Sestre Milosrdnice University hospital and Institute of Clinical Medical Research
Abstract
Bronchial hyperreactivity denotes an enhanced bronchial response to usual physiological stimuli, and can manifest with cough or paroxysmal cough through tussive syncope and bronchospasm. Bronchial hyperreactivity can be transient or permanent. Transient bronchial hyperreactivity occurs in acute inflammation of the upper and lower airways, and manifests with dry irritation cough that may persist for up to two months. Permanent bronchial hyperreactivity is found in 10% - 50% of patients with allergic rhinitis, 50% of patients with chronic bronchitis, and 100% of patients with asthma. The pathophysiological mechanism of bronchial hyperreactivity in patients with allergic rhinitis has not yet been fully clarified, however, the following theories have been implicated: loss of nasal function, direct aspiration of inflammatory secretion and antigens, aerogenic transfer of antigens depending on particle size, gastroesophageal reflux, neurogenic mechanisms including the action of neuropeptides in the onset of neurogenic inflammation, and the concept of allergic reaction as a systemic response to local antigen presentation. It should be noted that bronchial hyperreactivity is not asthma; however, the clinical manifestation of asthma is just a matter of time. Therefore, allergic rhinitis should be considered a predisposing factor for the occurrence of asthma.Pod bronhijalnom hiperreaktivnošću podrazumijeva se pojačan odgovor bronha na uobičajene fiziološke podražaje, koji se može očitovati kašljem, paroksizmom kašlja, sve do tusigene sinkope i bronhospazma. Bronhijalna hiperreaktivnost može biti prolazna i trajna. Prolazna bronhijalna hiperreaktivnost pojavljuje se kod akutnih upala gornjih i donjih dišnih putova, očituje se suhim podražajnim kašljem koji može potrajati i do dva mjeseca. Trajna bronhijalna hiperreaktivnost nalazi se u 10% - 50% bolesnika s alergijskim rinitisom, 50% bolesnika s kroničnim bronhitisom, te u 100% bolesnika s astmom. Patofiziološki mehanizam nastanka bronhijalne hiperreaktivnosti u bolesnika s alergijskim rinitisom nije u potpunosti jasan, a spominju se slijedeće teorije: gubitak funkcije nosa, izravna aspiracija upalnog sekreta i antigena, aerogeno prenošenje antigena ovisno o veličini cestica, gastroezofagusni refluks, neurogeni mehanizmi uključujući i djelovanje neuropeptida u nastanku neurogene upale, te shvaćanje alergijske reakcije kao sistemske reakcije na lokalno prikazivanje antigena. Valja istaknuti da bronhijalna hiperreaktivnost nije astma, ali je pitanje dana kada će se astma klinički očitovati. Stoga se alergijski rinitis može smatrati predisponirajućim čimbenikom u pojavi astme
