1018. Title: Etiology, Prognosis, and Inflammatory Markers in Pediatric Community-Acquired Pneumonia
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 and result in unnecessary antibiotic use. There are limited data using inflammatory markers to differentiate pneumonia etiology in children. We examined the utility of inflammatory markers [procalcitonin (PCT), serum triggering receptor expressed on myeloid cells 1 (sTREM-1)] and cytokines in predicting etiology and severity of pneumonia in hospitalized children.

Methods:

Children <18 years-old hospitalized with pneumonia were enrolled in the CDC pneumonia etiology study based on clinical and radiographic criteria. Blood for culture and Streptococcal polymerase-chain-reaction (PCR) and naso/oropharyngeal swabs for atypical bacteria and respiratory viral PCR were collected. PCT, sTREM-1, and cytokines (IL-1, 6,8,10 & 12, TNFα, INFα,γ) were measured on serum collected within 48 hrs of admission. Patients were categorized into 5 groups: single virus (V), co-viral (VV), bacterial (B), bacterial-viral (BV), and unknown (U). Severe disease was classified as requiring ICU admission. Kruskal-Wallis and Mann-Whitney U were used to assess association of median inflammatory marker levels with etiology and severity respectively.

Results: 

From January to September 2010, 85/169 enrolled children with pneumonia had serum available for analysis; 15% required ICU admission. V, VV, BV, and U etiology were found in 46%, 24%, 7%, and 23% of children; none had bacterial etiology alone. PCT (0.39 vs 0.7 vs 2.2 ng/ml, P=0.6) and sTREM-1 (1155 vs 1125 vs 1184 pg/ml, P=0.42) were similar among V, VV, and BV groups. A difference in IL-6 (13.03 vs 96.8 pg/ml, P=0.003) and TNFα (26.5 vs 77.1 pg/ml, P=0.02) between V and BV groups was observed. Among all markers, only elevated IL-8 (44.2 vs 26.5 pg/ml, P=0.05) was associated with ICU admission.

Conclusion: 

Preliminary data suggests serum PCT, sTREM-1, and cytokines have limited value in determining pneumonia etiology or in predicting ICU admission. Although higher IL-6 and TNFα values were seen in children with BV co-infection and IL-8 in children admitted to the ICU, the sample size is too small to be definitive.  Applicability of these inflammatory markers to classify etiology and predict severity in pediatric pneumonia remains to be defined.


Subject Category: D. Diagnostic microbiology

Fouzia Naeem, MD1,2, Jody Cockroft, BS1, Noel Lenny, PhD3, M. Naeem Shaikh, MBBS1, Randall Hayden, MD2, Anami Patel, PhD1,3, Nick Van de Velde, PhD2, Carl Johnson, MT(ASCP)2, Patricia Flynn, MD2, Seema Jain, MD4, Jonathan A. McCullers, MD2 and Sandra R. Arnold, MD1,3, (1)University of Tennessee Health Science Center, Memphis, TN, (2)St. Jude Children's Research Hospital, Memphis, TN, (3)Le Bonheur Children's Hospital, Memphis, TN, (4)Influenza Division, Centers for Disease Control and Prevention, Atlanta, GA

Disclosures:

F. Naeem, None

J. Cockroft, None

N. Lenny, None

M. N. Shaikh, None

R. Hayden, None

A. Patel, None

N. Van de Velde, None

C. Johnson, None

P. Flynn, Bristol Myers Squibb: Research Contractor, Research support
Tibotec: Research Contractor, Research support

S. Jain, None

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

S. R. Arnold, None

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.