ALS or Lyme Disease? How to Tell the Difference Before It’s Too Late

Lyme disease is caused by the bacteria, “Borrelia burgdorferi”, and is transmitted to humans through a tick bite. The prognosis is good for Lyme disease, when treated early. 

Have you ever heard of amyotrophic lateral sclerosis (ALS)? It is a neurodegenerative condition that affects the nerve cells. The neurological manifestations of Lyme disease can closely mimic the clinical symptoms of Lyme disease. But, how can we differentiate between the two conditions? In this blog, we will explore the clinical symptoms of both Lyme disease and ALS.

What is ALS?

Amyotrophic lateral sclerosis is a disease that affects the motor neurons that leads to the degeneration of nerve cells. ALS is also known as Lou Gehrig’s disease. There are two types of ALS.

• Sporadic: This type accounts for 90% of the ALS cases. Sporadic cases occur without a genetic cause or a familial history.
• Familial: Inherited form affects a small population. 

Clinical symptoms:

• Twitching of muscles
• Fatigue
• Slurred speech
• Difficulty in breathing and swallowing

When the neurons degenerate, muscle atrophy and fasciculations occur. Eventually, the brain will lose the ability to control voluntary movements. 

Risk factors:

• High blood pressure
• Smoking
• Age (B/w 55-75)
• Male predominance

How is ALS diagnosed?

The clinical symptoms can be assessed by conducting a physical examination and analysing the medical history. A neurological examination can help to analyse the strength and response of the muscles. Magnetic resonance imaging (MRI) and radiowaves can be used to capture the images of brain & spinal cord. Electromyography (EMG) can be used to evaluate the functioning of nerves and muscles. Other tests include blood tests, urine tests, and biopsy of muscles. 

What are the clinical symptoms of Lyme disease?

In the initial stage, erythema migrans or skin rashes can occur. Within few weeks, the spot expands and forms a circular or oval-shaped rash. The rashes may appear in the form of concentric rings or bull’s eye rashes. It has been estimated that erythema migrans occur in 70-80% of individuals. 

When the infection starts to spread, the lesions appear on distinct parts of your body. Other symptoms include fever, fatigue, joint tenderness, Bell’s palsy, swelling of lymph nodes, etc.

Other clinical symptoms include,

• Tingling sensation
• Palpitations
• Trouble breathing
• Inflammation of the nervous system

Is your muscle weakness a sign of ALS or Lyme disease? How to distinguish between the two conditions?

Muscle weakness can be a clinical symptom of either ALS or Lyme disease. The diagnosis of both the conditions may be confusing even for an expert professional. Lyme disease can be diagnosed at an early stage using blood tests. A cerebrospinal fluid test can be used to detect Lyme disease. 

Amyotrophic Lateral Sclerosis (ALS) and Lyme disease are two conditions that usually come under the spotlight. Although they may appear with similar symptoms, it is essential to know their distinction to diagnose and treat them on time.

ALS is a neurodegenerative disease, which is progressive and affects the motor nerves. Lyme disease is a vector-borne disease, which is caused by the Borrelia burgdorferi. It may cause weakness of the muscles, facial palsy, pain, tiredness, joint pain, headache and neuroborreliosis. Notably, the weakness in Lyme disease can be acute or intermittent and usually respond to antibiotics.

There are different approaches to diagnosis. The diagnosis of ALS can be confirmed by electromyography (EMG) and MRI. Serological testing (ELISA and Western blot) or lumbar puncture of the cerebrospinal fluid or a history of the characteristic rash of erythema migrans will confirm Lyme disease.

The distinction made at the right moment is critical. There is still no cure to ALS, and its development inevitably continues, whereas Lyme disease can be cured, especially in the initial phases. When you have unrelated muscle weakness, particularly those with a history of tick exposures or those with varying symptoms, you should seek medical help at the early stage itslef. Early diagnosis can result in a life-changing difference.

How can ALS be cured?

Normally, a treatment cannot cure or reverse the damage of ALS. The Food and Drug Administration (FDA) has approved two drugs for managing the clinical symptoms of ALS. A drug called Riluzole can increase the life expectancy of patients to 25%. Edaravone is another drug that can be administered orally or intravenously for 2 weeks. 

Patients with ALS experience difficulty in breathing. In this case, mechanical ventilation can be provided to help with breathing. In some cases, tracheostomy is performed, where a hole is created at the front of the neck that helps the patients to breathe properly. Regular exercises can maintain the fitness, cardiovascular system, mobility and helps in relieving pain. 

Conclusion:

It is difficult to distinguish ALS and Lyme disease due to overlapping clinical symptoms, such as muscle weakness, facial palsy, etc. Even though the clinical symptoms are similiar, underlying cause and treatment modalities are different. Early detection of the condition and appropriate treatment strategies can lead to improved treatment outcomes.

References:

1. Johns Hopkins Medicine. Amyotrophic lateral sclerosis (ALS) [Internet]. Baltimore: Johns Hopkins Medicine; [cited 2025 Jul 4]. Available from: https://www.hopkinsmedicine.org/health/conditions-and-diseases/amyotrophic-lateral-sclerosis-als
2. National Institute of Neurological Disorders and Stroke (NINDS). Amyotrophic lateral sclerosis (ALS) [Internet]. Bethesda (MD): National Institute of Neurological Disorders and Stroke; [cited 2025 Jul 4]. Available from: https://www.ninds.nih.gov/health-information/disorders/amyotrophic-lateral-sclerosis-als
3. Centers for Disease Control and Prevention. Signs & symptoms of Lyme disease [Internet]. Atlanta (GA): Centers for Disease Control and Prevention; [cited 2025 Jul 4]. Available from: https://www.cdc.gov/lyme/signs-symptoms/index.html
4. Amyotrophic Lateral Sclerosis (ALS) vs. Lyme Disease [Internet]. ALS – online®. [cited 2025 Jul 4]. Available from: https://www.als.net/news/als-vs-lyme-disease/
5. Mayo Clinic. Amyotrophic lateral sclerosis: Diagnosis & treatment [Internet]. Rochester (MN): Mayo Clinic; [cited 2025 Jul 4]. Available from: https://www.mayoclinic.org/diseases-conditions/amyotrophic-lateral-sclerosis/diagnosis-treatment/drc-20354027