Ligneous conjunctivitis mimicking preseptal cellulitis in a 3-month-old infant.

Background: Ligneous conjunctivitis is a very rare form of pseudomembranous conjunctivitis with few published cases in literature. We aim to describe the ocular findings and treatment in an infant with ligneous conjunctivitis resembling preseptal cellulitis on presentation.

Materials And Methods: Case report of a 3-month-old girl who was referred to a tertiary centre for ophthalmic assessment due to progressive eyelid oedema with no response to initiated topical and systemic antibiotics. Ethical approval has been achieved from the local ethics committee of the Ghent University Hospital and informed consent has been obtained from the parents of the child.

Results: Examination under general anaesthesia showed multiple, wood-like fibrinous pseudomembranes, originating from the conjunctiva, consistent with ligneous conjunctivitis. After careful removal of the coagulated exudate covering the cornea, a central corneal epithelial defect was evident without stromal infiltration. Histopathologic examination confirmed the predominance of fibrin within the pseudomembranes. Plasminogen activity was below the normal range. Genetic analysis did not identify a pathogenic variant in the PLG gene. The corneal epithelium re-epithelialised during the following days and the conjunctival lesions gradually subsided over the ensuing weeks whilst continuing heparin-containing artificial tears.

Conclusion: A high level of suspicion is warranted in atypical cases of preseptal cellulitis which show no response to antibiotic treatment. Particularly in young children, examination under general anesthesia is warranted to allow diagnosis of rare causes of secondary eyelid oedema. We report an infant with unilateral ligneous conjunctivitis who responded well to topical, commercially-available heparin-containing artificial tears treatment. This approach is an effective and easy first-line treatment option in this condition, particularly in milder phenotypes.