**4. Risk factors**

The core components of the presentation of coinfections are risk factors. However, studies have not shown high causality for association. Coinfections have been diagnosed in patients with no reports of comorbidities (diabetes, immunosuppressive processes, etc.) although coinfec‐ tions can occur in patients with human immunodeficiency virus (HIV); however, this risk factor was not significant in the patients reported.

One risk factor for coinfection of fungus and bacteria is trauma. Dry eye also seems to be a risk factor.

The most frequently reported risk factor is the use of contact lenses, especially soft lenses. Coinfection with *Acanthamoeba* spp. *and Pseudomonas* spp. has been reported in contact lensassociated keratitis. Poor response to treatment has been observed in young people with greater frequency in women.
