Introduction: Anaplasma phagocytophilum, a tick-borne bacterium causing human granulocytic anaplasmosis (HGA), is emerging in North America and Europe. It typically presents as a nonspecific febrile illness; neurologic complications are rare. Guillain-Barré syndrome (GBS), particularly the acute inflammatory demyelinating polyneuropathy (AIDP) variant, is an immune-mediated condition often post-infectious. We describe a rare case of Anaplasma-associated AIDP with respiratory failure in an elderly woman, despite unclear tick exposure. Description: An 82-year-old woman with hypertension and AV block (s/p pacemaker) presented with bilateral leg weakness, fatigue, anorexia, and malaise. She lived rurally with frequent outdoor exposure. She denied known tick bites but had a painless erythematous abdominal rash for one week. On arrival, she was febrile, leukopenic, and thrombocytopenic. She developed ascending weakness, areflexia, and acute hypoxemic respiratory failure requiring intubation. CT chest showed pulmonary edema and atelectasis. CSF revealed albuminocytologic dissociation (protein 94, WBC 12). Peripheral smear and other infectious workup were negative; however, Anaplasma PCR was positive. She was treated with doxycycline and ceftriaxone. AIDP was diagnosed clinically and supported by CSF findings. Liberation from mechanical ventilation was delayed due to neuromuscular weakness. She improved following five sessions of plasmapheresis, was extubated, and discharged with near-complete recovery. Discussion: This case illustrates an atypical presentation of anaplasmosis causing polyneuropathy and respiratory failure. Most HGA cases present with nonspecific febrile symptoms; neurologic involvement is rare. To our knowledge, this is the first reported case of Anaplasma phagocytophilum triggering AIDP with ICU-level respiratory compromise. Classic AIDP features included albuminocytologic dissociation and rapid response to plasmapheresis. Respiratory failure occurs in up to 25% of GBS cases, with mortality near 5%. As tick-borne illnesses expand geographically, clinicians should consider Anaplasma in acute flaccid paralysis—even without a known bite. Early recognition and dual therapy can improve outcomes.
Aiti et al. (Sun,) studied this question.