Dual detection of Neoehrlichia mikurensis and Anaplasma phagocytophilum: How biplex PCR led in France to the diagnosis of neoehrlichiosis in post-tick bite fever

Objectives

Neoehrlichia mikurensis (NM) is an emerging intracellular bacterium member of the Anaplasmatacecae family. So far, only four cases have been described in France, all of them retrospectively.

Methods

This study describes two new cases of NM discovered following implementation of a biplex PCR targeting both Anaplasma and NM.

Results

Two immunocompetent patients developed a flu-like illness within 14 days after an identified tick bite. Both had negative Anaplasma PCR, but by using this biplex PCR NM, infection was diagnosed in both cases. One patient recovered spontaneously while the second was successfully treated by a seven-day course of doxycycline.

Conclusion

Present in Eastern France, NM is underdiagnosed. Biplex PCR screening of NM with A. phagocytophilum could effectively address this issue.