Sinus Inflammatory Disease

Dr.Ahmad

Sinus Inflammatory Disease



Sinusitis is a clinical diagnosis based on patient signs and symptoms. 10 The Task Force on Rhinosinusitis (sponsored by the American Academy of Otolaryngology–Head and Neck Surgery) has established criteria to define "a history consistent with sinusitis" (Table 17-2). To qualify for the diagnosis, the patient must exhibit at least two major factors or one major and two minor factors. The classification of sinusitis as acute versus subacute or chronic is based on the time course over which those criteria have been met. If signs and symptoms are present for at least 7 to 10 days, but for less than 4 weeks, the process is designated acute sinusitis. Subacute sinusitis is present for 4 to 12 weeks and chronic sinusitis is diagnosed when the patient has had signs and symptoms for at least 12 weeks.

[FONT=&quot]a[/FONT][FONT=&quot]Either two major factors or one major and two minor factors are required. Purulence on nasal endoscopy is diagnostic. Fever is a major factor only in the acute stage

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[FONT=&quot]Acute sinusitis typically follows a viral upper respiratory infection whereby sinonasal mucosal inflammation results in closure of the sinus ostium. This results in stasis of secretions, tissue hypoxia, and ciliary dysfunction. These conditions promote bacterial proliferation and acute inflammation. The mainstay of treatment is oral antibiotics empirically directed toward the three most common organisms S. pneumoniae, H. influenzae, and M. catarrhalis. 11 As with otitis media, antibiotic resistance is a mounting concern. Nosocomial acute sinusitis frequently involves Pseudomonas or S. aureus, both of which may exhibit significant antibiotic resistance. Other treatments include topical and systemic decongestants, nasal saline spray, topical nasal steroids, and oral steroids in selected cases. In the acute setting, surgery is reserved for complications or pending complications, which may include extension to the eye (orbital cellulitis or abscess) or the intracranial space (meningitis, intracranial abscess). It should also be noted that, strictly speaking, a viral upper respiratory infection (common cold) is a form of acute sinusitis. The working definition outlined above, however, attempts to exclude these cases by requiring that symptoms be present for at least 7 to 10 days, by which time the common cold should be in a resolution phase. Use of this modified working definition avoids unnecessary antibiotic prescriptions and further promotion of resistance.[/FONT]

[FONT=&quot]Chronic sinusitis represents a heterogeneous group of patients with multifactorial etiologies contributing to ostial obstruction, ciliary dysfunction, and inflammation. Components of genetic predisposition, allergy, anatomic obstruction, bacteria, fungi, and environmental factors play varying roles, depending on the individual patient. As of yet, no immunologic "final common pathway" has been defined, but the clinical picture is well described. Diagnosis is suspected according to the criteria described previously. Chronic sinusitis may also be associated with nasal polyps, which are manifestations of longstanding mucosal inflammatory disease. Polyps themselves may further block sinus outflow, resulting in further stasis of secretions and bacterial proliferation.[/FONT]

[FONT=&quot]Nasal endoscopy is a critical element of the diagnosis of chronic sinusitis. Anatomic abnormalities, such as septal deviation, nasal polyps, and purulence may be observed (Fig. 17-5 and Fig. 17-6). The finding of purulence by nasal endoscopy is diagnostic of sinusitis, regardless of whether other criteria are met. In a setting in which symptoms persist for at least 12 weeks, purulence on nasal exam represents an acute exacerbation of chronic sinusitis. Pus found on endoscopic exam may be cultured, and subsequent antibiotic therapy can be directed accordingly. The spectrum of bacteria found in chronic sinusitis is highly variable and includes higher prevalences of polymicrobial infections and antibiotic-resistant organisms. Overall, S. aureus, coagulase-negative staphylococci, gram-negative bacilli, and streptococci are isolated, in addition to the typical pathogens of acute sinusitis[/FONT]

The diagnosis of chronic sinusitis can be confirmed by CT scan, which demonstrates mucosal thickening and/or sinus opacification (Fig. 17-7). It should be underscored, however, that CT scan is probably not the diagnostic gold standard because many asymptomatic patients will demonstrate findings on sinus CT scan. Also, patients with positive findings on nasal endoscopy may have normal CT scans. Overall, the decision to treat medically should be based upon patient history and nasal endoscopy, rather than results of the CT scan. Furthermore, over 75% of patients with normal findings on nasal endoscopy will have normal CT scans, underscoring the importance of endoscopy in the decision-to-treat process. Although acute sinusitis is often treated empirically by the primary care practitioner, when clinical criteria for chronic sinusitis are met, this typically prompts otolaryngology referral for nasal endoscopy, aggressive medical therapy, and possibly surgery.

Medical management of chronic sinusitis includes a prolonged course of oral antibiotics for 3 to 6 weeks, oral steroids, and nasal irrigations with saline or antibiotic solutions. 12 Underlying allergic disease is managed with antihistamines and possible allergy immunotherapy. Those failing medical management are candidates for elective surgery, where the goals are to enlarge the natural sinus ostia (Fig. 17-8) and to remove chronically infected bone to promote both ventilation and drainage of the sinus cavities. Eventual resolution of the chronic inflammatory process can be attained with a combination of surgery and aggressive medical therapy. Surgery is most often performed with endoscopic techniques.

The role of fungi in sinusitis is an area of active investigation. 13,14 Fungal sinusitis may take on both noninvasive and invasive forms. The noninvasive form includes the presence of a fungal ball and allergic fungal sinusitis, both of which occur in immunocompetent patients.

A fungal ball is typically seen in individuals with chronic (or recurrent acute) symptoms that are often subtle and limited to a single sinus. Patients may complain about the perception of a foul odor and occasionally report expelling fungal debris upon nose blowing. A fungal ball (Fig. 17-9) consisting of Aspergillus fumigatus is usually found in the maxillary sinus, with scant inflammatory cell infiltration. Surgery to remove the fungal ball and reestablish sinus ventilation is almost always curative. This can be accomplished endoscopically.

Allergic fungal sinusitis involves hypersensitivity (types I and III) reactions to fungal antigens within the nose and sinuses. Patients often present with chronic sinusitis that has been especially refractory to medical management. Endoscopic evaluation reveals florid polyposis and inspissated mucin containing fungal debris and products of eosinophil breakdown. The implicated organisms are usually those of the Dematiaceae family, but Aspergillus species are also seen. Treatment includes systemic steroids, surgery, and nasal irrigations. Oral antifungal therapy is sometimes indicated as well.

Immunocompetent patients may also develop an indolent form of invasive fungal sinusitis, but more commonly, invasive fungal sinusitis affects immunocompromised patients, diabetics, or the elderly. 15 Fungal invasion of the microvasculature causes ischemic necrosis and black, necrotic escharation of the sinonasal mucosa. Aspergillus and fungi of the Mucoraceae family are often implicated with the latter more common in diabetic patients. Treatment requires aggressive surgical débridement and IV antifungals, but the prognosis is dismal.



sourcs : Schwartz's Surgery 8e

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