[Nosocomial pneumonia in patients with haematological malignancies].

INTRODUCTION: Nosocomial pneumonia (NP) in patients with hematological malignancies (HM) has an attributable mortality over 90%. There are few studies that report the incidence of nosocomial infections in patients with HM.

OBJECTIVE: To describe the epidemiology and clinical course of NP in a cohort of patients with hematologic malignancies.

MATERIAL AND METHODS: Single-center study of patients with leukemia, lymphoma or multiple myeloma diagnosed with NP, hospitalized between January 2011 and December 2012.

RESULTS: One-hundred and five NP were recorded: 51 leukemias (48%) and 45 lymphomas (43%); 50 (48%) were in relapse or progression. Median days for NP development were 13 days (IQ 6-20). Sixty percent of the patients had severe neutropenia. The most frequent symptom was fever 73 (70%). CT scan showed infiltrates in 100% of cases; 45 (43%) with findings suggestive of invasive fungal infection. Seven (7%) had confirmed invasive fungal infection, possible 9 (9%) and 45 (43%) probable. There were 99 cultures taken, 30 blood cultures (67% were positive) and 31 sputum (71% positive). Sixty percent of Gramnegative bacteria were multi-drug resistant and 50% of the Grampositive, E. coli, 19 (30%) was the most frequent isolated, Aspergillus spp. was the third, but the one with the highest associated mortality. Attributable mortality for pneumonia was 50% and 73% in patients that required mechanical ventilation (p = 0.001).

CONCLUSIONS: We observed a high mortality rate in patients with HM and NP. Standardized diagnostic routes are needed for patients with HM with suspicion of pneumonia. Novel diagnostic techniques to enhance Aspergillus and respiratory viruses diagnosis should be introduced in this setting.