The key difference between polymyositis and polymyalgia rheumatica is that polymyositis is an inflammatory muscle disease in which tenderness or weakness of muscles is more prominent, while polymyalgia rheumatica is an inflammatory muscle disease in which muscle pain or stiffness without weakness is most prominent.
Inflammatory muscle diseases involve chronic muscle inflammation, muscle weakness, and muscle pains. They are a group of muscle diseases. It is also called inflammatory myopathy. All these inflammatory muscle diseases generally cause muscle weakness. Some well-known examples are polymyositis, dermatomyositis, inclusion body myositis, and necrotizing autoimmune myopathy.
CONTENTS
1. Overview and Key Difference
2. What is Polymyositis
3. What is Polymyalgia Rheumatica
4. Similarities – Polymyositis and Polymyalgia Rheumatica
5. Polymyositis vs Polymyalgia Rheumatica in Tabular Form
6. Summary – Polymyositis vs Polymyalgia Rheumatica
What is Polymyositis?
Polymyositis is an uncommon inflammatory muscle disease that causes muscle weakness on both sides of the body. People suffering from this condition face difficulties in climbing stairs, rising from a seated position, lifting objects, and reaching overhead. Polymyositis most commonly affects adults between the ages of 30s, 40s, and 50s. Moreover, women are affected more than men. The exact cause of polymyositis is not still known. But it is believed that autoimmune condition plays an important role. The risk of polymyositis increases if people are suffering from rheumatoid arthritis, lupus, or Sjogren’s syndrome.
Figure 01: Polymyositis
The symptoms of polymyositis may include muscle stiffness, muscle weakness, particularly in the belly, shoulders, upper arms, and hips, joint pain and stiffness, trouble catching the breath, problems with swallowing, and irregular heart rhythms. Complications of polymyositis include difficulty in breathing, aspiration pneumonia, and breathing problems. Polymyositis can be diagnosed through blood tests, electromyography, magnetic resonance imaging (MRI), and muscle biopsy. Furthermore, treatment options for polymyositis include medications (corticosteroids, corticosteroids sparing agent, rituximab), therapy (physical therapy, speech therapy, and dietetic assessments), and surgical and other procedures (intravenous immunoglobulin).
What is Polymyalgia Rheumatica?
Polymyalgia rheumatica is an inflammatory muscle disorder that causes muscle pain and stiffness without weakness. This pain and stiffness are especially observed in the shoulders and hips. People who develop this condition are usually older than 65. It rarely affects people under 50. This condition is also related to another inflammatory condition called giant cell arteritis. It is possible to have both these conditions together.
The symptoms of polymyalgia rheumatica may include aches or pain in the shoulders, aches or pain in the neck, upper arms, shoulders, hips, or thighs, stiffness in the affected areas, pain or stiffness in the wrists, elbows, or knees, mild fever, fatigue, malaise, loss of appetite, unintended weight loss, and depression. Polymyalgia rheumatica is usually caused by genetics and exposure to the environment. The complication may include difficulties getting out of bed, combing hair, bathing, and getting dressed.
Polymyalgia rheumatica can be diagnosed through physical examination, neurological examination, blood tests, and imaging tests (MRI). Furthermore, treatment options for polymyalgia rheumatica include medications (corticosteroids, calcium and vitamin D, methotrexate), physical therapies, lifestyle, and home remedies (eat a healthy diet, exercise regularly, get enough rest, and use assistive devices).
What are the Similarities Between Polymyositis and Polymyalgia Rheumatica?
- Polymyositis and polymyalgia rheumatica are two inflammatory muscle diseases.
- Both diseases cause muscle stiffness.
- Both diseases affect the quality of life of people.
- Women are more affected by both conditions.
- Both diseases can be diagnosed through blood tests and imaging tests.
- They are treated through medications like corticosteroids and therapies.
What is the Difference Between Polymyositis and Polymyalgia Rheumatica?
Polymyositis is an inflammatory muscle disease that causes weakness in muscles without pain, while polymyalgia rheumatica is an inflammatory muscle disease that causes symmetrical painful muscles. Thus, this is the key difference between polymyositis and polymyalgia rheumatica. Furthermore, polymyositis is a destructive inflammatory muscle disease, but polymyalgia rheumatica is not a destructive inflammatory muscle disease.
The below infographic presents the differences between polymyositis and polymyalgia rheumatica in tabular form for side-by-side comparison.
Summary – Polymyositis vs Polymyalgia Rheumatica
Inflammatory muscle diseases usually cause muscle inflammation, weakness, and pain. Polymyositis and polymyalgia rheumatica are two inflammatory muscle diseases. Both these conditions affect the quality of life of people. Polymyositis causes weakness in muscles without pain, while polymyalgia rheumatica causes symmetrical painful muscles and stiffness without weakness. So, this is the key difference between polymyositis and polymyalgia rheumatica.
Reference:
1. “Polymyositis: Symptoms, Causes & Treatments.” Cleveland Clinic.
2. “Polymyalgia Rheumatica.” Mayo Clinic, Mayo Foundation for Medical Education and Research.
Image Courtesy:
1. “Polymyositis HE” By Jensflorian – Own work (CC BY-SA 3.0) via Commons Wikimedia