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Hypervirulent Klebsiella pneumoniae as a hospital-acquired pathogen in the intensive care unit in Mansoura, Egypt.

Introduction

Klebsiella pneumoniae can cause both community- and hospital-acquired (HA) infections. (1) There are two different groups of Klebsiella pneumoniae: classical (cKP) and hypervirulent (hvKP). (2) cKP used to describe the commonly known strains of K. pneumoniae, which are responsible for most HA infections, in immunocompromised patients. (3) The hvKP was first identified in Taiwan in 1986;4 these new variants have the ability of causing metastatic and life-threatening infections in healthy persons in the community. (5) Recently, hvKP infection is increasingly reported in other countries. (6,7)

Several virulence factors have been detected in K. pneumoniae, such as the capsule that protects bacteria from both phagocytosis and lethal serum factors, plasmid-borne rmpA (regulator of mucoid phenotype A), fimbriae, lipopolysaccharides and siderophores. (3,6,8) The kind and number of virulence factors influence the type of K. pneumoniae infections. (9) Moreover, the infectivity is exacerbated by the capacity of K. pneumoniae to acquire multiple drug resistance. (1)

Many studies have reported the role of hvKP in community-acquired infection, (4,5) but there are limited studies on its role in HA infections.

This study was conducted to evaluate the frequency of hvKP among HA K. pneumoniae infections in the intensive care unit (ICU) and to compare virulence and antibiotic susceptibility between hvKP and cKP.

Methods

A cross-sectional study was conducted for a period of six months from June to December 2015 in 3 ICUs (2 medical ICUs and 1 surgical ICU) in Mansoura University Hospital, Mansoura, Egypt. The study was approved by the Institutional Research Board at the Faculty of Medicine, Mansoura University (No. R/16.12.75). Infections were considered as HA when a new infection developed 48 hours after patient admission. Samples were collected from patients with HA infections. Non-repetitive consecutive isolates were identified as K. pneumoniae by Gram stain, colony morphology, Kligler iron agar, oxidase test, Lysine iron agar, methyl red, Voges-Proskauer test, citrate tests, motility indole ornithine, (10) and confirmed by API 20E (BioMerieux, Marcy l'Etoile, France).

Antibiotic susceptibility testing

Antibiotic susceptibility testing was done for all isolates of K. pneumoniae by the disk diffusion method according to CLSI guidelines. (11) The following antimicrobial agents were tested: ampicillin, amoxicillin-clavulanate, cefoperazone-sulbactam, cefoxitin, aztreonam, cefepime, ceftazidime, cefotaxime, ciprofloxacin, gentamicin, imipenem, meropenem (Oxoid, Altrincham, Cheshire, UK).

Extended-spectrum beta lactamase production (ESBL) and plasmid-mediated AmpC [beta]-lactamases (pAmpC) were tested by double disk synergy test and modified three dimensional test respectively. (12,13)

String test

Bacterial colonies on an agar plate were extended by a standard bacteriological loop. If a mucoviscous string >5 mm in length was formed, it was considered positive string and the stain was identified as hypermucoviscous. (14)

Serum resistance assay

The serum resistance assay was done as previously described. (15) Then, survival of bacteria in normal human serum was documented over a period of three hours and classified into six grades. The strains were considered as highly sensitive (grades 1 and 2), intermediately sensitive (grades 3 and 4), or resistant (grades 5 and 6). (16)

Biofilm formation

Biofilm formation was evaluated by the semiquantitative assay in 96-well flat bottom plates, as previously described. (17)

Capsular polysaccharide genotyping, virulence factors and [beta]-lactamase genes detection

Genomic DNA was extracted by Gene JET genomic DNA purification kit (Thermo Fisher Scientific, Waltham, MA, USA). Detection of capsular serotype-specific genes K1, K2, K5, K20, K54, K57, virulence genes: rmpA, rmpA2, iucA, and iroB and [beta]-lactamase genes: SHV and TEM was performed by polymerase chain reaction. The presence of iucA, or iroB genes was used to identify probable hvKP. Primers used in this study are listed in Table 1.

PCR conditions used for capsular genotyping were applied as previously described. (5) Multiplex PCR was done for rmpA, rmpA2 in the same conditions as previously described. (6) PCR conditions for iucA included an initial denaturation at 95[degrees]C for 15 min, followed by denaturation at 95[degrees]C for 15 s, annealing at 49[degrees]C for 15 s, and extension at 72[degrees]C for 1 min for 30 cycles, followed by a final extension for 10 min at 72[degrees]C. PCR conditions for iroB were the same as those used in iucA but the annealing temperature was 55[degrees]C. PCR conditions for SHV and TEM [beta]-lactamase were applied as previously described. (18)

Statistical analysis

Data were statistically analyzed using the Statistical Package for Social Sciences (SPSS) version 16 (SPSS Inc, Chicago, IL, USA). Qualitative data are described as numbers and percentages. The Chi-square test or Fisher's exact test were used for comparison between groups, as appropriate. Results with p<0.05 were considered significant.

Results

Patient characteristics

A total number of 65 isolates of K. pneumoniae were isolated from 65 patients with hospital-acquired infections in the ICUs of Mansoura University Hospital. The strains were isolated as follows: 11 from blood, 21 from urine, 26 from respiratory secretions and 7 from wound.

Four strains were identified as probable hvKP based on being positive for either iucA, or iroB gene. All hvKP strains were MDR. All hvKP were isolated from Egyptian patients, none of these patients had travelled abroad in the last year. No metastatic infection was reported in hvKP-infected patients. Characteristics of these hypervirulent strains are shown in Table 2.

A significantly higher number of hvKP was recovered from diabetic patients (p=0.004). Otherwise, no significant differences in the underlying conditions of patients were recorded between hvKP and cKP strains. Differences between the clinical characteristics of patients with hvKP and cKP are shown in Table 3.

Comparison between hvKP and cKP isolates

In the hypervirulent strains, the capsule K1 and K2 genes were present in two and one of the isolates respectively; no K5, K20, K54 and K57 serotype genes were found. Two isolates were positive for both rmpA and rmpA2 genes (50%), one isolate (25%) was positive for rmpA2 only. Hypermucoviscosity was detected in all hvKP isolates and 8.2% of cKP. At the same time, all cKP isolates were non-typable and they did not carry any of the tested virulence genes. There was no significant difference between hvKP and cKP strains in terms of serum resistance or biofilm formation Table 4.

Antimicrobial susceptibility testing

There was no significant difference between hvKP and cKP strains in the resistance pattern. The results of antimicrobial susceptibility testing for hvKP and cKP are summarized in Table 5.

Discussion

Hypervirulent Klebsiella pneumoniae are rising variants that cause serious community-acquired infection. (3) In the current study, probable hvKP identified by the presence of the iucA or iroB gene represented 6.2% of HA K. pneumoniae infections in ICUs. On the other hand, a higher prevalence of the hvKP in different HA infections has been previously reported. (2,19)

The hypermucoviscosity phenotype was detected in 13.8% of all K. pneumoniae isolates. These phenotypes were more significantly detected in hvKP. In previous studies, the prevalence of hvKP varied from 7.8% to 25.4, (20,21) whereas another study conducted in Egypt reported that about 40% of K. pneumoniae isolates were hypermucoviscous. (22)

The capsule is a major virulence factor in K. pneumoniae, with 78 capsular polysaccharides identified. K1, K2, K5, K16, K20, K54, K57 and KN1, are documented in hvKP. (3,5) In this study, while all cKP isolates were non-typable, serotypes K1, K2 have been recognized in 2 and 1 isolate respectively of hvKP.

The rmpA and rmpA2 are genes that regulate the synthesis of extracellular polysaccharide capsule. (3) In this study, these genes were significantly associated with hvKP isolates, as previously reported. (23,24) Moreover, they were only present in hvKP strains with serotypes K1, K2 and not present in any non-typable strains. These findings are in line with other published results, which state that they are extremely uncommon in serotypes other than K1, K2, K5, K16, K20, K54, K57.25 On the other hand, Zhang et al. (26) found a lack of direct correlation between hypermucoviscosity and the expression of rmpA in hvKP strains.

There was no significant difference in biofilm production and serum resistance between hvKP when compared to cKP. Yan et al. (23) reported that there was a significant association between these genes and hvKP but not with cKP. On the contrary, Fang et al. (14) detected high serum resistance in hvKP. Virulence genes were detected at a lower rate compared to other studies. (27) This difference may be due to geographic differences or because other studies were conducted in community-acquired infections. (9)

The coexistence of virulence factors such as the rmpA gene, siderophores and biofilm production with hvKP strains carrying genes for K1 and K2 indicate a high virulence of these strains. It has also been previously stated that strains serotype K1 or K2 are particularly virulent. (28) In addition, these isolates carry also rmpA genes. The presence of rmpA may suggest the presence of a plasmid containing other virulence-associated genes. (8) Recently, Zhang et al. (19) defined hvKP by positive aerobactin isolates. For these reasons, using the string test for defining hvKP may not be adequately sensitive. Different virulence factors other than hypermucoviscosity participate more significantly in the virulence of K. pneumoniae isolates. (29)

In agreement with a previous study, diabetes mellitus is considered a predisposing factor for acquiring hvKP infections, (19) while there was no significant difference between hvKP and cKP infections with other underlying diseases. (7,23,30)

Although hvKP isolates were considered less resistant than cKP, multidrug resistance and even carbapenem resistance emerged in hvKP isolates. (24) In this study, although all hvKP isolates were sensitive to carbapenem, they were MDR. Moreover, one isolate was an ESBL producer and this isolate carried the SHV gene; another two isolates were pAmpC producers. The rate of resistance among our hvKP isolates was higher than that from previous studies. (5,19,23)

Conclusion

hvKP detected in the ICU may form a new threat for critically ill patients especially if they are associated with antibiotic resistance. Although the validity of the string test in detecting metastatic Klebsiella is questionable, it is a simple and easy test that can be done in any laboratory indicating the presence of this organism. Serotypes or aerobactin genomic background may provide helpful and confirmatory tools to diagnose hvKP.

doi: 10.18683/germs.2018.1141.

Received: 06 July 2018; revised: 29 August 2018; accepted: 30 August 2018.

Authors' contributions statement: RE, GE, HS designed the study. RE did microbiology, molecular biology laboratory work, the analysis and interpretation of data. All authors prepared the first draft, read and approved the final manuscript.

Conflicts of interest: All authors--none to disclose.

Funding: None to declare.

References

(1.) El Fertas-Aissani R, Messai Y, Alouache S, Bakour R. Virulence profiles and antibiotic susceptibility patterns of Klebsiella pneumoniae strains isolated from different clinical specimens. Pathol Biol (Paris) 2013;61:209-16. [Crossref]

(2.) Liu C, Guo J. Characteristics of ventilator-associated pneumonia due to hypervirulent Klebsiella pneumoniae genotype in genetic background for the elderly in two tertiary hospitals in China. Antimicrob Resist Infect Control 2018;7:95. [Crossref]

(3.) Shon AS, Bajwa RP, Russo TA. Hypervirulent (hypermucoviscous) Klebsiella pneumoniae: a new and dangerous breed. Virulence 2013;4:107-18. [Crossref]

(4.) Liu YC, Cheng DL, Lin CL. Klebsiella pneumoniae liver abscess associated with septic endophthalmitis. Arch Intern Med 1986;146:1913-6. [Crossref]

(5.) Fang CT, Lai SY, Yi WC, Hsueh PR, Liu KL, Chang SC. Klebsiella pneumoniae genotype K1: an emerging pathogen that causes septic ocular or central nervous system complications from pyogenic liver abscess. Clin Infect Dis 2007;45:284-93. [Crossref]

(6.) Nadasy KA, Domiati-Saad R, Tribble MA. Invasive Klebsiella pneumoniae syndrome in North America. Clin Infect Dis 2007;45:e25-8. [Crossref]

(7.) Liu YM, Li BB, Zhang YY, et al. Clinical and molecular characteristics of emerging hypervirulent Klebsiella pneumoniae bloodstream infections in mainland China. Antimicrob Agents Chemother 2014;58:5379-85. [Crossref]

(8.) Chen YT, Chang HY, Lai YC, Pan CC, Tsai SF, Peng HL. Sequencing and analysis of the large virulence plasmid pLVPK of Klebsiella pneumoniae CG43. Gene 2004;337:189-98. [Crossref]

(9.) Yu VL, Hansen DS, Ko WC, et al. Virulence characteristics of Klebsiella and clinical manifestations of K. pneumoniae bloodstream infections. Emerg Infect Dis 2007;13:986-93. [Crossref]

(10.) Mahon CR, Lehman DC, Manuselis Jr G. Textbook of diagnostic microbiology. Maryland Heights, Missouri, USA: Saunders Elsevier; 2014.

(11.) Wayne P. Clinical and Laboratory Standards Institute (CLSI) performance standards for antimicrobial disk diffusion susceptibility tests. 19th ed. approved standard. CLSI document M100-S19 2009;29.

(12.) Jarlier V, Nicolas MH, Fournier G, Philippon A. Extended broad-spectrum beta-lactamases conferring transferable resistance to newer beta-lactam agents in Enterobacteriaceae: hospital prevalence an susceptibility patterns. Rev Infect Dis 1988;10:867-78. [Crossref]

(13.) Coudron PE, Moland ES, Thomson KS. Occurrence and detection of AmpC beta-lactamases among Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis isolates at a veterans medical center. J Clin Microbiol 2000;38:1791-6.

(14.) Fang CT, Chuang YP, Shun CT, Chang SC, Wang JT. A novel virulence gene in Klebsiella pneumoniae strains causing primary liver abscess and septic metastatic complications. J Exp Med 2004;199:697-705. [Crossref]

(15.) Podschun R, Sievers D, Fischer A, Ullmann U. Serotypes, hemagglutinins, siderophore synthesis, and serum resistance of Klebsiella isolates causing human urinary tract infections. J Infect Dis 1993;168:1415-21. [Crossref]

(16.) Sahly H, Aucken H, Benedi VJ, et al. Increased serum resistance in Klebsiella pneumoniae strains producing extended-spectrum beta-lactamases. Antimicrob Agents Chemother 2004;48:3477-82. [Crossref]

(17.) Sanchez CJ Jr, Mende K, Beckius ML, et al. Biofilm formation by clinical isolates and the implications in chronic infectio ns. BMC Infect Dis 2013; 13:47. [Crossref]

(18.) Zaniani FR, Meshkat Z, Nasab MN, et al. The prevalence of TEM and SHV genes among extended-spectrum betalactamases producing Escherichia coli and Klebsiella pneumoniae. Iran J Basic Med Sci 2012;15:654-60.

(19.) Zhang Y, Zhao C, Wang Q, et al. High prevalence of hypervirulent Klebsiella pneumoniae infection in China: geographic distribution, clinical characteristics, and antimicrobial resistance. Antimicrob Agents Chemother 2016;60:6115-20. [Crossref]

(20.) Togawa A, Toh H, Onozawa K, et al. Influence of the bacterial phenotypes on the clinical manifestations in Klebsiella pneumoniae bacteremia patients: a retrospective cohort study. J Infect Chemother 2015;21:531-7. [Crossref]

(21.) Ikeda M, Mizoguchi M, Oshida Y, et al. Clinical and microbiological characteristics and occurrence of Klebsiella pneumoniae infection in Japan. Int J Gen Med 2018;11:293-9. [Crossref]

(22.) Abd-Elmonsef MM, Khalil HS, Selim A, et al. Detection of hypervirulent Klebsiella pneumoniae in Tanta University Hospital, Egypt. Br Microbiol Res J 2016;17:1-10.

(23.) Yan Q, Zhou M, Zou M, Liu WE. Hypervirulent Klebsiella pneumoniae induced ventilator-associated pneumonia in mechanically ventilated patients in China. Eur J Clin Microbiol Infect Dis 2016;35:387-96. [Crossref]

(24.) Li W, Sun G, Yu Y, et al. Increasing occurrence of antimicrobial-resistant hypervirulent (hypermucoviscous) Klebsiella pneumoniae isolates in China. Clin Infect Dis 2014;58:225-32. [Crossref]

(25.) Hsu CR, Lin TL, Chen YC, Chou HC, Wang JT. The role of Klebsiella pneumoniae rmpA in capsular polysaccharide synthesis and virulence revisited. Microbiology 2011;157:3446-57. [Crossref]

(26.) Zhang Y, Zeng J, Liu W, et al. Emergence of a hypervirulent carbapenem-resistant Klebsiella pneumoniae isolate from clinical infections in China. J infect 2015;71:553-60. [Crossref]

(27.) Lee CH, Liu JW, Su LH, Chien CC, Li CC, Yang KD. Hypermucoviscosity associated with Klebsiella pneumoniaemediated invasive syndrome: a prospective crosssectional study in Taiwan. Int J Infect Dis 2010;14:e68892. [Crossref]

(28.) Siu LK, Yeh KM, Lin JC, Fung CP, Chang FY. Klebsiella pneumoniae liver abscess: a new invasive syndrome. Lancet Infect Dis 2012;12:881-7. [Crossref]

(29.) Lin YC, Lu MC, Tang HL, et al. Assessment of hypermucoviscosity as a virulence factor for experimental Klebsiella pneumoniae infections: comparative virulence analysis with hypermucoviscosity-negative strain. BMC Microbiol 2011;11:50. [Crossref]

(30.) Yao B, Xiao X, Wang F, Zhou L, Zhang X, Zhang J. Clinical and molecular characteristics of multi-clone carbapenem-resistant hypervirulent (hypermucoviscous) Klebsiella pneumoniae isolates in a tertiary hospital in Beijing, China. Int J Infect Dis 2015;37:107-12. [Crossref]

(31.) Russo TA, Olson R, MacDonald U, Beanan J, Davidson BA. Aerobactin, but not yersiniabactin, salmochelin, or enterobactin, enables the growth/survival of hypervirulent (hypermucoviscous) Klebsiella pneumoniae ex vivo and in vivo. Infect Immun 2015;83:3325-33. [Crossref]

Rasha EL-Mahdy [1], *, Ghada El-Kannishy [2], Hassan Salama [3]

[1] MD, Department of Medical Microbiology and Immunology, Faculty of Medicine, Mansoura University, Mansoura, 35516, Egypt; [2] MD, Department of Internal Medicine, Faculty of Medicine, Mansoura University, Mansoura, 35516, Egypt; [3] MD, Department of Neurology, Faculty of Medicine Mansoura University, Mansoura, 35516, Egypt.

* Corresponding author: Rasha El-Mahdy, MD, Department of Medical Microbiology and Immunology, Faculty of Medicine, Mansoura University, Mansoura, 35516, Egypt. rashaamr@mans.edu.eg
Table 1. Specific primers used for capsule
genotyping and for various virulence genes of K.
pneumoniae

Gene           Primers sequence          References

K1        5'-GTAGGTATTGCAAGCCATGC-3'         5
          5'-GCCCAGGTTAATGAATCCGT-3'
K2        5'-GGAGCCATTTGAATTCGGTG-3'         5
          5'-TCCCTAGCACTGGCTTAAGT-3'
K5        5'-GCCACCTCTAAGCATATAGC-3'         5
          5'-CGCACCAGTAATTCCAACAG-3'
K20       5'-CCGATTCGGTCAACTAGCTT-3'         5
          5'-GCACCTCTATGAACTTTCAG-3'
K54       5'-CATTAGCTCAGTGGTTGGCT-3'         5
          5'-GCTTGACAAACACCATAGCAG-3'
K57       5'-CGACAAATCTCTCCTGACGA-3'         5
          5'-CGCGACAAACATAACACTCG-3'
rmpA      5'-ACTGGGCTACCTCTGCTTCA-3'         6
          5'-CTTGCATGAGCCATCTTTCA-3'
rmpA2     5'-CTTTATGTGCAATAAG-GATGTT-3'     27
          5'-CCTCCTGGAGAGTAAGCATT-3'
iucA      5'-ATAAGGCAGGCAATCCAG-3'          31
           5'-TAACGGCGATAAACCTCG-3'
iroB      5'-TGTGTGCTGTGGGTGAAAGC-3'         31
         5'-ATGTTCGGTGAGATTCGCCAGT-3'
SHV        5'-TCAGCGAAAAACACCTTG -3          18
            5'-CCCGCAGATAAATCACCA
TEM      5'-GAGTATTCAACATTTCCGTGTC-3         18
         5'-TAATCAGTGAGGCACCTATCTC-3'

Table 2. Microbiological and genetic characteristics of
hypervirulent Klebsiella pneumoniae strains

No   Sample                  Biofilm   Serum resistance   Capsule

1    Endotracheal aspirate      +          Grade 6          K1
2    Wound                      +          Grade 5          K1
3    Endotracheal aspirate      -          Grade 6           -
4    Wound                      +          Grade 5          K2

No   rmpA rmpA2    String test   iucA   iroB   SHV   TEM

1    rmpA, rmpA2        +         +      -      +     -
2    rmpA rmpA2         +         +      +      -     -
3         -             +         +      -      -     -
4       rmpA2           +         +      -      -     -

Grade 5--the viable count after 1, 2, and 3 hours was >100%;
however, the viable count fell sometime in the 3-hour period.
Grade 6--the viable count after 1, 2, and 3 hours was >100%
of the inoculum and increased during the 3-hour period.

Table 3. Clinical characteristics of patients with hypervirulent
Klebsiella pneumoniae (hvKP) and classical Klebsiella pneumoniae
(cKP)

Variable                    hvKP       cKP       P-value
                            (n=4)     (n=61)

Age >60 years                 2         30          1
Male                          1         40        0.138
Prolonged hospitalization     1         45        0.072
Coexisting condition
Diabetes mellitus             4         13       0.004*
Liver cirrhosis               2         12        0.200
Chronic renal failure         1         2         0.176
Neurological disease          3         16        0.072
Pulmonary disease             2         11        0.176
Malignancy                    1         2         0.176
Invasive devices
Endotracheal intubation       3         29        0.355
Urinary catheter              3         30        0.613
Central venous catheter       2         13        0.226
Infection
Bloodstream infections        0         11          1
Urinary tract infections      0         21        0.296
Pneumonia                     2         24          1
Surgical site infections      2         5         0.054
Mortality                     2         6         0.070

Variable                    Odds ratio   95% confidence
                                            interval

Age >60 years                 1.033       0.137-7.815
Male                          5.714       0.559-58.379
Prolonged hospitalization     8.438       0.818-87.065
Coexisting condition
Diabetes mellitus             1.308       1.005-1.702
Liver cirrhosis               4.083       0.521-32.010
Chronic renal failure         9.833      0.684-141.432
Neurological disease          8.438       0.818-87.065
Pulmonary disease             4.545       0.576-35.871
Malignancy                    9.833      0.684-141.432
Invasive devices
Endotracheal intubation       3.310       0.326-33.627
Urinary catheter              3.100       0.305-31.487
Central venous catheter       3.692       0.474-28.783
Infection
Bloodstream infections        0.926       0.859-0.998
Urinary tract infections      0.909       0 .828-0.998
Pneumonia                     1.542       0.203-11.693
Surgical site infections       11.2       1.288-97.404
Mortality                     9.167       1.086-77.402

Prolonged hospitalization was defined as >2 weeks. Data
are no. of patients.

*A p-value of <0.05 was considered to be statistically
significant.

Table 4. Comparison of serotypes and virulence genes of
hypervirulent Klebsiella pneumoniae (hvKP) and classical
Klebsiella pneumoniae (cKP)

Variable             hvKP     cKP     P-value
                     (n=4)   (n=61)

Serotypes

K1                     2       0       0.003 **
K2                     1       0       0.062
K5                     0       0        N/A
K20                    0       0        N/A
K54                    0       0        N/A
K57                    0       0        N/A
Non-typable            1       61     <0.001 *

Virulence

rmpA or rmpA2          3       0      <0.001 *
Hypermucoviscosity     4       5      <0.001 *
Biofilm formation      3       27      0.328
Serum resistance       3       41        1

Variable             Odds    95% confidence
                     ratio      interval

Serotypes

K1                   0.032    0.008-0.124
K2                   0.047    0.016-0.141
K5                    N/A         N/A
K20                   N/A         N/A
K54                   N/A         N/A
K57                   N/A         N/A
Non-typable           62     8.873-433.212

Virulence

rmpA or rmpA2        0.016    0.002-0.113
Hypermucoviscosity    1.8     1.003-3.229
Biofilm formation    3.778    0.372-38.398
Serum resistance     1.463    0.143-14.973

N/A--not applicable.

Data are no. of patients.

* A p-value of <0.05 was considered to be
statistically significant.

Table 5. Antimicrobial resistance pattern of
hypervirulent Klebsiella pneumoniae (hvKP) and
classical Klebsiella pneumoniae (cKP)

Variable                  hvKP     cKP     P-value
                          (n=4)   (n=61)

Ampicillin                  4       61       N/A
Amoxicillin-clavulanate     3       55      0.373
Cefoperazone-sulbactam      3       51      0.533
Cefoxitin                   4       58        1
Cefotaxime                  4       56        1
Ceftazidime                 3       58      0.229
Cefepime                    4       57        1
Ciprofloxacin               2       46      0.278
Gentamicin                  3       55      0.373
Aztreonam                   4       57        1
Imipenem                    0       8         1
Meropenem                   0       10        1
ESBL                        1       29      0.618
pAmpC                       2       34        1

Variable                  Odds    95% confidence
                          ratio      interval

Ampicillin                 N/A         N/A
Amoxicillin-clavulanate   3.056    0.273-34.190
Cefoperazone-sulbactam    1.700    0.160-18.050
Cefoxitin                 0.935    0.876-0.999
Cefotaxime                0.933    0.872-0.999
Ceftazidime               6.444    0.507-81.988
Cefepime                  0.934    0.874-0.999
Ciprofloxacin             3.067    0.397-23.697
Gentamicin                3.056    0.273-34.190
Aztreonam                 0.934    0.874-0.999
Imipenem                  1.075    1.001-1.155
Meropenem                 1.078    1.001-1.161
ESBL                      0.368    0.036-1.068
pAmpC                     0.794    0.105-6.011

Data are no. of patients.

ESBL--extended spectrum ([beta]-lactamase; N/A--not applicable.
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Title Annotation:Original article
Author:Mahdy, Rasha EL-; Kannishy, Ghada El-; Salama, Hassan
Publication:GERMS
Article Type:Report
Geographic Code:7EGYP
Date:Sep 1, 2018
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