Objective To investigate the characteristics and clinical significance of serum immunoglobulins in patients with Cronkhite-Canada syndrome (CCS).

Methods This retrospective study included CCS patients admitted to Peking Union Medical College Hospital from December 2009 to September 2024 who underwent serum immunoglobulin testing. Clinical manifestations and ancillary examination results were analyzed retrospectively.

Results Fifty-two patients were included (male: 3669.2%, female: 1630.8%), with median onset age of 60 (54-64) years and median diagnostic delay of 5 (3-12) months. Common manifestations included diarrhea (86.5%), abdominal pain (40.4%), hematochezia (19.2%), weight loss (86.5%), nail malnutrition (100.0%), pigmentation (88.5%), hair loss (84.6%), and hypogeusia (69.2%). Serum IgG reduction occurred in 21 patients (50.0%), while total IgE elevation was observed in 20(71.4%). Elevated serum IgG4 levels were noted in 11 patients (23.4%), with no significant clinical differences between IgG4-elevated and normal groups. IgG4 levels showed no statistical difference between active (n=43) and remission (n=27) groups. The hair loss rate was significantly higher in the total IgE-elevated group than that in the normal total IgE group (P=0.0383).

Conclusions CCS patients exhibit peripheral blood immunoglobulin disorders, with elevated IgE levels correlating with hair loss. This suggests an immune-mediated mechanism may underlie hair loss in CCS.