Mechanisms of depressed delayed-type hypersensitivity in rheumatoid arthritis: the role of protein energy malnutrition

T cell receptor signaling in the differentiation and plasticity of CD4+ T cells

CD4⁺ T cells are critical components of the adaptive immune system. The T cell receptor (TCR) and co-receptor signaling cascades shape the phenotype and functions of CD4⁺ T cells. TCR signaling plays a crucial role in T cell development, antigen recognition, activation, and differentiation upon recognition of foreign- or auto-antigens. In specific autoimmune conditions, altered TCR repertoire is reported and can predispose autoimmunity with organ-specific inflammation and tissue damage. TCR signaling modulates various signaling cascades and regulates epigenetic and transcriptional regulation during homeostasis and disease conditions. Understanding the mechanism by which coreceptors and cytokine signals control the magnitude of TCR signal amplification will aid in developing therapeutic strategies to treat inflammation and autoimmune diseases. This review focuses on the role of the TCR signaling cascade and its components in the activation, differentiation, and plasticity of various CD4⁺ T cell subsets.

ZAP70, too little, too much can lead to autoimmunity*

Establishing both central and peripheral tolerance requires the appropriate TCR signaling strength to discriminate self‐ from agonist‐peptide bound to self MHC molecules. ZAP70, a cytoplasmic tyrosine kinase, directly interacts with the TCR complex and plays a central and requisite role in TCR signaling in both thymocytes and peripheral T cells. By studying ZAP70 hypomorphic mutations in mice and humans with a spectrum of hypoactive or hyperactive activities, we have gained insights into mechanisms of central and peripheral tolerance. Interestingly, both hypoactive and hyperactive ZAP70 can lead to the development of autoimmune diseases, albeit through distinct mechanisms. Immature thymocytes and mature T cells rely on normal ZAP70 function to complete their development in the thymus and to modulate T cell responses in the periphery. Hypoactive ZAP70 function compromises key developmental checkpoints required to establish central tolerance, allowing thymocytes with potentially self‐reactive TCRs a greater chance to escape negative selection. Such ‘forbidden clones’ may escape into the periphery and may pose a greater risk for autoimmune disease development since they may not engage negative regulatory mechanisms as effectively. Hyperactive ZAP70 enhances thymic negative selection but some thymocytes will, nonetheless, escape negative selection and have greater sensitivity to weak and self‐ligands. Such cells must be controlled by mechanisms involved in anergy, expansion of Tregs, and upregulation of inhibitory receptors or signaling molecules. However, such potentially autoreactive cells may still be able to escape control by peripheral negative regulatory constraints. Consistent with findings in Zap70 mutants, the signaling defects in at least one ZAP70 substrate, LAT, can also lead to autoimmune disease. By dissecting the similarities and differences among mouse models of patient disease or mutations in ZAP70 that affect TCR signaling strength, we have gained insights into how perturbed ZAP70 function can lead to autoimmunity. Because of our work and that of others on ZAP70, it is likely that perturbations in other molecules affecting TCR signaling strength will be identified that also overcome tolerance mechanisms and cause autoimmunity. Delineating these molecular pathways could lead to the development of much needed new therapeutic targets in these complex diseases.

COVID-19 vaccination and antirheumatic therapy

The coronavirus disease 2019 (COVID-19) vaccination will be the largest vaccination programme in the history of the NHS. Patients on immunosuppressive therapy will be among the earliest to be vaccinated. Some evidence indicates immunosuppressive therapy inhibits humoral response to the influenza, pneumococcal and hepatitis B vaccines. The degree to which this will translate to impaired COVID-19 vaccine responses is unclear. Other evidence suggests withholding MTX for 2 weeks post-vaccination may improve responses. Rituximab has been shown to impair humoral responses for 6 months or longer post-administration. Decisions on withholding or interrupting immunosuppressive therapy around COVID-19 vaccination will need to be made prior to the availability of data on specific COVID-19 vaccine response in these patients. With this in mind, this article outlines the existing data on the effect of antirheumatic therapy on vaccine responses in patients with inflammatory arthritis and formulates a possible pragmatic management strategy for COVID-19 vaccination.

Reporters of TCR signaling identify arthritogenic T cells in murine and human autoimmune arthritis

How arthritis-causing T cells trigger rheumatoid arthritis (RA) is not understood since it is difficult to differentiate T cells activated by inflammation in arthritic joints from those activated through their T cell antigen receptor (TCR) by self-antigens. We developed a model to identify and study antigen-specific T cell responses in arthritis. Nur77—a specific marker of TCR signaling—was used to identify antigen-activated T cells in the SKG arthritis model and in patients with RA. Nur77 could distinguish highly arthritogenic and autoreactive T cells in SKG mice. The enhanced autoreactivity was associated with increased interleukin-6 (IL-6) receptor signaling, likely contributing to their arthritogenicity. These data highlight a functional correlate between Nur77 expression, arthritogenic T cell populations, and heightened IL-6 sensitivity in SKG mice with translatable implications for human RA.

How pathogenic cluster of differentiation 4 (CD4) T cells in rheumatoid arthritis (RA) develop remains poorly understood. We used Nur77—a marker of T cell antigen receptor (TCR) signaling—to identify antigen-activated CD4 T cells in the SKG mouse model of autoimmune arthritis and in patients with RA. Using a fluorescent reporter of Nur77 expression in SKG mice, we found that higher levels of Nur77-eGFP in SKG CD4 T cells marked their autoreactivity, arthritogenic potential, and ability to more readily differentiate into interleukin-17 (IL-17)–producing cells. The T cells with increased autoreactivity, nonetheless had diminished ex vivo inducible TCR signaling, perhaps reflective of adaptive inhibitory mechanisms induced by chronic autoantigen exposure in vivo. The enhanced autoreactivity was associated with up-regulation of IL-6 cytokine signaling machinery, which might be attributable, in part, to a reduced amount of expression of suppressor of cytokine signaling 3 (SOCS3)—a key negative regulator of IL-6 signaling. As a result, the more autoreactive GFP^hi CD4 T cells from SKGNur mice were hyperresponsive to IL-6 receptor signaling. Consistent with findings from SKGNur mice, SOCS3 expression was similarly down-regulated in RA synovium. This suggests that despite impaired TCR signaling, autoreactive T cells exposed to chronic antigen stimulation exhibit heightened sensitivity to IL-6, which contributes to the arthritogenicity in SKG mice, and perhaps in patients with RA.

Latent tuberculosis infection in patients with rheumatic diseases

Most people infected by Mycobacterium tuberculosis (Mtb) do not have any signs or disease symptoms, a condition known as latent tuberculosis infection (LTBI). The introduction of biological agents, mainly tumor necrosis factor (TNF) inhibitors, for the treatment of immune-mediated diseases such as Rheumatoid Arthritis (RA) and other rheumatic diseases, increased the risk of reactivation of LTBI, leading to development of active TB. Thus, this review will approach the aspects related to LTBI in patients with rheumatologic diseases, especially those using iTNF drugs. For this purpose it will be considered the definition and prevalence of LTBI, mechanisms associated with diseases and medications in use, criteria for screening, diagnosis and treatment. Considering that reactivation of LTBI accounts for a large proportion of the incidence of active TB, adequate diagnosis and treatment are crucial, especially in high-risk groups such as patients with rheumatologic diseases.

Identification of latent tuberculosis infection in rheumatic patients under consideration for treatment with anti-TNF-α agents

INTRODUCTION

Immunosuppressive therapy with anti-tumour necrosis factor-α (TNF-α) agents in rheumatic patients modulates the immune system and may increase the risk of reactivating infections that are normally maintained in a latent state, such as tuberculosis. The purpose of this study was to analyse the value of QuantiFERON TB Gold In-Tube (QFT IT) and tuberculin skin test (TST) in BCG vaccinated patients with rheumatoid arthritis and ankylosing spondylitis who were qualified to receive TNF-α blockers.

MATERIAL AND METHODS

Ninety patients with rheumatoid arthritis and ankylosing spondylitis were included in the study. The control group consisted of 20 healthy participants. Chest X-ray, TST and QFT IT were carried out in all persons.

RESULTS

In rheumatic patients positive results of QFT IT and TST tests were identified in 15 cases (16.7%) whereas negative results of both tests were detected in 56 cases (62.2%). In the group of examined patients, 11 (12.2%) had QFT IT-/TST+ test results. In patients with QFT IT+/TST- status one active tuberculosis case was detected. In the control group QFT IT positive results were found in 4 cases (20%) and TST positive in 11 cases (55%). Treatment with TNF-α blockers was introduced in 26 rheumatology patients with the following test status: 3 with QFT IT+/TST+; 20 with QFT IT-/TST-; 3 with QFT IT-/TST+.

CONCLUSIONS

In the BCG vaccinated population the QFT IT assay may potentially improve the identification and selection for therapy for latent TB infection before treatment with anti-TNF agents.

Challenges in Diagnosing Latent Tuberculosis Infection in Patients Treated with Tumor Necrosis Factor Antagonists

Reactivation of latent tuberculosis infection (LTBI) is well recognized as an adverse event associated with anti-tumor necrosis factor-α (anti-TNF-α) therapy. The strengths and weaknesses of current techniques for detecting LTBI in patients with chronic inflammatory diseases such as rheumatoid arthritis (RA) and psoriasis have not been fully examined. T cell hyporesponsiveness due to immunosuppression caused by illness or drugs, referred to as anergy, may produce false-negative tuberculin skin test (TST) and interferon-γ release assay (IGRA) results. The literature suggests that anergy may influence screening performance of TST and IGRA tests in candidates for anti-TNF-α therapy. Conversely, the potential for false-positive TST and IGRA results must be considered, as treatment for LTBI may be associated with significant morbidity. This review examines the reliability issues related to LTBI diagnostic testing and provides practical direction to help prevent LTBI reactivation and facilitate successful anti-TNF-α treatment.

Immunization responses in rheumatoid arthritis patients treated with rituximab: results from a controlled clinical trial

OBJECTIVE

To examine immunization responses in patients with rheumatoid arthritis (RA) treated with rituximab and to investigate the effects of rituximab-induced CD20+ B cell depletion on immune responses to tetanus toxoid (T cell-dependent antigen), pneumococcal polysaccharide (T cell-independent antigen), and keyhole limpet hemocyanin (KLH) (neoantigen) and on delayed-type hypersensitivity (DTH).

METHODS

In a controlled trial, we enrolled 103 patients with active RA receiving a stable dose of methotrexate (MTX). Tetanus toxoid, pneumococcal polysaccharide, and KLH vaccines as well as a Candida albicans skin test were administered to 1 group of patients receiving rituximab plus MTX (called rituximab-treated patients) for 36 weeks and to 1 group of patients receiving MTX alone for 12 weeks. The primary end point was the proportion of patients with a >or=4-fold rise in antitetanus IgG levels. Antitetanus, antipneumococcal, and anti-KLH serum IgG levels were measured prior to and 4 weeks following vaccine administration. The DTH response to C albicans was measured 2-3 days following placement.

RESULTS

Responses to tetanus toxoid vaccine (>or=4-fold rise) were similar in both groups (39.1% of rituximab-treated patients and 42.3% of patients treated with MTX alone). The ability to maintain a positive DTH response to the C albicans skin test was comparable in both groups (77.4% of rituximab-treated patients and 70% of patients treated with MTX alone), showing no effect of rituximab treatment. Rituximab-treated patients had decreased responses to pneumococcal polysaccharide vaccine (57% of patients had a 2-fold rise in titer in response to >or=1 serotype, compared with 82% of patients treated with MTX alone) and to KLH vaccine (47% of patients had detectable anti-KLH IgG, compared with 93% of patients treated with MTX alone).

CONCLUSION

Recall responses to the T cell-dependent protein antigen tetanus toxoid as well as DTH responses were preserved in rituximab-treated RA patients 24 weeks after treatment. Responses to neoantigen (KLH) and T cell-independent responses to pneumococcal vaccine were decreased, but many patients were able to mount responses. These data suggest that polysaccharide and primary immunizations should be administered prior to rituximab infusions to maximize responses.

The impact of hormone replacement therapy on humoral and cell-mediated immune responses in vivo in post-menopausal women with rheumatoid arthritis

It is well known that oestrogen has immunomodulatory properties. We have previously shown disease ameliorating effects of hormone replacement therapy (HRT) in post-menopausal women with rheumatoid arthritis (RA). The aim of this study was to investigate the effects of HRT and the patients inflammatory state on humoral and cell-mediated immune responses. Eighty-eight post-menopausal RA women were allocated to receive HRT (oestradiol and noretisterone acetate), vitamin D3 and calcium or vitamin D3 and calcium alone in a 2-year randomized controlled trial. Immunoglobulins (IgM, IgG and IgA) in serum were measured by nephelometry and rheumatoid factor (RF) concentration by enzyme-linked immunosorbent assay. Immunization with influenza vaccine was performed to quantitate humoral response to recall antigen and tuberculin skin test with purified protein derivative (PPD) to test T-cell-mediated immune response. These immune related measures were correlated with demographic and disease-related variables. HRT during 2 years did not alter concentrations of Ig, RF, IgM response to influenza vaccine or the PPD reaction. The increase in IgM against influenza vaccine was significantly positively correlated with signs of disease activity; C-reactive protein, disease activity score 28 and inversely with haemoglobin. In contrast, PPD reactivity was inversely associated with disease activity. In conclusion, long-term HRT in RA does not influence Ig or autoantibody concentrations in serum and has no significant impact on humoral and cell-mediated immune responses to recall antigens. Interestingly, high disease activity was associated to increased humoral but decreased cell-mediated immune responses irrespectively of hormone treatment.

Diagnosis and treatment of latent tuberculosis infection in arthritis patients treated with tumor necrosis factor antagonists in Korea

Tumor necrosis factor (TNF) is essential for host defense against Mycobacterium tuberculosis, and the risk of reactivation of latent tuberculosis infection (LTBI) increases with anti-TNF therapy. This study estimated the prevalence of LTBI and evaluated the safety and completion rate of short-course therapy with isoniazid plus rifampin for 3 months to treat LTBI in a cohort of Korean arthritis patients before initiating anti-TNF therapy. We retrospectively studied the files of 112 consecutive patients to evaluate LTBI before starting anti-TNF drugs. Screening tests were performed, including a tuberculin skin test and chest radiography. LTBI treatment was indicated in 41 patients (37%). Of these, three patients refused the LTBI treatment. Of the 38 patients who underwent LTBI treatment, 36 (95%) took isoniazid plus rifampin for 3 months. Six patients (16%) showed transient elevations of liver enzymes during the LTBI treatment. Overall, 35 patients (92%) completed the LTBI treatment as planned. In conclusion, LTBI was diagnosed in one-third of Korean arthritis patients before initiating anti-TNF therapy. A high percentage of these patients completed 3 months of LTBI treatment with isoniazid plus rifampin without serious complications.

Consideration of the risk and treatment of tuberculosis in patients who have rheumatoid arthritis and receive biologic treatments

Evidence supports the association of tuberculosis (TB) with tumor necrosis factor inhibitor therapy in patients who have rheumatoid arthritis. There seem to be differential risks of TB with the currently available inhibitors. Screening for latent TB infection with purified protein derivative is indicated for patients who are being considered for treatment; it seems to be effective in reducing the occurrence of TB in treated patients.

Granulomatous infectious diseases associated with tumor necrosis factor antagonists

The relationship between the use of tumor necrosis factor antagonists and onset of granulomatous infection was examined using data collected through the Adverse Event Reporting System of the US Food and Drug Administration for January 1998-September 2002. Granulomatous infections were reported at rates of approximately 239 per 100,000 patients who received infliximab and approximately 74 per 100,000 patients who received etanercept (P<.001). Tuberculosis was the most frequently reported disease, occurring in approximately 144 and approximately 35 per 100,000 infliximab-treated and etanercept-treated patients, respectively (P<.001). Candidiasis, coccidioidomycosis, histoplasmosis, listeriosis, nocardiosis, and infections due to nontuberculous mycobacteria were reported with significantly greater frequency among infliximab-treated patients. Seventy-two percent of these infection occurred < or =90 days after starting infliximab treatment, and 28% occurred after starting etanercept treatment (P<.001). These data indicate a risk of granulomatous infection that was 3.25-fold greater among patients who received infliximab than among those who received etanercept. The clustering of reports shortly after initiation of treatment with infliximab is consistent with reactivation of latent infection.

Nutritional status in patients with rheumatoid arthritis

BACKGROUND

Some chronic diseases have been associated to an impairment of nutritional status.

OBJECTIVE

To analyze nutritional status and its relation to dietary intake, disease activity and treatment in rheumatoid arthritis.

PATIENTS AND METHODS

We have included 93 patients (43 men and 50 women) and 93 age- and sex-matched healthy controls. The assessment of nutritional status included anthropometric (body mass index, tricipital skin fold and midarm muscular circumference) and biochemical (serum albumin, prealbumin and retinol binding protein) parameters. Dietary intake was calculated from a food frequency questionnaire. As a measure of disease activity, we used the Health Assessment Questionnaire, Ritchie index, tender and swollen joint count and C-reactive protein. Statistical analysis was performed in the whole series and in every functional class.

RESULTS

In the whole series, midarm muscular circumference and serum albumin were significantly lower in patients than in controls. All anthropometric parameters and serum albumin were significantly lower in patients in functional class IV than in their respective controls. The dietary intake of energy, carbohydrates, vegetal proteins and lipids was higher in patients than in controls. Midarm muscular circumference and serum albumin had a significant inverse relation with disease activity parameters; body mass index, midarm muscular circumference and serum albumin correlated inversely with the cumulative dose of glucocorticoids.

CONCLUSIONS

Patients with rheumatoid arthritis in functional class IV have an impairment of nutritional status without a deficient dietary intake. The differences found in other functional classes are explained by rheumatoid arthritis itself. Nutritional parameters are related to disease activity and glucocorticoid treatment.

Reduced in vivo cell-mediated immune responses to mumps, tuberculin, and streptokinase/streptodornase but not to Candida albicans in oral lichen planus

Oral lichen planus is considered to be a T-cell-mediated disease. The purpose of this study was to investigate the capacity of T-lymphocytes in oral lichen planus patients to respond to a number of commonly encountered environmental antigens in vivo. To do this, we assessed dermal delayed-type hypersensitivity responses to mumps, streptokinase/streptodornase, Candida albicans, and purified protein derivative of tuberculin (PPD) in 17 oral lichen planus patients and in matched controls. Reduced induration in response toward mumps, PPD, and streptokinase/streptodornase was demonstrated in oral lichen planus patients compared with controls. In addition, the total sum of induration diameters was decreased in the patients. However, C. albicans stimulation resulted in similar levels of response in both groups. The differences in induration size between matched patients and controls for mumps and PPD were thus significantly greater than the corresponding differences for the C. albicans antigen. This suggests that a selective difference in the response to these antigens exists in oral lichen planus patients. The results may point to a loss of memory T-helper function to infrequently encountered environmental antigens, represented by mumps, PPD, and streptokinase/streptodornase, contrarily to memory function to common antigens (C. albicans), which seem to be unaffected.

Nutritional status and performance capacity in internal medical patients

The nutritional status (3 anthropometric records, serum albumin and delayed cutaneous hypersensitivity (DCH)), recent weight loss, dynamometric capacity and mood were assessed in 205 recently admitted non-cancer internal medical patients. 20% of the subjects were classified as malnourished (3 of the 5 nutritional variables below the reference range). The occurrence of malnutrition was higher (1/3) in multiple organ dysfunction or chronic respiratory disease. In order to reduce the risk of overestimating malnutrition, the data for serum albumin and DCH were omitted when they appeared to be influenced by non-nutritional factors. Disease duration >2 years, old age and multiple organ dysfunction were independently related to malnutrition. Serum albumin correlated more strongly with the acute phase reactant, serum acid glycoprotein (r = 0.33, P < 0.001) than with the anthropometric variables (r < 0.24). Recalled recent weight loss >5% was found in 34% of the malnourished subjects. Malnourished, in comparison to well nourished patients, exhibited reduced (p < 0.05) recordings for hand grip strength, peak expiratory flow and time of ambulation. Depressive tendencies were seen in malnourished women (p < 0.05).

Nutrient intake and nutritional status in children with juvenile chronic arthritis

Nutrient intake and nutritional status were assessed in 15 children with juvenile chronic arthritis (JCA) and in 17 healthy controls. Anthropometric measurements were similar in children with pauciarticular JCA and in controls, whereas weight (p = 0.05) and upper arm muscle area (UAMA) (p less than 0.01) were reduced in children with polyarticular JCA. Compared with healthy controls the concentrations of hemoglobin, serum iron and serum zinc were reduced in the children with polyarticular JCA (p less than 0.01) and serum copper was increased (p less than 0.01). In the patients the concentrations of hemoglobin, serum iron and serum zinc correlated negatively with erythrocyte sedimentation rate (ESR), whereas serum copper correlated positively. Impaired nutritional status was found in the children with polyarticular JCA in spite of increased energy and protein intake. In this group of patients the dietary intake of calcium was also found to be reduced.

Rheumatoid arthritis, food, and allergy

One of the most promising lines of research on the etiology and pathogenesis of rheumatoid arthritis (RA) is its association with the genetically determined MHC class II antigens. The function of these macromolecules, presentation of antigens to the T-helper cells, supports the possibility that external antigens influence RA. We review available literature concerning the relationship between RA and food. Circumstantial evidence suggests that some foods or food components might influence subgroups of RA patients, although many of the publications on this subset do not meet acceptable standards of modern medical research.

Impaired delayed type cutaneous hypersensitivity in rheumatoid arthritis reversed by chrysotherapy

A prospective 24 week study of 31 patients with active rheumatoid arthritis (18 women, 13 men) was undertaken to determine whether weekly intramuscular sodium aurothiomalate (gold) would influence delayed type cutaneous hypersensitivity (DTH) and other indices of cell mediated immunity. DTH to seven recall antigens was measured by Multitest on three occasions during the study. Twenty five patients completed the study. At entry 13 patients (12 female) were anergic, and no significant correlations were found between DTH and other clinical and immunological indices. Women showed a significantly greater depression of DTH than men. At week 24 only three of the patients were anergic with significant increase in mean DTH score being noted particularly to tuberculin, candida, and streptococcus. Improvement in DTH was observed in both gold responders and non-responders. In conclusion, patients with active rheumatoid arthritis show impairment of DTH, which is reversed by chrysotherapy. This effect is most apparent in women and appears to be relatively independent of the clinical response.

Malnutrition in rheumatoid arthritis

A nutrition study was conducted in thirty-eight hospitalized rheumatoid arthritis (RA) patients. Twenty-seven (71.1%) had a high likelihood of malnutrition (LOM). Laboratory and anthropometric data suggest that multiple vitamin, calory, and protein deficiencies are present. Age, female sex and a poor grip strength correlated with some indices of malnutrition. Fifteen of 18 patients with a high LOM had a bad outcome whereas 3 of 7 patients with a low LOM had a bad outcome. Malnutrition per se may be a contributing factor to increased morbidity and mortality in RA.

Lymphokine-activated killer cell activity in rheumatoid arthritis

The lymphokine-activated killer (LAK) cell activity in the peripheral blood of 23 patients with rheumatoid arthritis has been studied. Two control groups comprised (a) nine patients with another chronic inflammatory disease (sarcoidosis) and (b) 19 normal healthy volunteers. The LAK activity induced by human recombinant IL-2 was very similar in controls and patients with rheumatoid arthritis but was significantly decreased in patients with sarcoidosis, although the frequency of LAK-cell precursors measured using a limiting dilution assay was comparable in all three groups. The DNA synthetic response of peripheral blood mononuclear (PBM) cells to IL-2 was slightly decreased in patients with both rheumatoid arthritis and sarcoidosis as compared to controls, but this decrease was not statistically significant. Spontaneous DNA synthesis in PBM cells cultured in the absence of IL-2 was essentially identical in all three groups. We conclude on the basis of these results that the higher risk of non-Hodgkin's lymphomas in patients with rheumatoid arthritis cannot be attributed to an impairment of LAK activity. Furthermore, the doses of gamma-irradiation, which abolished the 'background' cytotoxicity of PBM cells cultured without IL-2 and also blocked effectively both spontaneous and exogenous IL-2-dependent DNA synthesis, had little effect on the generation of LAK activity. These observations are discussed in regard to the role of non-specific cytotoxic cells and the therapeutic efficacy of antiproliferative drugs in rheumatoid arthritis.

Atopy and rheumatoid arthritis

The prevalence of rheumatoid arthritis (RA) was studied among 266 atopic patients attending an allergy clinic. Two patients had definite RA, a prevalence similar to that seen in the general population. We also studied the prevalence of atopy (positive skin-prick tests) and diseases associated with atopy among forty patients with RA and forty age- and sex-matched controls. The two groups had a similar prevalence of atopy (5 RA patients, nine controls) and atopic diseases (fourteen RA patients, fourteen controls) and they did not differ with respect to blood eosinophil counts or total serum IgE. Positive RAST tests to inhaled allergens were found in three RA patients and five controls and all patients had negative RAST tests to milk and egg. It was concluded that patients with rheumatoid arthritis have a normal prevalence of atopy and atopic diseases and we found no evidence that allergic factors contributed to the arthritis of the forty RA patients in the study.

Mammary gigantism and D-penicillamine

Mammary gigantism is a rare complication of D-penicillamine treatment. We report a further case with pathological and endocrine details together with a review of the seven cases previously reported and possible mechanisms.