OCT 04, 2019
This systematic review describes the efficacy of conventional and biologic disease-modifying antirheumatic drugs (DMARDs) in IgG4-related orbital disease (IgG4-ROD).
Study design
The authors performed a systematic search of the literature for studies written in English, or with English translations, that focused on the role of DMARDS in the outcomes of patients with IgG4-ROD.
Outcomes
The search identified 35 studies and case reports/series describing 95 patients. The median age of the patients was 49 years (range 5 to 83) and 41% were female. Mean follow up was 36 months. Orbital involvement included the lacrimal glands (66%), soft tissue of the orbit (32%) and extraocular muscles (29%). Systemic associations include salivary glands (43%), lymph nodes (27%) and pancreas (20%). The success of conventional DMARDs varied between 36% and 75% in patients with IgG4-ROD, while rituximab was successful in the majority (93%) of patients.
Limitations
This is a review of the literature. It is very difficult to assure that all cases met the exact same diagnostic criteria of IgG4-ROD. With multiple different studies, the treatments are varied, making it difficult to compare the different treatment groups. In addition, there is likely a reporting bias as most of the included articles were "successful" case reports or case series. Ideally, a prospective, comparative, randomized study could be designed to compared the most effective treatments to confirm if rituximab is the superior agent.
Clinical significance
IgG4-ROD is an increasingly recognized cause of orbital inflammation. The finding of rituximab’s effectiveness in the treatment of this disease should encourage physicians to use this for induction or maintenance therapy. In addition, the success of rituximab indicates the involvement of the B cell system in the pathophysiology of IgG4-ROD.