Biologic therapy for amyloid A amyloidosis secondary to rheumatoid arthritis treated with interleukin 6 therapy: Case report and review of literature

Secondary Amyloidosis Treated with Tocilizumab as a Complication of Temporal Arteritis

Background

Temporal arteritis is a large-vessel vasculitis mostly seen in the elderly. Amyloidosis may be secondary to a chronic inflammation of body organs. Here, we present the second case report of temporal arteritis complicated by amyloidosis that was successfully treated by tocilizumab.

Case presentation

A 64-year-old female presented complaining of fatigue, fever, and diarrhea accompanied by abdominal pain. One year before presentation, she was diagnosed with temporal arteritis. She was treated with 15 mg/day oral prednisone for the last 6 months, with partial remission, but persistence of the fatigue and an elevated erythrocyte sedimentation rate (ESR, 56 mm/h). Physical examination showed tenderness of both temporal arteries and a soft abdomen. Colon tissue biopsy showed amyloid depositions in the vessels and stroma that were positive for Congo red staining. Tocilizumab was started with 8 mg/kg intravenous, the diarrhea resolved, and the arthralgia improved within 1 month, with a decrease in the ESR to 8 mm/h, and a C-reactive protein (CRP) level of 0.98 mg/dl. Monthly tocilizumab therapy remains efficacious 12 months later and was stopped due to lack of tocilizumab from the hospital. No side effects of tocilizumab were registered.

Conclusion

Chronic inflammation may be complicated by amyloidosis in patients with rheumatic diseases and genetic predisposition. Therefore, it is important to screen for intestinal Amyloid A (AA) amyloidosis in individuals with gastrointestinal disorders complicated by rheumatic disorders. AA amyloidosis may be complicated by temporal arteritis and presented with gastrointestinal symptoms such as diarrhea.

LEARNING POINTS

Amyloidosis is manifested by the deposition of insoluble protein aggregates in organs.Amyloid A (AA) amyloidosis occurs as a complication of chronic inflammation in patients with a genetic predisposition to rheumatic diseases.Temporal arteritis complicated with AA amyloidosis is extremely rare.

The prospects of interleukin-6 inhibition in rheumatoid arthritis: Olokizumab (novel monoclonal antibodies to IL-6)

Rheumatoid arthritis (RA) is a chronic immune-mediated rheumatic diseases (IMRDs) manifested with progressive destruction of joints, systemic inflammation of visceral organs and a wide range of co-morbidities associated with chronic inflammation. Among the cytokines involved in the pathogenesis of RA and certain other IMRDs, the role of interleukin (IL) 6 is of special interest. The introduction of mAbs tocilizumab (TCZ) and later sarilumab (SAR), both blocking the receptor of this cytokine, into clinical practice was an important achievement in the treatment of IIRDs at the beginning of the 21st century. As a novel approach in the treatment of RA, the humanized mAb against IL-6 olokizumab (OKZ) is in development by the Russian company R-PHARM under the license agreement with UCB Pharma. The review examines new data on efficacy and safety of OKZ in RA and the prospects of its use in rheumatology

SIG-1451, a Novel, Non-Steroidal Anti-Inflammatory Compound, Attenuates Light-Induced Photoreceptor Degeneration by Affecting the Inflammatory Process

Age-related macular degeneration is a progressive retinal disease that is associated with factors such as oxidative stress and inflammation. In this study, we evaluated the protective effects of SIG-1451, a non-steroidal anti-inflammatory compound developed for treating atopic dermatitis and known to inhibit Toll-like receptor 4, in light-induced photoreceptor degeneration. SIG-1451 was intraperitoneally injected into rats once per day before exposure to 1000 lx light for 24 h; one day later, optical coherence tomography showed a decrease in retinal thickness, and electroretinogram (ERG) amplitude was also found to have decreased 3 d after light exposure. Moreover, SIG-1451 partially protected against this decrease in retinal thickness and increase in ERG amplitude. One day after light exposure, upregulation of inflammatory response-related genes was observed, and SIG-1451 was found to inhibit this upregulation. Iba-1, a microglial marker, was suppressed in SIG-1451-injected rats. To investigate the molecular mechanism underlying these effects, we used lipopolysaccharide (LPS)-stimulated rat immortalised Müller cells. The upregulation of C-C motif chemokine 2 by LPS stimulation was significantly inhibited by SIG-1451 treatment, and Western blot analysis revealed a decrease in phosphorylated I-κB levels. These results indicate that SIG-1451 indirectly protects photoreceptor cells by attenuating light damage progression, by affecting the inflammatory responses.