Cat Scratch Disease

Question 1

Causative organism

Answer 1

Causative agent: Bartonella henselae
Vector: Ctenocephalides felis (Cat fleas)

Question 2

Clinical Picture:

Answer 2

• At site of inoculation : Papule or pustule or Vesicle
• Regional Lymphadenopathy
• Fever
• Splenomegaly
• Hepatomegaly
• Optic neuritis
• Arthralgia
• Arthritis
• Erythema nodosum
• Thrombocytopenic purpura
• Pneumonia
• Osteomyelitis
• Encephalitis (rare)
  *If pt is HIV : Bacillary angiomatosis, Hepatic peliosis
  (angioproliferation look like kaposi sarcoma) vessels
  Hepatic peliosis: blood-filled cystic spaces in the liver

Question 3

Diagnosis

Answer 3

Diagnosis:(3/4)
* Hx of Cat scratch or licking of open skin
* -ve tests for other LNS causes
* L.N. Biopsy
* +ve serology for (Cat Ag tests)
Acute infection if: IgM >1/160
IgG >1/256
Chronic infection if: IgG >1/800

Question 4

Treatment

Answer 4

Self limited disease
*Abs not recommended in healthy people with mild to moderate symptoms.
*Used in severe disease
Azithromycin 500mg 1st day then 250mg for next 4 days
*Alternatives: Cipro, doxy
*In HIV pts if Bacillary angiomatosis or hepatic peliosis occured Treatment for 4w is required