Clonal spread of carbapenem-resistant Acinetobacter baumannii in a neonatal intensive care unit

Accepted Manuscript Clonal spread of carbapenem-resistant Acinetobacter baumannii in neonatal intensive care unit Wirlaine Glauce Maciel, Kesia Esther da Silva, Julio Croda, Rodrigo Cayô, Ana Carolina Ramos, Romário Oliveira de Sales, Gleyce Hellen de Almeida de Souza, José Victor Bortolotto Bampi, Leticia Cristina Limiere, Junior César Casagrande, Ana Cristina Gales, Simone Simionatto PII:

S0195-6701(17)30581-9

DOI:

10.1016/j.jhin.2017.10.015

Reference:

YJHIN 5260

To appear in:

Journal of Hospital Infection

Received Date: 12 July 2017 Accepted Date: 20 October 2017

Please cite this article as: Maciel WG, da Silva KE, Croda J, Cayô R, Ramos AC, de Sales RO, de Souza GHdA, Bortolotto Bampi JV, Limiere LC, Casagrande JC, Gales AC, Simionatto S, Clonal spread of carbapenem-resistant Acinetobacter baumannii in neonatal intensive care unit, Journal of Hospital Infection (2017), doi: 10.1016/j.jhin.2017.10.015. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

ACCEPTED MANUSCRIPT 1

Clonal spread of carbapenem-resistant Acinetobacter baumannii in neonatal

2

intensive care unit

3

Wirlaine Glauce Maciela§, Kesia Esther da Silvaa§, Julio Crodaa,b,c, Rodrigo Cayôd, Ana

5

Carolina Ramosd, Romário Oliveira de Salesa, Gleyce Hellen de Almeida de Souzaa, José

6

Victor Bortolotto Bampia, Leticia Cristina Limierec, Junior César Casagrandec, Ana

7

Cristina Galesd, Simone Simionattoa*.

§

Both authors have equally contributed to this work.

M AN U

9

SC

8

RI PT

4

10 11

a

12

Dourados - UFGD, Dourados, Mato Grosso do Sul, Brazil.

13

b

14

c

15

Dourados, Mato Grosso do Sul, Brazil.

16

d

17

Universidade Federal de São Paulo - UNIFESP, São Paulo - SP, Brazil.

19 20

TE D

Fundação Osvaldo Cruz - FIOCRUZ, Campo Grande,Mato Grosso do Sul,Brazil.

Hospital Universitário de Dourados, Universidade Federal da Grande Dourados - UFGD,

EP

Laboratório ALERTA, Disciplina de Infectologia, Departamento de Medicina,

AC C

18

Laboratório de Pesquisa em Ciências da Saúde, Universidade Federal da Grande

Running title: Carbapenem-resistant A. baumannii in newborns.

21

*Corresponding author Address: Laboratório de Pesquisa em Ciências da

22

Saúde/Universidade Federal da Grande Dourados. Rodovia Dourados -Itahum, km 12,

23

Cidade Universitária, 79804970, Dourados, Mato Grosso do Sul, Brasil. Phone: +55 67

1

ACCEPTED MANUSCRIPT 24

3410-2225;

Mobile:

+55

25

[email protected].

67

99958-5355.

E-mail

address:

26

Abbreviations: NICU, neonatal intensive care units; CRAB, carbapenem-resistant A.

28

baumannii; NIU, neonatal intermediate unit; PCR, polymerase chain reaction; ST,

29

sequence typing; MLST, multilocus sequence typing.

AC C

EP

TE D

M AN U

SC

RI PT

27

2

ACCEPTED MANUSCRIPT SUMMARY

31

Acinetobacter baumannii has been frequently associated with colonization and/or

32

infection in neonatal intensive care units (NICU). In this study, we describe a clonal

33

spread of carbapenem-resistant A. baumannii (CRAB) isolates in a NICU. A total of 21

34

CRAB isolates were collected from premature newborns. Only polymyxin B was active

35

against such isolates. Nineteen CRAB isolates were clonally related (cluster C that

36

belonged to worldwide-disseminated ST1). All newborns had peripheral access and

37

previously received β-lactams therapy. The implementation of strict infection control

38

measures was of fundamental importance to eradicate the clonal type in the hospital.

M AN U

SC

RI PT

30

39

EP

TE D

Keywords: Colonization, multi-drug resistant, carbapenem, NICU.

AC C

40

3

ACCEPTED MANUSCRIPT INTRODUCTION

42

Acinetobacter baumannii is an opportunistic pathogen responsible for serious hospital

43

infections associated with high mortality and morbidity rates. The global emergence of

44

carbapenem-resistant A. baumannii (CRAB) has also become a major concern among

45

neonatal and paediatrics intensive care units (ICUs). Prematurity and low birth weight,

46

are considered the main risk factors for colonization and/or infection by CRAB. In

47

addition, the newborn’s innate defence mechanisms are immature to respond against

48

therapeutic interventions such as the use of invasive devices, antimicrobial broad-

49

spectrum therapy and vaccines, thus these factors may favour the acquisition of CRAB.1

M AN U

SC

RI PT

41

50

A. baumannii has developed several carbapenem resistance mechanisms, including low

52

permeability of the outer membrane, alteration of antibiotic binding sites,

53

overexpression of efflux pumps and production of carbapenemases. Metallo-β-

54

lactamases and carbapenem-hydrolysing class D β-lactamases are the main

55

mechanisms of resistance to carbapenems in A. baumannii. Most genes encoding

56

carbapenemases are generally inserted on composite transposons and/or integrons

57

carried by conjugative plasmids, which have facilitated the spread of these resistance

58

determinants.2 Carbapenem-resistant A. baumannii is typically associated with health

59

care–associated infections, leading to significantly higher morbidity, increased

60

mortality rates, longer hospitalization and excess health care costs.1,2 This study

61

describes the molecular epidemiology and risk factors associated with colonization of

62

CRAB in a neonatal intensive care units (NICU) and the control measures implemented

63

to contain the clonal spread.

AC C

EP

TE D

51

4

ACCEPTED MANUSCRIPT METHODS

65

Case-control study

66

A case-control study was conducted in the NICU and neonatal intermediate unit (NIU)

67

of a public teaching hospital located in the city of Dourados, MatoGrosso do Sul, a

68

Middle-West Brazilian state, between September 2013 and September 2015. The

69

facility provides 187 beds distributed among infirmaries, maternal and infant area and

70

the UTIs adult, paediatric, neonatal and Intermediate Care Units (ICU). Newborns

71

colonized with CRAB formed were selected as the cases and newborns colonized with

72

carbapenem-susceptible A. baumannii were selected as controls. For each case, one

73

control was selected during the same study period.

M AN U

SC

RI PT

64

74

Bacterial isolates

76

The CRAB isolates were recovered from rectal swabs and catheter tip cultures of 21

77

newborns. Colonization was defined as the isolation of a microorganism without

78

clinical manifestations of infection.3 The study was conducted with the approval of the

79

Research Ethics Committee from the Universidade Federal da Grande Dourados

80

(process number, 877.292/2014).

EP

AC C

81

TE D

75

82

Bacterial identification, susceptibility testing and phenotypic assays

83

Bacterial species identification was initially performed using the Vitek2® automated

84

system (bioMérieux, Hazelwood, MO) and confirmed by Matrix-Assisted Laser

85

Desorption Ionization-Time of Flight Mass Spectrometry (MALDI-TOF MS) using the

86

Microflex LT mass spectrometer and Biotyper 3.3 software (Bruker Daltonics, Bremen,

87

Germany), based on the manufacturer’s recommendation.4 Antimicrobial susceptibility 5

ACCEPTED MANUSCRIPT profile was determined using theVitek2® automated system (bioMérieux, Hazelwood,

89

MO) and interpreted based on the Clinical and Laboratory Standards Institute

90

guidelines, except for tigecycline that uses the breakpoints of European Committee on

91

Antimicrobial Susceptibility Testing. Screening for the production of carbapenemases

92

was performed by ertapenem hydrolysis assay using MALDI-TOF MS, as previously

93

published.4

RI PT

88

94

Polymerase Chain Reaction amplification

96

The presence of β-lactamase encoding genes (blaIMP-like, blaNDM-like, blaVIM-like, blaKPC-

97

like, blaOXA-23-like, blaOXA-24/40-like, blaOXA-48-like, blaOXA-51-like, blaOXA-58-like, blaOXA-143-

98

like) was evaluated using polymerase chain reaction (PCR) followed by DNA sequencing

99

using specific primers, as previously described.5 The ISAba1 upstream blaOXA-23-like and

M AN U

blaOXA-51-like genes were also subsequently evaluated using the PCR.

101

TE D

100

SC

95

Molecular typing

103

Genetic relationship was determined by pulsed-field gel electrophoresis (PFGE) using

104

the ApaI restriction enzyme.6 The restriction fragments were separated on a 1% (w/v)

105

agarose gel in 0.5% tris-borate-EDTA buffer in a CHEF-DR II electrophoresis system (Bio-

106

Rad Laboratories, Richmond, CA, USA) for 19 h at 14°C, using a pulse ramp rate

107

changing from 5 s to 60 s, at 6 V/cm. The restriction patterns were analyzed using the

108

BioNumerics software v. 3.0 (Applied Maths, Sint-Martens-Latem, Belgium). Percentage

109

similarity between the fingerprints was scored using the Dice coefficient. Sequence

110

Typing (ST) was characterized by multilocus sequence typing (MLST) based on the

AC C

EP

102

6

ACCEPTED MANUSCRIPT 111

Institut Pasteur scheme.5 Analyses of the allele sequences and ST were performed

112

through the A. baumannii MLST website (http://pubmlst.org/abaumannii/).

113

Statistical analysis

115

All clinical data were recorded into a Research Electronic Data Capture (Redcap)

116

database and SAS v.9.2 (SAS Institute, Cary, NC, USA), and analyzed using univariate

117

and multivariate models. Dichotomized and categorical data were analyzed using the

118

chi-square test or Fisher’s exact test. For continuous variables, the t-test or analyses of

119

variance (ANOVA) were used. Bivariate analyses were performed to verify the

120

associations between dependent and independent variables, and those reaching the

121

pre-specified level of significance (P < 0.05) were included in the multivariable analysis.

AC C

EP

TE D

M AN U

SC

RI PT

114

7

ACCEPTED MANUSCRIPT RESULTS

123

A total of 21 CRAB were isolated from rectal swabs and catheter tip cultures of

124

newborns hospitalized at the NICU and NIU. The patient’s age ranged from 2 to 13

125

days. There was no difference in age between cases and controls, median age 1 day

126

(IQR 1-1). The length of hospitalization varied from 6 to 61 days. All newborns were

127

considered premature (<37 weeks) and 15 of them had low birth weight (<2,500g)

128

(Table 1). In this study, newborns colonized by CRAB were exposed to previous use of

129

extended-spectrum penicillins (100%), cephalosporins (66.7%), and aminoglycosides

130

(80.9%).

M AN U

SC

RI PT

122

131

In the univariate analysis, CRAB colonization was associated with respiratory

133

syndromes (Respiratory Distress Syndrome, Transient Tachypnea), prematurity,

134

peripheral venous access and previous exposure to antibiotics, especially

135

cephalosporins (Supplementary Table I). A strong relationship between those variables

136

was observed, because all newborns were premature, had peripheral access, and

137

received β-lactams. Thus, no statistical significant results were observed in the

138

multivariate analysis (data not shown). During hospitalization, four patients, who were

139

colonized by CRAB, subsequently developed the infection by this pathogen and all of

140

them showed clinical improvement after receiving antimicrobial therapy (Table I).

141

However, 19.1% (n=4) and 4.7% (n=1) of cases and controls died during the

142

hospitalization, respectively. The cause of death in cases could not be attributed to

143

CRAB and might be related to unfavourable clinical conditions, such as gastroschisis,

144

neonatal anoxia, respiratory complications, congenital syphilis and heart diseases.

AC C

EP

TE D

132

145

8

ACCEPTED MANUSCRIPT 146

All CRAB isolates showed MIC50s, ≥ 8 mg/L-1for both imipenem and meropenem. They

147

were

148

piperacillin/tazobactam (MIC50; ≥ 128 mg/L-1), ceftazidime (MIC50; ≥ 32 mg/L-1),

149

ceftriaxone (MIC50; ≥ 32 mg/L-1), cefepime (MIC50; ≥ 16 mg/L-1), gentamicin (MIC50; ≥ 16

150

mg/L-1), amikacin (n=7/33.3%; MIC50; ≥ 32 mg/L-1), ciprofloxacin (MIC50; ≥ 4 mg/L-1),

151

and tigecycline (n=16/76.2%; MIC50; ≥ 8 mg/L-1). However, all CRAB isolates were

152

susceptible to colistin (MIC50;≤ 2 mg/L-1) and to a lesser extent, amikacin (n=11/52.4%;

153

MIC50;≤ 16 mg/L-1). All strains were phenotypically identified as carbapenemase

154

producers by the MALDI-TOF MS and carried ISAba1+blaOXA-23 and ISAba1+blaOXA-51-like

155

genes.

resistant

to

ampicillin/sulbactam

(MIC50;

≥

16

mg/L-1),

M AN U

SC

RI PT

also

156

PFGE analysis identified that 90.5% of CRAB isolates (n=19) were identical (100%

158

similarity) belonging to the designated cluster C, which was found in both ICUs (Figure

159

1). MLST typing showed that the majority of CRAB colonizing the premature newborns

160

in both neonatal ICUs belonged to ST1, which has been associated with the

161

international clone.

EP AC C

162

TE D

157

163

The infection control measures implemented, included surveillance cultures from all

164

neonates hospitalized for more than 48 hours in other wards or health institutions.

165

Individual use of medical equipment; isolation of patients colonized/infected by CRAB;

166

environmental cleaning of all surfaces including walls, floors, ceilings, windows,

167

furniture and medical equipment were intensified. Also, regular instruction meetings

168

were performed at the hospital wards. After implementing these measures, a

169

considerably reduction in the incidence of CRAB was observed (Supplementary Fig 1). 9

ACCEPTED MANUSCRIPT DISCUSSION

171

The present study observed that the CRAB colonization was associated with respiratory

172

syndromes, prematurity, peripheral access and previous exposure to antibiotics,

173

especially cephalosporins. These results are similar to previous reports that show prior

174

antimicrobial exposure contributed to the dissemination of carbapenem-resistant

175

Gram-negative bacilli in hospitalized patients.6 Prior studies also demonstrated

176

associations between carbapenem-resistance and length of exposure to central venous

177

catheters and assisted ventilation.7 To analyze the mechanisms of antimicrobial

178

resistance, phenotypic and molecular assays of CRAB isolates were performed. The

179

presence of ISAba1 upstream blaOXA-23 was responsible for the resistance to

180

carbapenems observed among the CRAB strains evaluated in the present study.2

M AN U

SC

RI PT

170

181

PFGE identified a predominant clonal type found in both ICUs. Newborns hospitalized

183

at the NICU were usually transferred to NIU when their clinical conditions significantly

184

improved to continue treatment. Thus, transfer of patients, indirect contact through

185

the hands of health care workers, and/or contaminated medical equipment might have

186

been responsible for the dissemination of the CRAB clone from one unit to another.

187

However, we failed to identify the common source of CRAB acquisition. MLST typing

188

showed that the majority of CRAB isolates belonged to ST1. In Latin America, OXA-23-

189

producing A. baumannii strains have been mainly related to ST1,8 ST259 and ST798,

190

with the last one being the most frequently found ST among Brazilian CRAB.

191

Interestingly, in our study, only two CRAB isolates belonged to ST79 and ST25, which

192

were both found in the NICU. The presence of ST25 previously reported in Bolivia9,

AC C

EP

TE D

182

10

ACCEPTED MANUSCRIPT 193

which borders the state of Mato Grosso do Sul, may explain the entry of this emerging

194

ST group in our state for the first time.

195

Carbapenem-resistant A. baumannii constitutes a potential source of transmission to

197

other patients and increased the risk of subsequent infection1,3,6. Our study showed

198

that following the initial detection of the CRAB, infection control measures have been

199

implemented and considerably reduction in the incidence of CRAB was observed

200

(Supplementary Fig 1).The main limitation of this study was the lack of relevant data

201

regarding systematic surveillance in the past, which made it difficult to determine if

202

there was an outbreak. Therefore, these results highlight the importance of the active

203

search for CRAB in newborns and importance of infection control measures to avoid

204

colonization and to prevent transmission of clones among patients.

AC C

EP

TE D

M AN U

SC

RI PT

196

11

ACCEPTED MANUSCRIPT Acknowledgements

206

Conflict of interest statement

207

None declared.

208

Financial support

209

This work was partially supported by the National Council for Science and

210

Technological Development (CNPq; grants 480949/2013-1) and by the Fundação de

211

Apoio ao Desenvolvimento do Ensino, Ciência e Tecnologia do Estado do Mato Grosso

212

do Sul (FUNDECT; grants 0212/12 and 0077/12). We are also grateful to the

213

Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) for providing

214

grants to W.G.M., K.E.S., A.C.R. and R.C. (PNPD 20131991), and to CNPq for providing

215

grant to A.C.G (Process number: 305535/2014-5).

AC C

EP

TE D

M AN U

SC

RI PT

205

12

ACCEPTED MANUSCRIPT 216

REFERENCES 1. Romanelli RM, Anchieta LM, Mourão MV, Campos FA, Loyola FC, Mourão PH, et

218

al. Risk factors and lethality of laboratory-confirmed bloodstream infection

219

caused by non-skin contaminant pathogens in neonates. J Pediatr (Rio J) 2013;

220

89:189-196.

221 222

RI PT

217

2. Howard A, O’Donoghue M, Feeney A, Sleator RD. Acinetobacter baumannii an emerging opportunistic pathogen. Virulence 2012; 3:243-250.

3. Jung JY, Park MS, Kim SE, Park BH, Son JY, Kim EY, et al. Risk factors for multi-

224

drug resistant Acinetobacter baumannii bacteremia in patients with

225

colonization in the intensive care unit. BMC Infec Dis. 2010; 10:228.

M AN U

SC

223

4. Carvalhaes CG, Cayô R, Assis DM, Martins ER, Juliano L, Juliano MA, et al.

227

Detection of SPM-1-producing Pseudomonas aeruginosa and class D β-

228

lactamase-producing Acinetobacter baumannii isolates by use of Liquid

229

Chromatography-Mass Spectrometry and Matrix-Assisted Laser Desorption

230

Ionization-Time of Flight Mass Spectrometry. J ClinMicrobiol 2013; 51:287-290.

TE D

226

5. Cardoso JP, Cayô R, Girardello R, Gales AC. Diversity of mechanisms conferring

232

resistance to β-lactams among OXA-23-producing Acinetobacter baumannii

234 235

AC C

233

EP

231

clones. Diagn Microbiol Infect Dis 2016;85:90-97.

6. Karaaslan A, Soysal A, Altinkanat Gelmez G, Kepenekli Kadayifci E, Söyletir G, Bakir M. Molecular characterization and risk factors for carbapenem-resistant

236

Gram-negative bacilli colonization in children: emergence of NDM-producing

237

Acinetobacter baumannii in a newborn intensive care unit in Turkey. J Hosp

238

Infect 2016; 92:67-72.

13

ACCEPTED MANUSCRIPT 239

7. Zarrilli R, Di Popolo A, Bagattini M , Giannouli M, Martino D, Barchitta M, et al.

240

Clonal spread and patient risk factors for acquisition of extensively drug-

241

resistant Acinetobacter baumannii in a neonatal intensive care unit in Italy.

242

Journal of Hospital Infection2012; 82: 260-265. 8. Sennati S, Villagran AL, Bartoloni A, Rossolini GM, Pallecchi L. OXA-23-producing

244

ST25 Acinetobacter baumannii: First report in Bolivia. J Global Antimicrob Resist

245

2016; 4:70-71.

RI PT

243

9. Chagas TP, Carvalho KR, de Oliveira Santos IC, Carvalho-Assef AP.C

247

haracterization of carbapenem-resistant Acinetobacter baumannii in Brazil

248

(2008-2011): countrywide spread of OXA-23-producing clones (CC15 and CC79).

249

Diagn Microbiol Infect Dis 2014; 79:468-472.

AC C

EP

TE D

M AN U

SC

246

14

ACCEPTED MANUSCRIPT Figure 1. Dendrogram displaying the genetic relatedness of 21 CRAB isolated from newborns

251

hospitalized in NICU and NIU. The 19 isolates containing 100% similarity were grouped under

252

the cluster C belonged to ST1.

AC C

EP

TE D

M AN U

SC

RI PT

250

15

ACCEPTED MANUSCRIPT

Table 1. Clinical characteristics of the babies colonized by CRAB isolates.

5 6 7 8* 9 10 11* 12 13 14 15

Treatment (dosage and days of therapy)

Outcome

OC

C

AMI(18mg), CEP(50mg), PNC(25mg)/13

Recovery

OC

N

AMI(18mg), PNC(25mg)/11

Recovery

OC

N

CAR(20mg), CEP(50mg), PNC(25mg)/20

Death

OC

N

AMI(15mg), PNC(25000UI)/1

Death

RI PT

Type birth

09/17/2013 09/23/2013

NICU

21

09/14/2013 09/23/2013

NIU

54

09/23/2013 09/30/2013

NICU

41

10/13/2013 10/21/2013

NICU

12

NICU

28

OC

C

AMI(15mg), PNC(25mg)/10

Recovery

NIU

17

OC

N

CAR(40mg), CEP(50mg), PNC(25mg)/13

Recovery

NICU

26

OC

N

AMI(18mg), PNC(25mg)/9

Recovery

10/13/2013 10/21/2013 11/09/2013 11/11/2013 11/07/2013 11/12/2013

SC

4*

Length Hospital Place prior to of hospital unit Admission stay (days)

M AN U

3

Date of isolation

11/07/2013 11/12/2013

NICU

19

OC

C

AMI(18mg), CEP(50mg), PNC(25mg)/12

Recovery

11/09/2013 11/12/2013

NIU

6

AH

N

AMI(18mg), PNC(25mg)/5

Recovery

11/09/2013 11/12/2013

NIU

7

OC

N

AMI(18mg), PNC(25mg)/8

Recovery

11/13/2013 11/19/2013

NICU

61

OC

C

11/15/2013 11/19/2013

NICU

59

OC

C

11/15/2013 11/19/2013

NICU

59

OC

C

12/04/2013 12/16/2013

NICU

16

AH

C

CEP(50mg), PNC(25mg)/10

Recovery

01/04/2014 01/07/2014

NIU

9

OC

C

CEP(50mg), PNC(25mg)/9

Recovery

TE D

2

Date of admission

EP

1*

Gestational Birth Clinical age (weeks), Weight isolates sex (g) Rectal 35, M 1,850 Swab Rectal 32, F 1,082 Swab Rectal 34, M 1,608 Swab Rectal 27, F 1,036 Swab Catheter 32, F 1,780 tip Rectal 31, F 1,664 Swab Rectal 31, F 1,470 Swab Rectal 31, M 1,790 Swab Rectal 35, M 2,630 Swab Rectal 33, M 2,608 Swab Rectal 31, F 698 Swab Rectal 29, F 1,294 Swab Rectal 29, M 1,320 Swab Catheter 36, M 3,192 tip Rectal 36, F 3,120 Swab

AC C

Patient identification

AMI(18mg), CAR(20mg), CEP(50mg), PNC(25mg)/18 AMI(18mg), CAR(20mg), CEP(50mg), PNC(25mg)/15 AMI(18mg), CEP(50mg), PNC(25mg)/11

Recovery Death Recovery

ACCEPTED MANUSCRIPT

1,650

17

32, M

1,830

18

33, M

1,990

19

30, M

1,180

20

34, F

964

21

32, M

1,724

Rectal Swab Rectal Swab Rectal Swab Catheter tip Rectal Swab Rectal Swab

01/06/2014 01/11/2014

NIU

26

OC

C

AMI(18mg), PNC(25mg)/7

Death

01/08/2014 01/15/2014

NIU

23

AH

N

CEP(50mg), PNC(25mg)/8

Recovery

01/06/2014 01/16/2014

NICU

49

01/29/2014 02/04/2014

NIU

52

01/25/2014 02/05/2014

NIU

47

04/20/2014 04/26/2014

NIU

10

RI PT

31, F

OC

C

AH

N

OC

C

OC

N

SC

16

AMI(18mg), CAR(20mg), CEP(50mg), PNC(25mg)/21 AMI(18mg), CEP(50mg), PNC(25mg)/19 AMI(18mg), CAR(20mg), CEP(50mg), PNC(25mg)/18 AMI(18mg), CEP(50mg), PNC(25mg)/8

Recovery Recovery Recovery Recovery

M AN U

*Patients who developed infection during hospitalization.Abbreviations:F, female; M, male; NICU, Neonatal Intensive Care Unit; NIU, Neonatal Intermediate Unit. OC, Obstetric Centre; AH, Another Hospital; C, Cesarean; N, Normal. AMI, Aminoglycoside; CAR, Carbapenems; CEP,

AC C

EP

TE D

Cephalosporins; PNC, Penicillin.

AC C

EP

TE D

M AN U

SC

RI PT

ACCEPTED MANUSCRIPT