J Rheum Dis.  2019 Jul;26(3):186-190. 10.4078/jrd.2019.26.3.186.

Tocilizumab-induced Thrombocytopenia in Patients with Rheumatoid Arthritis

• Lee JS
• Oh JS
• Hong S
• Lee CK
• Yoo B
• Kim YG

• KMID: 2451510
• DOI: http://doi.org/10.4078/jrd.2019.26.3.186

Abstract

OBJECTIVE
Interlukin-6 (IL-6) increases platelet count during inflammation and may act in a manner similar to thrombopoietin. Tocilizumab is a monoclonal antibody of the IL-6 receptor and widely used in the treatment of rheumatoid arthritis (RA). Here, we evaluated the incidence of tocilizumab-induced thrombocytopenia and clinical factors associated with the development of thrombocytopenia.
METHODS
Patients with RA, who were treated with tocilizumab and had exposed to other biologics previously in a tertiary hospital between January 2014 and December 2017, were retrospectively evaluated. We compared occurrence of thrombocytopenia between tocilizumab and previous biologics. Furthermore, the factors associated with thrombocytopenia were analyzed using logistic regression analysis.
RESULTS
In total, 114 patients with RA were treated with tocilizumab for mean 90.5 weeks (interquartile range, 30.9~174.9). Thrombocytopenia was reported in 14 patients (12.3%) and it was higher rate compared with previous biologics. Most cases were grade 1 thrombocytopenia. Multivariate analysis showed that patient age (odds ratio [OR], 2.170; 95% confidence interval [CI], 1.118~4.211; p=0.022) and platelet count prior to treatment with tocilizumab (OR, 0.972; 95% CI, 0.954~0.990; p=0.002) were significantly associated with the development of thrombocytopenia.
CONCLUSION
Old age is risk factor for developing tocilizumab-induced thrombocytopenia and higher platelet count prior to treatment is associated with lowering risk of development of thrombocytopenia. However, thrombocytopenia was tolerable.

Keyword

Rheumatoid arthritis; Interleukin-6; Antibodies; Thrombocytopenia

MeSH Terms

Antibodies
Arthritis, Rheumatoid*
Biological Products
Humans
Incidence
Inflammation
Interleukin-6
Logistic Models
Multivariate Analysis
Platelet Count
Receptors, Interleukin-6
Retrospective Studies
Risk Factors
Tertiary Care Centers
Thrombocytopenia*
Thrombopoietin
Antibodies
Biological Products
Interleukin-6
Receptors, Interleukin-6
Thrombopoietin