A 27 Year Old Man Presents With Several Red, Tender Subcutaneous Nodules On The Anterior Lower Legs

A biopsy of one of several red, tender, subcutaneous nodules from the anterior lower legs of a
27-year-old man is obtained by a dermatologist.
On histopathology, she sees a panniculitis (inflammation of subcutaneous fat) with widening of tissue septa from edema, increased neutrophils, and fibrin exudation.
Which of the following diseases is often present in someone with these nodules?

(A) Acne vulgaris
(B) Crohn’s disease
(C) Eczema
(D) Pancreatitis
(E) Psoriasis

Answer And Discussion:


The correct answer is B.
This patient has erythema nodosum, an inflammation of subcutaneous fat that is often accompanied by fever and malaise that is described clinically and pathologically in the question stem. The exact
mechanism is unknown, but it often occurs together with inflammatory bowel disease (Crohn’s disease or ulcerative colitis), sarcoidosis, certain drugs (such as oral contraceptives
and sulfonamides), certain malignant neoplasms, and certain infections (such as tuberculosis,
β-hemolytic streptococci, coccidioidomycosis, histoplasmosis, and leprosy).

Answer A is incorrect. Acne vulgaris is a disorder of the epidermis that has both inflammatory and non inflammatory variants. It is associated with the bacterium Propionibacterium acnes.

Answer C is incorrect. Eczema is an inflammatory skin disorder that is associated with contact allergies, asthma, ultraviolet light exposure, repeated physical skin rubbing, and certain drugs. It is not associated with erythema nodosum.

Answer D is incorrect. Pancreatitis, which is associated with many cases of biliary tract disease and alcoholism, is not associated with erythema nodosum.

Answer E is incorrect. Psoriasis is a nonpruritic inflammatory skin disorder associated with arthritis, enteropathy, spondylitic disease, and certain HLA types, including HLA-B27, HLA-13, and HLA-17.