Erythema induratum is a

panniculitis Panniculitis is a group of diseases whose hallmark is inflammation of subcutaneous adipose tissue (the fatty layer under the skin – panniculus adiposus). Symptoms include tender skin nodules, and systemic signs such as weight loss and fatigu ...

on the calves. It occurs mainly in women, but it is very rare now. Historically, when it has occurred, it has often been

concomitant Concomitance is the condition of accompanying or coexisting. A concomitant is something that accompanies something else. Concomitant or concomitance may refer to: * Concomitance (doctrine), a Christian doctrine * Concomitant (classical algebraic ...

with cutaneous tuberculosis, and it was formerly thought to be always a reaction to the TB bacteria. It is now considered a

that is not associated with just a single defined pathogen. The

medical eponym Medical eponyms are terms used in medicine which are named after people (and occasionally places or things). In 1975, the Canadian National Institutes of Health held a conference that discussed the naming of diseases and conditions. This was repo ...

Bazin disease was historically synonymous, but it applies only to the tuberculous form and is dated.

Pathophysiology

Predisposing factors include abnormal amount of subcutaneous fat, thick ankles and abnormally poor arterial supply. Abnormal arterial supply causes low-grade ischemia of ankle region. The ankle skin becomes sensitive to temperature changes. When weather is cold, ankle is cold, blue and often tender. In hot weather, ankle becomes hot, edematous, swollen and painful.

Chilblains Chilblains, also known as pernio, is a medical condition in which damage occurs to capillary beds in the skin, most often in the hands or feet, when blood perfuses into the nearby tissue resulting in redness, itching, inflammation, and possibly ...

may be present. On

palpation Palpation is the process of using one's hands to check the body, especially while perceiving/diagnosing a disease or illness. Usually performed by a health care practitioner, it is the process of feeling an object in or on the body to determine ...

, small superficial and painful nodules are felt. They break down to form small and multiple ulcers. Fresh crops of nodules appear in periphery of ulcer and ultimately break down. In nodular stage, pain is present; while it subsides in ulcerative stage.

Diagnosis

Mainly clinical.

Eponym

The name ''Bazin disease'' honors

Pierre-Antoine-Ernest Bazin Pierre-Antoine-Ernest Bazin (20 February 1807 – 14 December 1878) was a French physician and dermatologist born in Saint-Brice-sous-Forêt. His brother, Antoine-Pierre-Louis Bazin (1799-1863), was a noted Sinologist. In 1828 he started work as ...

.P. A. E. Bazin. Leçons théoriques et cliniques sur la scrofule, considérée en ellemême et dans ses rapports avec la syphilis, la dartre et l'arthritis. 2nd edition, Paris, 1861. Page 145 and 501.

Additional images

File:An introduction to dermatology (1905) erythema induratum.jpg

References

External links

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PatientPlus
Mycobacterium-related cutaneous conditions {{Cutaneous-infection-stub