Community-Acquired Urinary Tract t Infection

Community-Acquired Urinary Tract t Infection
Etiology and Bacterial Susceptibility)

Dr. Nawal S Faris
Department of Allied medical sciences /Zarqa University)

ABSTRACT
Background: Urinary tract infections (UTI) are one of the most common infectious
diseases diagnosed. UTI account for a large proportion of antibacterial drug
consumption and have large socio-economic impacts. Since the majority of the
treatments begins or is done completely empirically, the knowledge of the organisms,
their epidemiological characteristics and their antibacterial susceptibility that may vary
with time is mandatory.
Objectives: The aim of this study was to report the prevalence of uropathogens and
their antibiotic susceptibility of the community acquired UTI diagnosed in our
institution and to provide a national data.
Methods: We analyzed retrospectively the results of urine cultures of 416 patients that
had community acquired urinary tract infection in the year of 2011.
Results: The most commonly isolated organism was Escherichia coli (70%). β-
Hemolytic Streptococuus group B (8%) and Klebsiella sp (7.6%) were reported as the
next most common organisms. Of all bacteria isolated from community acquired UTI,
only 21% were sensitive to ampicillin, 23% to ciproflaxacin and 18% to
cotrimoxazole. The highest levels of susceptibility were to cephalothin (81%),
Gentamicin (40 %), Augmentin (33%),
Norfloxacin (28%), Nitrofurantion (23%), Lefloxacin (21%), Nalidixic acid (16%),
Imipenem (14%).
Conclusion: Gram-negative agents are the most common cause of UTI. Cephalothin
remains the choice among the orally administered antibiotics, followed by
Gentamicin, Augmentin. For severe disease causes by Escherichia coli which is the
most common cause community acquired UTI that require antibiotics such as
nitrofurantion, followed by third generation cephalosporins, which were the most
effective.
Keywords: Urinary tract; Infection; Community; Bacteria; Antibiotic; Susceptibility.
INTRODUCTION
Community-acquired urinary tract infections (UTIs) are among the most common
bacterial infections in women. Therapy for these infections is usually begun before
results of microbiological tests are known. Furthermore, in women with acute
uncomplicated cystitis, empirical therapy without a pretherapy urine culture is often
used. The rationale for this approach is based on the highly predictable spectrum of
etiologic agents causing UTI and their antimicrobial resistance patterns.
The aim of this study was to report the information about the uropathogens and their
antibiotic susceptibility of the community acquired UTI diagnosed in our institution
and to provide a recent national data.
METHODS
We analyzed the results of urine cultures of 419 patients that had community acquired
urinary tract infection [³ 105 colony-forming units (CFU/mL)11] and had urine
sampled in the Central Laboratory of the Ministry of Health in Amman the capital of
Jordan, January to June of 2011.
RESULTS:
The results of urine cultures of 419 patients that had community acquired urinary
tract infection. The prevalence of the community acquired urinary tract infection in
female almost six times the men (86% vs. 14%). Table 1
Table 1: The prevalence of male vs. female.
NO of malN e 0 months of female
January 32 1
February 27 3
March 27 7
April 26 5
May 30 10
June 35 5
July 34 5
August 21 2
September 38 8
October 36 4
November 19 4
December 32 5
Total 357 59
Percentage 86% 14%
Pathogens
The most commonly isolated organism was Escherichia coli (70%), β-Hemolytic
Streptococuus group B (8%) and Klebsiella sp (7.6%) were reported as the next most
common organisms. The others bacteria are summarized in Table 2.
Table 2: Micro-organism isolated in urine.
Agents Number (416) %
E.coli 292 70.2
Streptococcus group B 34 8.2
Klebsiella sp 32 7.7
Enterococcus sp 15 3.6
Staphcoagulase negative 14 3.4
Acinetobacter sp 10 2.4
Proteus sp 6 1.4
S. aureus 4 0.96
Pseudomonas sp 4 0.96
Enterobacter 3 0.7
Morganella sp 1 0.2
Providencia sp 1 0.2
Bacterial susceptibility
The comparison of the susceptibility pattern of organisms to various antimicrobial
agents from all the specimens was shown in Table 3. Escherichia. coli showed high
susceptibility to nitrofurantoin (87%) then gentamicin (74%); to ceftaxime (72%);
fluoroquinolones: norfloxacin (55%), ciprofloxacin (38%) and levofloxacin (48%);
second and third generation cephalosporins and imipenem. There was a low
susceptibility pattern of E. coli to ampicillin (29%), imipenem (14%) and amikacin
(6%).
Table 3: Antibiotic susceptibility of uropathogens.
β- Hemolytic Streptococuus group B was highly susceptible to ampicillin (82%) and
augmentin (26%); to cephalothin (26%); to cephalosporin: cefoxitin (21%).
Nevertheless, there was a decreased susceptibility to norfloxacin (0%), ciprofloxacin (0%),
cotrimoxazole (6%) and leftoxacin (3%).
Klebsiella sp was highly susceptible to aminoglycosides: gentamicin (40%) and
amikacin (84%); to cephalosporins: cefotaxime (43%) and cephalothin (44%).
Nevertheless, there was a decreased susceptibility to nitrofurantoin (23%), norfloxacin
(28%), ciprofloxacin (11%), cotrimoxazole (18%) and ampicillin (21%). (Table 3)
Percentage of susceptible micro-organisms
Of all bacteria isolated from community acquired urinary tract infection, only 39%
were sensitive to ampicillin, 44% to cefalothin and 18% to cotrimoxazole. The highest
levels of susceptibility were to ceftaximne (43%), gentamicin (40%), levofloxacin
(21%), nitrofurantoin (23%), norfloxacin (28%) and ciprofloxacin (11%). (Table 3)
General β- Hemolytic Klebsiella sp(%) al (%)
Streptococuus
group B (%)
Drugs E.coli (%)
Gentamicin 74 12 75 40
Cefotaxime 72 21 66 43
Nitrofurantion 87 20 56 23
Norfloxacin 55 0 62 28
Leftoxacine 48 3 18 21
Ciprofloxacin 38 0 24 11
Augmentin 38 26 25 33
Cephalothin 36 26 44 44
Cotrimoxazole 36 6 56 18
Nalidixic acid 34 0 53 13
Ampicillin 29 82 0 39
Imipenem 14 – 16 14
Amikacin 5 – 4 4
Ceftazidime 6 – 3 3
Cephradin 9 4 6 5
DISCUSSION
Urinary tract infection occurs according to the demographic data, it is more frequent
in woman.
The present study is retrospective, using the results of our routine diagnostic and
susceptibility analysis. These data are from the Central Laboratory of the Ministry of
Health in Amman the capital of Jordan , the patients are screened in the primary and
secondary level of healthy system and prone to associated conditions and diseases.
These factors may influence the patterns of the data herein presented. We are
concerned about the necessity of periodical re-evaluation of bacterial etiology and
antibiotic resistance in each health unit and of a national surveillance to avoid the rise
of the antimicrobial resistance.
In the community, it is important to guide the general practitioners that generally treat
empirically the UTI, for what they need to be aware of the locally prevalent strains and
their sensitivity pattern. Geographic variations in pathogen occurrence and
susceptibility profiles require frequent monitoring to provide information to guide the
therapeutic options. Unfortunately, there is few studies published on the prevalence of
strains and their antimicrobial susceptibilities in different places in the world .
We found that E. coli is the predominant bacterium in urine samples, corresponding to
58% of the cases. This is in accordance with previous studies13-15, however in a study
from Norway16 E. coli caused 70% of UTI in outpatients compared to 58% in the
present study. A lower proportion of UTI was caused by β- Hemolytic Streptococuus
group B (8%) and Klebsiella sp .
E. coli exhibited resistance to the commonly used antibiotics, and the most effective
in-vitro agents were found to be aminoglycosides: nitrofurantion (87%) and
gentamicin (74%) among the injectables; and fluoroquinolonas: norfloxacin (55%),
ciprofloxacin (38%) and levofloxacin (48%) among the orally administered ones.
Other useful oral antibiotic is augmintin (38%). The organisms showed resistance to
common used urinary antibiotics like ampicillin (17%), amikacin (8%) and
cephradin(9%), in disagreement with data published by others13,17,18.
In summary, nitrofurantion remains the choice among the orally administered
antibiotics, followed by gentamicin, second and third generation cephalosporins. To
treat severe illness one may use the injectable antibiotics, and among then, we should
choice aminoglycosides, third generation cephalosporin, fluoroquinolones or
imipenem, which were the most effective ones. The high resistance patterns to
ampicillin, amikacin and cephradin, should be remembered.
CONCLUSION
The most common community acquired UTI is caused by negative-Gram agents.
nitrofurantion remains the choice among the orally administered antibiotics, followed
by gentamicin second and third generation cephalosporins. For severe disease that
require parenteral antibiotics the choice should be aminoglycosides, third generation
cephalosporin, fluoroquinolones or imipenem, which were the most effective.
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