Table 5.

Common microorganisms responsible for contact lens-related microbial keratitis

Common microorganisms associated with contact lens microbial keratitis
Bacteria (71%–88%)8,119
Gram-positive
Staphylococcus spp.11	20%
Coagulase-negative Staphylococci5,112,123	16.8%–49%
Staphylococcus aureus112	5.9%
Staphylococcus epidermidis119	4.8%
Gram-negative
Pseudomonas5,10,11,112,119,122,123	19%–73.5%
Serratia5,11,119,122	4.8%–23%
Fungal (2.6%–5%)6,8,10,119
Filamentous
Fusarium124	51%a–68%b
Aspergillus124	9.2%a–11%b
Yeast
Candida124	2%b–12%a
Acanthamoeba (0.9%–4%)8,119
Acanthamoeba castellanii125,126	38%–66%
Acanthamoeba polyphaga126	30%

Notes: The specific microbes that are in bold text indicate the most common species. Percentages do not add up to 100 as sterile keratitis cases can also be found.

^anon-Fusarium outbreak¹²⁴ (January 2001–September 2004 and October 2006–December 2007);

^bFusarium outbreak¹¹¹ (October 2004–September 2006).