K Nilsson1, A Liu, C Påhlson, O Lindquist. 1. Section of Infectious Diseases, Department of Medical Sciences, Uppsala University Hospital, SE-751 85 Uppsala, Sweden. knf@tele2.se
Abstract
OBJECTIVES: Rickettsiae, which causes vasculitis, has not been linked to atherosclerotic cardiovascular disease in contrast to Chlamydia pneumoniae whose association with coronary artery disease and with sclerotic heart valves in patients undergoing aortic valve replacement is well established, even if causality is yet to unproven. In the search for any of these infectious agents, 84 pathological and 15 normal aortic heart valves of patients undergoing forensic autopsy were analysed by PCR and DNA-sequencing. METHODS: Two to four pieces of all valves were examined by semi-nested PCR, with primers specific for 16S rDNA, citrate synthase (gltA) and 17 kDa outer membrane protein (OMP) genes. RESULTS: Genetic material from Rickettsia spp. and C. pneumoniae was found in 17 (20.2%) and 22 (26.2%), respectively, of the 84 pathological aortic valves. In 35 (41.7%) of these 84 valves either C. pneumoniae or Rickettsia spp. were detected by PCR and in six cases (7.1%) these two organisms co-existed. In one case with Lambl's excrescences, previously considered as aseptic, presence of rickettsia-like organisms also was demonstrated by light microscopy, immunohistochemistry and sequencing of the amplified PCR product showing 100% homology with the published sequence for R. helvetica. In three of the 15 control valves, genetic material from only C. pneumoniae was detected compared to Rickettsia spp. that was significantly detected only in the pathological valves (Fisher's Exact test, 1-sided p = 0.046). CONCLUSIONS: The findings suggest that Rickettsia spp. also have a role in the pathogenesis of aortic valve disease.
OBJECTIVES: Rickettsiae, which causes vasculitis, has not been linked to atherosclerotic cardiovascular disease in contrast to Chlamydia pneumoniae whose association with coronary artery disease and with sclerotic heart valves in patients undergoing aortic valve replacement is well established, even if causality is yet to unproven. In the search for any of these infectious agents, 84 pathological and 15 normal aortic heart valves of patients undergoing forensic autopsy were analysed by PCR and DNA-sequencing. METHODS: Two to four pieces of all valves were examined by semi-nested PCR, with primers specific for 16S rDNA, citrate synthase (gltA) and 17 kDa outer membrane protein (OMP) genes. RESULTS: Genetic material from Rickettsia spp. and C. pneumoniae was found in 17 (20.2%) and 22 (26.2%), respectively, of the 84 pathological aortic valves. In 35 (41.7%) of these 84 valves either C. pneumoniae or Rickettsia spp. were detected by PCR and in six cases (7.1%) these two organisms co-existed. In one case with Lambl's excrescences, previously considered as aseptic, presence of rickettsia-like organisms also was demonstrated by light microscopy, immunohistochemistry and sequencing of the amplified PCR product showing 100% homology with the published sequence for R. helvetica. In three of the 15 control valves, genetic material from only C. pneumoniae was detected compared to Rickettsia spp. that was significantly detected only in the pathological valves (Fisher's Exact test, 1-sided p = 0.046). CONCLUSIONS: The findings suggest that Rickettsia spp. also have a role in the pathogenesis of aortic valve disease.
Authors: Felicitas S Boretti; Andrea Perreten; Marina L Meli; Valentino Cattori; Barbara Willi; Nicole Wengi; Sándor Hornok; Hanspeter Honegger; Daniel Hegglin; Roman Woelfel; Claudia E Reusch; Hans Lutz; Regina Hofmann-Lehmann Journal: Appl Environ Microbiol Date: 2009-03-27 Impact factor: 4.792
Authors: Ellen Tijsse-Klasen; Manoj Fonville; Fedor Gassner; Ard M Nijhof; Emil K E Hovius; Frans Jongejan; Willem Takken; Johan R Reimerink; Paul A M Overgaauw; Hein Sprong Journal: Parasit Vectors Date: 2011-04-18 Impact factor: 3.876