A total of 226 patients diagnosed with DNI were included in the study. The patients were from a diverse range of backgrounds and included both inpatients and outpatients. Of these patients, 135 (59.7%) were male. The median age was 39.5 years (interquartile range [IQR]: 29–58). Comorbidities were present in 87 patients (38.5%), with hypertension (20.3%) and diabetes mellitus (19.0%) being the most common. Odontogenic infection was the most prevalent etiology (54.9%), followed by pharyngeal and salivary gland infections. The primary presenting symptoms were neck pain and swelling (67.7%), fever (30.9%), and dysphagia (14.6%).
The buccal space was the most frequently affected site (22.6%), followed by the peritonsillar space (20.3%) and the submandibular space (19.9%). Klebsiella pneumoniae was the most identified pathogen (20%), followed by Staphylococcus spp. and Viridans streptococcus. (Fig. 1) Treatment modalities included incision and drainage (44.6%), simple aspiration (12.4%), and conservative management with intravenous antibiotics (42.9%). The choice of treatment was based on the severity of the infection, the patient's overall health status, and the presence of any complications. Focus on complication and no complication groups (Table 1, Table 2). The median age of patients with complications was significantly higher (52 years, IQR: 31–63) compared to those without complications (37 years, IQR: 29–56) (p = 0.0423). Patients with complications had a higher prevalence of underlying medical conditions (62.16%) compared to those without complications (33.86%) (p = 0.001), with diabetes mellitus being more common in the complication group (37.48%) than in the no complication group (15.34%) (p = 0.001).
Neck swelling was significantly more common in patients with complications (84.49%) compared to those without complications (64.02%) (p = 0.008). Fever was more frequently observed in the complication group (54.05%) compared to the no complication group (26.46%) (p = 0.001). Difficulty breathing was exclusively observed in the complication group (21.62%) and was absent in patients without complications (p < 0.001). The overall mortality rate was 0.89%.
Multiple space involvement defined by at least two space involvement was significantly higher in the complication group (64.86%) compared to the no complication group (18.52%) (p < 0.001). Submandibular space involvement was more common in the complication group (40.54%) compared to the no-complication group (15.87%) (p = 0.001). Submental space involvement was also significantly higher in patients with complications (21.62%) compared to those without (7.94%) (p = 0.012). Buccal space involvement was more frequent in the complication group (35.14%) compared to the no-complication group (20.11%) (p = 0.046).
Temporal space involvement was observed only in the complication group (3.5%) and not in the no-complication group (p < 0.001). Lingual space involvement was higher in the complication group (10.81%) compared to the no-complication group (3.17%) (p = 0.039). Ludwig space involvement was significantly more common in the complication group (13.51%) compared to the no-complication group (1.59%) (p < 0.001).
Our findings regarding treatment modalities indicate that 44.6% of patients underwent incision and drainage, 12.4% underwent simple aspiration, and 42.9% received conservative treatment with intravenous antibiotics.
Complications occurred in 16.4% of cases, with airway obstruction being the most common (7.1%), followed by sepsis (4.9%). The median length of hospital stay was significantly longer for patients with complications (14 days, IQR: 9–22) compared to those without complications (4 days, IQR: 3–6) (p < 0.001). Sepsis at admission was present in 29.73% of patients with complications and absent in those without complications (p < 0.001). Pneumonia occurred in 16.22% of the complication group and was absent in the no complication group (p < 0.001). Upper airway obstruction occurred in 43.24% of patients with complications and was absent in those without complications (p < 0.001). Emergency tracheostomy due to upper airway obstruction was required in 5.41% of patients with complications (p < 0.001). The overall mortality rate was 0.88% (5.4% in the complication group and 0% in the no complication group (p < 0.001).
Multiple logistic regression analysis was performed to identify the factors associated with complications. This analysis considers the potential influence of multiple variables on the outcome. The factors found to be significantly associated with complications were space involvement in the parapharyngeal space (odds ratio 43.3, p = 0.006), involvement of multiple spaces (odds ratio 7.98, p < 0.001), and involvement of the submental space (odds ratio 5.5, p = 0.017). The presenting symptoms of fever (odds ratio 6.1, p = 0.008), anemia (odds ratio 37.4, p = 0.024), and neck pain and swelling (odds ratio 0.2, p = 0.045) were also associated with complications.