Catheter-related blood stream infections (CRBSI) cause significant morbidity and mortality in patients with hematological malignancies. Previous studies have identified a predominance of gram-positive organisms causing CRBSI but they included both neutropenic and non-neutropenic patients with solid organ and hematological malignancies. The aim of our study was to evaluate the incidence and microbiological profile of CRBSIs in a specific cohort of patients with hematological malignancies in their non-neutropenic phase of illness.

A detailed retrospective review was done from January 2003 to December 2005 on all patients with hematological malignancies who had double-lumen non-antibiotic impregnated tunneled CVCs (Hickman catheters) inserted in our hospital to identify those fulfilling our criteria for CRBSI episodes.

Amongst 273 evaluable patients, 61 developed CRBSI on 70 occasions. In contrast to previous studies, there was a predominance of gram-negative infections (68%). The majority (73%) of initial CRBSI episodes required catheter removal within 7days of onset. Vancomycin and cefepime was the most common initial antibiotic regimen used.

This study highlights the predominance of gram-negative infections in our cohort of non-neutropenic patients with underlying hematological malignancies who had Hickman catheters whose lines were not salvageable in the majority of cases. Empiric monotherapy with an antimicrobial agent with broad spectrum gram-negative cover needs to be given upfront pending results of the nature and sensitivity of organisms identified.