Utilidad de la provocación nasal alérgeno específica valorada mediante rinometría acústica en niños polisensibilizados con rinitis alérgica

Abstract

OBJECTIVES: Primary objective: 1- To verify if results of the nasal provocation assessed by acoustic rhinometry are equivalent to those obtained by skin tests and specific IgE determination in vitro, in polysensitized patients. Secondary objectives: 1- Check if there is any cut point in the size of cutaneous papule or specific IgE that predict the result of the nasal provocation test. 2- Estimate the time consumption involved in performing the allergen-specific nasal provocation test in ordinary practice. 3- Assess the safety of the nasal provocation test, calculating the percentage of adverse effects obtained after carrying out the tests as well as the severity of them. MATERIAL AND METHODS A prospective experimental study was conducted, selecting patients who come to the office of Pediatric Allergy with allergic rhinitis with or without asthma, in which sensitization was detected by skin tests and specific serum IgE (for complete extract and for molecular components) for three or more aeroallergens. In these patients, nasal provocation test were performed at single concentration, for detected sensitizations. Nasal provocation test were performed by applying the suspected allergen in aerosol and measuring the response generated by acoustic rhinometry and triggered symptomatology. Up to three provocations were performed for each session, stopping it in case of a positive provocation. Adverse effects produced after the provocation were recorded, Medication necessary to control them and symptom questionnaire were delivered to control the adverse effects in the days immediately following the provocation RESULTS 56 patients were selected, performing 209 nasal provocations. Mean sensitization was 5.18 sensitizations per patient. Most frequent sensitizations were pollens from olive tree (91%), salsola (75%) and grasses (62%), house dust mites (46%), alternaria (46%) and fur animals (cat 46%, dog 42 %). Provocations were positive in 77% of those performed for mites, 67% for fur animals (cat and dog), 87% for alternaria, 25% for olive tree pollen, 46% for salsola pollen and 13% for grass pollen. Overall, 49% of the provocations were positive. Only in mites differences were found between papular size and IgE levels (complete extract and Der p2) between patients with positive PPN and those with negative PPN. Provocations required an average of 3.73 sessions per patient, but two sessions were enough to complete the study in 53% of the cases. Adverse effects were registered in 13% of the PPNs performed, with no serious adverse effect detected. CONCLUSIONS 1. Allergen-specific nasal provocation test is not a test equivalent to the rest of the diagnostic tests that detect allergic sensitization. 2. No cut-off points have been detected in the size of the papule or specific IgE figures that predict the positive or negative result of the nasal provocation test 3. Nasal provocation test performed at a single concentration allows different allergens to be tested in the same provocation session, which saves time in the etiological diagnosis 4. Nasal provocation test performed in polysensitized children with allergic rhinitis with or without asthma is a safe test. 5. Nasal provocation test performed at a single concentration is a diagnostic test applicable in any type of allergy unit.