Bullous Erythema Migrans: A Blistering Lyme Disease Rash
Blistering Lyme disease rash
An uncommon form of erythema migrans
May delay diagnosis and treatment
Bullous erythema migrans, sometimes referred to as bullous Lyme disease, is an uncommon blistering Lyme disease rash that can be mistaken for herpes infection, shingles, spider bites, Sweet syndrome, or other skin disorders. Although erythema migrans is often associated with a classic bull’s-eye appearance, atypical presentations can complicate diagnosis.
Atypical Lyme Disease Rashes
Several reports have found urticarial, linear, granulomatous, and bullous erythema migrans presentations associated with Lyme disease, as well. As this case series highlights, “several erythema migrans variants have been reported, which may result in misidentification as well as delayed diagnosis and treatment.”1
In their article, “Vesiculobullous Lyme disease: A case series,” the authors describe three cases where an erythema migrans rash presented as a blistering rash, also referred to as bullous erythema migrans. (Typically, an erythema migrans rash is more likely to present as a flat rash.)
Can Lyme Disease Cause Blisters?
Yes. Although uncommon, Lyme disease can present as bullous erythema migrans, a blistering form of the characteristic Lyme disease rash.
Three Cases of Bullous Erythema Migrans
“All 3 cases exhibited rapidly developing bullous lesions in the presence of systemic symptoms, ranging from fatigue and malaise to fever,” the authors wrote.
Initially, the lesions were attributed to Sweet syndrome, herpes simplex virus infection, varicella-zoster virus infection, a spider bite, or atypical Lyme disease. (Sweet syndrome is a group of non-infectious disorders with neutrophilic infiltration of the skin.)
Case 1: 54-year-old woman presented with an enlarging red lesion that grew progressively darker. The authors described “a 10-cm (4 inches) edematous purpuric plaque with vesiculobullous.”
Case 2: 49-year-old woman presented with an enlarging, darkening lesion on the posterior aspect of her ankle. The authors described a “9-cm vesiculobullous plaque with erythema.”
Case 3: 65-year-old woman presented with a red, swollen, painful plaque on the left side of her flank.
To view case reports, along with photos of each rash, click here.
The case series includes photographs of bullous erythema migrans lesions, illustrating how Lyme disease rashes can differ from the classic bull’s-eye appearance.
In all three cases, laboratory tests were subsequently positive for Lyme disease and were successfully treated.
“Clinicians in Lyme endemic areas should be aware that Lyme disease might exhibit a broad range of clinical and histologic findings, including bullous presentations.”
Because bullous erythema migrans may resemble shingles, herpes infection, spider bites, or Sweet syndrome, Lyme disease may not be immediately recognized.
It can be challenging to diagnose a blistering erythema migrans rash. Tests for Lyme disease may not be positive at the time the lesions appear. And the histopathologic findings for blistering erythema migrans rash can resemble other diseases.
“Histopathologic features of Lyme disease often include a superficial and deep perivascular and interstitial infiltrate consisting of lymphocytes and plasma cells, and may include eosinophils and neutrophils,” wrote the authors.
“Clinicians in Lyme endemic areas should be aware that Lyme disease might exhibit a broad range of clinical and histologic findings, including bullous presentations,” the authors urge.
Therefore, “a low threshold for considering Lyme disease in the differential diagnosis of bullous lesions is warranted in endemic areas with empiric treatment and follow-up serologies for disease confirmation.”
For more examples of atypical Lyme rashes, see Lyme Rash Misdiagnosis: The Bull’s-Eye Isn’t Always Present.
Additional examples can be found in our guide to What Does a Lyme Disease Rash Look Like?.
Frequently Asked Questions
What is bullous erythema migrans?
Bullous erythema migrans is a blistering form of the Lyme disease rash that differs from the classic bull’s-eye appearance.
Can Lyme disease cause a blistering rash?
Yes. Although uncommon, Lyme disease can present as bullous erythema migrans, a blistering form of the characteristic Lyme disease rash.
Does erythema migrans always look like a bull’s-eye rash?
No. Lyme disease rashes can appear blistering, linear, granulomatous, solid, or otherwise atypical.
Clinical Takeaway
Clinicians practicing in Lyme-endemic areas should recognize that erythema migrans does not always present as a classic bull’s-eye rash. Bullous erythema migrans may mimic shingles, herpes infection, spider bites, Sweet syndrome, and other dermatologic conditions, potentially delaying diagnosis and treatment if Lyme disease is not considered.
Related Articles:
Lyme disease skin rash puzzles doctors, leads to misdiagnosis
Podcast: What does a Lyme disease rash look like?
How the incidence of an EM rash can be inflated
Lyme Rash Misdiagnosis: The Bull’s-Eye Isn’t Always Present
References:
- Doughty H, O’Hern K, Barton DT, Carter JB. Vesiculobullous Lyme disease: A case series. JAAD Case Rep. 2022;24:56-58. doi:10.1016/j.jdcr.2022.04.001.
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
My rash presented itself as a huge hour glass shape all over my torso. My primary care physician diagnosed me with a fungus. I told him he was wrong and to test my for Lyme. Sure enough my bloodwork confirmed my suspicions.