IgG4-related disease: findings from a retrospective cohort in Colombia

IgG4-related disease (IgG4-RD) is a recently described fibroinflammatory disorder. The most common presentations include salivary and lacrimal gland hypertrophy, orbitary disease, autoimmune pancreatitis, retroperitoneal fibrosis, and tubulointerstitial nephritis. Lymphoplasmacytic infiltration, fibrosis, IgG4+ cell hyperplasia, and elevated IgG4 serum levels are the primary pathophysiological findings related to the disease. We describe for the first time the epidemiology and clinical manifestations in our country.

A descriptive study of patients from a retrospective cohort based on clinical records of adults with IgG4-RD treated between 2014 and 2021 in a high-complexity national center.

23,381 patients from 12 centers nationwide until December 2021 provided demographic data. We limited the search through ICD-10 coding: M358, M359, and M368, other specified systemic involvement of connective tissue; L948, other specified localized connective tissue disorders; D472, monoclonal gammopathy; K861, other chronic pancreatitis; H051, H059, and H063, chronic inflammatory disease of orbit; and C488, malignant neoplasm of overlapping sites of retroperitoneum and peritoneum. Thirty-three patients were identified with IgG4-RD based on comprehensive diagnostic criteria. A definitive diagnosis was obtained in 48.48% of patients, a probable diagnosis in 27.7%, and a possible diagnosis in 24.24%. A total of 21 patients were female, with a male/female (M/F) ratio of 1/1.75. The median age at diagnosis was 53.87 years (interquartile range of 27.06), the minimum age of diagnosis was 11.53 years, and the maximum was 79.18 years. Regarding clinical presentation at diagnosis, ocular/orbitary involvement was present in 16 patients (48.48%), followed by head and neck in 10 patients (30.30%), and biliary tract/gastrointestinal in 9 (27.27%). A single-organ compromise was identified in 15 patients (45.45%), and 18 patients (54.55%) had two or more organs affected, with lymphatic and ocular/orbitary being the most commonly reported.

Epidemiologic and demographic data on IgG4-RD in our country are similar to those in the world medical literature. The higher frequency of the disease in males above 65 years and females under 65 years suggests distinct pathophysiologic factors related to sex and age. This work has a limitation of subreports or misreports, which physicians can make when registering ICD-10 codes in clinical records. Nonetheless, it is the legal record in Colombia and requires an analysis like the one made in this study.