Are white blood cell count, platelet count, erythrocyte sedimentation rate and C-reactive protein useful in the diagnosis of septicaemia and endocarditis?

In 851 predominantly adult patients with septicaemia or endocarditis data regarding white blood cell (WBC) count, platelet count, ESR and C-reactive protein (CRP) obtained within 3 days of admission were analyzed retrospectively. Among 232 patients with complete laboratory data none had the combination of normal ESR, negative CRP and lack of both leukocytosis and thrombocytopenia. CRP was positive (greater than 10 mg/l) in 93%, ESR was elevated (greater than 20 mm/h) in 90%, leukocytosis (WBC greater than 9 X 10(9)/l) was present in 60% and thrombocytopenia (platelets less than 150 X 10(9)/l) in 35% of the patients. Patients with pneumococcal infection had generally higher ESR and CRP values and WBC counts than patients with other infections.