Final answer:
Erythema induratum is a skin condition with red nodules typically on the legs or face, linked to subcutaneous fat cell inflammation and often associated with tuberculosis. It differs from erythema nodosum, which is a related but distinct condition with tender bumps commonly on the shins. Proper diagnosis is essential due to similarities with other skin conditions like eczema or psoriasis.
Step-by-step explanation:
Erythema induratum is a skin condition that typically presents with red nodules, usually found on the legs or face. It is a form of panniculitis, which is due to inflammation in the subcutaneous fat cells of the hypodermis. These nodules can appear similar to erythema nodosum, except that erythema nodosum is a condition that is characterized by tender red bumps, particularly on the shins, and is often associated with other systemic diseases. Erythema induratum is associated with the vasculitis seen in tuberculosis and can be considered a hypersensitivity reaction.
The term erythema refers to redness at the site of inflammation, usually due to dilation of blood vessels in the area to help bring in white blood cells. The etiology, or the cause of disease, may vary, but in the case of erythema induratum, it is commonly an etiologic agent like a bacteria causing infection.
This condition can be confused with other skin disorders such as eczema, which is an allergic reaction manifesting as dry, itchy patches of skin, or psoriasis, which presents with thick, red skin with silvery scales. Therefore, correct diagnosis and treatment by a healthcare professional is crucial.