Results:
Records from a total of 43 children ≤ 36 months old [median 14 months (range 3-36 months)] on ICS therapy were included in the analysis. The majority of patients were API positive. (Table 1). Median BAL eosinophil percentages were low in both API -ve and API +ve groups and were comparable to expected normal values from the literature17 with a median (range)of 1% (1-2%) in API -ve and 1% (1-11%) in API +ve patients (Figure 1-a). Only 3 patients with +ve API had eosinophils ≥ 2%. Increased neutrophil percentages compared to literature controls17 were present in both API groups with a median 16% neutrophils (1-76%) in API -ve and 42% neutrophils (1-95%) in API +ve patients; (P = 0.09). (Figure 1-a). Cell percentages (median (range)) were similar for lymphocytes and macrophages between API groups with 12% lymphocytes (1-30%) in API -ve and 7% lymphocytes (1-37%) in API +ve groups; 67.5% macrophages (12-97%) in API -ve and 41% macrophages (2-94%) in API +ve groups (Figure 1-a). No difference was found between any cell type percentage comparing API groups after exclusion of samples with positive BAL cultures (bacterial and viral) (Figure 1-b); however, neutrophil percentages remained higher than expected in both groups. Patients with positive cultures (bacterial or viral) had significantly higher neutrophil percentages compared to patients with negative cultures in both API groups in combined (p=0.0001) . (Figure 2, Table 2).
There was no significant difference in culture results (bacterial and viral) comparing API groups (Table 1). There was correlation between neutrophil percentages and positive bacterial (R=0.6, p ‹0.001) and viral cultures (R=0.3, p=0.01). 25% of total patients had mixed (bacterial and viral) cultures. M. catarrhalis was the most commonly isolated organism (8 patients), followed by Streptococcus pneumoniae (5 patients) and a significant growth of mixed organisms (5 patients). Two patients grew H. influenzae . Viruses isolated include Rhinovirus (3 patients) Coxackie/Echo virus (4 patients), Adenovirus (2 patients) and CMV (1 patient). Three patients had a mixed culture of CMV with another virus (Rhinovirus, Coxackie virus and Corona virus). One patient had a mixed culture of Adenovirus with Parainfluenza virus. Thirty three percent of all patients had LLM% ≥ 20% in their BAL; however, LLM% did not differ by API, culture status, or cell percentages.