Clinical Guide > Comorbidities and Complications > Sinusitis


January 2011

Chapter Contents


Sinusitis is defined as an inflammation involving the membrane lining of any sinus, and is a frequent finding in people with HIV infection. It occurs very commonly as part of a viral upper respiratory infection (URI), and usually is self-limited. Bacterial sinusitis usually occurs as a secondary complication of a viral URI, which causes decreased patency of the nasal ostia, decreased nasal ciliary action, and increased mucus production. Acute sinusitis is defined as lasting up to 4 weeks, whereas chronic sinusitis persists for at least 12 weeks.

HIV-infected patients are susceptible to sinusitis for a number of reasons related to their immunosuppression. Pathophysiologic mechanisms for this susceptibility may include proliferation of lymphatic tissue contributing to nasal obstruction, defects in B-cell and T-cell immunity owing to HIV, and defects in production of immunoglobulins, specifically IgE, resulting in an exaggerated allergic response in the nasal mucosa. As in the general population, the most common pathogens causing acute bacterial sinusitis are Streptococcus pneumoniae, Moraxella catarrhalis, and Haemophilus influenzae. However, HIV-infected patients have a greater incidence of sinusitis caused by Staphylococcus aureus and Pseudomonas aeruginosa. The bacterial causes of chronic sinusitis are not well defined, but may involve more polymicrobial and anaerobic infections. In patients with severe immunosuppression, particularly those with CD4 counts of ≤50 cells/µL, sinusitis may be caused by Aspergillus and other fungal pathogens.

S: Subjective

The patient may complain of facial pain, frontal or maxillary headache, postnasal drip, or fever.

Ask the patient about specific symptoms, the duration and progression of symptoms, and treatments attempted.

O: Objective

A: Assessment

A partial differential diagnosis includes the following:

P: Plan

Diagnostic Evaluation

Uncomplicated acute sinusitis usually is a clinical diagnosis. There are no symptoms, physical findings, or tests that reliably distinguish bacterial from viral sinusitis. Patients generally can be assumed to have bacterial sinusitis if symptoms do not resolve, or if they worsen, over the course of 7-10 days. Any patient with high fever or severe or unusual symptoms should be evaluated urgently for other causes of illness.

Imaging studies usually are not indicated for uncomplicated acute sinusitis. In patients with a poor response to empiric antibiotic therapy or worsening symptoms, and those with suspected chronic sinusitis, computed tomography (CT) scans of the paranasal sinuses are the best initial radiologic study. Standard X rays (sinus series) can detect cloudiness or air-fluid levels and will show mucosal thickening (a nonspecific finding in HIV-infected individuals).

Cultures of nasal aspirates are not useful for diagnosis, because nasal fluids do not accurately represent pathogens in the paranasal sinuses. Sinus aspirate cultures will give definitive diagnosis of a specific organism in the majority of cases; this may be considered in complicated cases. Definitive diagnosis of invasive fungal sinusitis requires tissue for culture.


Treatment is multimodal. For viral sinusitis, treatment is based on symptom suppression; for bacterial sinusitis, an antibiotic is added to other therapies:

If acute bacterial sinusitis is suspected, treat as above and add an antibiotic for a 10-14 day course of therapy:

For chronic sinusitis, administer multimodal treatments as listed above for 3-4 weeks. The value of antibiotics in chronic sinusitis is unclear; consider especially if a trial of antibiotics has not been undertaken.

If symptoms persist or worsen, refer patients to an otolaryngologist for further evaluation and treatment.

Potential ARV Interactions

Protease inhibitors (PIs), particularly ritonavir-boosted PIs, may increase serum glucocorticoid levels if used concurrently with nasal steroids. Fluticasone (Flonase) nasal spray should not be used with ritonavir-boosted PIs unless expected benefits outweigh possible risks, and should be avoided, if possible, in patients taking unboosted PIs. Budesonide (Rhinocort Aqua) nasal spray should be avoided with ritonavir-boosted PIs. Interactions between PIs and other nasal steroids have not been well studied.

Patient Education