A 30 years old female has chronic diarrhea, mouth ulcers and skin tags. She complains of visual problems, low back pain and morning stiffness. Investigations: ESR & CRP raised, Hgb 10mg/dl. What is the most probable diagnosis?

The key is E. Seronegative arthritis. [Chronic diarrhea, mouth ulcers and skin tags are features of IBD. There is a well known association between IBD and seronegative arthritis (particularly AS). Here low back pain, visual problem, morning stiffness, raised ESR and CRP, low hemoglobin indicates the diagnosis of Seronegative arthritis].