Skip to main content

Maxillary sinusitis: classification and microbiology

Classification
Maxillary sinusitis refers to the inflammation and infection of the maxillary sinuses. The sinusitis is categorized based on its etiology and symptom duration. According to etiology, the maxillary sinusitis could be of odonotgenic and non-odontogenic origin. Just 10% of all maxillary sinusitis cases are of odontogenic origin. Non-odontogenic factors, such as allergic reactions and infections of the upper respiratory tract, are primary cause of the sinusitis. Based on duration of the sinus infection’s symptoms, infectious maxillary sinusitis is divided into two (2) categories: acute and chronic.  
Acute maxillary sinus infection’s symptoms, such as purulent nasal discharge accompanied by facial fullness, pressure or pain, and / or nasal congestion, last up to twenty-one (21) days. However, chronic maxillary sinus infection’s symptoms persist for more than two and a half months.
Microbiology
An array of bacterial pathogens causes maxillary sinusitis. The pathogen pattern may vary with individual characteristics of the patient and chronicity of the disease. The primary cause of acute sinus infection is facultative and aerobic organisms, whereas gram-negative rods and anaerobes are mainly responsible for chronic sinus infection.
Several studies focusing on the maxillary sinus microbiology have been conducted, as it is quite safe and easy to access the sinus. Thorough knowledge of bacteriology of maxillary sinusitis will facilitate accurate and successful therapy with a little side effect. For example, the bacteriology study helps in limiting the misuse of antibiotics.
The bacteriological analysis of the sinus also enables documentation of antibiotics and surgical processes’ effectiveness, helping in developing novel therapies. Scientists use both traditional and modern methods and techniques to investigate the bacteria profile. For instance, earlier, the contents of the sinus were only sampled directly, whereas today the direct sample analysis is studied with findings of the minimally invasive procedures using state-of-the-art endoscopic technology.
Prior to the discovery of endoscopes, the maxillary sinus was punctured through the inferior meatus or canine fosa to collect the cultures. However, the traditional procedure not only creates discomfort but also has many other limitations. With the launch of sinonasal endoscopy technology in the1980s, endoscopically guided middle meatus (EGMM) cultures became a reality. A small wire tipped with calcium alginate is used for swabbing the meatus under endoscope.
EGMM vs. MSP
During comparison of EGMM and maxillary sinus puncture (MSP) cultures, it is found out that the former has higher sensitivity and specificity than the latter.  In fact, after some practice, doctors can obtain EGMM cultures easily, and thereby reducing contamination risk, chances of morbidity and discomfort level in patients.