One of the most common infections of the eyelid and periorbital soft tissues is preseptal cellulitis that is characterized by acute eyelid erythema and edema (
1). Primary sources of infection can be local skin trauma, sinus infections or penetrating trauma, specifically those involving the ethmoid sinus (
2,
3). Most of the time, this kind of bacterial infection results from local spread of an adjacent sinusitis or dacryocystitis, from an external ocular infection, or following trauma to the eyelids (
4). Fever is typically observed, however conjunctival hyperemia is typically absent (
2). Preseptal cellulitis may progress to form subperiosteal and orbital abscesses and spread posterior to the septum. Cavernous sinus thrombosis or meningitis could be the result of infection in the orbit and spread posteriorly (
5). The most common organisms are
Staphylococcus aureus,
Staphylococcus epidermidis,
Streptococcus species, and anaerobes, which are reflecting the bacteria that usually cause upper respiratory tract infections and external eyelid infections (
3).
Pseudomonas aeruginosa,
Neisseria gonorrhoeae,
Treponema pallidum,
Mycobacterium tuberculosis,
Bacteroides species, and fungal infections are rare causative organisms (
6,
7).
During last decades, in 1985,
Haemophilus influenzae was the most common organism isolated in blood cultures before the introduction of the
Haemophilus influenzae type b (Hib) polysaccharide vaccine (
8,
9).
Various antibiotic regimens have been used for the treatment of preseptal cellulitis infection such as ampicillin, cefuroxime, ampicillin with sulbactam, ampicillin and nafcillin and ampicillin and chloramphenicol (
6).
Similar symptoms have been observed in patients with preseptal or orbital cellulitis, such as eye pain, periorbital swelling, and/or fever. Differentiation between the 2 infections is very important since the treatment for each is different. The aim of this study was to evaluate risk factors in patients with preseptal cellulitis admitted to two educational hospitals in Tehran, Iran.