Infections: Nose - Infections -

Nose - Infections

Infections:

Inflammatory disease , mostly in the form of the common cold, as everyone knows are the most common disorders of the nose and accessory air sinuses. Most of these inflammatory conditions are viral in origin, but they are often complicated by superimposed bacterial infections having considerably greater significance. Much less common are a few destructive inflammatory nasal disease and tumors primary in the nasal cavity or paranasal sinuses.

Inflammations

Infectious Rhinitis

Infectious rhinitis, the more elegant way of saying common cold, is most instances caused by one or more viruses. Major offenders are adenoviruses, echoviruses, and rhinoviruses. They evoke a profuse catarrhal dischange that is familiar to all and the bane of the kindergarten teacher. During the initial acute stages, the nasal mucosa is thickened, edematous and red the nasal cavities are narrowed; and the turbinates are enlarged. These changes may extend producing a concomitant pharyngotonsillitis. Secondary bacterial infection enhances the inflammatory reaction and produces an essentially mucopurulent or sokmetimes frankly supporative exudate. But as everyone knows, these infections soon clear up, usually in a week if appropriately treated but only after 7 days if ignored.

Allergic Rhinitis

Allergic rhinitis (hay fever) is initiated by sensitivity reactions to one of a large group of allergens, most most commonly the plant pollens, fungi, animal allergens and dust mites. It affects 20% of the U.S. population. As is the case with asthma, allergic rhinitis is an immunoglobulin E-mediated immune reaction with an early- and late phase response. The allergic reaction is characterized by marked mucosal edema, redness, and mucous secretion, accompanied by a leukocytic infiltration in which eosinophils are prominent.

Nasal Polyps

Recurrent attacks of rhinitis eventually lead to focal protrusions of the mucosa, producing so called nasal polyps, which may reach 3 to 4 cm in length. On histologic examination, these polyps consists of edematous mucoa having a loose stroma, often harboring hyperplastic or cystic mucous glands and infiltrated with a variety of inflammatory cells, including prominently neutrophils, eosinophils, and plasma cells with occasional clustes of lymphocytes. In the absence of bacterial infection, the mucosal converting of these polyps is intact but with chronicity, it may become uncerated or infected. When multiple or large they may encroach on the airway and impair sinus drainage. Although the features of nasal polyps point to an allergic etiology most patients with nasal polyps point to an allergic etiology most patients with nasal polyps are not atopic and only 0.5% of atopic patients develop polyps.

Chronic Rhinitis

Chronic rhinitis is sa sequel to repeated attacks of acute rhinitis, whether microbial or allergic in origin with the eventual development of superimposed bacterial infection. A deviated nasal septum or nasal polyps with impaired drainage of secretions contribute to the microbial invasion. Frequently there is superficial desquamation or ulceration of the mucosal epithelium and a variable inflammatory infiltrate of neutrophils, lymphocytes, and plasma cells subjacent to the epithelium. These supprative infections sometimes extend into the air sinuses.

Sinusitis

Acute sinusitis is most commonly preceed by acute or chronic rhinitis, but maxillary sinusitis occasionally arises by extension of a periapical infection through the bony floor of the sinus. The offending agents are usually inhabitants of the oral cavity, and the inflammatory reaction is entirely nonspecific. Impairment of drainage of the sinus by inflammatory edema of the mucosa is an important contributor to the process and when complete may impound the suppurative exudate, producing empyema of the sinus. Obstruction of outflow, most often of the frontal and next most often of the anterior ethmoid sinuses, occasionally leads to an accumulation of mucous secretions in the absence of direct bacterial invasion, producing a so called mucocele. Acute sinusitis may in time give rise to chronic sinusitis, particularly when there is interference with drainage. There is usually a mixed microbial flora largely of normal inhabitants of the oral cavity. Particularly severe forms of chronic sinusitis are caused by fungi, especially in diabetics. Uncommonly sinusitis is a compenent of Kartaener syndrome, which also includes bronchiectasis and situs inversus.