Microbiology
Khashayar Mohseni; Reza Mirnejad; Vahab Piranfar; Shiva Mirkalantari
Abstract
Background & Objective: Since the symptoms of Brucellosis are often atypical and nonspecific, using clinical signs alone to diagnose brucellosis is not advised; therefore, the diagnosis relies predominantly on laboratory testing. Currently, molecular, serological, and microbiological methods are ...
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Background & Objective: Since the symptoms of Brucellosis are often atypical and nonspecific, using clinical signs alone to diagnose brucellosis is not advised; therefore, the diagnosis relies predominantly on laboratory testing. Currently, molecular, serological, and microbiological methods are used for diagnosis of this disease. In this study we examined ELISA, PCR and serum agglutination (SAT) methods on human patient serum samples. Methods:A total of 100 serum samples were collected from suspected patients. Fifty serum samples gave a positive result with the Wright test. The ELISA method was first employed on all samples for the detection of IgG and IgM antibodies against Brucella. Subsequently, the rapid PCR methodology was used to identify presence of Brucella genome in 500 µL of each serum sample. The B4/B5 primer pair was used for PCR amplification. Results:Out of the 100 serum samples obtained from patients with suspected brucellosis, 50 samples tested positive by SAT and displayed high titers of 1/160. Of these 50 positive samples, 49 samples were positive as per the ELISA test whereas one sample tested negative. The PCR test was conducted on all 100 serum samples and results showed that the 45 serum samples that gave a positive agglutination test were also positive by PCR. Conclusions: Various laboratory methods have beenused or introduced for the detection of Brucella. Molecular methods such as PCR, a rapid and sensitive method for detection of bacteria, have also been reported. Based on the results of this study, we propose that the simultaneous use of serology and molecular techniques has the potential to overcome limitations of detection thereby enabling the selection of appropriate treatment for the patient.
Microbiology
Faramarz Masjedian Jazi; Gholamreza Irajian; Reza Mirnejad; Vahhab Piranfar; Taghi zahraei salehi; Noor Amir Mozafari; Ehsanollah Ghaznavi-rad; Mahmoud Khormali
Volume 11, Issue 3 , July 2016, , Pages 238-247
Abstract
Background: Brucellosis is an endemic zoonotic disease in the Middle East. This study intended to design a uniplex PCR assay for the detection and differentiation of Brucella at the species level and determining the antibiotic susceptibility pattern of Brucella in Iran. Methods: Sixty-eight Brucella ...
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Background: Brucellosis is an endemic zoonotic disease in the Middle East. This study intended to design a uniplex PCR assay for the detection and differentiation of Brucella at the species level and determining the antibiotic susceptibility pattern of Brucella in Iran. Methods: Sixty-eight Brucella specimens (38 animal and 30 human specimens) were analyzed using PCR (using one pair of primers). Antibiotic susceptibility patterns were evaluated and compared using the E-Test and disk diffusion susceptibility test. Tigecycline susceptibility pattern was compared with other antibiotics. Results: Thirty six isolates of B. melitensis, 2 isolates of B. abortus and 1 isolate of B. suis from the 38 animal specimens, 24 isolates of B. melitensis and 6 isolates of B. abortus from the 30 human specimens were differentiated. The MIC50 values of doxycycline for human and animal specimens were 125 and 10 μg/ml, respectively, tigecycline 0.064 μg/ml for human specimens and 0.125μg/ml for animal specimens, and trimethoprim/ sulfamethoxazole and ciprofloxacin 0.065 and 0.125μg/ml, respectively, for both human and animal specimens. The highest MIC50 value of streptomycin in the human specimens was 0.5μg/ml and 1μg/ml for the animal specimens. The greatest resistance shown was to tetracycline and gentamicin, respectively. Conclusion: Uniplex PCR for the detection and differentiation of Brucella at the strain level is faster and less expensive than multiplex PCR, and the antibiotics doxycycline, rifampin, trimethoprim-sulfamethoxazole, ciprofloxacin, and ofloxacin are the most effective antibiotics for treating brucellosis. Resistance to tigecycline is increasing, and we recommend that it be used in a combination regimen.
