Shapiro Rule (Who Needs a Blood Culture?)

Helps decide whether an adult emergency-department patient with suspected infection needs a blood culture, combining major and minor findings into a yes/no recommendation and a low/intermediate/high bacteremia likelihood.

Fever / temperature category

Indwelling vascular catheter present (major, +2)

Clinically suspected endocarditis (major, +3)

Age greater than 65 years (minor, +1)

Chills / rigors (minor, +1)

Vomiting (minor, +1)

Hypotension (systolic BP less than 90 mmHg) (minor, +1)

Neutrophil percentage greater than 80% (minor, +1)

WBC greater than 18,000 cells/mm3 (minor, +1)

Bands greater than 5% (minor, +1)

Platelets less than 150,000 cells/mm3 (minor, +1)

Creatinine greater than 2.0 mg/dL (minor, +1)