Differential Diagnosis for Soft Tissue Attenuation and Mass at Pubic Symphysis
- Single Most Likely Diagnosis
- Chronic osteomyelitis or pubic symphysis osteomyelitis with a soft tissue abscess: This is likely due to the presence of internal gas within the mass, which suggests an infectious or inflammatory process, and the slow growth over time. The involvement of the osteoarthritic pubic symphysis further supports this diagnosis.
- Other Likely Diagnoses
- Soft tissue tumor (e.g., sarcoma) arising from the pubic symphysis: Although less common, the relatively well-circumscribed nature of the mass and its slow growth could suggest a tumor. The presence of internal gas is less typical but could be seen in certain tumor types, such as those with necrosis or fistula formation.
- Bursitis or soft tissue cyst related to the osteoarthritic pubic symphysis: This could explain the soft tissue attenuation and mass effect, especially if there's a significant inflammatory component. However, the presence of internal gas would be unusual.
- Do Not Miss Diagnoses
- Abscess or infected hematoma related to a urinary tract infection or prostatitis: Given the proximity to the urinary bladder and the potential for urinary tract infections in elderly males, an infectious process originating from the urinary system must be considered, especially if there are symptoms suggestive of a urinary tract infection.
- Gas-producing infection (e.g., emphysematous osteomyelitis or soft tissue infection): This is a critical diagnosis to consider due to its potential for rapid progression and severe consequences if not promptly treated.
- Rare Diagnoses
- Soft tissue metastasis to the pubic symphysis: Although rare, metastatic disease can present in unusual locations, and the presence of a mass with internal gas could be seen in the context of a metastatic lesion with necrosis.
- Primary bone tumor of the pubic symphysis with soft tissue extension: Tumors such as chondrosarcoma or osteosarcoma could present in this manner, although they are less common and might not typically show internal gas.