Use of Dipstick Assay and Rapid PCR-DNA Analysis of Nasal Secretions for Diagnosis of Bacterial Sinusitis in Children With Chronic Cough

Song, Charles; Chorath, Jeena; Pak, Youngju; Redjal, Nasser

ghing in both entities. Such coexistence (via "one airway") needs to be explored in the future. In group 1B, chronic cough was most likely due to postnasal drip resulting from nonbacterial pathologies such as allergy (91% of the patients had allergen sensitization as shown in Table 1 ), viral infection, or chronic irritation. Although SA was present as dominant species in 2 patients in this group, its pathogenic role is doubtful due to their presence in control groups 2 and 3. Staphylococci were present in the sinus aspirates of acute, 29 chronic sinusitis, 14, 20, 21 and in the nasal cavities of those with CRS with nasal polyps, 16 and may play a role in the pathogenesis of sinusitis, especially in adults. 32, 33 But they were also shown to be present in the nasal cavities of 25% to 30% of asymptomatic subjects 30 in a competing relationship with PNPB, 22 and their presence may be a transient colonization rather than infection. 36 The presence of PNPB in all groups (Table 2 and Figure 1 ) is consistent with the recent studies revealing asymptomatic cohorts also carry diverse commensal bacteria in the nasal cavities including SA, SE, DP, and CP, and they maintain competing relationship among themselves. 20, 22 An intriguing finding was the presence of rhinovirus in all groups including asymptomatic controls, indicating that its colonization was not necessarily associated with clinical symptoms. In group 1A, 60% of the patients carried PPV and 40% carried both PPB and PPV indicating that both viruses and bacteria were coexistent. Rhinovirus, the most common viral pathogen in our study, was shown to increase adhesion of PPB to nasal epithelial cells at least 2-fold compared to uninfected controls. 37, 38 Conclusion We demonstrated, as others have, in children with chronic cough with sinusitis, microbial balance of the sinus cavity is disturbed and PPB takes the dominance. This can be detected by simple methods: dipstick assay and quantitative DNA-PCR test of the nasal secretion. Therefore, we recommend that clinicians utilize these methods as an alternative to imaging studies to make a diagnosis of bacterial sinusitis and offer a specific therapy for the pathogens in a rapid and accurate manner. Further studies are indicated to replicate these findings and refine the potential diagnostic capabilities of DNAbased methods for bacterial sinusitis and bronchitis.