Question
Which among the following is an organism causing skin condition as seen after a scratch from a pet cat as represented in the photograph below ?

A. Bartonella bacilliformis.
B. Bartonella henselae.
C. Bartonella qunitana.
D. Ehrlichia.
Show Answer
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Correct Answer » B Explanation |
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Ans: B. Bartonella henselae.
The skin condition seen above represents Cat scratch disease (CSD).
Catscratch disease (CSD)
- Also known as catscratch fever or subacute regional lymphadenitis, is a bacterial infection caused by Bartonella henselae, a gram-negative rod.
- Transmission can occur by petting alone with subsequent self-inoculation via a mucous membrane, skin break, or conjunctiva. However, infection with B henselae can be transmitted by arthropod vectors, and a history of an animal scratch or bite is not necessary for disease transmission.
Presentation:
- Red-brown nontender papules at the site of inoculation 3-10 days after the bacteria are introduced
- Tender regional lymphadenopathy.
- Systemic symptoms like Malaise/fatigue,Fever,Anorexia,Headache,Sore throat,Arthralgia .
- CNS findings are present in 5% of patients .
- Indirect fluorescence assay (IFA) testing and Enzyme-linked immunoassay (ELISA) are used to detect serum antibody to B henselae.
- Histopathological features of lymph nodes are consistent but not pathognomonic for CSD. Features include granuloma formation, stellate abscesses, and lymphocytic infiltrates. Brown-Hopp tissue Gram stain and Warthin-Starry silver staining can show clumps of small, curved, gram-negative bacilli.
- People who have a healthy immune system should recover fully without treatment. In people with a weakened immune system, treatment with antibiotics such as azithromycin can be helpful. Other antibiotics may be used, including clarithromycin, rifampin, trimethoprim-sulfamethoxazole, or ciprofloxacin.



