Laboratory tests including complete blood count (CBC, diff), erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), HLA B27, HLA B5, liver and kidney function tests, HIV and hepatitis serology, PPD test, peripheral blood smear and blood and urine culture for exclusion of endogenous endophthalmitis were performed. The gene discussed is CRP; the disease is hepatitis A virus infection.