Bartonella bacilliformis is a haemotrophic bacterium which was first isolated in 1909 by the Peruvian physician Albert Barton. It causes a unique clinical syndrome known as Bartonellosis or Carrion’s disease, a disease which causes death of more 7000 people in Peru in the year 1871.
B. bacilliformis is a Gram negative nonsporeforming coccobacillus mostly observed in Write-stained blood smears where it appears an intense purple rods or cocci. It divides by binary fission. B. bacilliformis has a thin cell wall and has a double membrane. Culture forms of B. bacilliformis have flagella at one pole .They grows at a temperature of 28oC and a pH of 7.8. They are translucent and vary in size from minute to 1-2 mm in diameter. They are susceptible to the action of pencillin, streptomycin, chloramphenicol, tetracycline and erythromycin.
B. bacilliformis enters the bloodstream of humans through the bite of a female sand fly, Phlebotomus verrucarum (Kreier and Ristic, 1981; Hertig, 1942). This sand fly is mainly found in the western Andes of the South American countries of Peru, Ecuador and Columbia where the temperature and humidity conditions are favorable for their survival. Thus bartonellosis is restricted to these areas. Bartonellosis is a biphasic disease acquired only by humans. Bartonellosis causes two distinct clinical syndromes: Oroya fever and Verruga peruana. Oroya fever is the primary, acute phase characterized by fever, malaise, and severe intravascular hemolytic anemia. The predominant forms of B. bacilliformis in this phase are bacilli, 1to 3 µm in length by 0.2 to 0.3 µm in width. Verruga peruana is characterized by wart like growth. As the culture age, cocci, approximately 0.75 µm in diameter appear
B. bacilliformis can adhere to and enter red blood cells and its continued interaction leads to extensive deformation of the red cell surface, as pits and invaginations develop.
Though B. bacilliformis has a restricted geographic habitat and can be effectively controlled by the use of antibiotics and insecticides, it is an interesting organism because it is unique among human pathogens in its parasitic capabilities and in the disease states which it induces.
References:
1. The Prokaryotes- A Handbook on the Biology of Bacteria , Second Edition, Volume 4 , Page no : 3996-4000
2. Yanji Xu and Yan Chai, (2002) Bartonella bacilliformis: Molecular Mechanisms of Invasion, Einstein Quart. J. Biol. Med. (2002) 19:56-58.
3. Krueger, C.M., Marks, K.L. and Ihler, G.M. (1995) Physical Map of the Genome of Bartonella bacilliformis. J. Bact. 177: (24) 7271-7274
4. Webpage of Dr.Garret M. Ihler, Professor, Department of Medical Biochemistry and Genetics ,Texas A&M University, http://www.tamu.edu/genetics/Ihler.htm
Fig 1. Write –Stained Bartonella bacilliformis in blood of an Oroyo fever infected human (Source: The Prokaryotes)
Fig 2 .Bartonella bacilliformis in blood cells prepared for electron microscope examination showing cell wall(pb) , cell membrane(mc) , cytoplasm(c), and nucleoid region(N) (Source : The Prokaryotes)
Fig 3. Bartonella bacilliformis from a culture showing flagella (Source: The Prokaryotes)*Disclaimer - This report was written by a student participaring in a microbiology course at the Missouri University of Science and Technology. The accuracy of the contents of this report is not guaranteed and it is recommended that you seek additional sources of information to verify the contents.
Return to Missouri S&T Microbiology HomePage Go to DJW's HomePage
This Document is maintained by djwesten@ mst.edu
