Differential Diagnosis for Medial Left Foot/Big Toe Pain

• Single most likely diagnosis
  • Gout: The patient's presentation of acute, severe, atraumatic pain in the medial foot/big toe, along with redness and swelling, is highly suggestive of gout. The pain worsening with toe bending also aligns with gout, as movement can exacerbate the condition.
• Other Likely diagnoses
  • Cellulitis: The redness and swelling could indicate a skin infection like cellulitis, especially if there's a history of trauma or a break in the skin that introduced bacteria.
  • Sesamoiditis: Inflammation of the sesamoid bones under the first metatarsal bone could cause pain in the big toe area, especially with activities that involve bending the toes.
  • Bursitis: Inflammation of a bursa near the big toe could cause pain, redness, and swelling, particularly if the bursa is irritated by movement or pressure.
• Do Not Miss (ddxs that may not be likely, but would be deadly if missed.)
  • Osteomyelitis: Although less common, an infection of the bone could present with similar symptoms and would require prompt antibiotic treatment to prevent serious complications.
  • Deep Vein Thrombosis (DVT): While DVT typically presents in the calf, it can occasionally occur in the foot and could be life-threatening if not treated promptly due to the risk of pulmonary embolism.
  • Septic Arthritis: Bacterial infection of the joint could cause severe pain, redness, and swelling, and if not treated promptly, could lead to serious joint damage.
• Rare diagnoses
  • Rheumatoid Arthritis (RA) flare: Although RA is more commonly associated with multiple joint involvement, it could potentially present with a single joint flare, including the big toe.
  • Psoriatic Arthritis: Similar to RA, this condition could cause joint pain and swelling, including in the foot, and is associated with psoriasis.
  • Neuroma: A benign growth of nerve tissue could cause pain, especially if it's located near the big toe and irritated by bending the toes.