In simple words: Erythema nodosum is a skin problem causing red, painful bumps, usually on the lower legs.It happens because of an underlying issue like an infection or other medical condition.

Erythema nodosum is an inflammatory skin condition characterized by tender, red nodules (bumps) usually appearing on the shins and sometimes other areas.It's typically caused by an underlying condition like an infection (bacterial, fungal, viral), inflammatory bowel disease, sarcoidosis, or certain medications. The nodules are usually painful and may be accompanied by fever and malaise. Diagnosis involves physical examination and may include tests to identify the underlying cause.

Example 1: A 30-year-old female presents with painful, red nodules on her shins. She also reports fever and fatigue.Laboratory testing reveals a streptococcal infection.The diagnosis is erythema nodosum secondary to streptococcal infection. Treatment includes antibiotics and supportive care., A 45-year-old male with known Crohn's disease presents with new onset erythema nodosum.His Crohn's disease is managed with medication.The erythema nodosum is considered a manifestation of his underlying inflammatory bowel disease. Treatment focuses on managing the Crohn's disease., A 25-year-old female presents with erythema nodosum. She denies any symptoms of infection or inflammatory bowel disease.Further investigations reveal sarcoidosis.Treatment is initiated to manage the sarcoidosis.

Complete history and physical examination, including assessment of systemic symptoms. Laboratory investigations as needed to determine the underlying etiology (e.g., complete blood count, inflammatory markers, cultures, imaging studies).Documentation of treatment plan and response to therapy.