Diagnosis of Human Brucellosis by Blood Culture (BACTEC) and PCR Method via Whole Blood and Serum

Abstract

Background: Brucellosis is the most common global zoonosis and an important public health problem in many parts of the world including Iran. Diagnosis of brucellosis is frequently difficult to establish and conventional methods are not always successful in identifying the organisms. Rapid detection of Brucella species by an automated blood culture system and Polymerase Chain Reaction (PCR) may lead to an earlier diagnosis and may improve patient management..Objectives: The current study aimed to evaluate PCR technique as a diagnostic tool for brucellosis in comparison to conventional bacteriological techniques..Materials and Methods: A total of 50 patients suspected to have brucellosis were included in this study. All patients presented clinical signs compatible with brucellosis. Diagnosis was established by detecting a titer equal to or greater than 1:160 by the standard tube agglutination (STA) method. Blood samples and sera from the patients were tested by culture using BACTEC 9050 system and PCR using primer set to amplify a 223 bp region with in the gene coding for a 31 KD Brucella antigen..Results: Eleven (22%) whole blood samples and 17 (34%) serum samples out of 50 had positive PCR and 7 (14%) patients had Brucella species grown in their cultures. Out of 43 blood culture negative samples, 10 (23.3 %) were positive with the serum PCR versus in 4(9.3 %) with whole blood PCR..Conclusions: The results suggest that the serum PCR assay is rapid and easy to perform and highly sensitive and specific, and it may therefore be considered a useful tool for diagnosis of human brucellosis

Blood Culture Bottle and Standard Culture Bottle Methods for Detection of Bacterial Pathogens in Parapneumonic Pleural Effusion

“…Blood culture bottles were used for aerobic organisms because aerobic organisms are the common pathogens in bacterial PPE ( 8 ), and patients with pleural effusion from anaerobic pathogens were excluded. The blood culture bottles were incubated in BacT/Alert system at 35°C for seven days ( 15 , 16 ), and the procedures for BacT/Alert system were followed ( 16 ), while pleural fluids in the standard culture bottles or sterile tubes were cultured using blood, MacConkey, and chocolate media. The organism identification procedures were similar in both groups of bottles.…”

Pediatric brucellosis

“… 43 , 51 A study comparing the blood culture Bactec system and whole blood and serum PCR method determined that both methods (whole blood and serum PCR) were similarly sensitive and specific for diagnosing human brucellosis. 52 In another study, the specificity and sensitivity of SAT, Coombs Wright test, 2-mercaptoethanol test (2ME), ELISA (IgG and IgM), and PCR were compared using serum samples. Among the applied methods of diagnosis, the SAT displayed the lowest positivity rate and ELISA test had the highest efficiency.…”

A novel multi-epitope recombined protein for diagnosis of human brucellosis

“…Blood culture, which was considered the golden standard method, provides the definitive diagnosis of brucellosis but may not provide a positive result for all patients [ 6 ]; it presents several other drawbacks, such as being time-consuming and dangerous for personnel, and few laboratories have suitable culture conditions [ 7 ]. Although polymerase chain reaction (PCR) and real-time PCR assays are very promising, infrastructure, equipment, and expertise are lacking in developing countries [ 8 ].Therefore, serological tests, such as the enzyme-linked immunosorbent assay (ELISA) and standard tube agglutination test (SAT), have become the most useful tools for diagnosis of brucellosis. In particular, ELISA can provide higher sensitivity and specificity compared with SAT [ 9 ].…”