Related Experiment Video
Updated: Mar 9, 2026
12:18
Subcutaneous Infection of Methicillin Resistant Staphylococcus Aureus MRSA
Published on: February 9, 2011
23.7K
Thrombocytopaenia during methicillin-sensitive Staphylococcus aureus bacteraemia.
E Forsblom1,2, I Tielinen3, E Ruotsalainen3
1Division of Infectious Diseases, Inflammation Center, University of Helsinki and Helsinki University Central Hospital, Helsinki, Finland. erik.forsblom@helsinki.fi.
Summary
Thrombocytopaenia, or low platelet count, in Staphylococcus aureus bacteraemia (SAB) patients is a significant indicator of poor outcomes, especially when persistent at day 7. This study highlights its prognostic value, excluding pre-existing conditions.
Area of Science:
- Infectious Diseases
- Hematology
- Clinical Medicine
Background:
- Prognostic impact of thrombocytopaenia in Staphylococcus aureus bacteraemia (SAB) is often assessed only at onset.
- Pre-bacteremic factors predisposing to thrombocytopaenia have not been adequately considered.
- This study focuses on the prognostic value of low thrombocyte count in SAB, excluding pre-bacteremic influences.
Purpose of the Study:
- To evaluate the prognostic impact of low thrombocyte count in patients with methicillin-sensitive SAB (MS-SAB).
- To assess thrombocytopaenia at different time points (blood culture, day 3, day 7) and its association with outcomes.
- To identify thrombocytopaenia as an independent prognostic marker in SAB, excluding confounding pre-bacteremic factors.
Main Methods:
- Multicenter retrospective analysis of 495 MS-SAB patients.
- Thrombocyte counts were measured at blood culture, day 3, and day 7.
- Exclusion of patients with chronic alcoholism, liver diseases, and hematologic malignancies to isolate SAB-specific effects.
Main Results:
- Thrombocytopaenia at blood culture and day 3 correlated with endocarditis and defervescence.
- Ninety-day mortality was significantly higher in patients with thrombocytopaenia at all measured time points (blood culture, day 3, day 7).
- Thrombocytopaenia at day 7 emerged as a significant independent negative prognostic marker (HR, 3.64; p<0.001), while at day 3 it showed a trend (HR, 1.83; p=0.05).
Conclusions:
- Thrombocytopaenia is a significant negative prognostic marker in MS-SAB, particularly when persistent.
- Thrombocytopaenia at day 7 is a strong independent predictor of poor outcomes in SAB.
- The timing of thrombocytopaenia assessment is crucial for its prognostic value in SAB.
