The goal of treatment is the induction and maintenance of remission so as to prevent progression of fibrosis and organ destruction in affected organ(s). An international panel of experts have developed recommendations for the management of<unk> . They concluded that in all cases of symptomatic, active<unk>  that treatment is required. Some cases with asymptomatic<unk>  also require treatment, as some organs tend to not cause symptoms until the late stages of<unk> . Urgent treatment is advised with certain organ manifestations, such as aortitis, retroperitoneal fibrosis, proximal biliary strictures, tubulointerstitial nephritis, pachymeningitis, pancreatic enlargement and pericarditis. Induction of remission In untreated patients with active<unk> , the recommended first-line agent for induction of remission is glucocorticoids unless contraindications exist. Glucocorticoids characteristically result in a rapid and often dramatic improvement in clinical features and often a resolution of radiographic features. However, where advanced fibrotic lesions have resulted in irreversible damage, the response to glucocorticoids and other current treatment options may be poor or even absent. Although not validated yet in clinical trials, the common induction regime is prednisolone 30–40 mg per day for 2–4 weeks, then gradually tapered over 3 to 6 months. Recurrences during or after tapering of glucocorticoids are frequent, however. Steroid-sparing immunosuppressive agents might be considered, depending on local availability of these drugs, for use in combination with glucocorticoids from the start of treatment in order to reduce the side-effects of prolonged glucocorticoid usage. Steroid-sparing agents that have been used include rituximab, azathioprine, methotrexate, and cyclophosphamide, although trials are needed to ascertain the effectiveness of each drug in<unk> . Maintenance Following a successful induction of remission, maintenance therapy might be given in some cases, for example when there is a high risk of relapse or in patients with organ-threatening manifestations. Common maintenance therapy is prednisolone 2.5–5 mg per day, or use of a steroid-sparing agent instead. Relapse Relapses are common, and a previous history of relapse appears to be a strong predictor of future relapse. When relapse occurs while off therapy and there has been a prolonged<unk>  remission following initial glucocorticoid induction, then the relapse can usually be managed successfully with a re-induction strategy using glucocorticoids. Introducing a steroid-sparing agent might also need to be considered for relapses; however, none has been tested in prospective, controlled studies, and evidence for their efficacy beyond that offered by concomitant glucocorticoid therapy is scarce. In one retrospective cohort study, baseline concentrations of serum IgG4, IgE and blood eosinophils were found to be independently predictive of relapse risk following treatment with rituximab with or without glucocorticoids; the higher the baseline values, the greater the relapse risk and the shorter the time to relapse. Other interventions When organ involvement causes local mechanical problems, further organ-specific interventions may be necessary. For example, when a tumefactive lesion causes obstruction of the bile duct, it may be necessary to insert a biliary stent to allow the bile to drain freely. Similarly, ureteral or vascular stents, surgical resection or radiotherapy may be considered for various different presenting problems. Trials Research is also underway to evaluate the effect and safety of plasmablast-directed therapy with a monoclonal antibody (XmAb5871) which inhibits B-cell function without depleting these immune cells. XmAb5871 targets CD19 with its variable domain and has an Fc domain that has increased affinity to FcγRIIb.
IgG4-related disease
IgG4-related skin disease
Anti-IgLON5 disease
IgA vasculitis
Isolated primary immunoglobulin M deficiency
Antisynthetase syndrome
Undifferentiated connective tissue disease
Leukotriene receptor antagonist-associated Churg–Strauss syndrome