The latex fixation test in rheumatic diseases: a review

Periodontal infection as a possible severity factor for rheumatoid arthritis

OBJECTIVE

Clinical effects of periodontal treatment on biochemical and clinical markers of disease severity in rheumatoid arthritis (RA) patients with periodontal disease were evaluated.

METHODS

Forty-two patients were assigned to two groups, G1 (n=16) and G2 (n=26). G1 patients were submitted to oral hygiene instruction and professional tooth cleaning and G2 patients additionally had full-mouth scaling and root planing (SRP). Clinical periodontal measurements were obtained at baseline and 3 months after periodontal treatment. A Health Assessment Questionnaire (HAQ) was used to evaluate their performance on daily living. Rheumatoid factor (RF), erythrocyte sedimentation rate (ESR) and drug therapy were assessed.

RESULTS

Both groups presented a full-mouth improvement in all periodontal clinical parameters (p<0.05), with the exception of clinical attachment level (CAL) and probing pocket depth (PPD) >6 mm for G1. G2 showed greater mean reductions on PPD >4 mm than G1 (p<0.001). HAQ analyses showed a reduction on the degree of disability of G2, but not statistically significant. ESR was significantly reduced for G2 after SRP although RF did not show statistical reductions.

CONCLUSION

The data suggest that periodontal treatment with SRP might have an effect on the ESR reduction.

Chronic tophaceous gouty arthritis mimicking rheumatoid arthritis

OBJECTIVES

To analyze the factors which differentiate chronic tophaceous arthritis from rheumatoid arthritis.

METHODS

We describe two cases of chronic gouty arthritis masquerading as rheumatoid arthritis. The characteristic features of each of these two conditions and the diagnostic approach are discussed in light of relevant literature.

RESULTS

The correct diagnosis was reached by the combination of accurate history taking (family history of gout, alcoholism, previous diuretic therapy and renal stones), guiding clinical features (subcutaneous tophaceous deposits) and specific radiological (assymetrical erosions with sclerotic margins and overlying edges) and laboratory findings (hyperuricemia and hyperuricosuria). It was confirmed by the identification of monosodium urate (MSU) crystals in the synovial and subcutaneous tissues.

CONCLUSIONS

Gout and rheumatoid arthritis rarely coexist. Chronic gouty arthritis may mimic rheumatoid arthritis, and vice-versa. Clinical suspicion supplemented by characteristic laboratory, radiological and histologic findings help at reaching an accurate diagnosis.

Rheumatoid factors in the sera of patient with gastrointestinal carcinoma

One hundred and nineteen patients with gastrointestinal (GI) malignancy (80 colorectal, 25 gastric and 14 pancreatic carcinoma) were studied for rheumatoid factors (RF), antinuclear antibodies (ANA) and immunoglobulin levels and the findings correlated with size of tumor, stage of disease and survival. Twenty three (19.3%) of the patients were RF seropositive compared to 5.7% of 70 matched controls (P = 0.02). In two thirds of the seropositive patients RF were detected prior to the initiation of treatment. The proportion of RF seropositivity increased significantly in patients with tumors larger than 4 cm and in patients with Stage D disease. The authors found a high incidence of ANA in the patients: 32.4% compared to 8% in normal subjects (P less than 0.01), but the proportion of RF in this group was not significantly different. Survival distributions of the RF positive cases were different from that of the other patients (18 versus 25 months median survival); however, this was not statistically significant. These findings indicate that RF in GI cancer patients sera is not rare and can be related mainly to "tumor load," although not considerably affecting survival.

Polyacrolein microspheres as immunoreagents

Polyacrolein microspheres were prepared by radiation polymerization of acrolein in the absence of emulsifying or stabilizing agent. The microspheres had functional surface aldehyde groups permitting covalent binding with antibody in 1 step. The particle size of the microspheres varied with polymerization conditions, especially irradiation temperature. The microsphere antibody conjugates obtained by binding immunoglobulins to polyacrolein microspheres were used to label cells. The reactivity of microsphere antibody conjugates was shown by specific aggregation by antigen.

Chelation of mercury by polymercaptal microspheres: new potential antidote for mercury poisoning

Newly synthesized polymercaptal microspheres of 0.8 +/- 0.02 micron were shown to have a specific and fast intake of mercury compounds over a whole range of pH while maintaining low toxicity. The microspheres bind easily with mercury compounds which are already bound to the biological mercury binders, albumin or cysteine. Mercury was recovered completely from the microspheres by using a solution of thiourea in hydrochloric acid. Due to their high surface area, low toxicity, and strong affinity toward mercury compounds, the microspheres have a potential use as a new oral drug for treatment in cases of mercury poisoning.

Cholera toxin mediated agglutination of ganglioside Gm1 containing phospholipid vesicles and Gm1-coated polystyrene spheres

Quasi-elastic laser light scattering is used to examine the cholera toxin mediated agglutination of ganglioside GM1 containing phospholipid vesicles and Gm1-coated polystyrene spheres. We find that the ability of cholera toxin to agglutinate Gm1-containing phospholipid vesicles depends markedly on the lipid composition of the vesicle, with only those composed of short-chain lipids (C14, C16) being appreciably agglutinated. This is interpreted as due to poor mixing of these lipids with the longer chain gangliosides, resulting in lateral separation of the gangliosides in the membrane bilayer. A simple quantitative model, a modification of that developed by von Schulthess et al. [von Schulthess, G. K., Cohen, R. J., Sakato, N., & Benedek, G. B. (1976a) Immunochemistry 13, 955--962], is developed to describe these agglutination processes. Application of this model to the agglutination of Gm1-coated polystyrene spheres by cholera toxin allows an estimate of a minimum value of 4.5 x 10(4) M-1 for the association constant of cholera toxin for its initial Gm1 receptor.

Rheumatoid factor and monosodium urate crystal-neutrophil interactions in gouty inflammation

A monolayer system was designed to study the interactions between human neutrophils and monosodium urate crystals important in gouty inflammation. The effects of rheumatoid factor on gouty inflammation were then examined in this system and in patients with acute gouty arthritis. Monosodium urate crystal phagocytosis was apparent at 30 min, and this phagocytosis was accompanied by lysosomal enzyme release and decreased neutrophil adherence to plastic petri dishes. Rheumatoid factor did not affect phagocytosis, adherence, or lactic dehydrogenase release and appeared to variably enhance lysosomal enzyme release. Two of 19 acute gouty patients were found to have low titers of rheumatoid factor and, of these, one exhibited mild disease and the other tophaceous destructive disease.

Laboratory diagnosis of rheumatoid diseases

The diagnosis of most collagen diseases requires particular clinical findings. Rheumatoid factor assays are tests commonly used to detect seropositive rheumatoid arthritis. Latex tests are highly sensitive for rheumatoid factors but relatively nonspecific for rheumatoid arthritis, while sheep cell agglutination tests are moderately insensitive for rheumatoid factors but highly specific for rheumatoid arthritis. These tests are not helpful in following the course of the disease, however, since titers remain stable. Serial observations of elevated C-reactive protein levels or ESR may be more helpful in this regard. Specific antibodies have been identified for some collagen diseases, notably the mixed connective tissue disease syndrome, aiding in differential diagnosis.

Interaction of antibody with antigen immobilized on polystyrene latex beads: characterization by density gradient centrifugation

Isopycnic banding by density gradient centrifugation was used to measure density changes in complexes formed by the interaction between antigen and antibody immobilized on polystyrene latex beads (diameter, 0.109 +/- 0.0025 micron). Measurements of density changes allowed calculation of the interacting masses under the given experimental conditions. Interaction equilibrium constants and free energy change for two sets of reactions, bovine IgG and anti-bovine IgG (rabbit) IgG and rabbit IgG and anti-rabbit IgG (goat) IgG systems, were calculated from isopycnic banding density gradient centrifugation runs. The procedure demonstrates a new method of obtaining quantitative information on antigen-antibody interactions.

Immobilization of immunoglobulins on polystyrene latex beads: characterization by density gradient centrifugation

Isopycnic banding by density gradient centrifugation was used to measure density changes in complexes formed by the immobilization of each of four different immunoglobulins (IgG) (bovine, dog, rabbit, and sheep) on polystyrene latex beads (0.109 +/- 0.0025 micrometer diameter). Subtractive measurements of density changes allowed calculation of the mass of immobilized IgG under varying experimental conditions. The immobilization data were correlated with adsorption isotherms which incorporated charge repulsion forces. The effects of pH and NaCl concentration on the immobilization were studied for the latex-bovine IgG system. It was found that the mass of immobilized immunoglobulins was increased from 10 to 20% by removing the IgG from its isoelectric range.

A controlled study of ANA+ RF- arthritis

Thirty (7.5%) of 401 adult rheumatoid arthritis (RA) patients were antinuclear antibody positive (ANA+) and rheumatoid factor negative (RF-), and 15 of 16 patients who were followed for a year or longer remained so. Clinical, other laboratory, and radiographic parameters were compared among this group and 90 matched RA controls divided into ANA+RF+, ANA-RF+, and ANA-RF- groups. All groups were identical, except the ANA-RF- group, which had significantly fewer nodules and less destructive disease than the other three.

Antigen distribution in a latex suspension and its relationship to test sensitivity

Specific aggregation of latex particles due to antigen-antibody reaction occurred only when antigen was latex bound, as found in a study using Escherichia coli 0111:B4 extract. Maximum serological sensitivity was achieved when free antigen was present in a narrow range of ratios with the bound antigen.

A micromethod for evaluating the phagocytic activity of human macrophages by ingestion of radio-labelled polystyrene particles

Studies in vitro of human macrophage function in health and disease have been impeded by the difficulty of obtaining such cells in sufficient number. Unlike animal species, the only readily available source of human macrophages are circulating monocytes. Herein, a method is described whereby the phagocytic rate of small numbers of glass-adherent mononuclear cells can be accurately measured. The method utilizes the ingestion by macrophages of technetium labelled polystyrene particles; both the radiolabel and ingestible substrate are readily available and the labelling process simple and efficient. The phagocytic rate can be expressed as radioactive counts per microgram of cell protein; data is also presented showing that the number of particles ingested per cell can be accurately derived.

Postmyocardial infarction (Dressler's) syndrome: report of a case with immunological and viral studies

A case of PMIX with immunologic and viral studies obtained prior, during, and after a typical exacerbation are reported. Immunologic studies indicated the presence of humoral antiheart autoantibodies, and an increase in the number and proportion of lymphocytes containing surface IgG immunoglobulin during acute activity. Viral studies were negative. Previously reported immunologic and viral data, as well as etiology and pathogenesis of PMIS are discussed.