Detection of Salmonella typhi by polymerase chain reaction: Implications in diagnosis of typhoid fever

The diagnosis of typhoid fever currently depends on isolation of Salmonella Typhi from blood. The sensitivity of blood culture is very low due to prior antibiotic treatment which is a common practice in Bangladesh. The sensitivity of blood culture also decreases at later stage of the disease. Widal test is the most utilized test in Bangladesh next to blood culture because it is inexpensive, less invasive. But the result of the test is controversial due to false negative & false positive results in some cases. In this study, a recently introduced polymerase chain reaction-based technique (which has 100% specificity for S. Typhi) was compared with widal test among 80 clinically suspected typhoid fever cases. Among 80 cases, the respective figures of positivity for PCR & widal test were 70% & 43.75% respectively. It can be concluded that PCR based technique is more sensitive & much superior to widal for diagnosis of typhoid fever. DOI: http://dx.doi.org/10.3329/bjpp.v30i2.22683 Bangladesh J Physiol Pharmacol 2014; 30(2): 46-50

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Detection of Salmonella typhi in the blood of patients with typhoid fever by polymerase chain reaction.

Journal of Clinical Microbiology ◽

10.1128/jcm.31.6.1439-1443.1993 ◽

1993 ◽

Vol 31 (6) ◽

pp. 1439-1443 ◽

Cited By ~ 87

Author(s):

J H Song ◽

H Cho ◽

M Y Park ◽

D S Na ◽

H B Moon ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Typhoid Fever ◽

Salmonella Typhi ◽

Chain Reaction ◽

Polymerase Chain

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Enhanced detection rate of typhoid fever among clinically suspected patients in a tertiary referral hospital in Dhaka, Bangladesh using nested polymerase chain reaction technology

Bangladesh Medical Research Council Bulletin ◽

10.3329/bmrcb.v41i3.29971 ◽

2016 ◽

Vol 41 (3) ◽

pp. 138-143

Author(s):

Shafinaz Khan ◽

Ruhul Amin Mia ◽

Sumaiya Khatun

Keyword(s):

Polymerase Chain Reaction ◽

Blood Culture ◽

Typhoid Fever ◽

Nested Pcr ◽

Salmonella Typhi ◽

Chain Reaction ◽

Tertiary Referral Hospital ◽

Nested Polymerase Chain Reaction ◽

Polymerase Chain ◽

Pcr Targeting

A nested polymerase chain reaction (PCR) specific for Salmonella enterica subspecies enteric serovar Typhi was used for the detection of the pathogen in blood. This study was done during the period of March 2013 to February 2014. A total of 80 clinically suspected cases of typhoid fever were included in the study. Blood was collected from all participating individuals. Nested PCR targeting the flagellin gene (fliC) of Salmonella Typhi & blood culture were done for each of the cases. The positivity rate of PCR & blood culture was 70%& 20% respectively. The positivity rate of PCR was significantly higher than blood culture (P< 0.05). With the nested PCR, S. Typhi DNAs were detected from blood specimens of 67.2% (43/64) patients among the suspected typhoid fever cases on the basis of clinical features but with negative cultures. We conclude that the PCR technique could be used as a novel diagnostic method of typhoid fever, particularly in culture-negative cases in an endemic country like Bangladesh.

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DETEKSI BAKTERI PENYEBAB PENYAKIT TYPHUS PADA MANUSIA DENGAN POLYMERASE CHAIN REACTION

JRSKT - Jurnal Riset Sains dan Kimia Terapan ◽

10.21009/jrskt.011.08 ◽

2011 ◽

Vol 1 (1) ◽

pp. 45

Author(s):

Muktiningsih Nurjayadi ◽

Fera Kurnia Dewi ◽

Dahlia Dahlia ◽

S, Restu.N S ◽

Fitri W

Keyword(s):

Polymerase Chain Reaction ◽

Detection Method ◽

Serological Test ◽

Research Result ◽

Salmonella Typhi ◽

Detection Methods ◽

Chain Reaction ◽

Specificity And Sensitivity ◽

Dna Fragment ◽

Polymerase Chain

Salmonella typhi is bacteria that cause typhoid disease in humans. In Indonesia, the morbidity number of typhoid disease tends to be increase. Thus, it has been requiring the alternative for handling or preventing that disease. Recently, the detection method commonly uses for S. typhi detection is Serological test. The weakness of this method is often producing less accurate and not specific detection. The previous research was successfully discovered S. typhi gene that codes protein which is contributed at adherents or colonization those bacteria in epithelial human cell. That result was base to develop detection on S. typhi method by Polymerase chain reaction (PCR). The aim of this research is developing a specific and accurate detection method for S. typhi bacteria by PCR. The research result is performed successfully to amplify the fimbrial-C S. typhi gene using pairs of primer FW-INT 2- REV-1A NEW which was designed and synthesized in previous step. That success showed by the finding of the DNA fragment of 0.2 kilobase (kb) proffers to size of DNA fragment which is hopefully in using S. typhi genome as a template. Specificity and sensitivity test for those primers are still conducting to reproducibility results. Base on the results can be concluded that the research have successfully conducted in developing S. typhi detection method using pairs of S. typhi fimbrial-C primer. Hopefully, the studied of developing detection methods was conducted better compare with former detection methods.Keywords: S. typhi detection method, fim-C S. typhi gene, PCRAbstrakSalmonella typhi merupakan bakteri penyebab penyakit tifus pada manusia. Di Indonesia, angka morbiditas penderita penyakit typhus cenderung meningkat, sehingga diperlukan suatu alternatif untuk penanganan atau pencegahan penyakit tersebut. Sampai saat ini metode deteksi S. typhi yang banyak digunakan adalah uji serologi. Kelemahan metode ini adalah sering menghasilkan deteksi yang kurang akurat dan tidak spesifik. Pada penelitian yang dilakukan sebelumnya, telah berhasil ditemukan gen fimbrial-C S. typhi pengkode protein yang berperan dalam penempelan S. typhi pada usus manusia, hasil ini dijadikan landasan untuk pengembangan metode deteksi menggunakan teknik PCR. Tujuan penelitian ini mengembangkan metode deteksi yang akurat dan spesifik untuk bakteri penyebab penyakit typhus pada manusia. Hasil penelitian menunjukkan bahwa telah berhasil dilakukan amplifikasi gen fimbrial-C S. typhi menggunakan pasangan primer hasil perancangan yaitu FW-INT 2- REV-1A NEW. Keberhasilan tersebut ditunjukkan dengan diperolehnya pita DNA berukuran 0.2 kilo basa (kb) sesuai dengan ukuran pita DNA yang diharapkan dengan menggunakan template DNA genom bakteri S. typhi. Uji sensitivitas dan spesifisitas terhadap primer hasil rancangan sedang di kaji lebih lanjut untuk memperoleh reprodusibiltas hasil pengujian. Berdasarkan hasil yang diperoleh dapat disimpulkan bahwa telah berhasil dilakukan pengembangan metode deteksi S. typhi menggunakan pasangan primer fimbrial-C S. typhi. Pengkajian pengembangan metode deteksi yang dihasilkan ini diharapkan dapat lebih baik dibanding beberapa metode deteksi yang sudah ada.Kata Kunci: Metode Deteksi Bakteri typhus, fim-C S. typhi, PCR

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The comparison of cultures, widal agglutination test and polymerase chain reaction as a diagnostic tool in typhoid fever

Open Medicine ◽

10.2478/s11536-008-0052-8 ◽

2008 ◽

Vol 3 (4) ◽

pp. 470-474 ◽

Cited By ~ 1

Author(s):

Ilker Devrim ◽

Koray Ergünay ◽

Ates Kara ◽

Hasan Tezer ◽

Inci Yiğitkanl ◽

...

Keyword(s):

Polymerase Chain Reaction ◽

Typhoid Fever ◽

Enteric Fever ◽

Antimicrobial Agents ◽

Blood Cultures ◽

Chain Reaction ◽

Specific Test ◽

Salmonella Infections ◽

Group I ◽

Polymerase Chain

AbstractTyphoid fever caused by Salmonella typhi, paratyphi A and B, is an important cause of morbidity and mortality in many developing countries. A rapid and sensitive method for the detection of S. typhi is essential for early diagnosis of typhoid fever and effective therapy. In this study 45 febrile patients who were suspected to have enteric fever were enrolled, and the results of blood cultures, widal agglutination tests and Polymerase Chain Reaction in these cases were evaluated. Group I consisted of 11 patients with diseases other than salmonella infections, group II represented 6 patients with positive cultures, and group III represented 28 patients with negative blood cultures negative but who were clinically suspected cases that had a medical history of using variable antimicrobial agents. Two positive PCR results were present; one of them was in culture positive group (16,6%) and the other was in culture negative group (3,5%). In our study widal agglutination tests and cultures were found not to be helpful in differential dignosis. Although PCR based detection of S. typhi is reported to be a sensitive and specific test for the diagnosis of enteric fever, in our study the benefit of this method in the diagnosis of especially patients who were treated with antimicrobial therapy was not clearly determined. Other methods to increase sensitiviy and specificity to levels such as those of real time PCR should be developed and large-scaled studies should be done in endemic and non-epidemic regions.

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