Severe Anaplasmosis Symptoms: Confusion After a Tick Bite
Fever after a tick bite is common.
Confusion is not.
It may signal severe infection.
Severe anaplasmosis symptoms can develop quickly—and may be missed if early signs are subtle.
Confusion after a tick bite is a warning sign that requires urgent evaluation.
Many patients expect a rash—but anaplasmosis symptoms often occur without one.
Early symptoms can resemble a viral illness—making diagnosis easy to miss.
Start here: Lyme disease symptoms guide
Confusion After a Tick Bite
In a case report by Aydin and colleagues, a 66-year-old woman from Connecticut was admitted to the emergency department with confusion and lethargy.
She had experienced fever, chills, generalized weakness, and poor appetite for two days.
Her medical history included rheumatoid arthritis and hypothyroidism.
The patient enjoyed gardening and reported several tick bites in her left armpit three days before presentation.
She did not have a rash—a detail that can delay recognition of anaplasmosis symptoms.
As her mental status worsened, her husband contacted emergency services.
Laboratory Findings and Diagnosis
Laboratory testing revealed:
- Pancytopenia
- Hyponatremia
- Elevated liver enzymes
- Mild hyperbilirubinemia
- Lactic acidosis
These findings suggested a systemic infection affecting multiple organ systems.
PCR testing supported the diagnosis of severe anaplasmosis.
When Anaplasmosis Becomes Severe
The patient was treated promptly with doxycycline.
Despite early treatment, her condition worsened.
She developed acute hypoxic respiratory failure due to acute respiratory distress syndrome (ARDS).
High-flow nasal cannula (HFNC) therapy was required to maintain oxygenation.
Severe complications like these are uncommon—but important to recognize early.
Risk Factors for Severe Disease
The patient was taking immunosuppressive medications for rheumatoid arthritis.
This likely contributed to the severity of her illness and the involvement of multiple organ systems.
Severe cases are more likely in older adults and those on immunosuppressive therapy.
Patients with weakened immune systems may be at higher risk for rapid disease progression.
Why Early Recognition Matters
Prompt diagnosis and treatment are essential to prevent complications such as respiratory failure, kidney injury, bleeding disorders, and—in rare cases—death.
Doxycycline remains the first-line treatment and can be life-saving when started early.
Anaplasmosis symptoms without a rash can delay diagnosis.
This case highlights the importance of maintaining a high index of suspicion in patients with recent tick exposure and unexplained systemic symptoms.
Clinical Takeaway
Severe anaplasmosis can present with confusion, systemic symptoms, and rapid progression to respiratory failure.
If symptoms escalate quickly—especially with confusion or weakness—early evaluation and treatment are critical.
Related Articles
- Can anaplasmosis cause heart problems?
- Anaplasmosis in the brain
- Anaplasmosis and cognitive impairment
References
- Aydin Y, Vemuri B, Ahmed SM, Elgamal M, Bilgin S. Severe Anaplasmosis With Multiorgan Involvement in a Rheumatoid Arthritis Patient. Cureus. 2023.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
