Related Experiment Video
Updated: Oct 11, 2025
An Adoptive Transfer Model of Rheumatoid Arthritis in Mice
Published on: June 6, 2025
Development of Rheumatoid Arthritis During Anti-Interleukin-5 Therapy in a Patient with Refractory Chronic
Hiroki Kawabata1, Minoru Satoh2, Kazuhiro Yatera1
1Department of Respiratory Medicine, University of Occupational and Environmental Health, Kitakyushu, Fukuoka, 807-8555, Japan.
Purpose:
To report the case of a patient with refractory chronic eosinophilic pneumonia who developed rheumatoid arthritis during anti-interleukin (IL)-5 therapy.
Case Report:
The case of a 66-year-old male ex-smoker with allergic rhinitis who had dyspnea and chronic cough for 6 months and who was ultimately diagnosed with chronic eosinophilic pneumonia is reported. Long-term corticosteroid therapy was necessary due to recurrence of the chronic eosinophilic pneumonia during tapering of the corticosteroid. As a steroid sparing strategy, mepolizumab was initiated, and the steroid was tapered gradually. When the dose of prednisolone was 2 mg/day, he developed polyarthralgia. Mepolizumab was changed to benralizumab considering the possibility that arthralgia was a side effect of mepolizumab; however, the arthralgia continued and he was ultimately diagnosed with rheumatoid arthritis. Methotrexate was initiated and his arthritis improved. Thereafter, benralizumab was discontinued after 5 injections, and he subsequently required neither systemic corticosteroids nor biologics.
Conclusion:
The present case may suggest that suppression of IL-5 induces rheumatoid arthritis in certain patients; however, it is also possible that initial steroid therapy improved subclinical RA and made it remain undiagnosed, and the parallel OCS tapering during IL-5 therapy could have contributed to unveil the underlying RA. Further studies are required to establish guidelines on the optimum use of anti-IL-5 therapy and to understand the interactions between chronic eosinophilic pneumonia, anti-IL-5 therapy, tapering of corticosteroid and development of rheumatoid arthritis.
Insights
A patient with chronic eosinophilic pneumonia developed rheumatoid arthritis during anti-interleukin-5 therapy. This case suggests a potential link between IL-5 suppression and RA development, warranting further investigation.
Area of Science:
- Pulmonology
- Rheumatology
- Immunology
Background:
- Chronic eosinophilic pneumonia (CEP) is an inflammatory lung disease requiring long-term management.
- Refractory CEP cases often necessitate advanced therapies, including biologics.
- Interleukin-5 (IL-5) is a key cytokine in eosinophilic inflammation.
Observation:
- A 66-year-old male with allergic rhinitis and refractory CEP was treated with mepolizumab, an anti-IL-5 biologic.
- During gradual corticosteroid tapering, the patient developed polyarthralgia, leading to a diagnosis of rheumatoid arthritis (RA).
- Switching to benralizumab did not resolve arthralgia; however, methotrexate treatment improved RA symptoms.
Findings:
- The patient achieved steroid- and biologic-free remission of both CEP and RA after benralizumab discontinuation.
- This case highlights a potential association between IL-5 pathway inhibition and the manifestation of RA.
- The interplay between CEP, anti-IL-5 therapy, corticosteroid withdrawal, and RA development is complex.
Implications:
- IL-5 suppression might unmask or induce rheumatoid arthritis in susceptible individuals.
- Further research is needed to elucidate the mechanisms linking anti-IL-5 therapy to RA.
- Clinical guidelines may need to consider monitoring for RA development in patients receiving anti-IL-5 treatments for CEP.
Related Concept Videos
01:23Rheumatic Heart Disease I: Introduction
01:20Asthma: Pathogenesis and Management
Asthma is classified as allergic and non-allergic. Allergens such as dust mites, pollen, and pet dander trigger allergic asthma, while factors like cold air, intense emotions, or exercise can induce non-allergic asthma.
01:30Asthma-IV: Diagnostic and Management
Clinical Assessment for Asthma:
This is the first step in diagnosing and managing asthma. It includes:
01:26Asthma-II: Pathophysiology and Classification
Additionally, environmental and genetic factors play crucial roles in determining an individual's susceptibility to asthma and the severity of their condition.
Critical processes in asthma pathophysiology include:
01:20Chronic Obstructive Pulmonary Disease-II: Pathophysiology
Chronic Inflammation
01:24T Cell Types and Functions
Th1 cells stimulate dendritic cells to express necessary co-stimulatory molecules on their surfaces for...