1019. The Utility of Induced Sputum Culture in the Diagnosis of Community-Acquired Pneumonia among Hospitalized Children
Session: Poster Abstract Session: Diagnosing Pneumonia and Meningitis
Saturday, October 22, 2011
Room: Poster Hall B1
Background: Signs and symptoms of bacterial and viral pneumonia may overlap, resulting in unnecessary antibiotic use. New molecular techniques have improved respiratory viral identification from the upper airway but bacteria remain elusive as blood culture is insensitive. Sputum examination is attractive as it could provide access to lower respiratory tract bacteria using a non-invasive technique.

Methods: Children <18 years old hospitalized with pneumonia were enrolled in an ongoing CDC pneumonia etiology study based on clinical and radiographic criteria. Blood for culture and Streptococcal polymerase-chain-reaction (PCR) was collected; pleural fluid samples were obtained if therapeutic thoracentesis was required. Children received nebulized albuterol followed by 7% saline to induce deep cough. Expectorated sputum was collected directly into a sterile container or via suction catheter. Specimens were processed immediately.  Sputa were considered to be good quality if the gram stain had a white blood count >25 and epithelial cells <10 per low power field. Culture was performed for bacterial pathogens including S. pneumoniae (SP), Hemophilus influenzae(HF), S. pyogenes (GAS),  Staphylococcus aureus (SA), and Moraxella catarrhalis (MC).

Results: From January to August 2010, 172 children with radiographic pneumonia had sputum available for culture.  Twenty-nine (17%) sputum samples were of good quality, fifteen were culture negative for potentially pathogenic organisms. Of the 14 sputa with positive culture, 13 gram stains demonstrated multiple bacterial morphologies; eight had gram stains demonstrating bacteria consistent with the cultured organism(s). Nine cultures grew single pathogens: methicillin-resistant SA (2) (MRSA), SP (2), and HF (5).  Five children had polymicrobial cultures with MRSA/SP (2), SP/MC (1), HF/MC (1) and SP/HF/MC/GAS (1).  Only one child with high quality sputum had a positive sterile site culture with SP from blood; this patient grew MRSA from sputum.

Conclusion: While there were few good quality specimens early in the study, these specimens yielded multiple potential pathogens.  Sputum induction may be helpful for identifying lower respiratory pathogens in pediatric pneumonia but additional data are needed.


Subject Category: D. Diagnostic microbiology

Sandra R. Arnold, MD1,2, Jody Cockroft, BS2, Fouzia Naeem, MD2,3, M. Naeem Shaikh, MBBS2, Anna M. Bramley, MPH4, Seema Jain, MD4 and Jonathan A. McCullers, MD3, (1)Le Bonheur Children's Hospital, Memphis, TN, (2)University of Tennessee Health Science Center, Memphis, TN, (3)St. Jude Children's Research Hospital, Memphis, TN, (4)Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA

Disclosures:

S. R. Arnold, None

J. Cockroft, None

F. Naeem, None

M. N. Shaikh, None

A. M. Bramley, None

S. Jain, None

J. A. McCullers, AVIBioPharma: Consultant, Consulting fee
GlaxoSmithKline: Consultant, Consulting fee
Novartis: Consultant, Consulting fee
Pfizer: Consultant, Consulting fee

Findings in the abstracts are embargoed until 12:01 a.m. EST Thursday, Oct. 20 with the exception of research findings presented at IDSA press conferences.