Characterization and resistance pattern of bacterial isolates from pus samples in a tertiary care hospital, Karimnagar

Background: Wound infection can cause delayed healing, chronicity which indirectly causes financial burden and psychological stress on patients. Aim: To speciate the organism isolated from pus sample received and its antibiotic sensitivity test. Methods and materials: All isolated organism are identified by colony morphology, Gram stain and biochemical reactions. Antibiotic sensitivity test for all isolates were done by Kirby-Bauer method using Mueller Hinton agar. Results: The major contribution of sample was from surgery department (65.3%) followed by orthopedics (10.2%). A total of 383 organism isolated among which Klebsiella pneumoniae dominates (34.46%) followed by Staphylococcus aureus (18.53%). All Gram negative organisms showed maximum resistance to amoxyclav and least to Imipenem. All Gram positive organisms showed least resistance to Vancomycin and Linezolid. Pseudomonas aeruginosa showed maximum resistance to amoxyclav (66.1%) and Gentamicin (57.1%) and least to Imipenem (7.1%). Conclusion: It is observed from the present study that, there is an increase in the resistance among beta-lactam antibiotics and quinolones. Emergence of drug resistance can be effectively controlled by continuous surveillance in hospitals and rational use of antibiotics.


Introduction
Wound infections are associated with higher rate of morbidity, mortality and increased medical expenses. Surgical wound infections are second most common cause of wound infections [1,2]. Treating wound infection mainly depends upon understanding of causative pathogen, pathophysiology of infective process and pharmacokinetics of drugs used for treatment [3]. There is increase in the development of resistance especially in developing countries due to indiscriminate use of antibiotics [4]. Bacteria have the ability to acquire resistance to therapeutic drugs and can transfer the resistance from one bacteria to another [5].
This study is conducted to know the prevalence of bacterial isolates from pus samples and its antibiotic sensitivity pattern which guides for appropriate therapy and framing antibiotic policies for hospital.

Results
Of total population 64 % were male.  Frequency of bacterial isolation was maximum among

Research Article
Tropical Journal of Pathology & Microbiology Available online at: www.pathologyreview.in 53 | P a g e

Discussion
In this study there is male predominance and majority of patients are in age group 20-40 followed by 40-60 which is seen in previous study [1].
In present study Staphylococcus aureus is the predominant organism among Gram positive organisms which is comparable with many studies [4,8,9]. Among CONS, Staphylococcus epidermidis predominates followed by Staphylococcus saprophyticus which is in according with study conducted by Mohan U at al [10].
Klebsiella pneumonia is predominant organism isolated in our study with similar findings shown in studies by Sharma V et al [11] and Panta K et al [12], but in the study conducted by Kumar AR et al [4] and Verma P et al [13] it was second most common isolate.
Resistance pattern of S. aureus as seen in table 7 shows maximum resistance to amoxyclav (53.5%) followed by Ofloxacin (46.5%). Resistance for third generation cephalosporin like Cefotaxime and Ceftriaxone differ by narrow percentage with 40.5 and 39.4 respectively which is similar to study done at Jodhpur by Duggal S at al [14].

Escherichia coli and
Here in our present study Pseudomonas aeruginosa showed prevalence of about 14.6%.
Pseudomonas aeruginosa encountered maximum resistance to amoxyclav (66.1%) and least to Imipenem (7.1%). Gentamicin resistance was 57.1% which is in accordance with work done by Hosimin K et al [19] which showed 50% resistance. Least resistance to Imipenem was reported by Duggal S at al [14] which is similar to our present study but same study showed Ofloxacin resistance of 72% where as in our study it is only 39.3%.

Conclusion
The present study showed alarming increase in the resistance to amoxyclav and third generation cephalosporins for all the isolates which is a serious problem in local area. To combat this we strongly advocate for rational use of antibiotics.