Tehran University Medical Journal

Background: Campylobacter genus is considered some of the most important agents of bacterial gastroenteritis worldwide. Campylobacter coli (C. coli) is accounted to at least 25% of all Campylobacter related diarrheal diseases moreover, C. coli infections can result in severe complications, such as bacteremia, sepsis, meningitis and spontaneous abortion. Finally, there is evidence that the frequency of antimicrobial resistance is higher in C. coli, when compared to C. jejuni. There is no data regarding the frequency and antibiotic resistance profile of C. jejuni isolated from human gastroenteritis samples. The present study aimed to determine the frequency and antibiotic resistance patterns of Campylobacter coli isolated from infectious diarrhea samples.
Methods: In a descriptive cross-sectional study, 200 infectious diarrhea samples collected in Arak University of Medical Sciences Hospitals, Markazi Province, Iran, from May to November 2015 were subjected to the study. In order to identify C. coli modified Gram stain, modified charcoal-cefoperazone-deoxycholate agar (mCCDA) and Brucella agar media with filter and CeuE gene polymerase chain reaction (PCR) were accomplished. Antibiotic resistance against tetracycline, erythromycin, ciprofloxacin, ampicillin and gentamicin was evaluated phenotypically and genotypically.
Results: In total, out of 200 modified gram stained samples, 2 cases (1%) of C. coli were identified. Cultivating methods using mCCDA medium found 2 isolates (1%), 3 isolates (1.5%) were grown on Brucella agar with filter and 5 cases (2.5%) were determined as C. coli using PCR assay. Antibiotic resistance was observed in 5 cases against tetracycline, erythromycin and ciprofloxacin (100%), in 4 cases against ampicillin (80%), in 2 cases against gentamicin (40%), in 5 cases with CmeB, 23srRNA mutation in, qnrS, tet (o) (100%), in 4 cases with gyrA4 (80%), in 3 cases with gyrA5 (60%), in 5 cases with gyrA6 (100%), in 4 cases with Oxa61 (60%) and in 1 case with aphA-3-1 (20%).
Conclusion: In this present study C. coli with low prevalence and entire resistance to ciprofloxacin and erythromycin which are the first line antibiotic for the treatment of campylobacter gastroenteritis is introduced as a causative agent of gastroenteritis in patients at central part of Iran.

Background: It is difficult to treat infections caused by Acinetobacter baumannii due to multiple drug resistance. The aim of this study was to determine the efficacy of combination therapy with two broad-spectrum antibiotics colistin and rifampin on clinical and para clinical indexes of the patients with ventilator-dependent pneumonia due to imipenem-resistant to A. baumannii in intensive care units of a tertiary hospital.

Methods: In a descriptive cross-sectional study, fifty patients admitted to the intensive care units in Vali-Asr Hospital, Arak, Iran, from October 2014 to May 2015, with established ventilator-associated pneumonia were subjected to this study and were treated with standard dosage of colistin and rifampin daily. Once the minimum inhibitory concentration (MIC) of the A. baumannii isolates were susceptible to colistin (MIC˂2 µg/ml) and rifampin (MIC˂2 µg/ml) they were treated with three million international units of colistin in 100 ml of normal saline three times a day and 600 mg of rifampin daily. Side effects of combination therapy and variables of patients like fever, blood pressure, white blood cell count, differential count and, mortality were documented and statistically analyzed.
Results: 31(62%) patients were improved after combined treatment with colistin and rifampin, 4(8%) patients were died due to bloodstream infection with A. baumannii and 15(30%) passed away in effect of other reasons. The mean of BUN (P=0.07) and creatinine significantly increased (P=0.02). Clinical variables such as fever, white blood cell count, white blood cell percentage and red blood cell sedimentation rate significantly decreased (P≤0.05).
Conclusion: Colistin and rifampicin appear to be an effective and safe combination therapy for treatment of ventilator-dependent pneumonia due to imipenem-resistant to A. baumannii