cell function in agarose revealed that its decrease in hyperprolactinemia is due to their low active binding to target cells, active killing, and recycling capacity. BrC tended to correct them but also increased recycling capacity to levels higher than those of controls (P less than 0.05). Sequential studies in three hyperprolactinemic patients before and after BrC showed correction of NK function within 1 week but its increased efficiency at the 12:1 effector:target ratio required 8 weeks. We conclude that hyperprolactinemia decreases NK cell function. BrC corrects this by decreasing prolactin levels but also makes NK function more efficient by increasing the capacity of NK cells to recycle after killing.