Haematological malignancy in the intensive care unit: microbiology results and mortality.

Background: Mortality prediction models of patients with a haematological malignancy admitted to an intensive care unit (ICU) do not include the presence of neutropenia and microbiology results. We performed a registry-based retrospective study of haematology patients admitted to the ICU to investigate the relation between neutropenia, microbiology results and outcome of these patients.

Methods: Neutropenia and microbiology culture results within 24 h before or after ICU admission of patients with a haematological malignancy admitted between 2004 and 2010 were described and analysed for association with 28-day mortality.

Results: We identified 234 individual patients with a current malignant haematological condition, of which 27% were neutropenic and 21% had a positive blood culture at admission. Most prevalent from blood cultured species were Escherichia coli and coagulase-negative staphylococci. The overall 28-day mortality was 38%. In patients with a positive blood culture but no neutropenia, 28-day mortality was 28% and in patients with neutropenia but without positive blood culture, it was 36%. The 28-day mortality of patients with both neutropenia and a positive blood culture was 55% with an adjusted (for APACHE-II score) hazard ratio (HR) of 1.8 (95%CI 1.0-3.4) compared to other hematologic patients admitted to the ICU.

Conclusion: In patients with haematological malignancy admitted to the ICU, culture results are diverse. The combination of neutropenia and positive blood culture is associated with increased 28-day mortality. We suggest this could be of additional value when assessing mortality risk in this patient group.