Saprophytic sinusitis

Paranasal saprophytic aspergillosis is an uncommon cause of chronic or recurrent sinusitis. One series showed that 5% of 414 children treated for sinusitis had fungi only isolated and another 24% had bacteria and fungi isolated together (Laskownicka et al, 1978). In 600 adults treated for maxillary sinusitis, 14% revealed fungi, mostly A.fumigatus (Grigoriu et al, 1979). However most ear, nose and throat surgeons identify cases at surgery only every few years. The criteria for operation vary substantially and most patients with chronic sinusitis are not operated on. Most cases are in young to middle-aged adults.

It is likely that anatomical variation accounts for some cases (Stammberger, 1985). A common clinical finding is a bent middle turbinate with its convexity facing laterally instead of medially. Distortion of the osteomeatal complex, e.g. anatomical variation of the uncinate process will interfere with maxillary and frontal sinus drainage. Recurrent bacterial sinusitis leads to swelling of the ethmoidal air cells, further occluding the maxillary ostium. It is the combination of these factors that leads to most cases of paranasal saprophytic aspergillosis. In addition certain dental produces on the upper premolars and molars may introduce zinc oxide into the maxillary sinus which in turn creates favourable conditions for the growth of Aspergillus.

Usually discovered accidentally at surgery, prior symptoms are typical of chronic sinusitis; nasal congestion, facial discomfort or mild anterior headache, or post nasal dip. Most patients have previously received multiple courses of antibiotics, usually with at least a partial clinical response. Radiographs of the sinus demonstrate complete opacification of, usually, the maxillary sinus but occasionally of the sphenoid or rarely the frontal sinus. Usually only one sinus is involved radiologically and no bone erosion or extension of the soft tissue mass into adjacent structures. Endoscopic or CT examination of the nose usually demonstrates however, ethmoid involvement in addition to maxillary and/or sphenoid involvement (Stammberger, 1985).

Surgical aeration of the sinuses almost always cures the problem. Typically this is done via a Caldwell-Luc procedure and the sinus if found to contain a cheese-like, rubbery or friable soft tissue mass. The colour varies from green, brown to black and may be malodorous. The underlying mucosa is usually oedematous and may contain polyps. Most surgeons remove the mucosa and create a large antrostomy into the nose. Surgeons with extensive experience of the disease also maintain that the ipsilateral ethmoids should be explored and drained either endoscopically or surgically via a nasal approach (Stammberger, 1985). Relapse may occur otherwise. The role of nasal packing with amphotericin B or another antifungal agent is not established.

David W. Denning FRCP FRCPath FIDSA FMedSci
Professor of Medicine and Medical Mycology
Director, National Aspergillosis Centre
Education and Research Centre
University Hospital of South Manchester (Wythenshawe Hospital)
Southmoor Road
Manchester M23 9LT UK