Rapid diagnosis of bacterial sinusitis using a simple test of nasal secretions

Diagnosis of sinusitis is often made based on history and physical exam. Sinus films or CT scans are helpful but expensive.


Nose and nasal cavities. Image source: Wikipedia, public domain.



Left-sided maxillar sinusitis (absence of the air transparency of left maxillar sinus). Image source: Wikipedia, public domain.

The authors studied whether analysis of 4 four easily measured substances in nasal secretions could predict bacterial sinusitis:

1. protein
2. pH
3. leukocyte esterase
4. nitrite

Those 4 substances are the same ones tested by the urine dipstick used to diagnose UTI.

A scoring system was developed to compute the results of the 4 assays in a single clinical score.

All patients with scores of 0 or 1 were CT or x-ray negative for bacterial sinusitis. All patients with scores higher than 4 were imaging study positive.

The authors concluded that combining 4 simple assays on nasal secretion can rule in or rule out bacterial sinusitis in 90% of patients.

Twitter comments: the tweets below are part of the series Medical Geek Humor on Twitter:

AllergyNotes Diagnosis of bacterial sinusitis (>90%) using a test of nasal secretions (4 = protein, pH, leuk esterase, nitrite) http://tinyurl.com/aqe6vy 21 minutes ago from TweetDeck

grahamwalker @AllergyNotes Re: bact sinusitis: Hmm. Can you just use a urine dipstick then? 9 minutes ago from web in reply to AllergyNotes

AllergyNotes @grahamwalker: "Re: bact sinusitis: Hmm. Can you just use a urine dipstick then?" - I don't think investigators looked at it from that point. You should email them. Full text is subscription only. 5 minutes ago from TweetDeck in reply to grahamwalker

A typical medical urinalysis (UA) usually includes:

- pH - normally 4.8 to 7.5.
- protein - normally negative (absent)
- nitrites
- leukocyte esterase


UA shows gross hematuria and bacteria. Image source: ClinicalCases.org.

References:
Rapid diagnosis of bacterial sinusitis in patients using a simple test of nasal secretions. Huang, Shih-Wen; Small, Parker A. Allergy and Asthma Proceedings, Volume 29, Number 6, November/December 2008 , pp. 640-643(4)
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