ORAL COMMUNICATION | Peripheral facial nerve palsy as the first manifestation of multisystem rickettsiosis

Introduction. Rickettsioses are endothelial-tropic infections that may present without pathognomonic signs, causing diagnostic delay. Neurological manifestations, including cranial neuropathies, can represent an early clue to systemic disease even in the absence of eschar. Discussion. A 71-year-old man presented with two weeks of high-grade fever and acute onset of complete peripheral right facial nerve palsy. The absence of vesicles, otalgia, or prodromal symptoms made herpetic infection unlikely. Diffuse maculopapular rash, ankle edema, and markedly elevated C-reactive protein (128.8 mg/L) with preserved organ function suggested acute endothelial dysfunction rather than primary neuropathy. The association of fever, rash, edema, and cranial neuropathy led to early suspicion of rickettsiosis and prompt initiation of doxycycline. Chest CT revealed pleural effusion and bilateral ground-glass opacities. Tests for Mycoplasma pneumoniae, Legionella pneumophila (urinary antigen), EBV, and a multiplex respiratory panel were negative. Rapid clinical improvement followed. The diagnosis was confirmed by positive IgM antibodies against Rickettsia conorii. Conclusions. Peripheral facial nerve palsy may be the first manifestation of multisystem rickettsiosis. Early recognition and serological confirmation allow timely doxycycline therapy and prevent severe systemic involvement.