Predictive Value of a Quick Pitt Bacteremia Score for Prognosis of Patients with Bloodstream Infection Secondary to Urinary Tract Infection: A Retrospective Cohort Study

Figures & data

Table 1 Demographics and Clinical Characteristics of Patients with Bloodstream Infections Secondary to Urinary Tract Infections

Variable(s)	Survival (n=234)	Death (n=32)	Statistics* (F/Z/χ^2)		Good Prognosis (n=158)	Poor Prognosis (n=108)	Statistics* (F/Z/χ^2)
			Value	P-value			Value	P-value
Gender, n(%)			8.224	0.004			2.598	0.102
Female	140(59.8)	10(31.3)			96(60.8)	54(50.0)
Male	94(40.2)	22(68.7)			62(39.2)	54(50.0)
Admission to intensive care unit, n(%)	46(19.7)	32(100.0)	83.842	0.000	14(8.9)	64(59.3)	76.209	0.000
Comorbidity
Diabetes mellitus, n(%)	78(33.3)	12(37.5)	0.072	0.692	40(25.3)	50(46.3)	11.693	0.001
End-stage renal disease, n(%)	6(2.6)	0(0.0)	0.079	1.000	4(2.5)	2(1.9)	0.000	1.000
Charlson comorbidity index, median (IQR)	4(2,5)	6(4.5,7.5)	−5.315	0.000	3.0(2.0,5.0)	5.5(4.0,7.0)	−7.402	0.000
SBP ≤90mmHg or vasopressor used, n(%)	52(22.2)	24(75.0)	38.422	0.000	30(19.0)	46(42.6)	17.515	0.000
Respiratory status, n(%)			77.295	0.000			21.652	0.000
Respiratory rate <25 breaths/min	174(74.4)	12(37.5)			116(73.4)	70(64.8)
Respiratory rate ≥25 breaths/min	58(24.7)	8(25.0)			42(26.6)	24(22.2)
Mechanical ventilation	2(0.9)	12(37.5)			0(0.0)	14(13.0)
Type of urinary tract infection, n(%)			0.159	0.923			11.613	0.003
Symptomatic urinary tract infection	196(83.8)	26(81.3)			142(89.9)	80(74.1)
Asymptomatic bacteriuria	14(6.0)	2(6.2)			6(3.8)	10(9.3)
Other infections of the urinary tract	24(10.2)	4(12.5)			10(6.3)	18(16.6)
Site of acquisition, n(%)			9.752	0.008			26.591	0.000
Community-acquired	214(91.5)	24(75.0)			154(97.5)	84(77.8)
Hospital-acquired	18(7.6)	8(25.0)			4(2.5)	22(20.4)
Healthcare associated	2(0.9)	0(0.0)			0(0.0)	2(1.8)
Urinary tract obstruction, n(%)	116(49.6)	2(6.3)	19.687	0.000	84(53.2)	34(31.5)	11.357	0.001
Undergo urological surgery, n(%)	104(44.4)	0(0.0)	21.523	0.000	74(46.8)	30(27.8)	9.001	0.002
Altered mental status, n(%)	18(7.7)	24(75.0)	90.918	0.000	6(3.8)	36(33.3)	39.897	0.000
Initial application of carbapenem, n(%)	64(27.4)	14(43.8)	2.905	0.064	42(26.6)	36(33.3)	1.104	0.273
Initial appropriate antibiotic therapy, n(%)	214(91.5)	26(81.3)	2.267	0.103	146(92.4)	94(87.0)	1.532	0.206
Length of antibiotic treatment in day, mean ±SD	10.98±5.21	10.04±4.18	0.354	0.552	11.09±5.04	10.63±5.18	0.513	0.475
Days at home within 30 days, median (IQR)	18(15,21)	0(0,0)	−8.932	0.000	20(18,22)	8(0,15)	−13.828	0.000
Age in years, median (IQR)	65(56,71)	77(68,80)	−4.600	0.000	64(52,71)	69(64,77)	−3.157	0.000
qpitt, median (IQR)	0(0,1)	2(2,3)	−7.843	0.000	0(0,1)	1(0,2)	−4.509	0.000
Serum creatinine unit in μ mol/L, median (IQR)	84.2(67.3,119.3)	197.8(78.3,220.65)	−3.288	0.001	78.0(65.1,110.4)	110.7(70.7,207.0)	−3.743	0.000
Temperature unit in °C, median (IQR)	38.7(38.2,39,2)	36.9(36.7,38.8)	−4.051	0.000	38.7(38.2,39.3)	38.5(37.0,39.1)	−3.417	0.001
Peripheral WBC unit in 10^9/L, median (IQR)	11.66(9.10,16.75)	13.74(11.56,15.89)	−2.195	0.028	11.66(9.09,15.78)	12.95(9.79,17.89)	−1.724	0.085
Procalcitonin unit in ng/mL, median (IQR)	4.40(0.48,22.84)	28.52(2.85,62.60)	−3.038	0.002	1.56(0.42,16.38)	10.87(0.79,42.02)	−3.707	0.000
Heart rate in beats/min, mean ±SD	102.53±15.63	109.19±14.67	5.177	0.024	102.18±15.84	105.02±15.27	2.215	0.146
Peripheral blood platelet unit in 10^9/L, mean ±SD	175.10±77.60	172.18±113.94	0.035	0.852	179.71±76.35	167±90.73	1.411	0.236

Notes: *Classified variables, normal distribution continuous variables, and non-normal distribution continuous variables adopt χ² value, F value and Z value as statistics for comparison between groups, respectively.

Abbreviation: IQR, interquartile range.

Figure 1 The flow diagram about the source of the study population.

Table 2 Proportion of Different Pathogens in Blood Culture

Pathogens, n (%)	All Cases (n=266)	Survival (n=234)		Death (n=32)
		HLOS <14 Days (n=158)	HLOS ≥14 Days (n=76)
Gram-negative bacteria	206(77.44)	128(81.01)	60(78.95)	18(56.25)
Escherichia coli	144(69.90)	94(73.43)	40(66.67)	10(55.56)
Klebsiella spp.	38(18.45)	16(12.50)	16(26.67)	6(33.33)
Enterobacter cloacae	8(3.88)	6(4.69)	2(3.33)	0(0.00)
Others	16(7.77)	12(9.38)	2(3.33)	2(11.11)
Gram-positive bacteria	52(19.55)	28(17.72)	14(18.42)	10(31.25)
Staphylococcus	20(38.46)	12(42.86)	2(14.29)	6(60.00)
Enterococcus	18(34.62)	8(28.57)	8(57.14)	2(20.00)
Streptococcus	14(26.92)	8(28.57)	4(28.57)	2(20.00)
Fungi	8(3.01)	2(1.27)	2(2.63)	4(12.50)
Candida	8(100.00)	2(100.00)	(100.00)	4(100.00)

Table 3 Multivariable Logistic Regression Model Results for Independent Risk Factors of Poor Prognosis

Variable(s)	B	SE	Wals	P-value	OR	95% CI
						Lower	Upper
Charlson comorbidity index	0.411	0.071	33.68	0.000	1.509	1.313	1.734
qpitt	0.599	0.167	12.916	0.000	1.819	1.313	2.522
Temperature	−0.421	0.158	7.097	0.008	0.657	0.482	0.895

Table 4 Multivariable Logistic Regression Model Results for Independent Risk Factors of Death

Variable(s)	B	SE	Wals	P-value	OR	95% CI
						Lower	Upper
Charlson comorbidity index	0.570	0.146	15.128	0.000	1.768	1.327	2.356
qpitt	1.843	0.318	33.614	0.000	6.311	3.386	11.765
Temperature	−0.538	0.222	5.893	0.015	0.584	0.378	0.902

Table 5 Area Under ROC Curves for the Prediction of Poor Prognosis

Test Result Variable(s)	Areas	SE	P-value	95% CI
				Lower	Upper
Charlson comorbidity index	0.648	0.036	0.000	0.578	0.719
qpitt	0.765	0.030	0.000	0.707	0.823
Temperature	0.377	0.036	0.001	0.306	0.447

Table 6 Area Under ROC Curves for the Prediction of Death

Test Result Variable(s)	Areas	SE	P-value	95% CI
				Lower	Upper
Charlson comorbidity index	0.890	0.034	0.000	0.824	0.956
qpitt	0.787	0.037	0.000	0.714	0.861
Temperature	0.279	0.056	0.000	0.169	0.390

Figure 2 Receiver operator characteristic (ROC) curves of the independent risk factors for the prediction of poor prognosis.

Figure 3 Receiver operator characteristic (ROC) curves of the independent risk factors for the prediction of death.

Table 7 Stratified Analysis of Carbapenems as the Initial Therapy on the Prognosis

Variable(s)	qpitt ≥2 (n=54)		qpitt <2 (n=212)		All Cases (n=266)
	Poor Prognosis	Death	Poor Prognosis	Death	Poor Prognosis	Death
Used, n (%)	24(66.67)	12(33.33)	12(28.57)	2(4.76)	36(46.15)	72(38.29)
Unused, n (%)	18(100)	14(77.78)	54(31.76)	4(2.35)	14(17.95)	18(9.57)
P-value	0.005^C	0.002	0.689	0.340	0.306	0.056

Notes: ^cFisher’s exact test; “Used” indicates used carbapenems as the initial therapy; “Unused” indicates used other drugs (except carbapenems) as the initial therapy.