PT  - JOURNAL ARTICLE
AU  - Hsin-Yu Huang
AU  - Cheng-Lin Wu
AU  - Sheng-Hsiang Lin
AU  - Wei-Chen Lin
AU  - Fu-Chin Huang
AU  - Jia-Horung Hung
AU  - Sung-Huei Tseng
TI  - Microsporidial stromal keratitis: characterisation of clinical features, ultrastructural study by electron microscopy and efficacy of different surgical modalities
AID  - 10.1136/bjophthalmol-2019-315094
DP  - 2020 Nov 01
TA  - British Journal of Ophthalmology
PG  - 1613--1620
VI  - 104
IP  - 11
4099  - http://bjo.bmj.com/content/104/11/1613.short
4100  - http://bjo.bmj.com/content/104/11/1613.full
SO  - Br J Ophthalmol2020 Nov 01; 104
AB  - Aims To report the clinical manifestations, ultrastructure and evaluate the efficacy of therapeutic lamellar keratectomy (TLK) and penetrating keratoplasty (PK) for microsporidial stromal keratitis (MSK).Methods Fourteen MSK cases between 2009 and 2018 were recruited. Each patient’s clinical presentation, light microscopy, histopathology, PCR and electron microscopy (EM) of corneal samples were reviewed.Results The patients were 70.0±4.7 years old (average follow-up, 4.5 years). Time from symptoms to presentation was 10.6±13.0 weeks. The corneal manifestations were highly variable. Corneal scrapings revealed Gram stain positivity in 12 cases (85.7%) and modified Ziehl-Neelsen stain positivity in 9 (64.3%). Histopathology revealed spores in all specimens, while sequencing of small subunit rRNA-based PCR products identified Vittaforma corneae in 82% of patients. EM demonstrated various forms of microsporidial sporoplasm in corneal keratocytes. All patients were treated with topical antimicrobial agents or combined with oral antiparasitic medications for >3 weeks. As all patients were refractory to medical therapy, they ultimately underwent surgical intervention (TLK in 7, PK in 6 and 1 received TLK first, followed by PK). Postoperatively, the infection was resolved in 78.6% of the patients. Nevertheless, a high recurrence rate (21.4%) was noted during 3-year follow-up, with only two patients retained a final visual acuity ≥20/100.Conclusion MSK usually presents with a non-specific corneal infiltration refractory to antimicrobial therapy. The diagnosis relies on light microscopic examinations on corneal scrapings and histopathological analyses. Surgical intervention is warranted by limiting the infection; however, it was associated with an overall poor outcome.