Bartonellosis

Synonyms and Key Words: Carrion's disease or Oroya fever

Bartonellosis a rare infectious disease found only in certain regions of the Andes mountains of South America. Endemic in some areas of Peru, bartonellosis is caused by infection with the bacterium Bartonella bacilliformis and transmitted by sandflies of genus Lutzomyia. Bartonellosis has been recently found in the United States as well as in Canada.

Pathophysiology
Bartonellosis is usually characterized by an acute stage with primarily vascular effects and a chronic stage associated with skin symptoms. In the acute stage (also known as Oroya fever or Fiebre de la Oroya), bartonellosis is a sudden, potentially life-threatening illness associated with high fever and decreased levels of circulating red blood cells (i.e., hemolytic anemia). The acute phase typically lasts two-to-four weeks. Peripheral blood smears shows anisomacrocytosis with many bacilli adherent to red blood cells. Thrombocytopenia is also seen and can be very severe. Neurologic involvement is sometimes seen (neurobartonellosis) and the prognosis in this case is very guarded. It can present as spinal meningitis or as paralysis. In the acute stage, the most feared complication is fulminant Salmonella superinfection: for this reason chloramphenicol is the preferred antibiotic treatment.

The chronic manifestation—Verruga Peruana—consists of a benign skin eruption with raised, reddish-purple nodules (angiomatous tumours). Visualization is possible using a silver stain (the Warthin–Starry method).

Untreated, bartonellosis has a death rate of about 40%.

History
The disease was named after Dr. Alcides Carrión of Cerro de Pasco, Peru. Carrión described the disease after being infected on his request by Doctor Evaristo M. Chávez, a close friend and coworker in Dos de Mayo National Hospital. Carrión kept a meticulous clinical history until he was not able to do so because of the high fever. Carrión proved that "Fiebre de la Oroya" and "Verruga Peruana" were two stages of the same disease, not two different ones as thought at the time.

Dr Carrion had infected himself from the pus in the purple lesion in a bart No. 1 subspecies (bartonellosis) patient in 1885. He died from the disease several weeks later. Bart "1" is considered the most deadly bart to date..rarely killing in late chronic stage but in early stage some studies show a death rate of up to 90%. He was able to show the 2 disease stages where in fact 1 sole disease. He gave his life for us, and it led to the discovery of many more (23 subspecies to date) of bartonella. Although his work didn't save anyone at that time, he surely got the ball rolling. On his honor, we shall be forever grateful for his efforts on this disease.

The causative bacterial agent of bartonellosis was discovered by Alberto Barton in 1905, but it was not published until 1909. Barton originally identified them as endoglobular structures, which actually were the bacteria living inside red blood cells. Until 1993, the Bartonella genus contained only one species; there are now 23 identified species, all of them within family Bartonellaceae.