Orbital Cellulitis Medication

Prompt administration of appropriate antibiotics is key to successful treatment of orbital cellulitis. Most cases of orbital cellulitis result from ethmoid sinusitis; in such cases, the initial antibiotics are chosen based on the most likely sinus pathogens, primarily Streptococcus pneumoniae and other streptococci, S aureus, H influenzae, and non-spore–forming anaerobes.

Orbital cellulitis resulting from infection of the maxillary sinus secondary to dental infections can be caused by microorganisms indigenous to the mouth, including anaerobes, commonly Bacteroides species. Those cases stemming from dacryocystitis most commonly are caused by S aureus, S pneumoniae, Streptococcus pyogenes, and nontypeable H influenzae. Those spreading from infections of the soft tissues of the eyelids and face are due most commonly to staphylococci and S pyogenes. The initial antibiotic regimen can be modified if the response is inadequate or if the cultures dictate otherwise.

The occurrence of methicillin-resistant S aureus in orbital cellulitis is increasing, and empiric antimicrobial therapy should be directed against these organisms if they are prevalent in the community. Infection due to methicillin-resistant S aureus is best treated with vancomycin, cefotaxime, and clindamycin.

Fungal orbital cellulitis also occurs and is primarily due to Mucor and Aspergillus species. Fungal infection requires antifungals, such as amphotericin.

Corticosteroids may be helpful, but they should not be started until after any surgery is performed and until the patient has been on appropriate antibiotics for 2-3 days.

If secondary glaucoma develops secondary to orbital cellulitis, ocular antihypertensives should be instigated promptly. In cases of posttraumatic orbital cellulitis, tetanus prophylaxis should be given according to standard protocol.

Class Summary

Appropriate antibiotics may include nafcillin (for Staphylococcus or Streptococcus species), cefotaxime (for gram-negative organisms, nontypeable H influenzae, Moraxella, and resistant pneumococci), and metronidazole (for anaerobes). Ticarcillin-clavulanate would cover most gram-positive and gram-negative organisms and most anaerobes. Nafcillin in combination with ceftazidime is also appropriate, although chloramphenicol may be substituted for ceftazidime. Cefazolin can be used in place of nafcillin in cases of mild allergy to penicillin and vancomycin in cases of severe allergy to penicillin. Vancomycin, cefotaxime, clindamycin, and trimethoprim/sulfamethoxazole double-strength would be appropriate for susceptible penicillinase and nonpenicillinase-producing strains of methicillin-resistant S aureus.

Vancomycin (Vancocin)

Tricyclic glycopeptide antibiotic for intravenous administration. Indicated for the treatment of susceptible strains of methicillin-resistant (beta-lactam resistant) staphylococci in penicillin-allergic patients.

Clindamycin (Cleocin)

Inhibits bacterial protein synthesis at the bacterial ribosomal lever, binding with preference to the 50S ribosomal subunit and affects the peptide chain initiation process.

Cefotaxime (Claforan)

Semisynthetic broad-spectrum antibiotic for parenteral use. Effective against gram-positive aerobes, such as S aureus (does not cover methicillin-resistant strains), including penicillinase and non-penicillinase–producing strains, and S pyogenes, gram-negative aerobes (eg, H influenzae), and anaerobes (eg, Bacteroides species).

Nafcillin (Unipen)

Semisynthetic penicillin effective against a wide gram-positive spectrum, including Staphylococcus, pneumococci, and group A beta-hemolytic streptococci.

Ceftazidime (Fortaz, Ceptaz)

Semisynthetic, broad-spectrum, beta-lactam antibiotic for parenteral injection. Has broad spectrum of effectiveness against gram-negative aerobes, such as H influenzae, gram-positive aerobes, such as S aureus (including penicillinase and non-penicillinase–producing strains) and S pyogenes, and anaerobes, including Bacteroides species.

Chloramphenicol (Chloromycetin)

Exerts bacteriostatic effect on a wide range of gram-negative and gram-positive bacteria and is particularly effective against H influenzae.

Ticarcillin (Ticar)

Semisynthetic injectable penicillin that is bactericidal against both gram-positive and gram-negative organisms, including H influenzae, S aureus (non-penicillinase–producing), beta-hemolytic streptococci (group A), S pneumoniae, and anaerobic organisms, including Bacteroides and Clostridium species.

Cefazolin (Ancef, Kefzol, Zolicef)

Semisynthetic cephalosporin for IM or IV administration. Has bactericidal effect against S aureus (including penicillinase-producing strains), group A beta-hemolytic streptococci, and H influenzae.

Class Summary

Fungal orbital cellulitis is a potentially lethal condition, and the principal organisms involved, Mucor and Aspergillus, require the use of antifungals.

Amphotericin B deoxycholate (AmBisome)

Antifungal of choice in treatment of fungal orbital cellulitis. Administered IV and may be appropriately administered before laboratory confirmation of fungal infection in cases of severe infection.

Class Summary

Nasal decongestants may help open the sinus ostia and aid with drainage in cases of orbital cellulitis secondary to sinusitis.

Phenylephrine nasal (Neo-Synephrine)

Beneficial in the treatment of nasal congestion that may cause blockage of ostia of sinus, interfering with sinus drainage.

Oxymetazoline (Afrin, Sinarest, Allerest)

Applied directly to mucous membranes where stimulates alpha-adrenergic receptors and causes vasoconstriction. Decongestion occurs without drastic changes in blood pressure, vascular redistribution, or cardiac stimulation.

Class Summary

These agents reduce IOP.

Acetazolamide (Diamox)

Inhibits enzyme carbonic anhydrase, reducing rate of aqueous humor formation, which, in turn, reduces IOP. Used for adjunctive treatment of chronic simple (open-angle) glaucoma and secondary glaucoma and preoperatively in acute angle-closure glaucoma when delay of surgery desired to lower IOP.