Predictors of occult pneumococcal bacteremia in young febrile children in the era of pneumococcal conjugated vaccine Mintegi Raso S, Benito Fernández J, Iturralde Orive I, Dopazo L Paediatric Emergency Department. Hospital Cruces. Bilbao. Basque Country Mintegi Raso S, Benito Fernández J, Iturralde Orive I, Dopazo L Paediatric Emergency Department. Hospital Cruces. Bilbao. Basque Country

Background Classically reported, well-appearing children aged 3-36 months with FWS>39ºC, pneumococcal occult bacteremia (PnOB) rate: –> WBC/mmm 3 : 6% –> ANC /mmm 3 : 8% Classically reported, well-appearing children aged 3-36 months with FWS>39ºC, pneumococcal occult bacteremia (PnOB) rate: –> WBC/mmm 3 : 6% –> ANC /mmm 3 : 8%

Background Changes in PnOB prevalence and distribution of serotypes due to PCV-7 may have altered the yield of complete blood count (CBC) in order to select patients at risk of having PnOB.

Objective To analyze the yield of the CBC in order to identify children at risk for PnOB in the era of PCV-7.

Methods Retrospective review –Well appearing children 3 to 36 months of age, FWS –presenting to the PED of a tertiary teaching hospital (Hospital Cruces, Basque Country) –October 1, 2004 and September 30, 2006 –CBC and a blood culture (BC) performed as part of their evaluation for fever Patients with altered urinanalysis were excluded. n=1586 Retrospective review –Well appearing children 3 to 36 months of age, FWS –presenting to the PED of a tertiary teaching hospital (Hospital Cruces, Basque Country) –October 1, 2004 and September 30, 2006 –CBC and a blood culture (BC) performed as part of their evaluation for fever Patients with altered urinanalysis were excluded. n=1586

Results Positive blood culture : –16 children 1% –Pneumococcus11 0.7%

PPV 1,64 NPV 99,8 PPV 1,95 NPV 99,7 Results – PPV of WBC and ANC

Results – PCV7-bacteremia rate Doses of PCV-7PnOB rate Less than 20.82% 2 or more0.23%

Results – PPV related with doses of PCV-7

Limitations Retrospective study Not-multicenter Inclusion only of those well-appearing children aged 3 to 36 months with FWS  39ºC, in which physician obtained a CBC and blood culture as part of their evaluation for fever Retrospective study Not-multicenter Inclusion only of those well-appearing children aged 3 to 36 months with FWS  39ºC, in which physician obtained a CBC and blood culture as part of their evaluation for fever

Conclusions In the era of PCV-7, rate of PnOB is different in children related with the pneumococcal vaccination status. The yield of the CBC is lower than in the pre-vaccinal era. Decisions based on the analytical results must be reconsidered, mainly in the infants with at least 2 doses of VCN. In the era of PCV-7, rate of PnOB is different in children related with the pneumococcal vaccination status. The yield of the CBC is lower than in the pre-vaccinal era. Decisions based on the analytical results must be reconsidered, mainly in the infants with at least 2 doses of VCN.