Negative Lyme Disease Test: 75-Year-Old Man Diagnosed With Neuroborreliosis

Negative Lyme disease tests can occur
Neurologic Lyme disease may be missed early
Further testing led to diagnosis and recovery

Can a patient have Lyme disease despite a negative test? In this Inside Lyme Podcast, I discuss a 75-year-old man whose initial Lyme disease test was negative but who was later diagnosed with Lyme neuroborreliosis and Babesia after additional testing.

Lamichhane and colleagues first discussed this case in the journal Case Reports in Infectious Diseases in 2018.

A 75-year-old Chinese man was evaluated in an emergency room for an unsteady gait. He had a history of hypertension, hyperlipidemia, coronary artery disease, diabetes mellitus, benign prostatic hyperplasia, and osteoarthritis, wrote the authors.

His examination was normal. His blood tests showed mild anemia and a low platelet count. He was sent home.

He was hospitalized four days later with a maximum fever of 105 degrees Fahrenheit and an unsteady gait. He found it difficult to maintain his balance. He suffered from “rigors, chills, diaphoresis, diffuse myalgias, generalized weakness, malaise, confusion, and decreased appetite,” wrote the authors.

Can You Have Lyme Disease With a Negative Test?

This case highlights an important clinical question: can Lyme disease be present despite an initial negative test? Although Lyme disease testing is helpful, no test is perfect. In some cases, physicians may need to pursue additional testing or rely on clinical judgment when symptoms strongly suggest tick-borne illness.

Concerns about Lyme disease test accuracy arise when patients have symptoms consistent with Lyme disease but receive negative screening results. This case illustrates how further evaluation led to a diagnosis despite an initially negative test.

Why This Lyme Disease Test Was Initially Negative

The most significant findings were continued mild anemia, a decrease in his white blood cells, and a marked reduction in his platelet count. The doctors considered Lyme disease. He initially had a negative Lyme disease test. The doctors apparently did not request a Western blot test after the initial negative Lyme disease test.

The doctors suspected a bacterial infection. They prescribed ceftriaxone, ampicillin, and vancomycin.

By the next day, the man’s condition worsened. His heart rate climbed to over 200. His blood pressure dropped. He developed encephalopathy. Encephalopathy refers to brain disease, damage, or malfunction. Symptoms can range from memory loss or subtle personality changes to acute confusion and dementia.

His doctors then ordered more than the screening Lyme disease test. His blood tests were now positive for Lyme disease and Babesia. He was positive for Lyme disease by a Lyme IgG and IgM ELISA test and Lyme IgM Western blot. He was also positive by Babesia microti IgG and IgM antibody tests.

The patient ultimately tested positive for Lyme disease and Babesia. Co-infections such as Babesia can complicate diagnosis and contribute to more severe illness, particularly in older adults.

Lyme Neuroborreliosis Without Signs of Meningitis

His doctors arranged for a spinal tap despite the absence of evidence of meningitis. His spinal tap was positive for Lyme disease by IgM and IgG Western blot bands. Three of 3 IgM Western blot bands were positive. Nine of 10 IgG Western blot bands were positive for Lyme disease. Doctors only need 2 of 3 IgM and 5 of 10 IgG bands to meet CDC surveillance criteria.

Spinal taps have not been all that helpful in some studies. Less than one in ten patients with chronic neurologic Lyme disease tested had an abnormal spinal tap in a 1990 study by Logigian and colleagues.

The man was diagnosed with Lyme neuroborreliosis. He was prescribed doxycycline for 21 days.

Although spinal fluid testing is not always diagnostic, the findings in this case strongly supported Lyme neuroborreliosis. Learn more about neurologic Lyme disease and how it can affect the brain, nerves, cognition, and balance.

He was not treated for Babesia. He would have had to have been treated with medication like the combination of atovaquone and azithromycin.

Within 48 hours, his cognitive function and gait returned to normal, according to the authors.

The authors summarized the difficulties making a diagnosis of Lyme neuroborreliosis. They write, “Here we have presented a patient who had no characteristic clinical signs of LD, whose main symptoms were a high fever, encephalopathy, diffuse myalgia, and tachycardia.” A broad range of other tests were normal.

“The single diagnostic modality yielding concrete results was the patient’s CSF Lyme serology,” wrote the authors.

What This Case Teaches About Lyme Disease Test Accuracy

This case highlights several important lessons:

1. Lyme disease can lead to an abnormal gait and encephalopathy.
2. Doctors may diagnose Lyme disease despite an initial negative Lyme disease test.
3. Neurologic Lyme disease can occur despite the absence of signs of meningitis.

Questions Raised by This Case

1. How often have doctors dismissed Lyme disease when screening tests are negative?
2. Should the doctors have treated for Babesia? He was over 50 years old, placing him at higher risk of Babesia complications. Follow-up would have helped assess symptoms and recovery.
3. What was the long-term outcome for this patient with Lyme disease and Babesia?

Clinical Perspective

This case illustrates why Lyme disease should not always be excluded solely because an initial screening test is negative. The patient’s neurologic symptoms, gait disturbance, fever, thrombocytopenia, and eventual positive Lyme and Babesia testing supported a tick-borne illness despite an early negative result.

For clinicians, the case serves as a reminder that Lyme disease diagnosis involves both laboratory testing and clinical judgment, particularly when evaluating patients with possible neurologic Lyme disease.

Frequently Asked Questions

Can you have Lyme disease with a negative test?

Yes. Lyme disease may occasionally be missed by initial testing. Additional testing and clinical evaluation may be necessary when symptoms strongly suggest Lyme disease.

What is Lyme neuroborreliosis?

Lyme neuroborreliosis occurs when Lyme disease affects the nervous system. Symptoms may include cognitive changes, balance problems, neuropathy, meningitis, or encephalopathy.

Can Lyme disease cause encephalopathy?

Yes. Some patients with neurologic Lyme disease develop encephalopathy, which may cause confusion, cognitive impairment, memory problems, or gait disturbances.

Can Babesia occur with Lyme disease?

Yes. Babesia and Lyme disease are both transmitted by Ixodes ticks and may occur together, potentially increasing illness severity.

Clinical Takeaway

A negative Lyme disease test does not always exclude Lyme disease. In this case, a 75-year-old man with fever, encephalopathy, gait instability, and abnormal blood counts was ultimately diagnosed with Lyme neuroborreliosis and Babesia despite an initially negative screening test.

This case highlights the importance of considering Lyme disease when symptoms and clinical findings remain suspicious, even when early testing is negative.

Related Articles

Why Lyme disease tests miss infections
Neurologic Lyme disease: symptoms and diagnosis
Babesia remains a clinical diagnosis for some patients
Why Lyme tests medicine remains challenging

---

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