Shahraki, Sh, Bokaeian, M, Rigi, Sh,
Volume 8, Issue 4 (supplement Issue[PERSIAN] 2015)
Abstract
Abstract Background and Objective: Klebsiella pneumoniae is an opportunistic nosocomial pathogen causing a variety of infections including urinary tract infections, pneumonia, septicemia, wound infections and infections in the intensive care units. Since the ESBL producing Klebsiella pneumoniae strains are increasingly causing urinary tract infections, we aim to assess antibiotic resistance pattern and evaluate the prevalence of ESBL in Klebsiella pneumoniae isolated from urinary tract infections. Material and Methods: this cross-sectional study was conducted on 122 Klebsiella pneumoniae strains collected from Zahedan hospitals. After final identification of isolates, antibiotic susceptibility tests were carried out by using disk diffusion in agar method for 16 antibiotics and ESBL production was determined by the combined disk method. Results: The Klebsiella pneumoniae strains showed susceptibility to imipenem and amikacin ( 94.3%) ,chloramphenicol (88.5%) , gentamicin (81.1%) , ciprofloxacin (80.3%) , cefepime (73%) ,streptomycin (72.1%), nalidixic acid (68%) , tetracycline (65.6%), and cefotaxime, ceftazidime, cefpodoxime (62.3%) . The resistance of strains was seen to nitrofurantoin (53.3%), cotrimoxazole (39.3%), Cefpodoxime (37.7%), cefotaxime (36.9%), ceftriaxone (36.1%), aztreonam (34.4%), ceftazidime (32.8%). Thirty-eight isolates (31.1%) were shown to produce ESBLs. Conclusion: A high rate of resistance was observed to most of the antibiotics among ESBL producing strains therefore, it is important to be careful about the use of antibiotics and identification of ESBL using phenotypic methods. Keywords: Antibiotic Resistance, Extended Spectrum Beta-Lactamases,KlebsiellaPneumoniae, Urinary Tract Infection, Isolate
Shahram Shahraki Zahedani , Rogaye Javadi ,
Volume 12, Issue 2 (Mar-Apr 2018)
Abstract
ABSTRACT
Background and Objectives: Acinetobacter baumannii is an opportunistic pathogen associated with nosocomial infections. Treatment of infections caused by this bacterium has become challenging due to increasing rate of resistance to a wide range of antibiotics such as carbapenems. One of the main mechanisms of resistance to carbapenems is the production of carbapenemase. The objective of this study was to evaluate antibiotic resistance patterns and frequency of carbapenemase-producing A. baumannii strains using the CarbAcineto NP Test.
Methods: In this descriptive cross-sectional study, 130 A. baumannii isolates were collected from clinical specimens of teaching hospitals in Zahedan in 2016. After determining the antibiotic resistance patterns, all A. baumannii isolates were examined using the phenotypic method of CarbAcineto NP test to evaluate production of carbapenemase enzymes.
Results: Based on the antibiogram results, more than 90% of the isolates were resistant to the antibiotics tested in this study. However, the lowest rate of resistance was observed against colistin, minocycline, tigecycline and doxycycline, respectively. Based on the results of the CarbAcineto NP test, 96% of carbapenem-resistant strains were positive for the production of carbapenemases.
Conclusion: Due to the high resistance of A. baumannii to carbapenems, they are not currently suitable for the treatment of infections caused by this bacterium. However, since most carbapenem-resistant strains are susceptible to colistin, minocycline, tigecycline, and doxycycline, these antibiotics or their combination are recommended for the treatment of the infections caused by the resistant strains. Rapid identification of carbapenemase-producing bacteria using efficient methods such as CarbAcineto NP test is essential to prevent their spread, particularly in hospitals.
KEYWORDS: Acinetobacter baumannii, Carbapenemase, CarbAcinetoNP Test.
Shahram Shahraki Zahedani , Nasrin Sayadzai,
Volume 12, Issue 2 (Mar-Apr 2018)
Abstract
ABSTRACT
Background and Objectives: Diarrheagenic Escherichia coli (DEC) pathotypes are important causes of diarrhea among children in developing countries. The objective of this study was to determine the frequency and antibiotic resistance pattern of DEC pathotypes in children aged less than 10 years.
Methods: This cross-sectional study was done on 300 E. coli strains isolated from diarrheic stool samples of children aged less than 10 years who were admitted to hospitals and central laboratory in Zahedan, between July and October 2016. DEC pathotypes were identified by standard biochemical testing and phenotypic testing using polyvalent antiserums. Antibiotic resistant pattern of these strains was evaluated against 11 different antibiotics by the agar disk diffusion method according to the Clinical and Laboratory Standards Institute guidelines.
Results: Of the 300 E. coli isolates, 89 (29.6%) were found positive for DEC using polyvalent antiserums. In this study, 35 cases (39.3%) reacted with antiserum 1, 21 cases (25.8%) reacted with the antiserum 2, and 31 cases (34.8%) reacted with antiserum 3. The highest rate of resistance was observed against ampicillin (94.8%), tetracycline (87.2%), and co-trimoxazole (70.5%). In addition, the lowest rate of resistance was related to imipenem (1%) and ciprofloxacin (8.9%).
Conclusion: DEC pathotypes are the important causes of diarrhea among children admitted to hospitals of Zahedan. Considering the high rate of antibiotic resistance among these pathotypes in this region, prescription of antibiotics should be based on accurate detection of these strains.
Keywords: Escherichia coli, Child, Antibiotic Resistance.
Mohammad Bokaeian, Shahram Shahraki Zahedani , Abbasali Delarampoor, Mohammadreza Atashgah, Bahram Dahmarde ,
Volume 12, Issue 3 (May-Jun 2018)
Abstract
ABSTRACT
Background and Objectives: The resistance of gram-negative bacteria to antibiotics has become a serious problem, which imposes a significant increase in treatment costs. Klebsiella pneumoniae is an important nosocomial pathogen from the Enterobacteriaceae family. The aim of this study was to investigate the frequency and pattern of antibiotic resistance in K. pneumoniae strains isolated from clinical samples.
Methods: This descriptive, cross-sectional study was performed on 150 K. pneumonia strains isolated from different clinical samples such as urine, sputum, blood, ulcers, lung secretions and abdominal abscess. Antibiogram test was performed using the disk diffusion method (Kirby-Bauer). Minimum inhibitory concentration of amikacin, tobramycin and gentamicin was determined via the E-test for 50 strains with high resistance rates.
Results: In this study, the highest rate of resistance was observed against carbenicilin, ceftriaxone, cefepime and streptomycin. K. pneumonia isolates were most frequent in urine and sputum samples. In the E-test, the highest rate of resistance was observed against gentamicin, tobramycin (16µg/ml) and amikacin (64µg/ml).
Conclusion: Based on our results, tigecycline, netilmicin, kanamycin and amikacin are the most effective antibiotics for the treatment of K. pneumoniae infections.
Keywords: Klebsiella pneumoniae, antimicrobial resistance, E-test method
Mansour Dabirzadeh , Reza Shahraki , Mohammadreza Beheshtizadeh , Mahdi Khoshsima Shahraki,
Volume 20, Issue 2 (Mar-Apr 2026)
Abstract
Background: Cryptosporidium is one of the most important protozoan parasites causing waterborne diseases worldwide. The parasite’s oocysts are resistant to conventional water treatment, making molecular detection crucial for identifying contamination sources.
Methods: A total of water samples were collected from different sites in Zabol and Zahedan, southeastern Iran. Microscopic screening was performed after concentration and staining with modified Ziehl-Neelsen and Trichrome methods under 1000× oil-immersion magnification. DNA was extracted from positive samples, and the SSU rRNA gene (~800-900 bp) was amplified by PCR. The resulting products were subjected to enzymatic digestion using AluI and RsaI restriction enzymes, and representative amplicons were sequenced.
Results: Microscopic examination confirmed the presence of Cryptosporidium oocysts in several water samples. PCR amplification successfully produced fragments of the expected size without nonspecific bands. AluI digestion revealed distinct fragment patterns consistent with Cryptosporidium spp., while RsaI showed no cutting sites. Sequence analysis through BLAST showed high identity (≥99%) with C. parvum isolates. The phylogenetic tree constructed using the BLAST distance-tree method grouped the sequence closely with C. parvum, confirming its identity.
Conclusion: Molecular characterization of Cryptosporidium from water samples in southeastern Iran indicated contamination primarily with C. parvum. These findings emphasize the necessity of continuous molecular surveillance to ensure the safety of drinking and recreational waters in the region.