Viridans group streptococci bloodstream infections in neutropenic adult patients with hematologic malignancy: Single center experience

Viridans group streptococci bloodstream infections (VGS BSI) remain a significant cause of mortality and morbidity in patients with severe neutropenia. The goal of our study was to evaluate clinical course and microbiological susceptibility of VGS BSI at our center. Retrospective analysis of all microbiologically documented bloodstream infections caused by VGS during the 9-year time period (from January 2006 until December 2014) was carried out. Only patients with severe neutropenia (< 500/μL) were included in the study. Clinical outcome and microbiological susceptibility pattern of isolates were recorded. Fifty-one individual patients with episode of VGS BSI were identified. The most frequent agent was Streptococcus mitis (23/51 cases, 45.1%). 88.2% (45/51) of patients were on recommended ciprofloxacin prophylaxis. 20/51 (39.2%) of patients suffered from mucositis at the time of diagnosis (10 patients had oral mucositis, 2 patients had bowel mucositis, and 8 patients both). Twenty-six patients (51.0%) had clinically relevant lung damage caused by VGS BSI (i.e., acute lung injury or acute respiratory distress syndrome). Twenty-four (47.0%) patients presented with bilateral lung infiltrated upon chest imaging, and two (4.0%) patients had unilateral lung infiltrates. Three patients (5.9%) died due to VGS BSI until day 28 of observation. No difference in signs of shock syndrome was observed in the patients during transplantation procedures compared to patients without transplantation as well as in a group received previous high-dose chemotherapy with cytosinarabinoside or in patients with mucositis. Only 3/51 of isolates (5.9%) were resistant to penicillin. All isolates were susceptible to empirical treatment. While the penicillin resistance of VGS remains low in middle Europe, initial antibiotic therapy of febrile neutropenia are still effective in most cases. The mortality and complication rates of VGS BSI were comparable to other studies, and no specific risk factor of shock presence could be identified.