الفهرس 
Literature ReviewOnly 14 pages are availabe for public view
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Abstract
Pseudomonas aeruginosa (P. aeruginosa) and
Acinetobacter baumannii (A. baumannii) are both
characterized by innate resistance mechanisms against
multiple antimicrobials. Furthermore, these pathogens may
easily acquire new resistances by different mobile
elements, thus making extremely challenging the choice of
appropriate antibiotic therapy. In this study, 70 clinical
isolates provided from ICU El-Demardash hospital. All
bacterial isolates identified by the standard microbiological
methods including cultural morphology, microscopic
examination and biochemical tests and vitek II cards. these
indicated that 25 P. aeruginosa and 25 as A. baumanniii.
According to patients’ gender Among P. aeruginosa, 18
(72%) were males and 7 (28%) were females while in A.
baumannii17 (72%) were females and 8 (28%) were males
According to age, the isolates were divided into3 groups: 1
- 14 year, 14 - 30and > 45 years. The high percentage of
isolates was found in > 45 and1-14 years were 48 and 52%
in P. aeruginosa and A. baumanni, respectively. the highest
number of P. aeruginosa isolates were recovered from
wound (52%) followed by blood (16%). Lower percentages
were detected in urine, sputum, CSF and plural fluid
samples, 12, 12, 4 and 4%, respectively. blood isolates had
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the highest percentage in A. baumanni were 52% followed
by 32 %, 12% and 4% were sputum, CSF and wound,
respectively.
Antibiotic sensitivity and minimum inhibitory
concentration (MIC) for 18 different antibiotics
(Ticarcillin, Ticarcillin /Clavulanic acid, Piperacillin,
Piperacillin-Tazobactam, Ceftazidime, Cefepime,
Meropenem, Amikacin, Gentamicin, Aztreonam,
Imipenem, Meropenem, Tobramycin, Ciprofloxacin,
Plefloxacin, Minocyclin, Rifampcin,
Trimethothoprim/Sulfamethoxazole and colistin) were
carried out against all both isolates using VITEK 2 and disck
diffusion method. All isolates were resistant to all these
tested antibiotics except they were sensitive to Colistin.
By using PCR, different OXA genes were detected.
In P. aeruginosa OXA group I and group II were detected
in 44 and 52%, respectively. These 2 groups were coexisted
in 8 isolates. While group III, OXA51, OXA23, OXA24 and
OXA58 were totally absent. While for A. baumanni, all
isolates were found to have OXA51 (100%), however for
OXA23, OXA24 and OXA58 were detected in 88, 60 and
60%, respectively. where (OXA51, OXA23 and OXA24),
(OXA51, OXA23and OXA58), (OXA51 and OXA23) and
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(OXA51and OXA58), were coexisted in 5, 3, 4 and 1
isolates, respectively.
Both P. aeruginosa and A. baumannii clinical
isolates were able to form biofilm with different extents.
Only 44% of P. aeruginosa showed strong biofilm
formation, while moderate and weak biofilm formation
were detected in 28 and 12% of the isolates, respectively.
No biofilm formation was detected in16% of P. aeruginosa
isolates. In A. baumannii 76 and 24% were weak and
moderate forming biofilm, respectively.
All isolates were sensitive to colistin at ≥ 0.5mg
according to Vitek 2, the MIC results using the Microtiter
plate confirmed that a total 7 isolates (3 P. aeruginosa and
4 A. baumannii) were resistant to colistin at ≤ 4 mg,
respectively General Conclusions and Recommendations
• all isolates isolated from ICUs where Elderly patients
were the most common group in in P. aeruginosa
moreover young age were the higher percentage group in
A. baumannii, they are also more susceptible to be
infected with nosocomial infections. Therefore, all
possible precautions must be achieved to protect them
from these infections.
• the highest numbers of P. aeruginosa were isolated
from wound and blood isolates had the highest
percentage in A. baumannii
• 86% of both isolates were XDR (resistantto all
antibiotic classes except colistin) and 14% were PDR
(resistant to all antibiotics classes in addition to colistin
where 88 and 84% were XDR P. aeruginosa and XDR
A. baumannii
• Formation of biofilm give a good reason in addition to
presence of OXA genes for these resistant isolates in both
P. aeruginosa and A. baumannii
• Colistin sensitivity must be determined not only by Vitek2
but also by MIC method.
• A restriction in the prescription of Carbapenems is
necessary. In addition, new strategies for treatment are an
urgent needed as alternative therapeutic options.
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• Continuous monitoring systems and effective infection
control criteria have to be obligatory established in
hospitals