Differential Diagnosis for 40yo M with Pain and Swelling at the Base of the 1st MTP
- Single most likely diagnosis
- Gout: The patient's presentation of acute onset pain and swelling at the base of the 1st MTP, a common site for gouty attacks, makes this a highly likely diagnosis. The fact that the patient has no known injury to the foot (NKI) and attempted to treat a callus without relief also points towards an inflammatory or crystalline arthropathy like gout.
- Other Likely diagnoses
- Sesamoiditis: Inflammation of the sesamoid bones or their tendons could cause pain and swelling at the base of the 1st MTP, especially if the patient has been applying pressure or friction to the area while trying to remove a callus.
- Bursitis: Inflammation of a bursa near the 1st MTP could cause similar symptoms, possibly due to repetitive motion or pressure from the pumice stone.
- Osteoarthritis: Although less likely given the acute presentation, osteoarthritis of the 1st MTP joint could cause pain and swelling, especially if the patient has a history of trauma or repetitive stress to the joint.
- Do Not Miss diagnoses
- Septic Arthritis: Although less common, septic arthritis is a medical emergency that requires prompt diagnosis and treatment. The patient's attempt to treat a callus with a pumice stone could have introduced bacteria into the joint, making this a critical diagnosis not to miss.
- Cellulitis or Soft Tissue Infection: An infection of the soft tissues surrounding the 1st MTP could cause pain, swelling, and redness, and could be a consequence of the patient's attempt to treat the callus.
- Deep Vein Thrombosis (DVT): While less directly related to the symptoms at the 1st MTP, DVT can cause swelling and pain in the leg and should be considered, especially if there are other risk factors present.
- Rare diagnoses
- Pseudogout (Calcium Pyrophosphate Deposition Disease): Similar to gout, but caused by calcium pyrophosphate dihydrate crystals, this condition could cause acute inflammatory arthritis of the 1st MTP.
- Rheumatoid Arthritis: Although typically a polyarticular condition, rheumatoid arthritis could present with monoarticular symptoms, including pain and swelling at the 1st MTP.
- Neuroma: A neuroma, such as a Morton's neuroma, could cause pain and swelling in the foot, but typically presents with more specific symptoms like numbness or tingling between the toes.