Prognostic Utility of Whole-Genome Sequencing and Polymerase Chain Reaction Tests of Ocular Fluids in Postprocedural Endophthalmitis

Abstract

Purpose: To associate detection of potential pathogen DNA in endophthalmitis with clinical outcomes.

Design: Prospective cohort study.

Methods: Patients in whom endophthalmitis was diagnosed following an intraocular procedure were recruited. Clinical outcome data from baseline, week-1, month-1, and month-3 visits were collected. Intraocular biopsy samples were cultured by standard methods. Quantitative polymerase chain reaction (qPCR) was performed for specific pathogens and whole-genome sequencing (WGS).

Results: A total of 50 patients (mean age 72 years old; 52% male) were enrolled. Twenty-four cases were culture-positive and 26 were culture-negative. WGS identified the cultured organism in 76% of culture-positive cases and identified potential pathogens in 33% of culture-negative cases. Month-1 and -3 visual acuities did not vary by pathogen-positive versus pathogen-negative cases as detected by either culture or WGS. Visual outcomes of Staphylococcus epidermidis endophthalmitis were no different than those of pathogen-negative cases, whereas the patients infected with other pathogens showed worse outcome. Higher baseline bacterial DNA loads of bacteria other than those of S epidermidis detected by WGS were associated with worse month-1 and -3 visual acuity, whereas the S epidermidis loads did not appear to influence outcomes. Torque teno virus (TTV) and Merkel cell polyomavirus (MCV) were detected by qPCR in 49% and 19% of cases, respectively. Presence of TTV at presentation was associated with a higher rate of secondary pars plana vitrectomy (P = .009) and retinal detachment (P = .022).

Conclusions: The presence and higher load of bacteria other than S epidermidis detected by WGS or DNA from TTV by qPCR in ocular fluids is associated with worse outcomes in post-procedure endophthalmitis.