عنوان المقالة:In Term of Molecular Technique, Taxonomic and Diagnostic Aspects of Chronic Human Brucellosis in Ramadi City In Term of Molecular Technique, Taxonomic and Diagnostic Aspects of Chronic Human Brucellosis in Ramadi City
Ban H. K. Al- Khater, Dr. Mushtak T. S. Al- Ouqaili, Dr. Salah N. Al- Anii
الملخص الانجليزي
Background: The diagnosis of chronic brucellosis is frequently difficult to establish. The disease may clinically mimic any infectious and noninfectious disease. This study has been laid down to evaluate PCR technique in the diagnosis of chronic brucellosis in comparison to conventional techniques.Patients and methods:- One Hundred Forty Four peripheral blood samples obtained from tow group: one hundred twenty four samples from patients with highly suspicion brucellosis and twenty samples from healthy volunteers. The samples were tested by serology using Rose Bengal test (RBT), serum agglutination test (SAT) and 2- Mercapto-ethanol. Blood culture using monophasic blood culture technique, Castaneda biphasic blood culture technique and lysis centrifugation blood culture method. Also, the samples submitted to polymerase chain reaction using primer sets (B4 and B5) to amplify a 223- bp region coding for 31- kDa Brucella antigen was achieved. Furthermore all positive PCR samples were submitted to PCR cocktail to differentiate Brucella species.Results:- Out of 124 (86.1%) blood samples from patients with chronic brucellosis, 36 (29.03%) showed strong positive for RBT. On the other hand, 61 (49.2%) cases were positive when SAT≥1/320, 104 (83.9%) cases revealed positive results when the SAT titer ≥1/160 and 118 (95.2%) represented positive cases when SAT titer ≥1/80. Also all blood samples submitted to mono and biphasic blood culture technique were 50 (40.3%) and 64 (51.6%) represented positive results respectively, while only 40 blood samples were submitted to lysis centrifugation blood culture technique, 35 (87.5%) revealed positive results. Also, 103 (83.1%) showed positive results for PCR. Out of these cases, 77 (74.8%) represented positive results (B. melitensis), while 26 (25.2%) showed negative cases. Finally, among the twenty (13.9%) controls, serological test, blood culture and PCR were negative.Conclusions:- The study suggested that combination of Rose Bengal test and serum agglutination test ensured the diagnosis of brucellosis. Also Castaneda biphasic blood culture method had improved the rate of isolation and reduce the period of incubation. Further, lysis centrifugation blood culture technique showed increase in the rate of isolation especially in chronic stage. On the other hand, the current study suggested that PCR has several advantages over the conventional methods for the diagnosis of human brucellosis such as speed, safety, high sensitivity and specificity. Furthermore, PCR is very specific and highly sensitive technique that can be used not only for detection of Brucella antigen in any stage of the disease but also in differentiating Brucella species by using PCR cocktail which used different sets of primers.
الأستاذ الدكتور مشتاق طالب صالح الندا | Dr. Mushtak T. S. Al-Neda | 7971