Although Staphylococcus haemolyticus (SH) represents an emerging etiology of methicillin-resistant (MR)
coagulase-negative staphylococcal nosocomial
bacteremia, little is known of clinical significance of this
infection. Thus, we performed case-control retrospective comparative analysis of MRSH
bacteremias (MRSHB), methicillin-resistant S. epidermidis
bacteremias (MRSEB), and methicillin-resistant S. aureus
bacteremias (MRSAB) in patients with
hematologic malignancies. Most patients in the three groups were neutropenic and had a
central venous catheter (CVC) in place at the onset of
bacteremia. However, MRSHB patients had a CVC in place prior to
bacteremia for a time significantly more prolonged than MRSEB and MRSAB ones (p<0.05).
Severe sepsis or
septic shock were more common in patients with MRSAB as compared with MRSHB (p=0.02). Nosocomial attributable mortality rate was very low in the 3 study groups (0 to 5.4%) and only two patients developed metastatic
infections. Overall, reduced susceptibility to
teicoplanin was observed in 19 (47.5%) MRSH and in 4 (10%) MRSE isolates. Resistance to
teicoplanin was observed in 6 isolates, all MRSH. Reduced susceptibility or resistance to
vancomycin was observed in 2 isolates, both MRSH. All MRSA isolates were susceptible to the
glycopeptides. Comparison between cases of
bacteremia in patients with MRSH isolates with reduced susceptibility to
teicoplanin and those with susceptible MRSH did not reveal significant differences in the clinical-microbiological response to
teicoplanin therapy and outcome. Our results seem to suggest that MRSHB in hematologic patients is associated with low morbidity and mortality rates. MRSH frequently shows a reduced susceptibility to
teicoplanin; however these in vitro data do not seem associated with an unfavorable clinical response to
teicoplanin therapy for MRSHB in patients with
hematologic malignancies.