Differential Diagnosis for 34-year-old Female with Bilateral Anterior Knee Pain, Right Wrist Pain, and Right Elbow Pain

Single Most Likely Diagnosis

• Repetitive Strain Injury or Overuse Syndrome: This diagnosis is likely due to the acute onset of bilateral anterior knee pain, along with pain in the right wrist and elbow, suggesting a pattern of overuse or repetitive strain, possibly related to work, sports, or other activities.

Other Likely Diagnoses

• Rheumatoid Arthritis (RA): Although less common in this age group without other systemic symptoms, RA can present with symmetric joint pain and should be considered, especially if there's morning stiffness or other signs of inflammation.
• Osteoarthritis (OA): Uncommon at this age but possible, especially if there's a history of trauma, obesity, or familial predisposition. The distribution of pain could suggest a pattern seen in OA, though it's less typical for someone so young.
• Tendinitis/Tendinosis: Conditions like patellar tendinitis (knee), lateral epicondylitis (elbow), and De Quervain's tenosynovitis (wrist) could explain the pain, given their association with overuse and repetitive activities.

Do Not Miss Diagnoses

• Septic Arthritis: Although unlikely without systemic symptoms like fever, any joint pain could potentially be due to septic arthritis, which is a medical emergency requiring prompt diagnosis and treatment.
• Lyme Disease: If the patient lives in an area endemic for Lyme disease and has been exposed to ticks, Lyme arthritis could be a consideration, especially if other symptoms like rash or systemic illness are present.
• Gout or Pseudogout: Acute onset of joint pain could suggest crystal arthropathy, though the distribution and lack of systemic symptoms make this less likely.

Rare Diagnoses

• Sarcoidosis: A systemic disease that can cause joint pain among other symptoms, though it's rare and would typically be accompanied by other systemic signs.
• Hemochromatosis: A genetic disorder leading to iron overload, which can cause joint pain similar to OA, but it's rare and would likely have other associated findings like skin pigmentation changes or liver disease.
• Relapsing Polychondritis: A rare autoimmune disorder that could cause joint pain, among other symptoms like cartilage and connective tissue inflammation, but it's very uncommon and would likely present with additional systemic symptoms.