ACUTE AND CHRONIC BACTERIAL RHINOSINUSITIS


The tendency to suffer from rhinosinusitis is increased by a
variety of anatomical and physiological abnormalities. The
sinuses are normally kept infection free by continuous
movement of a mucus blanket over the respiratory
epithelium of the sinuses, through the sinus ostia, and into
the nasal cavity. Therefore, any factor that interrupts this
process increases the chances of infection.
The following anatomical features have all been
implicated in sinus disease, but their relative importance is
the subject of debate: septal deviation, bulla
ethmoidalis, concha bullosa, a prominent
uncinate process, and a narrow frontal recess. Nasal polyps
and other nasal disease processes may also block the sinus
ostia. Conditions which affect the mucociliary transport
mechanism such as allergic rhinitis, nasal polyposis, cystic
fibrosis, primary ciliary dyskinesia, and Kartagener’s or
Young’s syndromes will also be detrimental. Failure of the
mucociliary clearance from the sinuses through the ostia
leads to stasis and the formation of pus in the sinus.
In about 60% of cases, an acute bacterial rhinosinusitis is
caused by Streptococcus pneumoniae and Haemophilus
influenzae. The rest are caused by Streptococcus group A,
Streptococcus milleri, Staphlococcus aureus, Neisseria spp.,
gram-negative bacilli, Klebsiella sp., Moraxella catarrhalis,
and Pseudomonas sp. Anaerobic pathogens such as
Peptostreptococcus, Bacteroides spp., and Fusobacteria are
found in cases of maxillary sinusitis when the infection is
secondary to dental disease.
In principle, a bacterial sinusitis is a secondary infection
of a primary viral sinusitis. The symptoms will, therefore,
initially be those of a coryza but the patient will then develop
facial pain. The pain is characteristically dull, throbbing,
and worse on bending forward. Maxillary sinus pain tends to
be felt in the cheek but radiates down into the teeth. Frontoethmoid
disease gives pain around, behind, and between the
eyes. Isolated sphenoid sinusitis is rare but the pain may be
retro-orbital or felt on the vertex.
On examination there may be tenderness medially over
the maxillary sinus or above the inner canthus of the eye
over the fronto-nasal duct region. Swelling of the face is not
seen in uncomplicated sinusitis. Swelling over the cheek is
usually indicative of an underlying dental infection. The
maxillary sinus may be clear of infection or may be
secondarily infected. The typical endoscopic finding is pus
in the middle meatus (5.18). The diagnosis is made from the
history and examination findings but a CT scan of the
paranasal sinuses in coronal sequence will show partial or
total opacification of the affected sinuses.
Treatment of acute sinusitis is the subject of much debate
in the primary care setting. Supportive treatments with
analgesia and decongestants such as pseudo-ephidrine and
xylometazoline are logical. The role of antibiotics is
disputed, and there are understandable concerns about the
over-prescription of these agents. Several large studies
conducted in the primary care setting suggest that they are
of no value, but the entry criteria for some of these studies
were lax and it may be that many cases of viral coryza were
included, thus diluting any positive benefit for those subjects
with true bacterial sinusitis. Studies conducted in the
secondary care setting tend to be more supportive of the
value of antibiotics. These studies tend to have the
advantage of radiological confirmation of the diagnosis and,
therefore, have slightly different entry criteria. Most
otolaryngologists would recommend the use of antibiotics in
clear cases of bacterial sinusitis with toxaemia. In
community acquired sinusitis, a 2 week course of
amoxycillin should control the infection. Erythromycin or
one of the other macrolide antibiotics is useful in penicillin
allergic individuals.
Chronic rhinosinusitis may have an underlying
degree of inflammatory rhinitis that is helped by the
addition of topical steroid preparations. In
addition, recent studies suggest that prolonged
courses of low-dose or full-dose clarithromycin
(which has an anti-inflammatory as well as
antimicrobial action) may be of benefit. Refractory
cases will need endoscopic sinus surgery to enlarge
the natural sinus ostia to enhance drainage and
restore normal mucociliary clearance.

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