[Anaplasmosis imitating haematological disease with hyperinflammation]

Area of Science:

• Infectious Diseases
• Microbiology
• Tick-borne Illnesses

Background:

• Anaplasmosis is a significant tick-borne zoonosis caused by Anaplasma phagocytophilum.
• Prompt diagnosis and understanding of its clinical manifestations are crucial for patient management.

Purpose of the Study:

• To report a case of Anaplasmosis in an immunocompetent male presenting with fever, headache, and fatigue post-tick bite.
• To evaluate the utility of next-generation sequencing for diagnosing Anaplasma phagocytophilum infection.

Main Methods:

• Case report of a 73-year-old male with symptoms following a tick bite.
• Utilized 18F-fluordeoxyglucose Positron Emission Tomography (PET) for imaging hyperinflammation.
• Employed amplicon-based 16S/18S rDNA next-generation sequencing (NGS) on ethylenediamine tetraacetic (EDTA) blood for bacterial identification.

Main Results:

• The patient exhibited hyperinflammation and significant spleen and bone marrow uptake on PET scans.
• Anaplasma phagocytophilum was successfully identified using NGS from EDTA blood.
• The patient's symptoms resolved spontaneously without specific antimicrobial therapy.

Conclusions:

• This case highlights the potential of NGS as a diagnostic tool for Anaplasmosis, especially in febrile patients with a history of tick bites.
• Early identification of Anaplasma phagocytophilum via NGS can guide clinical suspicion and management.
• Further research is warranted to establish NGS as a standard diagnostic method for tick-borne diseases.