Detection and differentiation of Bartonella henselae and Bartonella quintana DNA
Bacteria of the genus Bartonella are fastidious, gram-negative, slow-growing microorganisms. Eight species of the genus Bartonella are currently recognized as pathogenic agents in human diseases. Clinical syndromes include trench fever, Carrion’s disease, bacillary angiomatosis, bacillary peliosis, endocarditis, cat scratch disease, neuroretinitis, and asymptomatic bacteremia. The two species most often encountered in human infection are B. henselae and B. quintana. B. henselae is considered the causative agent of cat scratch disease, which is characterized by lymphadenopathy preceded by an erythematous papule at the inoculation site. 30% of patients have low-grade fever and malaise. Infection with B. henselae can range from lymphadenopathy to systemic disease, and the severity and presentation are often related to immune status. Immunocompromised patients often present with systemic disease. B. quintana is the causative agent of trench fever, typically characterized by a sudden onset of prolonged chills and fever. B. henselae and B. quintana are both causative agents of cutaneous bacillary angiomatosis, which is the most common clinical manifestation in immunocompromised patients but can also occur in immunocompotent patients. It is characterized by various presentations of cutaneous or subcutaneous vascular lesions, lymphadenopathy, and often, abdominal symptoms. Lesions may be located anywhere on the body and may be clinically and histologically similar to Kaposi’s sarcoma (Mandell GL, et al, 2004).
Sequencing of specific gene(s) provides a rapid and accurate identification of clinically significant organism. Judicious primer selection allows amplification of sequences at the species level or at the phylogenetic level. Raw sequences are assembled then classified by comparison to public sequence databases and the UWMC Clinical Microbiology Sequence Database in order to provide organism identification.
16S rRNA gene sequencing is considered by current taxonomists to be the gold standard in bacterial identification and classification. It contains conserved regions useful for the design of universal primers that amplify the gene from all pathogenic and nonpathogenic bacteria in addition to hypervariable regions that contain species-specific signature sequences useful for bacterial identification to species level.
The biosynthesis pathway for riboflavin (vitamin B2) is present in bacteria and plants but is absent in vertebrates. Riboflavin synthetase, encoded by ribC, is highly conserved at the species level. Primer oligonucleotides designed on the basis of localized differences within the ribC DNA region are used in species-specific assays for the differentiation of B. henselae and B. quintana, the two most commonly isolated Bartonella species. This assay, in addition to 16S rRNA gene increases the diagnostic potential to detect and differentiate Bartonella species.
Code | Name |
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BRTSUM | Bartonella PCR: Summary |
BR16RS | Bartonella PCR: Detection, 16S rDNA |
BR16ID | Bartonella PCR: Identification, 16S rDNA |
BRRCRS | Bartonella PCR: Detection, ribC |
BRRCID | Bartonella PCR: Identification, ribC |
BRTSI | Bartonella PCR: Specimen Description |
BRTSPI | Bartonella PCR: External Identifier |
BRTSR | Bartonella PCR: Special Requests |
BRTSC | Bartonella PCR: Specimen Comments |
BRTNAE | Bartonella PCR: Specimen DNA Extraction |
BRTREV | Bartonella PCR: Pathologist Review |
BRTME | Bartonella PCR: Method Note |
DNA extraction, nucleic acid purification, polymerase chain reaction (PCR), sequencing
Acceptable specimens are listed below. Please see Molecular Microbiology Specimen Submission for complete specimen collection and handling instructions.
Shipping/Handling
Acceptable Specimens
*Mycobacterium avium complex DNA Detection [MAVDNA] can be ordered on sputum
**Fungal PCR reflex NGS [FUNDNA] and Fungal DNA Detection by PCR (without reflex to NGS) [NRFDNA] may have interference due to some lots of eSwabs which have been found to contain Saccharomyces cerevisiae DNA, resulting in false positive detection. Clinical correlation and/or retesting with a different collection method is advised. The detection of S. cerevisiae from eSwab specimens can interfere with our ability to rule out other fungal DNA.
Unacceptable Specimens
Optimal Quantity:
Please note: We do not need a separate specimen aliquot for each test ordered. Only a single specimen aliquot or block of optimal quantity is necessary for performing multiple tests. If multiple aliquots or blocks of optimal quantity are sent, up to 2 will be pooled.
Fresh tissue is the optimal specimen of choice, as it reduces the chance of introducing exogenous DNA templates or microorganisms during embedding/fixation. Formalin fixation dramatically reduces the sensitivity of the assays due to reduced template yield and quality.
Please see Molecular Microbiology Specimen Submission for complete specimen collection and handling instructions.
UWMC/HMC: Store and send fresh tissue/fluid specimens refrigerated, if specimen storage and transport will exceed 8 hours, freeze at -20°C. Freeze all fresh tissue/fluid specimens at -20°C upon arrival in UW Molecular Microbiology.
UW-MT |
Microbiology, Molecular Diagnostics
206-520-4600 ---------------------------------------- Shipping Address Attn: Molecular Microbiology Performing Lab Address Clinical Microbiology Lab, NW177 |
Contact Information Please e-mail us with any questions or comments you may have. Your inquiry will be answered as soon as possible. email: molmicdx@uw.edu The Molecular Microbiology lab is open from Monday-Friday, 7am-4pm PDT. Billing inquiries and requests for faxed reports can be made to our Client Services Department at (206) 520-4600 or (800) 713-5198. For results or other inquiries, we can be reached by phone at the following numbers:
For assistance during weekends, holidays and after hours, please contact Lab Medicine Resident at (206) 598-6190 |
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