[Bilateral inguinal lymphadenopathy and erythema nodosum: an uncommon presentation of cat scratch disease].

Cat scratch disease is usually revealed by a proximal lymphadenopathy related to the inoculation site. We report a 22-year-old female who presented with erythema nodosum and bilateral inguinal lymphadenopathy. Serologic test and lymph node PCR detection for Bartonella henselae were negative. Nevertheless, the patient received doxycycline and clinical manifestations rapidly resolved. A follow-up detection of IgM and IgG against Bartonella henselae performed 1 month later was positive. This case report illustrates an original presentation of cat scratch disease and reminds us the lack of sensitivity of laboratory investigations.