Objective: To determine the importance of sinusitis as a cause of orbital cellulitis, the causative organisms and peak age of occurrence.

Material and Methods: A retrospective study of records of 50 patients hospitalized with orbital cellulitis (1-15 years) were reviewed and analysed in Prince Zeid Hospital 2004-2006. Radiographic sinus examinations and eye swabs performed prior to antibiotic treatment to all admitted patients.

Results: Sinusitis was evident in 69% of the patients. Eye swab cultures indicated 75% had streptococcal, staphylococcal ( yes ) . The most common causative organisms were Streptococcus viridans (50%) and Staphylococcus aureus (32%)and the peak age (of patients )is 1-4years.

Conclusion: Sinusitis is an important cause of orbital cellulitis

Keywords: sinusitis, orbital cellulitis.

Orbital cellulitis is commonly encountered by the ophthalmologist, with serious complications, such as optic nerve involvement that may lead to loss of vision, meningitis and brain abscess, requiring urgent intervention.

The patient is usually a child or young adult who presents with a relatively sudden onset of unilateral chemosis, pain, lid oedema, reduction of ocular movements and proptosis, most often laterally and downwards [1,2].

The infection usually spreads to the orbit from the nasopharynx or from the frontal, maxillary or ethmoidal sinuses[2]. The strong association between orbital cellulitis and sinusitis, and the difference in management that may be needed when sinusitis is present, makes it necessary to exclude the presence of sinusitis in all patients with orbital cellulitis [1].

So the objective is to determine the importance of sinusitis as a cause of orbital cellulitis, the causative organisms and peak age of occurrence.

A retrospective study of records of 50 patients hospitalized with orbital cellulitis (1-15 years) were reviewed and analysed in Prince Zeid Hospital 2004-2006. Radiographic sinus examinations and eye swabs were performed prior to antibiotic treatment to all admitted patients.

Prior to antibiotic treatment, all patients underwent complete ophthalmological and ear, nose and throat (ENT) evaluation, and eye swabs were taken for culturing. Complete blood count and sinus X-rays were performed for all patients.

Computerized tomography scans for sinuses were carried out on 10 patients to reveal the anatomy of the ethmoid and sphenoid sinuses because of age restriction, <2 yr.

The patients were treated with a wide range of antibiotics, the most commonly used being ampicillin, ceftriaxone, cephotaxim and prostaphyllin or vancomycine then modified according to culture results.

Surgical drainage of sinuses was carried out for one patient while still infectious. Four patients required drainage at a later stage.

Of the 50 patients in the study, 40 were under 4 years of age, 6 were aged between 4 years and 15 years and 4 were older than 15 years. Table 1.

36 patients (72%) had evidence of sinusitis. Of these, 22 patients (61%) had evidence of ethmoiditis, 6 (16%) had evidence of maxillary sinusitis and 8 (22%) had evidence of pansinusitis. A 2-year-old patient had recurrent orbital cellulitis additional to ethmoiditis.

The eye swab cultures showed 43 patients (86%) to be infected as follows: 25 (50%) patients with Streptococcus viridans,16 (32%) with Staphylococcus aureus and 2 (4%) with Enterococcus .
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A few patients were seen in the summer months but most others in winter. It was found that 65% of the patients were febrile; also 60% of the patients had neutrophilic leukocytosis, while in 40%, the complete blood count was considered normal.

Tabel 1 Age distribution of study patients

Table 2: Organism distribution of study patients

Orbital cellulitis is generally an infection of children and young adults. Patients on presentation usually have proptosis, anaesthesia of the area innervated by the ophthalmic and maxillary branches of the trigeminal nerve, impaired ocular rotations, ocular pain aggravated by ocular rotation, increased intraocular pressure, decreased visual acuity and afferent pupillary defect [2].

History of upper respiratory tract infection with or without nasal discharge may be present. ENT evaluation frequently shows nasal hyperaemia, swelling and pus issuing from the middle meatus. X-ray evidence of sinusitis is positive in 70% of adults where frontal, maxillary and ethmoidal sinuses show equal involvement, whereas the ethmoidal sinuses are most frequently involved in the paediatric age group [3].

Venous congestion and papilloedema indicate abscess formation, which may be detected by ultrasound and is usually a dangerous sign especially in the second decade of life [2]. The most common causative organisms reported are S. pneumoniae, Staph. aureus, S. pyogenes, and, in children under 5 years of age, Haemophilus influenzae [2,3].

Patients with orbital cellulitis should immediately be admitted to hospital. Management requires a complete and differential blood count, Gram stain and cultures of secretions from the conjunctiva, nasal cavity, abscesses, fistulas and from any lacerations. If meningeal signs are present a cerebrospinal fluid sample should be taken. Sinus X-rays should be obtained for all patients and if there is orbital involvement, a computerized tomography scan is indicated [4].

Initial treatment consists of appropriate intravenous antibiotics based on the result of the Gram stain as well as to cover the commonest organisms reported.5

A lack of response to antibiotics, decreasing vision, the presence of an orbital or subperiosteal abscess, and the need for diagnostic biopsy in atypical cases are indications for surgical intervention. Both the orbit and the infected sinuses should be drained [4].

1.Sinusitis is an important cause of orbital cellulitis, confirmed by radiographic studies or computerized tomography scans to assess the presence of sinusitis for all patients with orbital cellulitis.

2.Causative organisms mostly were S.viridans followed by Staph.aureus. Thus, initial antibiotics should fully cover both organisms.