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

Background: Chronic cough in children is a diagnostic challenge.

Objective: To discover the utility of nasal dipsticks and polymerase chain reaction (PCR)-DNA analysis in differentiating bacterial sinusitis from other causes of chronic cough and identifying pathogens from the nasal cavity.

Method: We recruited 22 patients under 15 years of age with cough lasting longer than 4 weeks (group 1), 7 controls with allergic rhinitis (group 2), and 10 controls without respiratory symptoms (group 3). Based on symptoms, the results of nasal secretion assays, and nasal endoscopy, a diagnosis of clinical bacterial sinusitis was made. We identified potential pathogens by quantitative PCR of nasal secretions.

Results: Group 1A (cough with clinical bacterial sinusitis n = 10): Eight (80%) patients had bacterial sinusitis associated with dominant potential pathogenic bacteria (PPB): Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. Group 1B (cough without clinical bacterial sinusitis n = 12): None had dominant PPB. Group 2 (allergic rhinitis n = 7): None had dominant PPB. Group 3 (asymptomatic n = 10): None had dominant PPB. Twenty to 57% of all groups were colonized with Staphylococcus aureus. Fifty to 70% were colonized with Staphylococcus epidermidis, Corynebacterium pseudodiphtheriticum, and Dolosigranulum pigrum.

Conclusion: In children with chronic cough, clinicians can utilize a simple and inexpensive nasal secretion dipstick assay for rapid diagnosis of sinusitis and identify PPB by DNA-PCR test for specific antibiotic treatment.