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RESEARCH Open Access
Epidemiology of urinary tract infections and
antibiotics sensitivity among pregnant women
at Khartoum North Hospital
Hamdan Z Hamdan
1
, Abdel Haliem M Ziad
2
, Salah K Ali
3
, Ishag Adam
4*
Abstract
Background: Urinary tract infections (UTI) can lead to poor maternal and perinatal outcomes. Investigating
epidemiology of UTI and antibiotics sensitivity among pregnant women is fundamental for care-givers and health
planners.
Methods: A cross sectional study has been conducted at Khartoum north teaching hospital Antenatal Care Clinic
between February-June 2010, to investigate epidemiology of UTI and antibiotics resistance among pregnant
women. Structured questionnaires were used to gather data from pregnant women. UTI was diagnosed using mid
stream urine culture on standard culture media
Results: Out of 235 pregnant women included, 66 (28.0%) were symptomatic and 169 (71.9%) asymptomatic. the
prevalence of bacteriuria among symptomatic and asymptomatic pregnant women were (12.1%), and (14.7%)
respectively, with no significant difference between the two groups (P= 0.596), and the overall prevalence of UTI
was (14.0%). In multivariate analyses, age, gestational age, parity, and history of UTI in index pregnancy were not
associated with bacteriuria. Escherichia coli (42.4%) and S. aureus (39.3%) were the commonest isolated bacteria.
Four, 2, 2, 3, 4, 2 and 0 out of 14 E. coli isolates, showed resistance to amoxicillin, naladixic acid, nitrofurantoin,
ciprofloxacin, co-trimoxazole, amoxicillin/clavulanate and norfloxacin, respectively
Conclusion: Escherichia coli were the most prevalent causative organisms and showing multi drug resistance
pattern, asymptomatic bacteriuria is more prevalent than symptomatic among pregnant women. Urine culture for
screening and diagnosis purpose for all pregnant is recommended.
Introduction
Due to several anatomical and hormonal changes, preg-
nant women are more susceptible to develop Urinary
tract infections (UTI) [1]. UTI is a major health pro-
blem, it has been reported among 20% of the pregnant
women and it is the most common cause of admission
in obstetrical wards [2]. Symptomatic and asymptomatic
bacteriuria have been reported among 17.9% and 13.0%
pregnant women, respectively [3].
UTI (perhaps if untreated) can lead to serious obste-
tric complications, poor maternal and perinatal out-
comes e.g. intrauterine growth restriction, pre-
eclampsia, caesarean delivery and preterm deliveries [4].
Furthermore, it has been observed that asymptomatic
bacteriuria can lead to cystitis and pyelonephritis [5]
which can lead to acute respiratory distress, transient
renal failure, sepsis and shock during pregnancy [6].
Screening of pregnant women for UTI can minimize
these UTI associated complications [7]. Recently various
risk factors of UTI during pregnancy have been
reported; perhaps these are varied according the geogra-
phical, social and biological settings [8]. Escherichia coli-
with its multidrug resistant strains- has been found to
be the commonest cause of UTI among pregnant
women [9,10].
Investigating epidemiology of UTI (prevalence, risk
factors, bacterial isolates and antibiotic sensitivity) dur-
ing pregnancy is fundamental for care givers and health
planners to guide the expected interventions. While an
extensive published literature concerning UTI during
* Correspondence: ishagadam@hotmail.com
4
Faculty of Medicine, University of Khartoum, Khartoum, Sudan
Full list of author information is available at the end of the article
Hamdan et al.Annals of Clinical Microbiology and Antimicrobials 2011, 10:2
http://www.ann-clinmicrob.com/content/10/1/2
© 2011 Hamdan et al; licensee BioMed Central Ltd. This is an Open Access art icle distributed under the terms of the Creative
Commons Attri bution License (http://creativecommons.org /licenses/by/2.0), which permits unrestricte d use, distribution, and
reproductio n in any medium, provided the original work is properly cited.
pregnancy is available from other African countries [11],
there is no published data concerning UTI in pregnant
Sudanese women. Thus, this was the objective of this
study which has been conducted at the Antenatal Care
Clinic of Khartoum North hospital during the period of
February-June 2010.
Methods
A cross-sectional study has been conducted at Khartoum
North hospital Antenatal Care Clinic during the period
of February-June 2010. Consecutive pregnant women
who attended the Antenatal Care Clinic for the first time
was approached to participate in the study. Those with
known underline renal pathology or chronic renal disease
were excluded. After signing an informed consent, rele-
vant medical, obstetrical and socio-demographic charac-
teristics were gathered using pre-tested questionnaires.
Every woman was inquired for history suggestive of UTI
(urgency, frequency, loin pain etc) and history of using
antibiotics in the index pregnancy. Maternal weight,
height, and body mass index (BMI) was calculated as
weight in kilograms divided by height in meters squared.
Maternal haemoglobin was measured.
Mid stream urine samples were collected using sterile
container on the same day of enrolment. All the speci-
mens were analyzed within an hour of collection using
dipstick (Mannheim GmbH, Germany) following manu-
facturer’s instructions, then samples were analyzed for
culture and sensitivity. By Using standard quantitative
loop a 1 μland10μl were used to inoculate urine sam-
ple on Cysteine lactose electrolyte deficient Agar, Mac-
Conkey and Blood agar plates (OXOID-England). Plates
were incubated for 24 hr at 37°C. A diagnosis of UTI
was made when there were at least 10
5
colony forming
unit (CFU)/ml of urine. For contaminated specimens,
repeat culture was performed. Identification was done
using in house biochemical testing [12]. S. aureus was
identified by colonial morphology, gram positive stain-
ing, positive catalase activity, and positive coagulation
of citrated rabbit plasma (bioMe ‘rieux, Marcyl’Etoile,
France). Disc diffusion method was used to determine
susceptibility of the isolates as previously described
[13]. Individual colonies were suspended in normal sal-
ine to 0.5 McFarland and using sterile swabs the sus-
pensions were inoculated on Muller Hinton agar for
18-24 hr. E. coli ATCC 25922 was used as control
strains [14].
For gram-negative and positive bacteria the following
discs were tested: amoxicillin (25 μg), co-trimoxazole
(SXT) (1.25/23.75 μg), nitrofurantoin (300 μg), cipro-
floxacin (5 μg), nalidixic acid (30 μg), amoxicillin-clavu-
lanic acid (20 μg/10 μg), and norfloxacin (5 μg),
Symptomatic patients were given amoxicillin/clavulanate
as empirical treatment before culture results. All patients
were asked to come back for results after 2 days. Then
patients care at Antenatal Care Clinic has been continued
by her managing obstetrician in the particular unit.
Statistics
Data were entered in the computer using SPSS for win-
dows version13.0 and double checked before analysis.
Means and proportions of the socio-demographic and
obstetrical characteristics were calculated and compared
between the growth positive and negative groups using
student tand X
2
tests, respectively. Univariate and mul-
tivariateanalysiswereusedwith isolate positive group
as dependent variable and socio-demographic and obste-
trics variables as independent variables. Probability
values of <0.05 were considered as statistically signifi-
cant for all results.
Results
Two hundred and thirty-five pregnant women were
enrolled at the mean (SD) gestational age of 29 (7.9)
weeks. The mean (SD) of their age and parity were 27.5
(14.6) years and 2.6 (2.4), respectively. Out of 235 preg-
nant women, 66 (28.0%) had symptoms suggestive of
UTI. The prevalence of bacteriuria among symptomatic
and asymptomatic pregnant women were (12.1%), and
(14.7%), respectively, with no significant difference
between the two groups, and the overall prevalence of
UTI was (14.0%). Interestingly out of 33 who had signif-
icant bacteriuria, 14 (42.2%) had a history of UTI in
current pregnancy and received antibiotic for that
UTI. There was no significant difference in the socio-
demographic and clinical data between bacteriuric and
abacteriuric women, table 1.
Risk factors of urinary tract infections
None of the investigated factors (age, gestational age,
parity, symptoms and body mass index) were found as
risk factor for UTI in univariate and multivariate analy-
sis, table 2.
Bacterial isolates and their sensitivity
Eighteen (54.5%) and 15 (45.4%) of the 33 isolates were
gram negative and positive bacteria, respectively. E. coli
[14 (42.4%)] was the most predominant organism iso-
lated. Other isolates were S. aureus [13 (39.3%)], K.
pneumoniae [3 (9%)], group B streptococcus [2 (6%)] and
P. aeruginosa [1 (3%)].
Four, 2, 2, 3, 4, 2 and 0 out of 14 E. coli isolates,
showed resistance to amoxicillin, naladixic acid, nitro-
furantoin, ciprofloxacin, co-trimoxazole, amoxicillin/cla-
vulanate and norfloxacin, respectively. Thirteen S.
aureus isoltes showed resistant to amoxicillin (1), nor-
floxacin (3), co-trimoxazole (5), and naladixic acid (5).
K. pneumonia isolates (3) have resistance to amoxicillin
Hamdan et al.Annals of Clinical Microbiology and Antimicrobials 2011, 10:2
http://www.ann-clinmicrob.com/content/10/1/2
Page 2 of 5
(2), both naladixic acid and amoxicillin/clavulanate (1).
There was no resistance to co-trimoxazole, nitrofuran-
toin, norfloxacin and ciprofloxacin. One of the two
group B streptococcus isolates has resistance to naladixic
acid while sensitive to amoxicillin, nitrofurantoin, amox-
icillin/clavulanate, norfloxacin, co-trimoxazole and
ciprofloxacin. One P. aeruginosa isolate has resistance to
amoxicillin, nitrofurantoin, and co-trimoxazole, while
sensitive to naladixic acid, ciprofloxacin, amoxicillin/cla-
vulanate, norfloxacin.
Outof33whohadpositiveculturegrowth4hada
nitrate test positive, while 202 who had no growth in
the culture media only one had a false positive nitrate
test, this make the sensitivity and specificity of the
nitrate test versus culture growth as 12.1% and 99.5%
respectively.
Discussion
The main findings of this study were: the prevalence of
UTI among pregnant women was 14.0% - regardless to
the women’s age, parity and gestational age -and E. coli
was the commonest isolated organism with multi resis-
tance toward different antibiotics. The prevalence of
UTI among these women is similar to the prevalence of
UTI among pregnant women in the neighbor countries
e.g. 14.6% and 11.6% in Tanzania and Ethiopia [3,11].
Age, parity and gestational age were not associated
with UTI in this study as well as in neighboring Tanza-
nia [3]. However, maternal age, parity and morbid obe-
sity have been previously observed as risk factors for
UTI among pregnant women [8,15,16]. Likewise in this
study gestational age was not found as risk factor for
UTI among these women. Recently, it has been reported
that, UTI developed in third trimester [17]. Perhaps the
susceptibility of UTI during this period is due to uretral
dilatation which started as early as 6 week and reaching
the maximum during 22-24 weeks [9].
Other factors like low socio-economic status, sexual
activity, washing genitals precoitus, postcoitus, not void-
ing urine postcoitus and washing genitals from back to
front have observed as risk factors for UTI during preg-
nancy [15,18]. These factors have not been investigated
in the current study; otherwise the results would have
been changed. According to the traditions in central
Sudan, it might have been difficult to enquire about
washing genitalia and sexual activity; otherwise patients’
co-operation would be lost. Interestingly high prevalence
of urinary tract infection has been reported among
Sudanese females with genital mutilation [19], which
was widely practiced in Central Sudan [20].
In this study E. coli was the most common pathogen
(77.7% of the Gram-negative isolates, 42.4% of all iso-
late). This goes with results that obtained in Tanzania
where E. coli was 38% of the Gram-negative isolates and
25% of all isolate [21]. Likewise, many authors have the
same findings e.g. in Pakistan and India [8,22]. In this
study E. coli showed multidrug resistance mainly to
amoxicillin, co-trimoxazole and nitrofurantoin. In Africa
e.g. Tanzania, Kenya and Senegal it have been reported
that, E. coli in urinary isolates have a high antimicrobial
resistance pattern [3,10,23]. Likewise Gales et al and
Williams et al have reported high resistance of E. coli
towards different antimicrobials in Latin American and
Costa Rica, respectively [24,25]. Although, S. aureus was
known for years as rare urinary isolate [26], recently it
has been reported to be the most frequent pathogen
among pregnant women in Nigeria [27]. In this setting
it was found the second most prevalent bacteria, this is
in concert to the other previous observation [8].
In this study, 42.4% women who had positive isolate
received an antibiotic in the index pregnancy. It has
Table 1 Obstetrical characteristic between bacteriuric and
abacteriuric women in Khartoum north hospital, Sudan
Variables Women with
Bacteriuria
Women without
Bacteriuria
P
Age, years 25.7(5.3) 27.8(15.6) 0.438
Parity 2(2.1) 2.7(2.5) 0.132
Gestational Age,
weeks
29.6(6.9) 29.2(8.1) 0.783
Weight, Kg 65.8(9) 67.8(7.1) 0.245
Height, meter 1.6(6.) 1.6(6.) 0.007
Body mass index 24.8(2.7) 24.7(2.5) 0.845
History of UTI 14(42.4) 95(47) 0.623
History of
Antibiotic use
14(42.4) 89(44) 0.861
Hemoglobin, g/dl 9.7 (.9) 9.7 (0.9) 0.901
Dysuria 8(24.2) 58(28.7) 0.596
Urgency 1(3) 5(2.5) 1.000
Fever 33(100) 2(1) 1.000
Vomiting 33(100) 2(1) 1.000
Data were shown as mean (SD) or n (%) as applicable.
Table 2 Factors associated with UTI in pregnancy in
Khartoum North Hospital, Sudan using univariate and
multivariate analyses
Variables Univariate analysis Multivariate analysis
OR 95%CI POR 95%CI P
Age 0.9 0.8-1.0 0.2 0.9 0.8-1.0 0.2
Body mass index 1.0 0.8-1.1 0.8 1.0 0.8-1.2 0.4
Parity 0.8 0.7-1.0 0.1 0.9 0.7-1.1 0.4
Gestational age 1.0 0.9-1.0 0.7 1.0 0.9-1.0 0.9
Dysuria 0.7 0.3-1.8 0.5 0.8 0.3-2.5 0.8
Urgency 1.2 0.1-10.8 0.8 1.9 0.1-22.1 0.5
History of UTI 0.8 0.3-1.7 0.6 0.3 0.1-6.6 0.4
History of antibiotic use 0.9 0.4-1.9 0.8 3.0 0.1-64.9 0.4
Abbreviations: OR, Odds Ratio; CI, confidence interval.
Hamdan et al.Annals of Clinical Microbiology and Antimicrobials 2011, 10:2
http://www.ann-clinmicrob.com/content/10/1/2
Page 3 of 5
been shown that anti-microbial resistance to one drug
does not always correlate to the consumption of the
same drug or closely related drugs [28]. Inappropriate
antimicrobial use can lead to inadequate therapy and
contribute to further drug resistance [29]. The inap-
propriate use of antimicrobial in low income countries
is perhaps due to the lack of adequate knowledge about
drugs and non-availability or non-accessibility of guide-
lines for therapy [22] or to the availability of antimicro-
bials without prescription and perhaps it was prescribed
by non-skilled practitioners [30].
Conclusion
There was high prevalence of asymptomatic bacteriuria
among pregnant women in this setting regardless to
women’s age, parity and gestational age. E. coli with its
multi resistance towards antibiotics was the most com-
mon isolated organism. Thus urine culture should be
performed as screening and diagnostic tool of UTI in
pregnancy in this setting.
Ethics
This study was approved by Sudan Medical specializa-
tion Ethics Review Board, Sudan.
Acknowledgements
The authors are very grateful to all the patients for their co-operation.
Funding The study was funded by University of Khartoum, Khartoum,
Sudan
Author details
1
Faculty of Medicine, Al-Neelain University, Khartoum, Sudan.
2
Khartoum
North Hospital, Khartoum, Sudan.
3
National health laboratory, Khartoum,
Sudan.
4
Faculty of Medicine, University of Khartoum, Khartoum, Sudan.
Authors’contributions
HZA and AMZ carried out the study and participated in the statistical
analysis and procedures. IA coordinated and participated in the design of
the study, statistical analysis and the drafting of the manuscript. All the
authors read and approved the final version.
Competing interests
The authors declare that they have no competing interests.
Received: 14 November 2010 Accepted: 18 January 2011
Published: 18 January 2011
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doi:10.1186/1476-0711-10-2
Cite this article as: Hamdan et al.: Epidemiology of urinary tract
infections and antibiotics sensitivity among pregnant women
at Khartoum North Hospital. Annals of Clinical Microbiology and
Antimicrobials 2011 10:2.
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