Fax +41 61 306 12 34 E-Mail karger@karger.ch www.karger.com Original Paper Int Arch Allergy Immunol 2011;155:263–270 DOI: 10.1159/000320050 Differences and Similarities between Allergic and Nonallergic Rhinitis in a Large Sample of Adult Patients with Rhinitis Symptoms Gabriele Di Lorenzo   a Maria Luisa Pacor d Emanuele Amodio   c Maria Stefania Leto-Barone   a Simona La Piana   b Alberto D’Alcamo   a Vito Ditta   a, b Nicola Martinelli   d Danilo Di Bona   b a  Dipartimento di Medicina Interna e Specialistica DIMIS, Università degli Studi di Palermo, b  Dipartimento di Biopatologia e Metodologie Biomediche, Università degli Studi di Palermo, c  Dipartimento di Scienze per la Promozione della Salute G. D’Alessandro, Sezione di Igiene, Università degli Studi di Palermo, Palermo, d  Dipartimento di Medicina Clinica e Sperimentale, Università degli Studi di Verona, Verona, Italia struction and rhinorrhea. AR patients had more severe symp- toms and recurrent conjunctivitis, whereas NAR patients had slightly more frequent episodes of recurring headaches as well as olfactory dysfunction. PNIF, blood eosinophil counts and VAS of nasal symptoms were higher in patients with AR. In a final logistic regression model, 10 variables were statisti- cally different between AR and NAR: age [OR 0.97 (95% CI 0.96–0.98)], sneezing [OR 4.09 (95% CI 2.78–6.00)], nasal pru- ritus [OR 3.84 (95% CI 2.60–5.67)], mild symptoms [OR 0.21 (95% CI 0.09–0.49)], intermittent/severe nasal symptoms [OR 3.66 (95% CI 2.06–6.50)], VAS [OR 1.06 (95% CI 1.04–1.08)], clinical response to antihistamines [OR 22.59 (95% CI 13.79– 37.00)], conjunctivitis [OR 4.49 (95% CI 2.86–7.05)], PNIF [OR 1.01 (95% CI 1.00–1.01)] and nasal eosinophil counts [OR 1.14 (95% CI 1.10–1.18)]. Receiver operating characteristic analysis showed high predictive accuracy for a model including these variables independently of the diagnosis of AR/NAR (cutoff !0.74). Conclusions: We showed that the several clin- ical and laboratory parameters reported above may help to reinforce or exclude the diagnosis of AR obtained with skin prick test. Copyright © 2011 S. Karger AG, Basel Key Words Allergic rhinitis  Non allergic rhinitis  Skin prick test  Peak nasal inspiratory flow  Blood eosinophil  Nasal eosinophil  Visual analog scale  Receiver operating characteristic Abstract Background: Allergic rhinitis (AR) and nonallergic rhinitis (NAR) may present with different clinical and laboratory characteristics. Methods: A total of 1,511 consecutive pa- tients, aged 18–81 years, diagnosed with rhinitis, 56% fe- males and 44% males, underwent complete allergic evalua- tion including skin prick test, blood eosinophil counts, nasal eosinophil counts, peak nasal inspiratory flow (PNIF) mea- surement and evaluation of nasal symptoms using a visual analog scale (VAS). Results: A total of 1,107 patients (73%) had AR, whereas 404 (27%) had NAR. Patients with NAR were older and predominantly female. A higher nasal eosinophils count was associated with AR and a lack of clinical response to antihistamines. AR patients had more sneezing and nasal pruritus, whereas NAR was characterized mainly by nasal ob- Received: May 31, 2010 Accepted after revision: August 6, 2010 Published online: February 2, 2011 Correspondence to: Prof. Gabriele Di Lorenzo Dipartimento di Medicina Interna e Specialistica DIMIS Università degli Studi di Palermo Via del Vespro 141, IT–90127 Palermo (Italy) Tel. +39 091 655 2987, Fax +39 091 655 2936, E-Mail dilo601  @  unipa.it © 2011 S. Karger AG, Basel 1018–2438/11/1553–0263$38.00/0 Accessible online at: www.karger.com/iaa