Nature of anaemia in rheumatoid arthritis. III. Changes in the bone marrow and their relation to other features of the disease

Periarticular osteoporosis of the forearm correlated with joint destruction and functional impairment in patients with rheumatoid arthritis

The relationship between periarticular osteoporosis in the distal forearm and joint destruction or functional impairment in patients with rheumatoid arthritis (RA) is not sufficiently elucidated. From a single institutional cohort study, we found a strong correlation between periarticular forearm bone mineral density (BMD) and joint destruction or functional impairment.

INTRODUCTION

This study was conducted to investigate (1) the difference between various periarticular regions of interest (ROIs) of BMD of the forearm, (2) the correlation between periarticular forearm BMD and joint destruction and physical function, (3) the independent variables for predicting BMD of the forearm, and (4) the forearm BMD of different ROIs in the early stage of RA.

METHODS

We conducted a cross-sectional study in an RA cohort. Measurements included BMD of the distal forearm, joint destruction of the hands assessed by modified total Sharp score (mTSS), functional impairment assessed by a health assessment questionnaire (HAQ), and other clinical data. Variables affecting the forearm BMD values were analyzed by correlation and stepwise regression analyses.

RESULTS

Of the 405 patients enrolled in the present study, 370 (average age; 62.9 years) were identified as having definite RA with a complete set of data. BMD in the distal end of the forearm (BMDud) was significantly reduced compared with that in the distal third of the forearm (BMD1/3). In a stepwise regression analysis, the mTSS in BMD1/3 was an independent predicting variable, while age and partial HAQ scores associated with the upper extremity were common independent variables in BMDud and BMD1/3. BMDud was significantly less than BMD1/3, even in patients with a short duration of the disease. BMD1/3 was significantly less in non-remission group compared with that in remission group in patients with a short duration of the disease.

CONCLUSION

Periarticular BMD in the distal forearm is closely correlated with joint destruction and functional impairment in RA. Periarticular BMD in the distal forearm may be already reduced at the clinical manifestation of the disease.

Is rheumatoid arthritis a B-cell haematological disease with a predilection for the joints? Following the B cell thread to its logical conclusion

B-cell depleting therapy (BCDT) is effective in suppressing synovitis and erosions in rheumatoid arthritis suggesting that a cell of the B-lymphocyte lineage is critical in the pathogenesis of this disease. Non-Hodgkins lymphoma (NHL) also responds to BCDT but multiple myeloma (MM), does not as cells have differentiated beyond the CD20-bearing stage. However, there are similarities between B-NHL, MM and RA that suggest all 3 conditions could be initiated and perpetuated by the same cellular players. Numerous plasma cells and B cells are present within rheumatoid synovial membrane, and subarticular bone where they contribute to osteitis. On MRI scans this appears as bone oedema, which has been demonstrated to precede the development of bone erosions. Plasma cell clonality has been detected within RA synovial membrane and bone marrow. It is proposed that RA could represent a "forme fruste" of a B cell neoplastic condition, with production of autoantibodies that target a self-antigen within the joint. The activation of rheumatoid bone osteoclasts by anticitrullinated protein antibodies supports this theory. The erosions of RA would have parallels with the lytic lesions of MM but autoantigen targeting dictates that erosions occur at joint margins. This theory is discussed from rheumatologic and haematologic perspectives.

Inflammatory lesions in the bone marrow of rheumatoid arthritis patients: a morphological perspective

The synovial tissue stands at the epicenter of joint pathology in rheumatoid arthritis (RA). As a primary target of the disease, studies on the synovium have provided invaluable insights into the mechanisms involved in disease pathogenesis. Recent work has, however, revealed the importance of a previously unseen anatomic compartment in direct contact with the joint space, namely the subchondral bone marrow. Bone marrow edema (BME) visible on magnetic resonance imaging (MRI) is clinically meaningful in both early and late RA as it associates with future development of bone erosions and poor functional outcomes. Although the histopathologic correlates of MRI-based BME in early RA remain obscure, studies in advanced disease are consistent in describing lymphocytic inflammatory infiltrates within the subchondral marrow cavity of affected joints. In this review, we discuss the nature of bone marrow lesions in patients with RA, analyze their relationship with synovitis, and explore their potential contribution to the pathological processes of the disease.

Ferastral in the treatment of patients with inflammatory anaemia

An investigation has been performed with a new parenteral iron preparation, iron-poly-(sorbitol-gluconic acid) complex (Ferastral) in the treatment with iron deficiency anaemia associated with inflammatory diseases, mainly rheumatoid arthritis. Fifteen moderately anaemic patients entered into the trial. These patients constituted a special group in whom the MCHCs were subnormal. Observations were made concerning the occurrence of side-effects. Particular attention was paid to those-side-effects which are known to be associated with the use of parenteral iron preparations in the treatment of rheumatoid subjects. Ferastral was administered by intramuscular by intramuscular injection. The single doses given on any one occasion varied from a minimum of 100 mg to a maximum of 500 mg, divided into two separate injections. The results of therapy, measured at eight weeks, showed significant increases in haemoglobin concentrations. Increases in erythrocyte count, MCHC and serum-iron concentration were also found. There were no signs of acute toxic effects with Ferastral and in no patient was there exacerbation of arthritis as has been previously reported with iron-dextran.

Quantitative photometrical assessment of iron deposits in synovial membranes in different joint diseases

We investigated 86 synovial membranes from patients suffering either from rheumatoid arthritis (RA) or osteoarthritis (OA). Iron deposits in the synovial membrane were stained by the Prussian blue reaction, and the amount of stained iron was quantitatively assessed by microscope photometry. We found a statistically significant increase in iron deposits in the synovial membrane of RA patients when compared to OA patients. The amount of iron deposits correlated with the histological subtype of synovitis, those presenting with more exudative and proliferative features showing greater amounts of iron deposits. We also observed an inverse correlation between the haemoglobin concentration and erythrocytes in the serum and the amount of iron in the synovial membrane. From our data we concluded that iron deposits in the synovial membrane can contribute by several mechanisms, including activation of oxygen radicals, to the chronic inflammatory reaction in RA synovitis.

The pathogenesis of anemia in rheumatoid arthritis: a clinical and laboratory analysis

Principal concepts concerning the anemia of RA are summarized in Tables 7 and 8. These concepts have been validated by our analysis of 93 anemic RA patients and by our review of the literature. The fact that anemia in RA may have one or more etiologies, occasionally in the same patient, mandates a reasoned approach to the analysis of anemia in every RA patient in whom it may occur. In particular, iron deficiency is common and determination of bone marrow iron content via an aspirate may be required for a definitive diagnosis. In those RA patients with anemia of chronic disease, the best therapy remains control of the underlying disease, most commonly with second line drugs and/or corticosteroids. The place for recombinant erythropoietin in the therapy of this anemia has not been defined; one specific role for erythropoietin may be in the preparation of RA patients for elective surgery, particularly hip arthroplasty, where correction of the anemia may either obviate the need for transfusion or may allow for donation of blood for purposes of autologous transfusion perioperatively. The pathogenesis of the anemia of chronic disease, as seen in RA anemia, is not completely understood. Inflammatory mediators, particularly the cytokines, appear to be important factors in the impairment of erythropoiesis. The mechanism by which these cytokines impair erythroid progenitor growth and hemoglobin production in developing erythrocytes is an important area for future study.

Clinical spectrum of the upper gastrointestinal effects of nonsteroidal anti-inflammatory drugs. Natural history, symptomatology, and significance

Nonsteroidal anti-inflammatory drugs (NSAIDs) relieve rheumatic pain and are in extensive use. Symptomatic complications of NSAIDs requiring the discontinuation of their use occur in 2 to 10 percent of patients with rheumatic diseases in sharp contrast to the common asymptomatic problems of gastroduodenal erosions, ulcerations, and bleeding, with resulting anemia in more than 40 percent of these patients. Opinions concerning the clinical significance of these complications are not uniform. The natural history of the effects of NSAIDs on the gastroduodenal mucosa reveals a sequence of initial subepithelial hemorrhage over a 24-hour period followed by gastroduodenal erosions and ulcerations in the next two weeks. From one week to three months, gastroduodenal erosions and ulcerations disappear in about half of the patients as an adaptation to continuing NSAID ingestion occurs. Hemorrhage may occur at any time in most patients and in a small minority (1 percent) it is massive. Non-aspirin NSAIDs (NANSAIDs) exhibit significantly fewer complications than do aspirin. These complications, however, demand considerable clinical attention and are ordered in a constant hierarchy, suggesting variable risks of complications among agents. NSAIDs are a blessing for those who have chronic pain, but that blessing does not prevent significant asymptomatic complications in the same patients. Prophylaxis for high-risk groups, such as women over the age of 65 years, should be subjected to study.

Immunological aspects of the anemia of rheumatoid arthritis

In order to investigate the cause of the anemia concomitant with rheumatoid arthritis (RA), we examined, using the erythroid colony assay of human bone marrow colony-forming units-erythroid (CFU-e) and burst-forming units-erythroid (BFU-e), the effects of the patients' serum and peripheral blood T lymphocytes on the CFU-e-derived colonies. The counts of erythroid colonies of RA patients were markedly lower than those of human control subjects [CFU-e: control 152.9 +/- 30.6 (n = 19), RA 51.1 +/- 13.6 (n = 7), t = 7.66567, p less than 0.01; BFU-e: control 25.2 +/- 5.9 (n = 5), RA 12.6 +/- 2.6 (n = 7), t = 4.574, p less than 0.01]. The serum from two out of seven RA patients slightly inhibited the formation of CFU-e-derived colonies of human control subjects (t = 2.31, 0.05 less than p less than 0.1); however, the serum from the other five RA patients did not significantly inhibit human control erythroid colony formation as compared with human control serum (t = 0.981, 0.3 less than p less than 0.4). On the other hand, peripheral blood T lymphocytes of the patients markedly inhibited the formation of CFU-e-derived colonies of the control subjects as compared with peripheral blood T lymphocytes from human control subjects (t = 4.24, p less than 0.01). The above-mentioned results suggest that the peripheral blood T lymphocytes of RA patients might play a role as one of the causes of the concomitant anemia of RA patients.

Anemia associated with rheumatoid disease. Inverse correlation between erythropoiesis and both IgM and rheumatoid factor levels

Cell culture techniques were used to evaluate the number of erythroid colonies formed by circulating progenitor cells from 24 patients with rheumatoid disease and controls. A highly significant inverse correlation was demonstrated between erythroid colony counts and serum IgM and rheumatoid factor concentrations in the rheumatoid patients. The potential role of these factors in the pathogenesis of the anemia of rheumatoid disease is discussed.

Evaluation of pindolol in the treatment of hypertension

Twenty hypertensive patients were treated for 15 weeks with pindolol, a new anti-hypertensive agent. Blood pressure while resting and after standing was reduced in all patients whether previously treated with an antihypertensive agent or not. All patients completed the study and no side-effects were reported. Laboratory tests showed no abnormalities and pindolol was very well tolerated in all patients. The dose of other antihypertensive agents was reduced in 7 patients.

Haem biosynthesis studied in patients with rheumatoid arthritis

In a study of the urinary excretion of haem precursors in patients with rheumatoid arthritis, iron-deficiency anaemia, and in healthy controls, certain differences were found. In iron-deficiency anaemia the excretion of both porphobilinogen and delta-aminolevulinic acid was increased, whereas in patients with rheumatoid arthritis only the porphobilinogen excretion was increased.A further study on the erythrocyte activity of delta-aminolevulinic acid dehydrase showed a higher activity in the erythrocytes from patients with rheumatoid arthritis compared with healthy controls.

Serum iron and iron kinetics in coalworkers with complicated pneumoconiosis

Chan, B. W. B. (1969).Brit. J. industr. Med.,26, 65-70. Serum iron and iron kinetics in coalworkers with complicated pneumoconiosis. Twenty-three patients with complicated pneumoconiosis were studied, and compared with 16 patients of similar age with chronic non-specific lung disease. In seropositive cases (Rose Waaler titre higher than 1: 32) the serum iron, total iron binding capacity (T.I.B.C.), and the serum iron/T.I.B.C.% were all significantly decreased. In seronegative cases only the T.I.B.C. was significantly decreased. Low serum iron levels were found to be associated with a high iron clearance rate, so that the total iron transport rate was normal or slightly increased. The proportion of circulating plasma iron utilized for effective red cell production was found to be normal. These findings are, in general, similar to those in rheumatoid arthritis and suggest that iron mobilization or transport may be defective but that erythropoiesis is not depressed.

Anaemia of rheumatoid arthritis and iron therapy

Images