Background: Rheumatoid arthritis (RA) is a systemic autoimmune disease that primarily affects the joints but can also lead to extra-articular complications, including renal involvement.

Objectives: This study aims to evaluate the frequency, underlying mechanisms, and clinical consequences of renal involvement in patients with RA.

Methods: This is a cross-sectional and descriptive study including 100 patients suffering from rheumatoid arthritis, conducted over 11 months from February 2024 to December 2024. All patients underwent measurement of blood creatinine levels, creatinine clearance, Addis count, proteinuria screening, urine culture, and ultrasound.

Results: The study involved 100 patients, with an average age of 50 years and a female predominance (sex ratio 3:1). The median duration of the disease was 10 years. Ninety percent of patients were seropositive erosive, and 10% were seronegative erosive. All patients were treated with methotrexate after the diagnosis, 90% used NSAIDs, 60% were on corticosteroids with a daily dose of 10mg, and the average DAS28 CRP value was 3. Renal involvement was observed in 22% of cases (n = 22).The etiologies included: Urinary tract infection in 18% of cases (n = 4) with microscopic hematuria in 1 case and leukocyturia in 4 cases, as shown by urine culture. Renal tumor in 4.5% of cases (n = 1). Polycystic kidney disease in 4.5% of cases (n = 1) with hypertension. Drug-induced nephropathy (NSAIDs) in 18% of cases (n = 4).Associated autoimmune disease: Sjögren’s syndrome in 4.5% of cases (n =1). Renal amyloidosis in 4.5% of cases (n = 1).Fifteen patients (68%) had acute or chronic renal failure, 7 patients (31.8%) had proteinuria, and 14 patients (63%) had hypertension. However, only 3 patients developed nephrotic syndrome, with acute renal failure, proteinuria, and hypertension, along with lower limb edema in 2 patients. Renal biopsy was performed on these 3 patients (13.6%), revealing amyloid deposits, membranous glomerulonephritis (MGN), and segmental and focal hyalinosis (HF). The Addis count showed hematuria with leukocyturia in 7 cases and the presence of urinary casts in the case of MGN. Ultrasound showed renal atrophy in 3 patients (13.6%) with chronic renal failure. One case (4.5%) of chronic interstitial nephropathy was incidentally diagnosed by abdominal and pelvic CT. Therapeutic management: NSAIDs were discontinued in 81.8% of cases (18 patients). Methotrexate was discontinued in 22.7% of cases (5 patients), and biological therapy was recommended.

Conclusion: Renal involvement in rheumatoid arthritis is relatively common and can lead to significant clinical consequences. Therefore, regular monitoring of renal function in these patients is essential.

REFERENCES: NIL.

Acknowledgements: NIL.

Disclosure of Interests: None declared.

© The Authors 2025. This abstract is an open access article published in Annals of Rheumatic Diseases under the CC BY-NC-ND license ( http://creativecommons.org/licenses/by-nc-nd/4.0/ ). Neither EULAR nor the publisher make any representation as to the accuracy of the content. The authors are solely responsible for the content in their abstract including accuracy of the facts, statements, results, conclusion, citing resources etc.