[Blood cultures in the emergency department].
BACKGROUND
Culture of emergency room blood samples is common practice, but open to controversy. As compared to other emergency tests, blood collection requires twice as much time and needs a refined technique to avoid contamination, and the study has no immediate diagnostic utility.


METHODS
This prospective study includes consecutive adult patients with positive emergency room blood cultures. We analyzed the diagnostic sensitivity and contamination rate of the cultures and the etiology, clinical features and prognosis of the bacteremias encountered.


RESULTS
During the study period, 5.2 blood cultures were indicated per 1000 patients attended in the emergency room. The diagnostic yield (positive blood cultures/total cultures) was 20% and the contamination rate (contaminated blood cultures/total cultures) was 1%. The incidence of bacteriemia was 0.99 episodes per 1000 patients attended in the emergency room and 10.3 episode per 1000 hospitalized patients. Gram-negative bacteria predominated (57%). Sepsis was the most frequent clinical manifestation (50%), followed by severe sepsis (40%) and septic shock (10%). Mortality was 22%. Diabetes mellitus and severe sepsis/septic shock were independent factors associated with mortality.


CONCLUSIONS
Diagnostic performance and quality of emergency room blood cultures was high. The predominant etiology was gram-negative bacteria. Patients had a severe clinical presentation. Diabetes mellitus and severe sepsis and/or septic shock were independent prognostic factors of mortality.
Cisneros-Herreros
José Miguel
JM
Servicio de Enfermedades Infecciosas, Hospitales Universitarios Virgen del Rocío, Sevilla, Spain. cisnerosjm@telefonica.net
Sánchez-González
Manuela
M
Prados-Blanco
M Trinidad
MT
Llanos-Rodríguez
Cristina
C
Vigil-Martín
Eduardo
E
Soto-Espinosa de los Monteros
Basilio
B
Pachón-Díaza
Jerónimo
J
D000328:Adult; D000368:Aged; D016470:Bacteremia / Q000175:diagnosis* / Q000453:epidemiology / Q000382:microbiology; D001769:Blood / Q000382:microbiology*; D015331:Cohort Studies; D048909:Diabetes Complications / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D004636:Emergency Service, Hospital / Q000706:statistics & numerical data*; D005260:Female; D016905:Gram-Negative Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D016908:Gram-Positive Bacterial Infections / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D017052:Hospital Mortality; D006785:Hospitals, University / Q000706:statistics & numerical data; D006801:Humans; D015994:Incidence; D015993:Life Tables; D008297:Male; D008875:Middle Aged; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D012307:Risk Factors; D018805:Sepsis / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D012772:Shock, Septic / Q000175:diagnosis / Q000453:epidemiology / Q000382:microbiology; D013030:Spain / Q000453:epidemiology; D016019:Survival Analysis; D014552:Urinary Tract Infections / Q000150:complications