Differential Diagnosis for Juan Menor
Single Most Likely Diagnosis
- Osteoarthritis (OA): This is the most likely diagnosis given Juan's age, symptoms of joint pain in both knees, and the duration of the pain. OA is a common condition in adults over 40, and the knee is one of the most frequently affected joints. Juan's occupation as an air traffic controller, which may involve prolonged periods of sitting, and his hobbies of playing badminton and tennis, which can put additional stress on the knee joints, also support this diagnosis.
Other Likely Diagnoses
- Rheumatoid Arthritis (RA): Although less likely than OA given the information, RA is a possibility, especially if Juan experiences morning stiffness lasting more than an hour, or if there are signs of systemic illness. The symmetric nature of the joint pain (both knees) could also suggest RA.
- Meniscal Tear or Ligament Sprain: Given Juan's active participation in sports like badminton and tennis, an acute injury such as a meniscal tear or ligament sprain could be a cause of his knee pain. However, the gradual onset over 3 months makes this less likely.
- Gout: Gout is another form of arthritis that could cause knee pain, especially if Juan has had previous episodes of sudden, severe joint pain. However, gout typically affects one joint at a time, and the absence of such episodes in the history makes this less likely.
Do Not Miss Diagnoses
- Septic Arthritis: Although unlikely given the chronic nature of Juan's symptoms, septic arthritis is a medical emergency that requires prompt diagnosis and treatment. It typically presents with sudden onset of pain, swelling, and decreased range of motion in a single joint, often accompanied by systemic signs of infection.
- Lyme Disease: If Juan has been exposed to ticks (e.g., through outdoor activities), Lyme disease could be a consideration, especially if he has a history of traveling to endemic areas. Lyme arthritis can cause knee pain and swelling, usually in one knee.
Rare Diagnoses
- Psoriatic Arthritis: This condition is less common and typically occurs in individuals with psoriasis. It can cause joint pain, swelling, and stiffness, but the absence of skin symptoms in Juan's history makes this less likely.
- Hemochromatosis: A genetic disorder leading to iron overload, which can cause arthritis among other symptoms. It's rare and would be considered if Juan had other signs of iron overload or a family history of the condition.
- Wilson's Disease: A rare genetic disorder that leads to copper accumulation in the body, which can cause arthritis, among other symptoms. It's very unlikely but would be considered in the differential if Juan had other systemic symptoms or a family history of the disease.