**3. Etiology**

Preseptal cellulitis, as an eyelid infection, may be caused by inoculation following a trauma or skin infection, from spread of sinuses infection, upper respiratory tract infection, and any infection elsewhere disseminated through the blood.

Also, insect (spider) or animal bites, or a chalazion may be followed by eyelid infection[6].

Nearly two thirds of the cases of cellulitis are reported to be associated with upper respirato‐ ry tract infections, with one half of these from sinusitis. The most common microorganisms are Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus species, and anae‐ robes, known organisms that commonly cause upper respiratory tract infections and exter‐ nal eyelid infections[6]. Cold weather and upper respiratory tract infections are sometimes correlated with increased frequency of sinusitis, resulting in orbital cellulitis having seasonal peaks from late fall to early spring [7, 8].

Streptococcus pneumonia predominates when infection arises from sinuses infection, whereas Staphylococcus aureus and Streptococcus pyogenes often accompany local trauma and may be the most important pathology related toperiocular infection in a developing country.

Haemophilusinfluenzae B is now less common and usually occurs following bacteremic spread from a primary focus such as otitis media or pneumonia. Affected patients may have other foci of bacteremic spread including the meninges[9].

Haemophilusinfluenzae was the most common organism isolated in blood cultures before introduction of the vaccine, resulting with positive blood cultures during upper respiratory tract infections and in subcutaneous aspirates in nearly half of the patients with eyelid trau‐ ma or external ocular infections[10].

It has also been reported that total cases per year from all pathogens after the introduction of the Haemophilusinfluenzae vaccine declined as well, suggesting that Haemophilusinfluen‐ zae may have played a facilitative role in the pathogenesis of cellulitis[10].

Periorbital cellulitis has also been reported with smallpox and anthrax[6].

Frequent causes of preseptal cellulitis include Acinetobacter species, Nocardiabrasiliensis, Bacillus anthracis, Pseudomonas aeruginosa, Neisseria gonorrhoeae, Proteus spp, Pasteurel‐ lamultocida, Mycobacterium tuberculosis, and Trichophytonspp (the cause of "ringworm"). These pathogens can usually be linked to specific exposures[11-20].

Polymicrobial infections are also common[21, 22, 23].

managed medically, whereas orbital cellulitis requires an aggressive treatment and may re‐ quire surgical intervention [3, 4, 5]. Orbital cellulitis is a serious infection, especially in chil‐ dren, and may result in significant complications including blindness, cavernous sinus

The correct treatment of the preseptal cellulitis during the antibiotic era makes these compli‐ cations rare but the correct diagnosis and early treatment are important to prevent the life

Preseptal cellulitis, as an eyelid infection, may be caused by inoculation following a trauma or skin infection, from spread of sinuses infection, upper respiratory tract infection, and any

Also, insect (spider) or animal bites, or a chalazion may be followed by eyelid infection[6].

Nearly two thirds of the cases of cellulitis are reported to be associated with upper respirato‐ ry tract infections, with one half of these from sinusitis. The most common microorganisms are Staphylococcus aureus, Staphylococcus epidermidis, Streptococcus species, and anae‐ robes, known organisms that commonly cause upper respiratory tract infections and exter‐ nal eyelid infections[6]. Cold weather and upper respiratory tract infections are sometimes correlated with increased frequency of sinusitis, resulting in orbital cellulitis having seasonal

Streptococcus pneumonia predominates when infection arises from sinuses infection, whereas Staphylococcus aureus and Streptococcus pyogenes often accompany local trauma and may be the most important pathology related toperiocular infection in a developing

Haemophilusinfluenzae B is now less common and usually occurs following bacteremic spread from a primary focus such as otitis media or pneumonia. Affected patients may have

Haemophilusinfluenzae was the most common organism isolated in blood cultures before introduction of the vaccine, resulting with positive blood cultures during upper respiratory tract infections and in subcutaneous aspirates in nearly half of the patients with eyelid trau‐

It has also been reported that total cases per year from all pathogens after the introduction of the Haemophilusinfluenzae vaccine declined as well, suggesting that Haemophilusinfluen‐

zae may have played a facilitative role in the pathogenesis of cellulitis[10].

Periorbital cellulitis has also been reported with smallpox and anthrax[6].

thrombosis, meningitis, subdural empyema, and brain abscess.

infection elsewhere disseminated through the blood.

other foci of bacteremic spread including the meninges[9].

peaks from late fall to early spring [7, 8].

ma or external ocular infections[10].

threatening complications [4,5].

**3. Etiology**

108 Common Eye Infections

country.

Decreased immune function, as a side effect after the overuse of antibiotics, penetrating inju‐ ries, and diabetes mellitus, are all the factors that favor fungal infections such are aspergillo‐ sis or mucormycosis.


\* Modified from Devrimİ, Kanra G, Kara A, Cengiz AB, Orhan M, Ceyhan M, Seçmeer G. Preseptal and orbi‐ tal cellulitis: 15-year experience with sulbactam ampicillin treatment. Turk J Pediatr 2008; 50: 214-218.

**Table 1.** Common risk factors for preseptal cellulitis and orbital cellulitis


\* Modified from Devrimİ, Kanra G, Kara A, Cengiz AB, Orhan M, Ceyhan M, Seçmeer G. Preseptal and orbi‐ tal cellulitis: 15-year experience with sulbactam ampicillin treatment. Turk J Pediatr 2008; 50: 214-218.

**Table 2.** Common focal lesions on the face or near the orbita as the risk factors for preseptal cellulitis and orbital cellulitis\*


\* Pus and swab cultures from secretion of conjunctiva

\*\* Other than pneumococci

\*\*\* Modified from Devrimİ, Kanra G, Kara A, CengizAB, Orhan M, Ceyhan M, Seçmeer G. Preseptal and or‐ bital cellulitis: 15-year experience with sulbactam ampicillin treatment. Turk J Pediatr 2008; 50: 214-218.

**Table 3.** Common isolated\* microorganisms in cases with orbital and preseptal cellulitis\*\*\*

The causes of preseptal cellulites are classified as:


**Figure 1.** Pathophysiology of preseptal cellulitis

#### Risk factors [24, 25]

**Isolated agent Percentage**

\*\*\* Modified from Devrimİ, Kanra G, Kara A, CengizAB, Orhan M, Ceyhan M, Seçmeer G. Preseptal and or‐ bital cellulitis: 15-year experience with sulbactam ampicillin treatment. Turk J Pediatr 2008; 50: 214-218.

**•** extension from periorbital structures (paranasal sinuses, dental infection, intracranial)

Staphylococcus aureus 43% Coagulase-negative staphylococcus 26.6% Streptococcus pneumoniae 10% Haemophylusinfluenzae type B 6.6% Streptococcus\*\* 6.6% Klebsiellapneumonia 3.3% Pseudomonas aeruginosa 3.3%

**Table 3.** Common isolated\* microorganisms in cases with orbital and preseptal cellulitis\*\*\*

\* Pus and swab cultures from secretion of conjunctiva

The causes of preseptal cellulites are classified as:

**•** intraorbital (endophtalmitis, dacryoadenitis).

\*\* Other than pneumococci

110 Common Eye Infections

**•** exogenous (trauma, postsurgical)

**Figure 1.** Pathophysiology of preseptal cellulitis

**•** endogenous (bacteremia)

	- **•** Hordeola
	- **•** Chalazia
	- **•** Bug bites
	- **•** Trauma-related lesions
	- **•** Lesions caused by a recent surgical procedure near the eyelids
	- **•** Lesions caused by oral procedures
	- **•** Varicella
	- **•** Asthma
	- **•** Nasal polyposis
	- **•** Neutropenia
