Demographic and clinical features of the study participants
A total of 550 adult patients were included in the study. The median (IQR 25-75) age was 53 (40-63.25) and the gender distribution was almost equal (male:52.9%). Hematology (27.7%) and nephrology (27.7%) were the most common clinical specialties where these patients were followed-up. The most common diagnosis was hypertension (49.2%) which was followed by chronic renal failure (33.5%), diabetes (24.1%), nephrotic syndrome (20.9%), multiple myeloma (19.4%) and renal transplantation (17.8%), respectively. Regarding the drug usage, corticosteroid (55.0%) and other immunosuppressive drugs (55.8%) were prominent compared to other treatments. The IgG value of 191 patients was lower than 600 mg/dL. Distribution of the clinics, patient diagnosis and concomitant treatment according to different IgG levels are shown in Table 1.