Cellulitis of the face associated with SENLAT caused by Rickettsia slovaca detected by qPCR on scalp eschar swab sample: An unusual case report and review of literature

Abstract

Background: Tick-borne rickettsioses are infectious diseases caused by obligate intracellular Gram-negative bacteria belonging to the spotted fever groupof Rickettsia.

Methods: We describe an unusual case of SENLAT (Scalp eschar and neck lymphadenopathy after tick bite), caused byRickettsia slovaca, associated with a cellulitis of the face in a 70-year-old woman, and diagnosed using qPCR on a scalp eschar swab. We review the literature regarding cases of SENLAT-associated-cellulitis and case of SENLAT diagnosed by qPCR on scalp eschar swabs.

Results: We found only one previous report of SENLAT associated with a cellulitis of the face. It was a nine-year-old French girl diagnosed by seroconversion for Rickettsia sp. Our review of the literature showed that qPCR on eschar swab samples is a less invasive method than performing cutaneous biopsy of the eschar and has good sensitivity and specificity (90% and 100%, respectively).

Conclusions: We report the second case of cellulitis of the face associated with the SENLAT syndrome. Detection of Rickettsia by qPCR on swab sample of the scalp eschar is a simple, noninvasive technique allowing rapid diagnosis and treatment when SENLAT is suspected.

Keywords: Periorbital cellulitis; R. slovaca; SENLAT syndrome.