Pneumococcal pyomyositis: a patient with diagnostic problems and complications

Area of Science:

• Infectious Diseases
• Rheumatology
• Radiology

Background:

• Pyomyositis is an uncommon intramuscular infection, often challenging to diagnose.
• This report details a case of Streptococcus pneumoniae pyomyositis in a patient with autoimmune markers but no overt connective tissue disease.
• The case involved iliacus, iliopsoas, and gluteus muscles.

Purpose of the Study:

• To report a unique case of Streptococcus pneumoniae pyomyositis.
• To emphasize the diagnostic challenges and potential mimics of connective tissue disease.
• To illustrate the rapid progression and potential complications of undiagnosed pyomyositis.

Main Methods:

• Case report of a patient with severe muscle pain and fever.
• Magnetic resonance imaging (MRI) to assess muscle involvement and disease progression.
• Laboratory investigations including autoimmune antibody titers.

Main Results:

• Streptococcus pneumoniae identified as the causative agent of pyomyositis.
• MRI revealed rapid progression from muscle edema to abscess formation within 10 days.
• Patient presented with elevated antinuclear and antiphospholipid antibodies without clinical connective tissue disease.
• Delayed diagnosis led to the development of osteomyelitis and sacroiliitis.

Conclusions:

• Pyomyositis should be considered in patients presenting with acute, severe, localized muscle pain and fever.
• Autoimmune markers may be present in pyomyositis without underlying connective tissue disease.
• Timely diagnosis and treatment of pyomyositis are essential to minimize morbidity and prevent complications.