Determination of cytomegalovirus IgG synthesis by the albumin correction in the aqueous humor of posner-schlossmann syndrome

Abstract

Objective: To evaluate the usefulness of albumin correction in determination of cytomegalovirus IgG in the aqueous humor of Posner-Schlossman syndrome (PSS) patients. Methods: Cases series studies. Forty-two patients (26 men and 16 women) who were diagnosed as PSS were enrolled from Oct. 2009 to Oct. 2015 at the Eye and ENT Hospital. During the same period, 20 patients with primary open-angle glaucoma (POAG) and 30 patients with bacterial endophthalmitis or retinal necrosis were enrolled as negative control group and inflammatory disease control group, respectively. Aqueous humor and serum samples were assayed to detect CMV IgG by enzyme-linked immunosorbent assay (ELISA), and albumin by scattering immunonephelometry. CMV DNA in aqueous humor was assayed by polymerase chain reaction (PCR). The ratio which was calculated as the (aqueous humor CMV IgG/serum CMV IgG)/(aqueous humor concentration of albumin/serum albumin concentration) over 0.6 was considered as intraocular antibody formation. Performance of differentiating control eyes from eyes with CMV-positive PSS was evaluated by the receiver operating characteristic curve. The ANOVA test, Mann-Whitney test and Chi-square test were performed to compare the differences among groups. Results: The detectable rate of CMV IgG antibody in the aqueous humor was 76.2%, 100.0% and 10.0% in PSS, inflammatory disease control and POAG groups, respectively. The levels of CMV IgG antibody in the PSS groups were significantly higher than that of POAG groups (Z=4.23, P<0.001).The positive rate corrected by the albumin was 71.4%, 3.3% and 0.0%.The corrected positive rate in PSS groups was significantly higher than that of the inflammatory disease control and POAG groups (χ(2)=30.38, P<0.01; χ(2)= 24.89, P<0.01), with a sensitivity of 75.0% and a specificity of 98.0%. The area under the curve for calibrated ratio was 0.942 (95%CI: 0.859 to 0.984) which was higher than that of CMV IgG (Z=6.19, P<0.001).The corrected positive rate of CMV IgG antibody (71.4%) was higher than that of CMV DNA (47.6%, χ(2)=4.003, P=0.045). Conclusions: CMV IgG antibody ratio which was corrected by aqueous humor and serum albumin could effectively improve aqueous antibody specificity in PSS patients. Furthermore, CMV IgG antibody ratio combined with PCR could improve the sensitivity of CMV detection. All of which help clarify the CMV infection in PSS in CMV DNA negative eyes. (Chin J Ophthalmol, 2017, 53: 104-108).