Alpha-1 antitrypsin, a diagnostic and prognostic marker of vernal keratoconjunctivitis

A major chunk of ocular allergies in humans involve the conjunctiva, of which Vernal Keratoconjunctivitis (VKC) appears to be more common. VKC, a chronic allergic conjunctivitis, frequently affects young males and is characterized by intense inflammation of the limbal and/or tarsal conjunctiva. The etiology and immuno-pathogenesis of VKC still remain unclear. Alpha-1 antitrypsin (AAT), a member of serine proteinase inhibitor (SERPIN) superfamily, is an acute phase protein whose concentration in blood increases in response to inflammation. AAT deficiency is one of the many factors that may be involved in several abnormalities such as liver disease, emphysema, inflammatory joint diseases and inflammatory eye diseases. In the present study, the role played by this protein in VKC was analyzed in a selective case/control study to assess its diagnostic and prognostic value.

The case control study included 50 patients of VKC reporting to Ophthalmology out patient department (OPD). Age and sex matched 40 healthy subjects served as control. Serum AAT level of both the cases and controls were evaluated and compared. Moreover the serum AAT levels of the patients at presentation were compared with their serum AAT level after three weeks post treatment.

Levels of AAT in the serum of VKC patients at presentation (2.80 ± 0.42 mg/ml) were significantly higher as compared to controls (2.31 ± 0.21 mg/ml) whereas no significant difference was observed between the serum level of post treatment VKC patients (2.48 ± 0.26 mg/ml) and controls.

AAT is a potent acute phase protein whose concentration rises significantly in VKC, irrespective of the age and sex of the patient. Moreover, the serum level of AAT declined significantly post treatment; therefore it might be used as a prognostic marker.