Comparative genomic analysis of Tropheryma whipplei strains reveals that diversity among clinical isolates is mainly related to the WiSP proteins.
(1/41)
BACKGROUND: The aim of this study was to analyze the genomic diversity of several Tropheryma whipplei strains by microarray-based comparative genomic hybridization. Fifteen clinical isolates originating from biopsy samples recovered from different countries were compared with the T. whipplei Twist strain. For each isolate, the genes were defined as either present or absent/divergent using the GACK analysis software. Genomic changes were then further characterized by PCR and sequencing. RESULTS: The results revealed a limited genetic variation among the T. whipplei isolates, with at most 2.24% of the probes exhibiting differential hybridization against the Twist strain. The main variation was found in genes encoding the WiSP membrane protein family. This work also demonstrated a 19.2 kb-pair deletion within the T. whipplei DIG15 strain. This deletion occurs in the same region as the previously described large genomic rearrangement between Twist and TW08/27. Thus, this can be considered as a major hot-spot for intra-specific T. whipplei differentiation. Analysis of this deleted region confirmed the role of WND domains in generating T. whipplei diversity. CONCLUSION: This work provides the first comprehensive genomic comparison of several T. whipplei isolates. It reveals that clinical isolates originating from various geographic and biological sources exhibit a high conservation rate, indicating that T. whipplei rarely interacts with exogenous DNA. Remarkably, frequent inter-strain variations were dicovered that affected members of the WiSP family. (+info)
Genotyping reveals a wide heterogeneity of Tropheryma whipplei.
(2/41)
Value of Tropheryma whipplei quantitative polymerase chain reaction assay for the diagnosis of Whipple disease: usefulness of saliva and stool specimens for first-line screening.
(6/41)
Whipple's disease: easily diagnosed, if considered.
(7/41)
Patients present with arthralgia, abdominal pain, diarrhoea and weight loss. The disease is commonly diagnosed by histological examination of small bowel biopsies, especially after staining with periodic acid-Schiff. Because of the rarity of the disease, its diagnosis is not often considered. Therefore the necessary investigations might be omitted. This case report might serve as a reminder for internists or gastroenterologists to consider Whipple's disease in patients with abdominal, articular or other symptoms after having excluded common differentials. We also review the current literature on Whipple's disease. Whipple's disease is an infectious disorder caused by Tropheryma whipplei. (+info)
Fourteen years of severe arthralgia in a man without gastrointestinal symptoms: atypical Whipple's disease.
(8/41)