2717. The Impact of Pneumococcal Conjugate Vaccine in Nonbacteremic Pneumococcal Pneumonia Among Cancer Patients

Abstract

Abstract Background Invasive pneumococcal disease (IPD) and non-bacteremic pneumococcal pneumonia (NB-PNA) are associated with substantial morbidity and mortality in cancer patients. IPD incidence among cancer patients at MSKCC sharply declined after the introduction of routine childhood immunization with the 7-valent pneumococcal conjugate vaccine (PCV7) (1). An indirect effect of PCV on pneumococcal pneumonia incidence has also been reported (2, 3). The impact of PCV on the incidence of NB-PNA in patients with cancer has not been well studied. Methods Retrospective review of patients treated at MSKCC, 1993–2012. Unique patient visits (UPV) per year were defined as ≥1 inpatient or outpatient encounter within one calendar year. NB-PNA was defined as Isolation of Streptococcus pneumoniae from sputum or bronchoalveolar lavage (BAL); with associated symptoms (cough, sputum production, and/or fever) and radiographic findings compatible with pneumonia on chest radiograph or computerized chest tomography. NB-PNA incidence was calculated as number of NB-PNA cases per 1000 UPV. Three-time periods were examined: “before PCV7” (1993–2000), “after PCV7” (2001–2010), “after PCV13” (2011–2012). Results Of 323 NB-PNA cases, S. pneumoniae was isolated from BAL in 64 (20%) and sputum in 259 (80%). 182 (56%), 121 (37%), and 20 (7%) NB-PNA cases occurred “before PCV7,” “after PCV7,” and “after PCV13,” respectively. The incidence of NB-PNA was highest in patients with hematologic malignancies and in patients ≥65 years during all three periods (Table 1). NB-PNA incidence was lower “after PCV7” compared with “before PCV7” (0.47 vs. 0.13, P < 0.001). A non-statistically significant lower incidence of NB-PNA was noted “after PCV13” vs. “after PCV7” (0.13 vs. 0.09, P = 0.19). The highest decline of NB-PNA after PCV7 introduction was observed in patients ≥65 years (0.67 vs. 0.16, P < 0.001). Conclusion (1) The incidence of NB-PNA in adult cancer patient declined after PCV7 compared with before PCV7. (2) The reduction in NB-PNA was highest in patients ≥65 years suggesting an indirect effect from PCV7 childhood immunization. (3) A trend toward decreased incidence in NB-PNA was noted after PCV13; further surveillance is required to ascertain this trend. Disclosures All authors: No reported disclosures.