The clinical utility of anti-ribosomal P autoantibodies in systemic lupus erythematosus

Abstract

Systemic lupus erythematosus (SLE) is a chronic inflammatory disease that can affect multiple organs and thus has a large spectrum of clinical presentations. Assessment of the autoantibody profile is fundamental for the clinical management of SLE patients, providing important data for diagnosis, clinical characterization and disease activity evaluation. Anti-ribosomal P protein (anti-Rib-P, anti-P) antibody, described in the 1980s, is a serological marker for SLE that is present in 13–20% of cases. This reactivity was initially thought to be associated with neuropsychiatric involvement in SLE, with certain conflicting results. Subsequently, associations of anti-Rib-P with liver and renal involvement in lupus were reported. Recently, anti-Rib-P was detected in autoimmune hepatitis patients. Anti-Rib-P reactivity to Trypanosoma cruzi ribosomal target antigens in patients with Chagas heart disease has also been described. This review focuses on the usefulness of the determination of anti-Rib-P in SLE and in other autoimmune and non-autoimmune disorders in clinical practice.

Keywords::

• anti-P
• anti-ribosomal P antibody
• anti-Rib-P
• autoantibodies
• lupus
• systemic lupus erythematosus

Acknowledgement

We thank Cleonice Bueno for providing the figure depicting IIF (antinuclear antibodies).

Financial & competing interests disclosure

This study was supported by grants from Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) 2011/10490-0 (to E Bonfa), Conselho Nacional de Desenvolvimento Científico e Tecnológico (301411/2009-3) (to E Bonfa) and Federico Foundation (to SG Pasoto and E Bonfa). The authors have no other relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript apart from those disclosed.

No writing assistance was utilized in the production of this manuscript.

Key issues

• Anti-ribosomal P protein (Anti-Rib-P) antibody is highly specific for systemic lupus erythematosus (SLE) and its evaluation may improve the accuracy of SLE diagnosis.

• The prevalence of anti-Rib-P varies widely between different ethnic groups, with a higher frequency observed in Asian SLE patients (36%) than in Caucasian or African American patients (15%).

• Anti-Rib-P is significantly associated with disease activity and may be useful for the follow-up of SLE patients, particularly with CNS and renal flares.

• Anti-Rib-P is more prevalent in juvenile-onset SLE than in adult-onset SLE.

• Anti-Rib-P may predict subsequent neuropsychiatric manifestations in SLE.

• Anti-Rib-P has been identified as a novel serological marker for membranous lupus nephritis, and this antibody may predict a better long-term renal outcome.

• Anti-Rib-P is associated with SLE-related hepatitis.

• Anti-Rib-P is detected in 10% of autoimmune hepatitis patients without SLE, and this antibody seems to predict a worse autoimmune hepatitis prognosis.

• Anti-Rib-P may identify a subgroup of overlap syndromes that is particularly associated with lupus.

• Anti-Rib-P reactivity in Chagas’ disease is an immune response to Trypanosoma cruzi, and not an autoimmune response.

Notes