Acute sinusitis

Viral sinusitis is very common. Bacterial sinusitis should be suspected if symptoms persist for more than 7 days.

  • Symptoms - include nasal congestion, purulent nasal discharge, maxillary tooth discomfort, hyposmia or anosmia, cough, facial pain or pressure that is made worse by bending forward, headache, fever, and malaise.
  • Examination - nasal turbinate oedema, nasal crusts, purulence of the nasal cavity and posterior pharynx, and failure of transillumination of the maxillary sinuses.
  • Most viral infections improve in 7 to 10 days - persistence of symptoms suggests bacterial sinusitis
  • Symptoms of viral sinusitis, including fever, mimic those of bacterial sinusitis, although discolouration of nasal discharge may help differentiate.
  • Strep. pneumoniae and Haemophilus influenzae are the major bacterial pathogens in adults (Branhamella (Moraxella) catarrhalis in children).
  • Potential complications of include local extension (e.g. orbital cellulitis) and the spread of bacteria to the CNS / cavernous sinus
  • Clinical symptoms show poor sensitivity and specificity [Bandolier] (table below).
Comparison (with sinus puncture) No. of studies No. of patients Weighted prevalence (%, range) Positive likelihood ratio Negative likelihood ratio




57 (26-80)






56 (27-80



Clinical examination



46 (44-48)



  • Other reviews have shown that [positive predictive value,negative predictive value]
    • "Biphasic illness" is the most useful clinical clue (viral UTRI resolving then recurrence of unilateral symptoms)
    • Purulent discharge [62%,78%], Pain on bending fwd [78%,73%], maxillary toothache [59%,56%], pain with chewing [54%,53%] are poor predictors
  • Please note that allergic rhinitis is a rare initiating factor


CT maxilla sinusitisCT amxilla normal
  • Plain x-rays or CT have poor sensitivity(76%) and specificity (79%) and are NOT indicated
    • May demonstrate - sinus opacity, air–fluid level or marked mucosal thickening
    • But cannot differentiate viral from bacterial

Differential diagnosis


  • Advise adjunctive treatment in all.
  • Antibiotics can help relieve uncomplicated sinus infections, but they do not make a major difference on clinical cures [Cochrane review 2005]
  • If on balance you decide to use antibiotics, current CUH antibiotic guidelines suggest tetracycline for 10 days.

Adjunctive treatment

  • Diet (increase fluid intake), steam and local heat are advisable
  • No clinical trials have demonstrated any increased efficacy of topical steroids, topical decongestants, oral decongestants, antihistamines or mucolytic agents
  • Avoid topical decongestants for > 5/7 as will result in rebound symptoms.

Content by Dr Íomhar O' Sullivan 10/10/2005. Reviewed Dr ÍOS 12/01/2007. Last review Dr ÍOS 4/12/18.