Chapter 32 -Bartonella spp. by Joseph DeFinis

Bartonella spp.

josephdefinis7 — 2025-10-12 09:02:47 UTC

The genus Bartonella spp. consists of approximately 35 named species. Fourteen species have been associated with human disease, and four have been identified as opportunistic human pathogens. The remaining members have been observed in animal reservoirs such as rodents, ruminants, and moles. Bartonella spp. are most closely related to Brucella abortus and are short, gram-negative, pleomorphic coccobacillary or bacillary, facultative, intracellular bacteria that parasitize mammalian cells. Bartonella spp. are fastidious organisms that are oxidase and catalase negative and grow best on blood-enriched media. More research is required to understand Bartonella spp. pathogenesis it is acknowledged that these organisms display unique pathological methods to stay viable within their host, and the manifestation of illness is dependent on the host's immune system.

Bacillary angiomatosis

josephdefinis7 — 2025-10-12 09:03:20 UTC

Multifocal angioproliferative lesion (e.g., bacillary angiomatosis) in immunocompromised patients. Bacillary angiomatosis (BA) is a vascular proliferative disorder caused by systemic infection with certain species of the bacterium Bartonella. It is characterized by the formation of tumor-like blood vessel growths in the skin and/or internal organs.

Cat Scratch Disease

josephdefinis7 — 2025-10-12 09:03:31 UTC

B. henselae can cause a focal suppurative reaction (e.g., catscratch disease [CSD]) in immunocompetent patients. Cat-scratch disease (CSD), often called cat-scratch fever, is the most common clinical syndrome caused by infection with bacteria of the genus Bartonella, primarily Bartonella henselae (B. henselae). It is a zoonotic infection, meaning it is transmitted from animals (cats) to humans.

Trench Fever

josephdefinis7 — 2025-10-12 09:04:14 UTC

Trench fever, also causes bacillary angiomatosis in immunocompromised patients. Trench fever is caused by the fastidious, gram-negative rod, Bartonella quintana. The species name quintana (meaning "of five") refers to the classic five-day periodicity of the fever episodes. Vector: The disease is transmitted by the human body louse (Pediculus humanus corporis).

Oroya Fever

josephdefinis7 — 2025-10-12 09:04:26 UTC

Infection with B. bacilliformis presents as either an acute

hemolytic bacteremia (Oroya fever) or a chronic vasoproliferative disease. Oroya fever is the acute, severe, and life-threatening phase of an infection caused by the bacterium Bartonella bacilliformis, which is a specific type of bartonellosis. The disease, also known as Carrión's disease, is geographically restricted to the high-altitude Andes Mountains in parts of Peru, Ecuador, and Colombia.

Peliosis Hepatitis

josephdefinis7 — 2025-10-12 09:04:48 UTC

B. henselae also causes rheumatic manifestations and bacillary peliosis hepatitis. Peliosis hepatis (PH) has a well-established and significant connection with disseminated infection by certain species of the Bartonella genus, a condition often referred to as Bacillary Peliosis Hepatis.

This connection represents a severe, systemic manifestation of Bartonellosis, typically observed in immunocompromised individuals.

Carrion

josephdefinis7 — 2025-10-12 09:05:06 UTC

The chronic form of infection is often referred to as Carrion disease, Carrión's Disease (CD) is the official name for the infectious illness caused by the bacterium Bartonella bacilliformis. The disease is a biphasic, vector-borne infection endemic to the high-altitude valleys of the Andes Mountains in South America (Peru, Ecuador, and Colombia).

Verrunga

josephdefinis7 — 2025-10-12 09:05:28 UTC

Carrion disease was named after a medical student named Daniel Carrion, who died after self-inoculation with material from a wartlike lesion (verruga). The connection between "verruga" (specifically Verruga Peruana) and Bartonella is absolute and defines a distinct phase of a specific infectious disease. Verruga peruana is the chronic, eruptive phase of Carrión's disease, which is caused solely by the bacterium Bartonella bacilliformis.

Splenic peliosis

josephdefinis7 — 2025-10-12 09:05:52 UTC

B. henselae also causes rheumatic manifestations like splenic peliosis. Splenic peliosis seldomly occurs, characterized by the presence of multiple, irregular blood-filled cystic cavities within splenic parenchyma. Splenic peliosis, often referred to as Bacillary Peliosis Splenis, is a direct and severe manifestation of disseminated Bartonella infection. It is essentially the splenic equivalent of the more commonly discussed peliosis hepatis.

Erythema nodosum

josephdefinis7 — 2025-10-12 09:06:20 UTC

Erythema nodosum (EN) is a recognized, though uncommon and atypical, cutaneous manifestation associated with infection by bacteria of the genus Bartonella, particularly Bartonella henselae, the causative agent of Cat-Scratch Disease (CSD).