Etiology of Community-Acquired Pneumonia Requiring Hospital Admission in Adults with and Without Cancers: A Single-Center Retrospective Study in China

Figures & data

Figure 1 Flow diagram of patients screening and recruitment.

Abbreviations: CAP, community-acquired pneumonia; HAP, hospital-acquired pneumonia; VAP, ventilator-associated pneumonia.

Figure 2 Prevalence of different types of cancers.

Figure 3 Seasonal distribution of Streptococcus pneumoniae among CAP patients with cancers and without cancers between September 2018 and August 2019.

Abbreviations: CAP, community-acquired pneumonia; NC, no cancer; C, cancer.

Figure 4 Seasonal distribution of Klebsiella pneumoniae among CAP patients with cancers and without cancers between September 2018 and August 2019.

Abbreviations: CAP, community-acquired pneumonia; NC, no cancer; C, cancer.

Figure 5 Seasonal distribution of predominant pathogens among overall CAP patients between September 2018 and August 2019.

Abbreviation: CAP, community-acquired pneumonia.

Table 1 Characteristics of CAP Patients with and Without Cancers (n = 417)

Variables	NC-CAP (n=268)	C-CAP (n=149)	P-value
Age (years), median (IQR)	60.0 (52.3–68.0)	61 (56.0–70.0)	0.001
Sex (male), n (%)	167(62.30)	126(84.56)	<0.001
Smoke	195(72.76)	103(69.13)	<0.001
Comorbidities, n (%)
Bronchiectasis	63(23.51)	5(3.36)	<0.001
COPD	42(15.67)	15(10.07)	0.110
ILD	18(6.72)	4(2.68)	0.078
Asthma	0	1(0.67)	0.179
Pulmonary embolism	3(1.12)	1(0.67)	0.653
Connective tissue diseases	30(11.19)	8(5.37)	0.048
Diabetes mellitus	26(9.70)	12(8.05)	0.575
Cardiovascular diseases	78(29.10)	48(32.21)	0.507
CNS diseases	42(15.67)	4(2.68)	<0.001
Renal diseases	5(1.87)	4(2.68)	0.581
Gastrointestinal diseases	18(6.72)	12(8.05)	0.613
Liver and gall disease	9(3.36)	8(5.37)	0.320
No comorbidities	70(26.12)	91(61.07)	<0.001
Clinical findings, n (%)
Fever	119(44.40)	34(22.82)	<0.001
Cough	234(87.31)	109(73.15)	<0.001
White sputum	104(38.81)	46(30.87)	0.106
Yellow sputum	106(39.55)	43(28.86)	0.029
Chest pain	28(10.45)	18(12.08)	0.610
Dyspnea	122(45.52)	52(34.09)	0.700
Hemoptysis	42(15.67)	26(17.45)	0.638
Fatigue	23(8.58)	12(8.05)	0.852
Nausea and vomiting	8(2.99)	1(0.67)	0.167
Complete blood count
(×10^9cell/L), median (IQR)
WBC	7.80 (5.61–10.77)	7.32 (5.40–10.23)	0.054
Neutrophil	5.40 (3.68–8.01)	5.01 (3.59–7.64)	0.044
Lymphocyte	1.30 (0.95–1.77)	1.23 (0.85–1.78)	0.313
Monocytes	0.55 (0.39–0.79)	0.51 (0.37–0.79)	0.473
Platelet	236.00 (172.00–295.75)	231.00 (173.00–307.00)	0.845
CRP (mg/L)
Known, n (%)	128(47.76)	58(38.93)	0.082
CRP > normal value, n (%)	93(34.70)	39(26.17)	0.073
PCT (ng/dL)
Known, n (%)	163(60.82)	80(53.69)	0.157
PCT > 0.5, n (%)	14(5.22)	14(9.40)	0.103
PCT > 0.5, median (IQR)	1.02 (0.73–7.10)	1.53 (0.78–3.24)	0.053
Respiratory failure, n (%)	60(22.39)	16(10.74)	0.003
Body temperature (°C), median (IQR)	37.0 (36.7–38.7)	36.8 (36.5–37.2)	<0.001

Abbreviations: SD, standard deviation; IOR, interquartile range; BALF, bronchoalveolar lavage fluid; COPD, chronic obstructive pulmonary disease; ILD, interstitial lung disease; CNS, central nervous system; WBC, white blood cell; CRP, C-reaction protein; PCT, procalcitonin; IQR, interquartile range; NC-CAP, no cancer-community-acquired pneumonia; C-CAP, cancer-community-acquired pneumonia.

Table 2 Etiologic Microorganisms of CAP Patients with and Without Cancers (n = 417)

	C-CAP (n=149)	NC-CAP (n=268)	P-value
Specimen (BALF), n (%)	98(65.78)	186(69.40)	0.446
Pathogen
Gram-positive pathogens, n (%)
MRS	25(16.78)	31(11.57)	0.135
Streptococcus pneumoniae	16(10.74)	22(8.21)	0.39
Staphylococcus aureus	2(1.34)	3(1.12)	0.354
A/C Streptococcus	1(0.67)	1(0.37)	1
Enterococcus faecalis	1(0.67)	0	0.357
MRSE	0	1(0.37)	1
Gram-negative pathogens, n (%)
Pseudomonas aeruginosa	15(10.07)	66(24.63)	<0.001
Haemophilus influenzae	28(18.80)	30(11.20)	0.032
Klebsiella pneumoniae	15(10.07)	19(7.09)	0.287
Escherichia coli	2(1.34)	0	0.057
Acinetobacter baumannii	2(1.34)	7(2.61)	0.181
Moraxella catarrhalis	1(0.67)	1(0.37)	1
Enterobacter aerogenes/cloacae	1(0.67)	4(1.50)	0.659
Stenomonas maltophilia	2(1.34)	5(1.87)	1
Atypical pathogens, n (%)
Legionella pneumophila	2(1.34)	1(0.37)	0.291
Mycoplasma pneumoniae	2(1.34)	22(8.21)	0.004
Fungi, n (%)
Filamentous fungi	6(4.03)	23(8.58)	0.08
Candida tropicalis	2(1.34)	2(7.46)	1
Torulopsis glabrata	2(1.34)	1(0.37)	0.291
Actinomyces	0	1(0.37)	1
Other pathogen, n (%)	4(2.68)	1(0.37)	0.057
Mixed pathogen, n (%)	20(13.42)	27(10.07)	0.3

Abbreviations: MRS, methicillin-resistant Staphylococci; BALF, bronchoalveolar lavage fluid; MRSE, methicillin-resistant Staphylococcus epidermidis; NC-CAP, no cancer-community-acquired pneumonia; C-CAP, cancer-community-acquired pneumonia.

Table 3 Overall Distribution of Pathogens as Isolated Alone and/or in Combination with Other Pathogens (Mixed Infection)

	C-CAP (n=149)	NC-CAP (n=268)	P-value
Specimen (BALF), n (%)	98(65.78)	186(69.40)	0.953
Pathogen
MRS	35(23.49)	42(15.68)	0.049
Streptococcus pneumoniae	24(16.11)	31(11.57)	0.189
Pseudomonas aeruginosa	17(11.41)	71(26.50)	<0.001
Haemophilus influenzae	33(22.15)	38(14.18)	0.038
Klebsiella pneumoniae	22(14.77)	25(9.33)	0.093
Mycoplasma pneumoniae	2(1.34)	22(8.21)	0.003
Filamentous fungi	7(4.70)	29(10.82)	0.033

Abbreviations: MRS, methicillin-resistant Staphylococcus; NC-CAP, no cancer-community-acquired pneumonia; C-CAP, cancer-community-acquired pneumonia.

Table 4 Univariate and Multivariate Logistic Regression Analyses of CAP Patients Without Cancers

Factors	MRS OR(95% CI)		Mycoplasma pneumoniae OR(95% CI)		Pseudomonas aeruginosa OR(95% CI)
	Univariate	Multivariate	Univariate	Multivariate	Univariate	Multivariate
Bronchiectasis	0.298(0.102–0.871)	0.258 (0.084–0.794)			8.470(4.509–15.908)	7.266(3.574–14.770)
CNS diseases	3.303(1.415–6.489)	2.511(1.130–5.580)
Connective tissue diseases
Sex
Fever			4.800 (1.716–13.430)	5.265 (1.759–15.763)
No comorbidities		0.360(0.146–0.888)	7.442(2.890–19.164)	4.093 (1.511–11.086)	0.316 (0.148–0.677)

Note: Blank cells indicate no statistical significance.

Abbreviations: CNS, central nervous system; OR, odds ratio; CI, confidence interval.

Table 5 Univariate and Multivariate Logistic Regression Analyses of CAP Patients Without Cancers

Factors	Filamentous Fungi OR(CI95%)		Haemophilus Influenzae
	Univariate	Multivariate	Univariate	Multivariate
Bronchiectasis
CNS diseases
Connective tissue diseases			2.521(1.030–6.171)	3.116 (1.147–8.464)
Sex
Fever
No comorbidities

Note: Blank cells indicate no statistical significance.

Abbreviations: CNS, central nervous system; OR, odds ratio; CI, confidence interval; CAP, community-acquired pneumonia.