Hospital-acquired sinusitis is a common cause of fever of unknown origin in orotracheally intubated critically ill patients

Sinus X-rays (SXRs) were performed in all patients with fever for which an initial screening (physical examination, microbiological cultures and chest X-ray) revealed no obvious cause. All patients were followed with a predefined protocol, including antral drainage in all patients with abnormal or equivocal results on their SXR.Initial screening revealed probable causes of fever in 153 of 351 patients (43.6%). SXRs were taken in the other 198 patients (56.4%); 129 had obvious or equivocal abnormalities. Sinus drainage revealed purulent material and positive cultures (predominantly Pseudomonas and Klebsiella species) in 84 patients. Final diagnosis for the cause of fever in all 351 patients based on X-ray results, microbiological cultures, and clinical response to sinus drainage indicated sinusitis as the sole cause of fever in 57 (16.2%) and as contributing factor in 48 (13.8%) patients with FUO. This will underestimate the actual incidence because SXR and drainage were not performed in all patients.Physicians treating critically ill patients should be aware of the high risk of sinusitis and take appropriate preventive measures, including the removal of nasogastric tubes in patients requiring long-term mechanical ventilation. Routine investigation of FUO should include computed tomography scan, SXR or sinus ultrasonography, and drainage should be performed if any abnormalities are found.A large proportion of patients admitted to the intensive care unit (ICU) are likely to develop fever of unknown origin (FUO) at some point of their stay there. Many of these episodes are due to well-recognised hospital-acquired infections such as ventilator-associated pneumonia (VAP) and central venous catheter infections [1,2]. Various diagnostic strategies have been developed to handle such infectious complications in the ICU, many of which have been laid down in hospital or national guidelines [3,4]. However, the potential role of sinusitis as a source of hospital-acquired infecti