Vol.2, No.6, 625-629 (2010) Health
doi:10.4236/health.2010.26094
Copyright © 2010 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
Antibiotic sensitivity pattern of common bacterial
pathogens in NICU and neonatal ward in Hamedan
province of Iran
Alireza Monsef1, Fatemeh Eghbalian2*
1Pathology Department, Hamadan University of Medical Sciences, Hamadan, Iran
2Pediatric Department, Hamadan University of Medical Sciences, Hamadan, Iran; *Corresponding Author: eghbalian_fa@yahoo.com
Received 15 January 2010; revised 5 February 2010; accepted 8 February 2010.
ABSTRACT
Bacterial pathogens and drug resistance are
different in hospitals of each country. In this
study we determined bacterial path- ogens and
drug sensitivity in the neonatal ward and neo-
natal intensive care unit (NICU) in Ekbatan hos-
pital in Hamedan. This cross-sectional descrip-
tive study was done on 1150 hospitalized neo-
nates in neonatal and NICU wards of Ekbatan
hospital of the Hamadan university of medical
sciences from September 2004 to September
2006. Blood, cerebrospinal fluid (CSF), urine,
stool, eye excretion, synovial fluid, umbilical
secretion and ascitic fluid were evaluated. Posi-
tive cultures were evaluated for antibiotic re-
sistance with disk diffusion test methed. All of
the data in questionnaires was analyzed with
SPSS 13. Cultures including blood, urine, CSF ,
stool, eye excretion, synovial fluid, umbilical
secretion and ascitic fluid was done in 417
neonates (833 cultures). These cultures were
including: urine, 323 cases (38.8%) blood 293
cases (35.2%), CSF 180 cases (21.6%) , stool 17
cases (2%), eye secretion 16 cases (1.9%) and
other secretions (synovial, umbilical, etc) 4
cases (0.5%). The cultures were positive in 105
cases (25.2%). 60 male neonates (57.1%) and 45
female neonates (42.9%) were culture positive.
The most common microorganisms were E coli
66.7% (70 cases), Klebsiella 10.5% (11 cases).
Drug resistance was high in these microorgan-
isms. The most common microorganisms were
Ecoli and klebsiella. Drug resistance was high in
the isolated microorganisms.
Keywords: Drug Resistance; Neonate;
Bacterial Infections
1. INTRODUCTION
There has been high incidence of antimicrobial resis-
tance in bacterial infections in different parts of a coun-
try and also in any hospital [1-3]. Different mechanisms
are involved in drug resistance of microorganisms. It
may be genetic or non genetic in origin [4]. Widespread
use of broadspectrum antibiotics is the most important
factor, so antibiotic control policy has great importance
in drug resistance control [5]. The incidence of infec-
tions in hospitalized neonates is very high. After wide-
spread use of antibiotics in agriculture industry and
medicine from 1950, antibiotics resistance in common
pathogenic agents had increasingly emerged [6]. In de-
veloped countries constant investigation in this field had
done for identifying antibiotic resistance pattern. Re-
cently, the spectrum and resistance of the pathogenic
bacteria have constantly changed year after year because
of wide application of antimicrobial drugs [5-9]. It is
necessary to treat neonatal infections by empirical use of
antimicrobial drugs as soon as possible to reduce the
mortality of them. It is based on the knowledge of epi-
demiology of bacterial susceptibility pattern in each area
[6-15]. This study had done for identifying antimicrobial
susceptibility pattern in a western province of Iran in
neonatal ward to help the treatment of infected neonates.
2. MATERIAL AND METHOD
This cross-sectional descriptive study was done on 1150
hospitalized neonates in neonatal and neonatal intensive
care unit (NICU) wards of Ekbatan hospital of the
Hamadan University of Medical Sciences from Septem-
ber 2004 to September 2006. Approval from Hamadan
University of Medical Sciences was obtained prior the
study. All of the samples that had sent for bacteriological
analysis entered the study. They included blood, cere-
bro-spinal fluid (CSF), urine, stool, eye excretion, syno-
A. Monsef et al. / HEALTH 2 (2010) 625-629
Copyright © 2010 SciRes. Openly accessible at http://www.scirp.org/journal/HEALTH/
626
vial fluid, umbilical excretion and peritoneal fluid.
Urine samples in neonates had obtained by suprapubic
method. In case of bacterial growth, identification of the
bacteria had done and antibiogram by disc diffusion
method had performed (Karbibauer method, Padtan Teb
antibiotic disc Company).
The quality control modalities had done on the Na-
tional Reference Laboratory of Health standards. The
antibiotics susceptibility test results had entered the
questionnaires. The data had analyzed by SPSS software
(version 13).
3. RESULTS
A total of 1150 hospitalized neonates entered the study.
There were 417 cultured samples, 239 cases (56.1%)
were male and 183 cases (43.9%) were female.
The mean age of neonates was 11.3 ± 9.3 days, (1 to 30
days).
We found 833 cultures in 417 cases, they included:
urine culture 322 (38.7%), blood culture 293 (35.2%),
CSF culture 180 (21.6%), stool culture 17 (2%), eye
excretion 16 (1.9%), others (synovial fluid, cord excre-
tion …) 5 (0.6%).
In this study 25.5% of the cultures were positive and
74.8% were negative. 57.1% (60 neonates) of positive
cultures were male and remaining 42.9% (45 neonates)
were female.
Eye excretion was the most positive culture (81.2%).
(Table 1) Table 1 shows the results of cultures.
The most frequent isolated microorganisms were
E.coli 66.7% (70 cases) and Klebciella 10.5% (11 cases)
in decreasing order (Figure 1).
Table 2 shows the frequency of isolated bacteria in
the culture.
Table 3 shows the sensitivity and resistance pattern of
bacteria cultured in urine culture. Tables 4 and 5 reveal of
the bacterial susceptibility tests in the neonates.
4. DISCUSSION
Bacterial infection is still prevalent in newborns and it is
a major medical problem [1-3]. According to the euro-
pean countries reports, its prevalence had not changes in
previous half decade, whereas bacterial etiologic agents
had changed. From 1928 to 1932 beta hemolytic strep-
tococci with 38% prevalence and staphylococcus aurous
with 28% were the most frequent causes of septicemia,
although the former is not so prevalent yet [13-14]. In
the present study Escherichia coli (Ecoli) was 66.7% and
Klebciella was 10.5%, they were the more frequent bac-
teria isolated from urine, blood and eye excretion cul
tures. Ecoli was the most frequent isolated bacteria from
urine, eye excretion and blood cultures in an order of
Table 1. Abundance distribution of positive cultures according
to the source of culture in hospitalized neonates.
Culture results
Positive
(%) NO
Negative
(%) NO
Source of culture
70 (21.7) 253 (78.3) Urine (N = 323)
15 (5.1) 278 (94.9) Blood (N = 293)
-
180 (100) CSF (N = 180)
3 (17.6) 14(82.4) Stool (N = 17)
13(81.2) 3(18.8) Eye secretions (N = 16)
4(80) 1(20) Other body fluid (N = 5)
66.7%
10.5% 6.7% 6.7%
3.8% 2.9% 1.9% 1.0%
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
Ecoli
Clebsielleae
S.epidermidis
S.aurous
S.saprophyticus
Enterobacter
Streptococcus
Pseudomonas
Figure 1. Abundance distribution of isolated microorganisms
in culture positive newborns.
Table 2. Abundance distribution of isolated microorganisms
according to the source of culture in hospitalized neonates.
Source of culture
Isolated
microorganisms Urine
(N = 70)
Blood
(N = 15)
Stool
(N = 3)
Eye
secretions
(N = 13)
Other
body
fluid
(N=4)
E.coli (%77.1)54 (%53.3)8 - (46.2%)6(50%)2
Klebsiella (%12.9)9 (%6.7)1 (33.3)1 - -
S.Saprophyticus (%5.7)4 - - - -
Enterobacter (%1.4)1 (%6.7)1 (33.3)1 -
S.Aurous (%2.9)2 (%6.7)1 - (%23.1)3(%25)1
S.Epidermidis - (%26.7)4 - (%23.1)3-
pseudomonas - - (33.3)1 -
Streptocucus - - - (%7.7)1(%25)1
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77.1%, 46.2% and 53.6% respectively. These findings
are consistent with the results of Eghbalian et al. study
[15]. Yalaz et al. in Turkey studied 909 newborns, 9.1%
of them had sepsis, the isolated bacteria were: coagulase
negative staphylococcus 31.3%, fungi 19.2%, staphylo-
coccus aurous 13%, Klebsiella Pneumonia 10.5% in
decreasing order [11].
Another study of Aurangzeb et al. at 2003 revealed
112 hospitalized newborns as sepsis, 67% had positive
blood culture and E.coli was the most frequent cause
with 77.1% frequency [12]. Bacterial meningitis has
various ethologic factors and majority of authors believe
that its agents varies according to age and geographic
distribution [1,3,15,16]. In present study we did not
found any positive cerebrospinal fluid culture in the
newborns. In our study E.coli, the most prevalent iso-
lated microorganism, shows high degree resistance to
cephalosporins. It showed 75.9% resistance in urine cul-
ture to Ceftriaxone, and 60% to Ceftizoxime (Table 3).
When we separated the E.coli from the blood and eye
excretion cultures, most of them were resistant to Cepha-
losporins specially to Ceftriaxone. Also E.coli was resis-
tant to majority of aminoglycozid antibiotics including
Amikacin, Gentamycin and Tobramycin. (Tables 4, 5) In
our study the resistance of E.coli to the Ciprofloxacin,
Nalidixic acid, Nitrofurantoin and Cotrimoxazol were in
a decreasing order (Tables 3, 4, 5) .These findings are
consistent with the results of a similar study [15]. Au-
rangzeb et al. in a similar study showed high degree re-
sistance of gram negative bacteria to conventional anti-
biotics: 79.3% to Ampicillin, 74.6% to Amoxicillin,
71.6% to Ceftazidime, 50.2% to Cefotaxime, 43.2% to
Gentamycin, 34.3 to Tobramycin, 23.6% to Imipenem,
22.3% to Amikacin and 11.9% to Ciprofloxacin [12].
Also staphylococcus aurous showed 75% resistance to
Ampicillin [12]. The present study revealed high per-
centage resistance of staphylococcus aurous to cepha-
losporin and other broad spectrum antibiotics.
Table 3. Percentage of sensitivity and resistance of isolated bacteria from positive urine culture in hospitalized neonates.
Microorganisms
E.coli Clebsiellea S.Saprophyticus Enterobacter S.Aurous Antibiotic
Sensitive Resistance SencetiveResistanceSencetiveResistanceSencetive Resistance Sencetive Resistance
Ceftriaxon
7 (%1/24) 22 (%9/75) 0 6 (%100)--- --- --- --- --- ---
Amikacin
15 (%9/34) 28 (%1/65) 2 (%3/33)4 (%7/66)0 3 (%100)1 (%100) 0 0 1 (%100)
Ciprofloxacin
27 (%8/81) 6 (%2/18) 6 (%100)0 1 (%100)0 1 (%100) 0 --- ---
Jentamycin
11 (%6/25) 32 (%4/74) 2 (%25) 6 (%75) 0 3 (%100)0 1 (%100) 1 (%100) 0
Tobramycin
2 (%3/14) 12 (%7/85) 0 1 (%100)--- --- --- --- --- ---
Nalidixic acid
33 (%75) 11 (%25) 8 (%9/88)1 (%1/11)2 (%7/88)1 (%3/33)1 (%100) 0 --- ---
Trimetoprim
6 (%40) 9 (%60) 0 2 (%100)--- --- --- --- --- ---
Ceftixocim
14 (%40) 21 (%60) 0 6 (%100)0 1 (%100)1 (%100) 0 1 (%100) 0
Nitrofurantoin
26 (%7/66) 13 (%3/33) 2 (%6/28)5 (%4/71)1 (%3/33)2 (%7/66)1 (%100) 0 0 1 (%100)
Cotrimoxazol
16 (%64) 9 (%36) 4 (%7/66)2 (%3/33)2 (%100)
0 --- --- --- ---
Cefotacxim
10 (%40) 15 (%60) 0 4 (%100)1 )50(%1 (%50) 0 1 (%100) --- ---
Vanc omyc ine
--- --- --- --- 0 2 (%100)--- --- --- ---
Cephalexin
5 (%50) 5 (%50) 0 1 (%100)0 2 (%100)--- --- 0 1 (%100)
Cephtazidim
0 4 (%100) --- --- 1 (%100)0 --- --- --- ---
Ampicillin
2 (%40) 3 (%60) --- --- --- --- 0 1 (%100) --- ---
Cephalotin
4 (%100) 0 --- --- --- --- --- --- --- ---
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Table 4. Percentage of sensitivity and resistance of isolated bacteria from positive blood culture in hospitalized neonates.
Microorganisms
E.coli klebsiellea S.Epidermidis Enterobacter S.Aurous Antibiotic
Sensitive Resistance SencetiveResistanceSencetiveResistanceSencetive Resistance Sencetive Resistance
Ceftriaxon
0 4 (%100) --- --- 1 (%100)0 --- --- --- ---
Amikacin
3 (%50) 3 (%50) 0 1 (%100)1 (%100)0 1 (%100) 0 --- ---
Ciprofloxacin
5 (%100) 0 --- --- 1 (%100)0 1 (%100) 0 --- ---
Gentamycin
2 (%40) 3 (%60) 0 1 (%100)1 (%100)0 1 (%100) 0 0 1 (%100)
Nalidixic acid
3 (%75) 1 (%25) 1 (%100)0 --- --- 1 (%100) 0 --- ---
Ceftizoxime
2 (%50) 2 (%50) 1 (%100)0 1 (%50) 1 (%50) --- --- --- ---
Tetracyclin
5 (%71/4) 2 (%28/6) 0 1 (%100)--- --- 1 (%100) 0 --- ---
Nitrofurantoin
4 (%57/1) 3 (%42/9) 0 1 (%100)1 (%100)0 0 1 (%100) --- ---
Cotrimoxazol
2 (%50) 2 (%50) 1 (%100)0 --- --- 0 1 (%100) --- ---
Cloxacillin
--- --- --- --- 0 3 (%100)
--- --- --- ---
Cefotacxim
2 (%40) 3 (%6) 0 1 (%100)1 (%100)0 --- --- 0 1 (%100)
Vanc omyc ine
--- --- --- --- 4 (%100)0 --- --- --- ---
Table 5. Percentage of sensitivity and resistance of isolated bacteria from positive eye excretions culture in hospitalized neonates.
Microorganisms
E.coli S.Aurous S.Epidermidis Streptocucus Antibiotic
Sencetive Resistance Sencetive Resistance Sencetive Resistance Sencetive Resistance
Ceftriaxon
0 (%100) 4 0 (%100) 1 --- --- --- ---
Amikacin
(%60) 3 (%40) 2 (%50) 1 (%50) 1 0 (%100) 1 0 (%100) 1
Ciprofloxacin
(%33/3) 1 (%66/7) 2 --- --- 0 (%100) 1 --- ---
Gentamycin
(%33/3) 1 (%66/7) 2 (%100) 1 0 0 (%100) 1 0 (%100) 1
Ceftixocim
(%25) 1 (%75) 3 0 (%100) 1 (%50) 1 (%50) 1 --- ---
Tetracyclin
(%100) 3 0 --- --- --- --- --- ---
Amoxicillin
--- --- 0 (%100) 1 (%100) 1 0 --- ---
Cloxacillin
(%100) 1 0 0 (%100) 1 0 (%100) 2 --- ---
Erythromycin
--- --- 0 (%100) 2 (%50) 1 (%50) 1 --- ---
Cefotacxim
(%25) 1 (%75) 3 (%50) 1 (%50) 1 0 (%100) 1 (%100) 1 0
vancomycin
--- --- (%100) 1 0 (%100) 3 0 (%100) 1 0
Cephalexin
0 (%100) 1
(%50) 1 (%50) 1 (%100) 1 0 --- ---
Ampicillin
0 (%100) 2 0 (%100) 1 (%50) 1 --- ---
Chloramphenicol
--- --- (%100) 1 0 --- --- --- ---
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5. CONCLUSIONS
Our experience showed that gram-negative bacteria were
the most prevalent cause of infections in neonates in our
hospital. E.coli and Klebsiella were the most frequent
bacteria and majority of them were resistant to broad
spectrum antibiotics. Drug resistance to conventional
antibiotics is a common problem and it grows readily.
Antimicrobials must be administered conservatively
according to epidemiologic studies in the region, with
confirmed indications, and based on the results of sus-
ceptibility tests.
6. ACKNOWLEDGEMENTS
The authors would like to acknowledge the office of Vice chancellor
for research of Hamadan University of Medical Sciences for financial
support of this study. Also we would like to thank Mr. Mani Kashani K
for his assistance in statistical analysis, Dr Lak-Zadeh M and staff of
neonatal ward for their contribution and collaboration.
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