Concurrent Microbial Keratitis and Nasolacrimal Duct Obstruction: Concordance, Etiopathogenesis, and Outcome

Abstract

Purpose: Nasolacrimal duct obstruction (NLDO) is believed to be a risk factor for microbial keratitis (MK). The primary objective of this study was to look at microbiological concordance between corneal scraping and lacrimal sac flora in patients with concurrent MK and NLDO. The secondary objective was to compare microbiological isolates from MK and NLDO, MK alone, NLDO alone, and healthy subjects. Methods: A prospective comparative study of 146 subjects with standard microbiological analyses was performed between February 2014 and October 2017. Results: Of the 146 subjects, 35 had concurrent MK and NLDO, 35 had MK, 41 had NLDO, and 35 were healthy subjects. Overall, mean age and sex distribution among groups were similar. In the MK and NLDO group, coagulase-negative staphylococci (CNS) were the most common isolates from the corneal scraping (n = 12/35, 34%) and lacrimal sac (n = 10/35, 29%) with 58% concordance. CNS were also the most common isolates from the NLDO group and healthy subjects, fungus being the most common isolate in the MK group. Anatomical success was achieved in 31 patients (89%) after dacryocystorhinostomy (DCR) in the MK and NLDO group. The difference between the number of patients who had successful DCR surgery but failure of medical therapy for MK (1/31) versus those who failed DCR and medical therapy for MK (3/4) was statistically significant (P = 0.002, Fisher exact test). Conclusions: CNS are the most common organisms in concurrent MK and NLDO (58% concordance), in patients with NLDO alone, and as commensals in healthy subjects. Persistence of NLDO may be responsible for a poorer outcome of MK in a concurrent setting.

Microbial Keratitis in Nepal: Predicting the Microbial Aetiology from Clinical Features

“…Although NLDO has been suggested as a major risk factor for non-healing bacterial keratitis (BK) [47], until recently few studies have confirmed an association between NLDO and BK [48,49]. Recent work from India adds weight to this by demonstrating that patients with untreated NLDO and MK have a worse clinical outcome [50]. For this reason, at our institution all patients with MK undergo lacrimal syringing.…”

Microbiological spectrum of microbial keratitis in patients presenting with nasolacrimal duct obstruction

“…There are only few studies regarding the spectrum of bacteria of chronic dacryocystitis, suggesting coagulase-negative Staphylococcus (CoNS) and Staphylococcus aureus, the most frequently isolated organisms in lacrimal sac infections. [6][7][8][9] The purpose of this study was to analyze the microbial spectrum of infectious keratitis in patients with co-existing nasolacrimal duct obstruction (NLDO). The pattern of antibiotic susceptibility of bacterial isolates was also studied.…”

Corneal ulcers with non-infectious appearance caused by nasolacrimal duct obstruction or canaliculitis

“…Previous report showed that coagulase-negative Staphylococci are the most common isolates from the nasolacrimal sac by conventional culture methods. 8 Other studies reported that in healthy subjects the microbiome in the nasolacrimal sac is usually dominated by Staphylococci and Corynebacterium . In contrast, a significantly lower relative abundance of Corynebacterium was observed in a case of NLDO.…”