Severe pneumonia in critically ill cancer patients: clinical outcomes and a comparison between healthcare-associated pneumonia and community-acquired pneumonia

Abstract

Introduction. Severe pneumonia is a major source of mortality for cancer patients. Despite the knowledge on prognostic few studies thoroughly addressed the impact of CAP and HCAP classification or specific cancer-related factors in this population. OBJECTIVES. The aims of this study were to describe the characteristics and outcomes of cancer patients with severe pneumonia classified according to the ATS CAP/HCAP definitions. METHODS. A prospective cohort study performed from 2002 to 2011 at Instituto Nacional de Cancer and Hospital Sirio-Libanes, Brazil. Consecutive adult patients with cancer and presenting with pneumonia were enrolled. Demographic, clinical data were collected during the first day of ICU including CURB-65, SAPS II, SOFA score comorbidities, Performance Status, and cancer-related data.RESULTS A total of 268 patients were admitted in the ICU with pneumonia and were divided into CAP (n = 109/ 40.7 %) and HCAP (n = 159/59.3 %). There were 189 (70.5 %) patients with solid tumors and 81 (30.2 %) patients with hematological malignancies. 167 (62.3 %) patients had septic shock, 205 patients (76.5 %) were mechanically ventilated (MV) and 68 (25 %) patients received renal replacement therapy (RRT). ICU, hospital, 6 month mortality rates were 45.5, 67.9, 75 % respectively. When we compared CAP and HCAP, we observed that low-grade hematologic malignancy [CAP 10 (9.2 %) vs HCAP 31 (19.5 %) p 0.02] neutropenia at admission [5 (4.6 %) vs 27 (16.9 %) p 0.0019], steroids use before hospital admission [18 (16.5 %) vs 69 (43.4 %) p 0.0001] and noninvasive ventilation (NIV) [21 (19.26 %) vs 49 (30.81 %) p 0.04] were more frequent in HCAP. There were no significant differences between the two groups regarding age [CAP 68 (58-75.5) vs HCAP 64 (54-73) p 0.09], Charlson comorbidity index [3 (2-4) vs 3 (2-6) p 0.10], SOFA score D1 [7 (5-11) vs 7 (4-10) p 0.42] and hospital mortality [72 (66 %) vs 110 (69.2 %) p 0.59]. In univariate analysis, poor performance status (2-4) [Survivors 31 (36 %) vs Nonsurvivors 92 (50.5 %) p 0.03], septic shock at ICU admission [29 (33.7 %) vs 138 (75.8 %) p 0.0001], higher CURB-65 [31 (36 %) vs 92 (50.5 %) p 0.03], high levels of severity illness scores [SOFA in the first ICU day-6 (3-7.25) vs 8 (5-11) p\0.0001 and SAPS II-40.5 (33-50.25) vs 52 (42-65) p\0.0001], MV use [40 (46.5 %) vs 165 (90.6 %) p 0.0001], NIV failure [51 (59.3 %) vs 167 (91.76 %) p 0.0001] and RRT [4 (4.6 %) vs 64 (35.2 %) p 0.0001] were more frequent in non-survivors. Microbiological data was comparable between CAP and HCAP. CONCLUSIONS. Severe pneumonia in cancer patients is associated with an exceedingly high mortality. The classification based on ATS CAP/HCAP definitions does not help physicians to guide antimicrobial therapy or predict hospital mortality. Cancer patients are a distinct group of patients with pneumonia with specific characteristics predictors of outcome and mortality that may not be comparable to other groups of HCAP patients.