New Borrelia Species Complicate Lyme Disease Diagnosis

Researchers identified new Borrelia species associated with Lyme-like illness.
Some patients presented with neurologic symptoms, rash, or severe systemic illness.
The findings highlight ongoing challenges in Lyme disease diagnosis and testing.

Lyme disease is caused by Borrelia bacteria, but researchers continue to identify additional Borrelia species associated with Lyme-like illness.

A discovery by researchers at Mayo Clinic demonstrates the complexity of tick-borne organisms. Pathologists at the institution described a new Borrelia burgdorferi sensu lato genospecies in six patients. [1]

The new species, provisionally named Borrelia mayonii, was identified in the Upper Midwest, although researchers suggested it may exist elsewhere. Symptoms were similar to those seen with Borrelia burgdorferi, the primary bacterium associated with Lyme disease. [1]

Patients Presented With Lyme-Like Symptoms

“Five of the six patients with atypical PCR [polymerase chain reaction] results had presented with fever, four had diffuse or focal rash, three had symptoms suggestive of neurological inclusion, and two were admitted to the hospital. The sixth patient presented with knee pain and swelling.” [1]

All six patients were diagnosed using PCR testing. [1]

Researchers Also Identified Borrelia Bissettii-Like Spirochetes

Meanwhile, researchers successfully cultivated Borrelia burgdorferi and Borrelia bissettii-like spirochetes from 24 individuals in the Southern United States. [2]

Rudenko and colleagues described patients from Georgia and Florida with symptoms including “severe headache, nausea, muscle and joint pain, numbness and tingling sensations in extremities, neck pain, back pain, panic attacks, depression, dizziness, vision problems, sleep problems, and shortness of breath.” [2]

The investigators used a modified Kelly-Pettenkofer medium rather than Barbour-Stoenner-Kelly-H (BSK-H) medium to culture the specimens. Positive cultures were further characterized using DNA purification, PCR amplification, sequencing, sequence analysis, multilocus sequence analysis (MLSA), and transmission electron microscopy. [2]

Borrelia Miyamotoi Adds Additional Complexity

Borrelia miyamotoi, a relapsing fever spirochete capable of causing symptoms similar to Lyme disease, has also been identified in patients through blood smears, cerebrospinal fluid testing, PCR analysis, and molecular detection in whole blood samples. [3-6]

Cases of meningoencephalitis caused by Borrelia miyamotoi have also been reported in immunocompromised patients. [4,5]

Current Lyme Disease Tests Have Limitations

The investigators did not address the availability of these tests. The laboratory-developed assays described in the studies were not FDA-approved.

In Scientific American, infectious disease physician and researcher John Aucott cautioned about test availability. “These tests require physicians to send samples to the Mayo Clinic … that just may not happen.” [7]

Nor did the investigators address the reliability limitations of current Lyme disease tests.

Molins from the Centers for Disease Control and Prevention, Division of Vector-Borne Diseases, found that “existing two-tier serology-based assays yield low sensitivities (29–40%) for early infection.” [8]

Clinical Perspective

The discovery of additional Borrelia species highlights the growing complexity of tick-borne disease diagnosis.

Some newer or less-recognized Borrelia species may present with symptoms similar to Lyme disease and may complicate diagnostic evaluation.

Without reliable commercial testing, some patients with Lyme-like illness may be at risk of delayed diagnosis or misdiagnosis unless clinicians apply careful clinical judgment.

Frequently Asked Questions

What is Borrelia mayonii?

Borrelia mayonii is a Borrelia species identified by Mayo Clinic researchers that can cause Lyme-like illness. [1]

What is Borrelia miyamotoi?

Borrelia miyamotoi is a relapsing fever spirochete transmitted by ticks that may cause fever, neurologic symptoms, and Lyme-like illness. [3-6]

Can standard Lyme disease tests miss newer Borrelia species?

Possibly. Researchers have raised concerns regarding the sensitivity and availability of current Lyme disease testing methods. [7,8]

To learn more about Borrelia bissettii, read “Culture evidence of Lyme disease in antibiotic treated patients living in the Southeast.”

To learn more about Borrelia miyamotoi, read “Where is the FDA test for relapsing fever spirochete, Borrelia miyamotoi?” and “Larval ticks may be a threat after all: insights based on study of Borrelia miyamotoi.”

---

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