[Preauricular lymphadenopathy related to Bartonella henselae]

Introduction: Cat scratch disease is characterized by adenitis with usually positive outcome. We reported two cases of cat scratch disease with preauricular involvement occurring in immunocompetent patients.

Observations: Observation 1: a 28-year-old man had a recent onset of left cervical swelling, with a peripheral facial paralysis and liver cytolysis. Serologies for EBV, viral hepatitis, CMV, HIV and toxoplasma were negative. Node excision biopsy suggested granulomatous lymphadenitis and Bartonella henselae PCR on lymph node was positive. With doxycyclin for 3 months, associated with rifampicin for 15 days, abnormal liver function disappeared and facial paralysis improved. Observation 2: a 17-year-old man had parotid swelling associated with right posterior cervical lymphadenopathies associated with fever and profuse sweating. A large right preauricular lymphadenopathy with necrotic remodeling was visible on the CT-scan. Lymph fluid B. henselae PCR was positive. Positive outcome occurs after surgical drainage and short azithromycin treatment.

Conclusion: Physicians should be aware of the rare preauricular localization of cat scratch disease and ask for contact with a cat. Parotid tumor localization, lymphoma or tuberculosis should be ruled out. Diagnosis is based on the B. henselae PCR. Outcome is often spontaneously positive but surgical treatment may be required.