Retrospective single-centre analysis of IgG4-related disease patient population and treatment outcomes between 2007 and 2017

Objective The aim was to gain a better understanding of the prevalence, organ involvement, clinical characteristics and long-term outcomes of medical and surgical treatments of IgG4-related disease (IgG4-RD). Methods Query of the Cleveland Clinic pathology database for IgG4 plasma cell staining between 2007 and 2017 yielded 1481 results, of which 57 cases were identified as highly likely ( n  = 28; 49%) or probable ( n  = 29; 51%) IgG4-RD by histopathological criteria and IgG4 serum concentrations. Patient demographics, type of treatment and outcomes were retrieved from medical records. Patients were designated as being in remission if indicated in the chart and/or symptom- and objective finding-free for >6 months, relapsed if symptoms/findings recurred after remission, active if no remission was achieved during follow-up, and as unable to determine if the duration of follow-up was <60 days or they were lost to follow-up. Results Of all patients who met the IgG4 staining criteria ( n  = 119), half ( n  = 57) satisfied the IgG4-RD histopathological criteria; 63% were males, age 57.9 ± 14.8 years. The average follow-up was 2.7 ± 2.2 years. The pancreas was the most affected organ in our cohort (26.4%). Almost half of the patients (45.6%; n  = 26) were managed surgically, 21.1% ( n  = 12) medically, and 24.6% ( n  = 14) received both types of treatment. Medical treatment included prednisone (45.6%), MTX (5.3%), AZA (7%) and rituximab (8.8%). Remission was achieved by 77% of patients receiving surgical, 67% receiving medical and 72% receiving both treatments. Conclusion A histological diagnosis of IgG4-RD could be made in half of the patients who had IgG4 + plasma cells ≥10/high-power field or IgG4 + /IgG + ratio >40%. In our cohort, surgical treatment compared with medical treatment had a higher proportion of remission according to our outcome classification.