Recurrent microbial keratitis in eyes with keratoconjunctivitis sicca with coexisting ocular surface pathology.

Sir/Madam,

The management of microbial keratitis (MK) in presence of keratoconjunctivitis sicca and other coexisting surface pathologies presents a formidable medical and surgical challenge. MK in such eyes is associated with poor outcomes.[123] Other variables with a significant association with poor outcomes are prior treatment with topical steroids,[4] a delay in seeking treatment and failure to use fortified antibiotics.[5]

We performed a retrospective review of all eyes with keratoconjunctivitis sicca (KCS) coexisting with other surface pathologies such as mucosal scarring, previous transplants and/or eyelid disorders, which had recurrent MK (>1 discrete episode) and who were under regular follow-ups. The patients were identified from the microbiology register over 3 years period. The notes were reviewed in detail to study the clinical and microbiological profile.

Ten eyes (10 patients) were identified [Figure 1]. Average time interval between 2 episodes of MK was 5 months. Seven subjects experienced a total of 2 episodes of MK, while three patients had 3 episodes. Table 1 shows the baseline characteristics and Table 2 shows the characteristics of the eye at the time of the latest episode of MK. All had dryness of ocular surface and a degree of neurotrophia due to various reasons [Table 1]. All eyes had at least one corneal transplant except patient 2 [Table 1]. Five eyes had sutures in-situ at the time of recurrent MK [Figure 1]. Before the latest episode of MK, all eyes underwent at least one tarsorrhaphy procedure except one (patient no. 8, Table 1) that underwent several lid procedures for cicatricial entropion. All patients were on preservative free topical medications. Six eyes had BCVA of ≤6/60 before any episode of MK compared to 7 following the latest episode due to residual scarring [Table 2]. (This concurs with Musch et al,[6] who demonstrated poor visual outcomes in eyes with previous surgery/pathology and MK at a higher risk for poor visual outcome). Six eyes grew normal commensals (Coagulase negative Staphylococcus, Staphylococcus epidermidis, Staphylococcus aureus) on culture during the previous and the latest episodes of MK and 2 had no growth at all episodes [Tables 1 and 2]. At the latest episode of MK, 9 had a BCL, 7 were using topical steroids, 7 were using topical lubricants, 4 had concurrent meibomian gland dysfunction and were taking oral Doxycycline, 8 had occluded eyelid puncti and 5 had sutures at the time of recurrent infection [Table 2 and Figure 1]. All patients on soft bandage contact lens (BCL) where using preservative free G. Chloramphinicol (Minims Chloramphinicol, Baush and Lomb, UK) 4 times a day. Additional tarsorraphies and eyelid procedures to correct residual exposure (blink lagophthalmos) led to prevention of recurrence of infection in all cases.

Figure 1

Montage of eyes in this study. (a) Traumatic lid loss and several eyelid procedures including medial and lateral tarsorraphy showing active microbial keratitis. (b) Keratoconjunctivitis sicca secondary torheumatoid arthritis, a corneal patch graft and active microbial keratitis. (c) Keratoconjunctivitis sicca secondary to icthyosis, tarsorraphies, corneal patch graft and active microbial keratitis. (d) Keratoconjunctivitis sicca secondary to rheumatoid arthritis, lateral tarsorraphy, corneal patch graft and active microbial keratitis (e) Cicatricial phemphigoid, previous corneal graft and active microbial keratitis (f) Patient 6 with atopy and history of herpetic keratitis, corneal graft with active keratitis (g) Corneal graft for PBK and active microbial keratitis. (h) Steven Johnson Syndrome and Graft Vs Host Disease with previous eyelid procedures showing active microbial keratitis.(i) Keratoconjunctivitis sicca secondary to rheumatoid arthritis, previous tarsorraphy and microbial keratitis with drug deposits.(j) Corneal graft for pseudophakic bullous keratopathy, keratoconjunctivitis siccas due to rheumatoid arthritis and active microbial keratitis

Table 1

Baseline characteristics of the patients in this study

Table 2

Characteristics of the eye at the time of final episode of microbial keratitis

Simple but important implications of this series are Use of even mild or low-dose topical steroid should be critically questioned in patient with KCS with coexisting surface pathology or any degree of corneal exposure in presence of corneal sutures, especially if they could be supplanted by other measures to reduce ocular surface inflammation, such as improved lid hygiene until the exposure is corrected surgically. All measures to promote corneal epithelial health and integrity, including topical lubricants and eyelid closure should be pursued aggressively. While soft BCL may prove useful in promoting epithelial healing and adhesion, they may also predispose to corneal infections by virtue of relative stasis of the tears and routine use of preservative free G Chloramphinicol with soft BCL does not eliminate the possibility of microbial keratitis. During episodes of active ocular surface inflammation, punctal occlusion should be discouraged until inflammation is controlled, to allow the drainage of tears with inflammatory cytokines.