Bartonella bacilliformis

Question 1

B bacilliformis - organism

Answer 1

Flagellated, gram negative, facultative intracellular aerobic
2-3um

Question 2

B bacilliformis - distribution

Answer 2

Andean region - mostly Peru
500-2300m above sea level

Question 3

B bacilliformis - transmission

Answer 3

Not clear
Role of vector transmission through sand flies - L verrucarum, L peruensis

Question 4

B bacilliformis - pathogenesis

Answer 4

B bacilliformis infects erythroyctes and endothelial cells
-Physical damage and introduction of antigens into erythrocyte membrane producing intense erythrophagocytosis
-Resulting in haemolytic anaemia

Virulence factors [adhesin, flagellin, hemin] - evade host immune response

Acute phase - increased IL-10 secretion by RBCs, decrease cytokine production suppresses T helper cells, macrophrages and dendritic cells

Question 5

B bacilliformis - acute phase

Answer 5

Fever and haemolytic anaemia [acute bacteraemia for 60 days]

Complications common - superinfections, haematological, cardiovascular

Question 6

B bacilliformis - chronic phase

Answer 6

Occur weeks to months after acute illness

Eruption of lesions - containing serosanguinous fluid

Miliary = multiple red papules <3mm
Mular = blood-filled nodules
Diffuse = group of subdermal nodules >5mm

Question 7

B bacilliformis - diagnosis

Answer 7

Acute phase:
-Blood smears
-Culture
-PCR
-Immunological tests - IFA, immunoblot-based protocol

Chronic phase:
-Clinical diagnosis with or without skin biopsy
-Culture

Question 8

B bacilliformis - treatment

Answer 8

Acute phase:
-Ciprofloxacin
-Chloramphenicol
-Ceftriaxone
-Co-amoxiclav

Chronic:
-Azithromycin
-Ciprofloxacin
-Rifampicin