Polymicrobial Pyomyositis in a Patient with Suspected Myeloma on ¹⁸F-FDG PET-CT

Area of Science:

• Medical imaging
• Infectious diseases
• Oncology

Background:

• Pyomyositis is a bacterial infection of skeletal muscle, often presenting with non-specific symptoms.
• The patient presented with quadriparesis, anemia, and hypercalcemia, initially suggesting multiple myeloma.
• Diagnostic challenges arise when infections mimic other serious conditions.

Purpose of the Study:

• To highlight the utility of FDG PET-CT in incidentally diagnosing pyomyositis.
• To present a case where advanced imaging aided in identifying an occult infection.
• To emphasize the importance of considering infections in complex presentations.

Main Methods:

• Case report of a 43-year-old male patient.
• Clinical presentation including quadriparesis, anemia, and hypercalcemia.
• Diagnostic workup utilizing Fluorodeoxyglucose Positron Emission Tomography-Computed Tomography (FDG PET-CT).

Main Results:

• FDG PET-CT revealed findings consistent with pyomyositis, an unexpected diagnosis.
• The imaging finding of pyomyositis was incidental to the initial diagnostic workup for other conditions.
• Diagnosis of pyomyositis led to appropriate and effective treatment.

Conclusions:

• FDG PET-CT can be a valuable tool for detecting occult infections like pyomyositis.
• Incidental findings on FDG PET-CT can significantly alter patient management and treatment strategies.
• This case underscores the importance of comprehensive interpretation of imaging studies in complex medical scenarios.