Episode 624: FDA-Cleared Lyme Disease Testing: What's New at IGeneX? – Dr. Jyotsna Shah | LIVE from ILADS

3 hours ago

Could a major breakthrough in Lyme disease testing help more patients get answers sooner? What does FDA clearance mean for people who have struggled with negative Lyme tests despite ongoing symptoms?

In this LIVE from ILADS interview, Tick Boot Camp co-host Rich reunites with Dr. Jyotsna Shah, PhD, President and Laboratory Director of IGeneX, to discuss an important development in Lyme disease diagnostics: FDA clearance of the iDart Lyme IgM and IgG ImmunoBlot test kits.

Recorded at the 2025 International Lyme and Associated Diseases Society (ILADS) Conference in San Antonio, Texas, the conversation explores how expanded Borrelia antigen coverage, updated antibody interpretation criteria, and single-step immunoblot testing could improve access to Lyme disease diagnostics.

Dr. Shah also discusses the importance of testing for additional tick-borne infections, including Babesia, Bartonella, Anaplasma, Ehrlichia, and Rickettsia.

The interview addresses several questions that matter to the Lyme disease community:

What does FDA clearance mean for IGeneX Lyme disease testing?
Why are Lyme Western blot bands 31 and 34 important?
How do IGeneX ImmunoBlot tests differ from conventional two-tier Lyme testing?
What is the difference between Lyme Borrelia and tick-borne relapsing fever Borrelia?
Why might someone with Lyme-like symptoms test negative for Lyme disease?
Are Babesia and other tick-borne infections becoming more common?
Will FDA clearance make specialized Lyme testing easier to obtain through insurance?

The biggest takeaway: Dr. Shah believes broader diagnostic tools and improved access to testing could help more patients receive timely answers and appropriate medical care.

Meet Dr. Jyotsna Shah, PhD

Dr. Jyotsna S. Shah, PhD, is President and Laboratory Director of IGeneX, a specialty laboratory based in Milpitas, California, focused on diagnostic testing for Lyme disease and other tick-borne infections.

She has spent decades working to advance laboratory methods for detecting infectious diseases, including Borrelia and Babesia.

Dr. Shah has also been involved in developing and evaluating immunoblot testing, fluorescence in situ hybridization (FISH), and other laboratory techniques.

Her work includes efforts to improve the detection of tick-borne pathogens that may not be identified through commonly used testing approaches.

During this interview, she shares updates on IGeneX's diagnostic technology, FDA clearance, and efforts to expand testing availability.

Learn more about the laboratory at the official IGeneX website.

FDA Clearance for Lyme IgM and IgG ImmunoBlot Tests

The biggest announcement in this interview is the FDA clearance of two Lyme disease immunoblot test kits.

The iDart Lyme IgG ImmunoBlot Kit received FDA clearance in 2024.

The iDart Lyme IgM ImmunoBlot Kit received FDA clearance in 2025.

Both kits are manufactured by ID-FISH Technology, Inc., which has a licensing relationship with IGeneX.

The tests use recombinant antigens from multiple Borrelia species and strains to detect antibodies associated with Lyme disease.

Dr. Shah explains that the FDA clearance process included evaluation of the tests' antigen coverage and interpretation criteria.

She views the clearances as an important milestone for Lyme disease diagnostics.

Importantly, the clearances apply to the specific iDart immunoblot kits, not every test offered by IGeneX.

Read the official announcement about FDA clearance of the Lyme IgM and IgG ImmunoBlots.

What Is a Lyme Disease ImmunoBlot?

An immunoblot is a laboratory test that detects antibodies directed against specific proteins, called antigens.

When someone is exposed to Borrelia bacteria, their immune system may produce antibodies against different bacterial proteins.

An immunoblot measures antibody reactivity to selected antigens.

Dr. Shah discusses two major antibody classes:

IgM antibodies: Often appear earlier during an immune response.

IgG antibodies: Generally develop later and may remain detectable long after an infection.

Both can provide useful information when interpreted in the context of symptoms, exposure history, and other clinical findings.

However, antibody results alone cannot reliably determine whether an infection is currently active, and IgM results can be misleading when used to evaluate symptoms of long duration.

Why Lyme Disease Testing Bands 31 and 34 Matter

One of the most important developments discussed is the inclusion of bands 31 and 34 in the FDA-cleared immunoblot kits.

These bands correspond to Borrelia outer surface proteins:

Band 31: Outer surface protein A, or OspA
Band 34: Outer surface protein B, or OspB

Dr. Shah explains that IGeneX has long considered these bands important when evaluating Lyme disease antibody responses.

She emphasizes that the FDA-cleared tests include these antigens in their interpretation criteria.

The kits use antigen-group interpretation rules rather than simply adopting conventional CDC-associated Western blot band counts.

This is significant because different diagnostic methods may recognize different antibody patterns.

However, no individual band establishes a Lyme disease diagnosis by itself.

Positive antibody findings must be interpreted alongside clinical information, and some bands can have limitations involving cross-reactivity or prior vaccination.

Learn more about the IGeneX FDA-cleared immunoblot technology.

Single-Step Lyme Testing vs. Traditional Two-Tier Testing

Rich asks Dr. Shah to explain how the new immunoblot approach differs from conventional Lyme disease testing.

Traditional standard two-tier testing generally involves two sequential steps.

The first test screens for antibodies.

If the screening result meets the laboratory's criteria, a second test is performed.

Depending on the testing algorithm, that second test may be an immunoblot or another antibody assay.

Dr. Shah explains that the FDA-cleared iDart ImmunoBlot kits are designed to function as stand-alone antibody tests within their authorized intended use.

This means a laboratory does not necessarily need to follow the same two-step workflow when using these particular kits.

She believes this could simplify testing and make broader diagnostic technology available to additional laboratories.

Single-step testing does not eliminate the possibility of false-negative or false-positive results, and test selection should remain guided by clinical circumstances.

Why IGeneX Uses Antigens From Multiple Borrelia Species

Dr. Shah emphasizes the importance of recognizing diversity among Borrelia bacteria.

Lyme disease is associated with multiple Borrelia species, including species found in North America and Europe.

Different species and strains may vary in their antigenic characteristics.

Dr. Shah explains that IGeneX incorporates antigens from multiple species and strains to broaden antibody recognition.

She describes the laboratory's approach as particularly relevant for patients with potential exposure in different geographic regions.

The conversation also distinguishes Lyme disease Borrelia from tick-borne relapsing fever Borrelia.

These are related groups of bacteria, but they are associated with distinct infections and require appropriate diagnostic interpretation.

Lyme Borrelia vs. Tick-Borne Relapsing Fever Borrelia

During the interview, Dr. Shah describes IGeneX testing for two different groups of Borrelia.

Lyme disease Borrelia: She discusses testing that incorporates antigens representing nine Borrelia species associated with Lyme disease.

Tick-borne relapsing fever Borrelia: She describes a separate testing approach involving eight species.

Together, these represent 17 species considered across the two testing categories discussed in the interview.

Dr. Shah emphasizes that patients with similar symptoms may have different infections.

She also explains that some people with tick-borne relapsing fever Borrelia may not describe the classic recurring fever pattern traditionally associated with the disease.

An important distinction is that the FDA-cleared Lyme ImmunoBlot kits should not be described as one FDA-cleared test that detects all 17 species.

The interview discusses separate Lyme disease and relapsing fever testing categories.

Could Tick-Borne Relapsing Fever Be Missed in Patients With Lyme-Like Symptoms?

Dr. Shah describes her laboratory's experience evaluating patients who have symptoms suggestive of tick-borne illness but negative Lyme disease testing.

She explains that some have shown evidence of exposure to relapsing fever Borrelia.

The conversation also touches on laboratory findings involving selected patients reporting Morgellons symptoms.

Dr. Shah describes identifying relapsing fever Borrelia-related findings in some of these patients.

These observations are part of her laboratory experience and do not establish that relapsing fever Borrelia causes Morgellons or explains persistent symptoms in all patients.

They do, however, highlight why clinicians may consider alternative diagnoses when evaluating unexplained symptoms and relevant exposure histories.

Why Lyme Disease Testing Should Consider Co-Infections

Rich and Dr. Shah discuss the growing recognition of infections that can occur alongside Lyme disease.

A tick may carry more than one pathogen, and people may also experience multiple exposures over time.

Dr. Shah explains that patients with suspected tick-borne illness may need evaluation for additional pathogens depending on their symptoms and risk factors.

She discusses several groups of organisms:

Borrelia: Bacteria associated with Lyme disease and relapsing fever.
Babesia: Parasites that infect red blood cells and cause babesiosis.
Bartonella: Bacteria associated with several human diseases, although the role of ticks in transmitting human Bartonella infection remains unproven.
Anaplasma: Bacteria responsible for anaplasmosis.
Ehrlichia: Bacteria responsible for ehrlichiosis.
Rickettsia: Bacteria associated with several tick-borne illnesses, including spotted fever group infections.

Dr. Shah believes broader testing panels can help identify infections that might otherwise be overlooked.

However, comprehensive panels are not automatically necessary for every patient.

Testing decisions should reflect symptoms, geographic exposure, clinical findings, and the performance characteristics of each assay.

Is Babesia Becoming More Common?

One of the most interesting discussions concerns Babesia, a parasite that infects red blood cells.

Rich shares observations from Tick Boot Camp interviews suggesting that Babesia is being discussed more frequently among patients with complex tick-borne illnesses.

Dr. Shah agrees that Babesia has become increasingly important in laboratory testing.

She references data from the IGeneX patient population in which Babesia findings were particularly common.

These laboratory observations do not necessarily represent prevalence in the general population.

Rich asks whether the apparent increase reflects more infections or improved testing.

Dr. Shah believes both may contribute, but emphasizes that improved diagnostic methods have helped identify infections that were previously overlooked.

Dr. Shah's Role in Babesia Testing in New York

Dr. Shah shares a story about her work with Dr. Richard Horowitz around 1999.

She recalls helping bring greater attention to Babesia in New York through laboratory testing.

At that time, she was working with Babesia FISH testing, a technique designed to identify genetic material within organisms in patient samples.

She describes discussing Babesia findings with researchers familiar with the parasite.

Her experience illustrates how diagnostic methods and scientific collaboration can contribute to increased recognition of tick-borne diseases.

Dr. Shah believes that improved testing remains an important factor in identifying Babesia infections.

For additional perspectives on Lyme disease and co-infections, explore Tick Boot Camp's featured profile of Dr. Richard Horowitz.

What Animals Carry Babesia?

Rich asks Dr. Shah about the relationship between Babesia and wildlife populations.

The conversation includes deer, horses, sheep, dogs, cats, and other animals.

Dr. Shah explains that Babesia organisms occur in multiple animal species.

However, different Babesia species have different host relationships.

For human babesiosis caused by Babesia microti in the northeastern United States, white-footed mice and certain other small mammals are important reservoir hosts.

Deer play an important role in supporting blacklegged tick populations, but they are not considered the primary reservoir for B. microti.

This distinction matters when discussing how babesiosis is maintained and transmitted in the environment.

Why FDA Clearance Could Improve Access to Lyme Testing

Near the end of the interview, Rich asks whether FDA clearance could make IGeneX testing more accessible through health insurance.

Dr. Shah explains that obtaining clearance was an important step toward expanding availability.

She discusses efforts to secure billing codes and work with Medicare and other insurers.

At the time of recording, these efforts were ongoing.

Dr. Shah hopes the technology will eventually become available through more local laboratories rather than requiring patients to rely exclusively on specialized testing facilities.

This could potentially reduce barriers involving geography, laboratory access, and insurance reimbursement.

However, FDA clearance does not automatically guarantee insurance coverage.

Coverage depends on factors including the insurer, medical necessity policies, billing codes, laboratory participation, and the specific test ordered.

The Importance of Early and Accurate Diagnosis

Dr. Shah repeatedly emphasizes the importance of identifying Lyme disease and other tick-borne infections as early as possible.

Earlier diagnosis can help patients receive appropriate treatment and reduce the risk of certain complications.

She believes diagnostic tools that recognize a broader range of antibody responses may contribute to that goal.

At the same time, no Lyme antibody test can detect every infection, particularly in the earliest stages before antibodies have developed.

Patients with a clinically characteristic erythema migrans rash may be diagnosed and treated without waiting for laboratory confirmation.

Testing is one part of a broader medical evaluation.

Key Takeaways

IGeneX-associated Lyme ImmunoBlot technology achieved FDA clearance. The iDart Lyme IgG kit was cleared in 2024 and the IgM kit in 2025.
Bands 31 and 34 are included. These represent OspA and OspB antigens used in the tests' interpretation.
The kits use antigens from multiple Borrelia species and strains. This is intended to broaden antibody detection.
The FDA-cleared kits are designed as stand-alone immunoblot tests. They differ from traditional two-tier testing workflows.
Lyme disease and tick-borne relapsing fever are distinct infections. Dr. Shah discusses separate testing approaches for these Borrelia groups.
Babesia remains an important diagnostic consideration. Dr. Shah believes improved testing has contributed to increased recognition.
Other infections may coexist with Lyme disease. Clinical evaluation may include Anaplasma, Ehrlichia, Babesia, and other pathogens when appropriate.
Multiple tick exposures can complicate medical histories. Some patients may acquire different infections over time.
FDA clearance does not guarantee insurance reimbursement. Dr. Shah describes ongoing efforts to expand coverage.
Earlier diagnosis matters. Dr. Shah hopes wider access to diagnostic technology will help patients receive timely care.

Learn More About IGeneX and Lyme Disease Testing

For additional information about the technologies discussed in this interview, explore:

About This LIVE from ILADS Interview

Recorded at the 2025 ILADS Conference in San Antonio, Texas, this interview features Dr. Jyotsna Shah, PhD, President and Laboratory Director of IGeneX.

Rich and Dr. Shah discuss the FDA clearance of Lyme ImmunoBlot test kits, the significance of bands 31 and 34, differences between traditional two-tier testing and stand-alone immunoblots, expanded Borrelia antigen coverage, and the importance of considering additional tick-borne infections.

They also explore Babesia testing, the role of wildlife in tick-borne disease transmission, and the possibility of broader access to specialized testing through insurance and local laboratories.

Discover more interviews with leading physicians and researchers through Tick Boot Camp's LIVE from ILADS podcast series.

Better testing can help create a path toward earlier answers, informed treatment decisions, and better patient care.