Children with severe pneumonia had higher percentages of serumeosinophilia (88% vs 40%, P<0.001), asthma (65% vs 35%, P=0.011), allergic rhinitis (71% vs 40%, P=0.009), and IgE level (P=0.007). We found positive correlations between aeroallergen sensitizations and severity of pneumonia (82% vs 53%, P=0.007).