A 19-year-old man presents to his GP with a 2-month history of lower back pain and stiffness. The pain is intermittent, achy, and usually worse in the morning than it is later in the day or evening. He has also noticed a progressive decrease in flexibility in the back, eg flexing to tie laces etc. The pain sometimes awakens him at night. It is improved with exercise. He also reports a several-month history of low grade malaise, and loss of appetite. The patient has no history of rash. He does not have any known chronic medical conditions. He takes one multivitamin per day. He has never smoked, but he does drink an occasional glass of wine with dinner. There is no significant family history of disease.
On physical examination, the patient has a blood pressure of 125/67 mm Hg and a heart rate of 60 bpm, (taken due to the malaise) The patient has no photophobia, or eye redness. On examination of the back, flexion of the lumbar spine is clearly decreased when the patient attempts to bend down to touch his toes. He also has pain and limited range of motion with rotation and lateral flexion at the lumbar spine. He feels he can't get a big enough breath in. He is awaiting a blood test results for Rheumatoid factor , ESR and a genetic marker his GP said.
Possible diagnoses are
2. Spinal Stenosis
4. Ankylosing Spondylitis
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