Lacrimal gland function in autoimmune pancreatitis

Autoimmune pancreatitis (AIP) may be a pancreatic lesion of IgG4-related systemic disease. Lacrimal gland swelling is a rare extrapancreatic lesion of AIP. The aim of the present study was to investigate lacrimal gland function in AIP patients, and to determine changes after steroid therapy.

Schirmer's test and sialochemistry were done prospectively in 11 AIP patients. These tests were also performed after steroid therapy in 7 patients.

Dysfunction of tear secretion was found in at least one eye in 7 (64%) patients. The average lower level in both eyes was 4.3+/-1.5 mm in the 7 patients with lacrimal gland dysfunction, which was significantly lower than the 8.2+/-2.4 mm in patients with normal lacrimal gland function (p=0.005). There were no significant differences between the two groups in age at diagnosis of AIP, sex ratio, and the presence of swelling of the lacrimal glands and the salivary glands. Although there was no significant difference, mean serum IgG4 levels and mean salivary Na+ and beta2 microglobulin levels were lower in patients with normal lacrimal gland function. After steroid therapy, lacrimal gland function improved in 3 of 5 patients with impaired lacrimal gland function, though the degree of improvement was not marked compared to the improvement of salivary gland function.

Lacrimal gland function was frequently impaired in AIP patients, even when no lacrimal gland swelling was observed clinically. Lacrimal gland function impairment appears to be similar to impairment of salivary gland function in AIP patients.