The aim of this retrospective study was to evaluate the clinical effectiveness of meropenem in immunocompromised children. Between January 1998 and December 2002 in the hemato-oncological units of our hospital meropenem was used in 87 febrile events diagnosed in 55 patients, and 328 bacterial cultures were evaluated. Microorganisms were detected and identified in 64 of the 328 hemocultures; there was a predominance of gram-positive strains (67%). In 49.4% the infection was documented microbiologically. In 16 additional cases the infection was proven clinically and 32.2% of the episodes were considered to be fever of unknown origin. The success rate of the meropenem therapy-excluding the proven fungal or coagulase-negative Staphylococcus infections--was 72.9% and for the whole cohort 49.4%. The results demonstrate that meropenem is effective and well-tolerated when used for the treatment of neutropenic cancer children.