Comparing nasal secretion eosinophil count with skin sensitivity test in allergic rhinitis in Ibadan, Nigeria.
OBJECTIVE
The aim of this prospective study was to assess the usefulness of nasal smear eosinophilia compared with a skin sensitivity test for the diagnosis of allergic rhinitis and to determine the degree of correlation between the tests.


METHODS
Fifty patients with a clinical history suggestive of nasal allergy and 20 controls were studied. A range of allergens were used for the skin sensitivity test in both groups. Nasal smears were examined by light microscopy.


RESULTS
A positive skin test reaction was demonstrated in 90% of the study population and 25% of the controls, whereas 76% of the patients and 15% of the controls demonstrated significant nasal smear eosinophilia. There was 66% correlation between the skin test and nasal eosinophilia, although this was not statistically significant (correlation coefficient -0.187 p = 0.193). This study does, however, demonstrate that both tests are sensitive for the diagnosis of allergic rhinitis, with sensitivities of 0.90 (95% CI 0.82-0.98) for the skin test and 0.76 (95% CI 0.64-0.88) for nasal eosinophilia.


CONCLUSIONS
Both the skin-prick test and the nasal smear eosinophilia showed correlation with the clinical history, although the skin-prick test was more sensitive. No statistically significant correlation was demonstrable between the two tests.
Takwoingi
Yohanna
Y
Department of Otolaryngology, Birmingham Heartlands Hospital, Birmingham, UK. takwoingi@aol.com
Akang
Effiong
E
Nwaorgu
George
G
Nwawolo
Clement
C
D000293:Adolescent; D000328:Adult; D016022:Case-Control Studies; D004802:Eosinophilia / Q000175:diagnosis* / Q000503:physiopathology; D005260:Female; D006801:Humans; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D009297:Nasal Mucosa / Q000166:cytology / Q000378:metabolism*; D009299:Nasal Provocation Tests / Q000379:methods; D009549:Nigeria; D011446:Prospective Studies; D012221:Rhinitis, Allergic, Perennial / Q000175:diagnosis*; D012882:Skin Tests / Q000379:methods