Ulceration and necrosis - an overview

This chapter, which is set out as below, signposts to the many and varied conditions that can cause ulceration and necrosis. 

Predominantly affecting lower legs and/or feet

• Leg ulcers

• Pyoderma gangrenosum (rapidly enlarging, painful ulcer with blue-purple undermined edge)

• Vasculitis (any of - palpable purpura, ulcers, necrosis, nodules, livedo reticularis)

• ​Necrobiosis lipoidica (shins / sharply demarcated, atrophic, yellowish patches or plaques / lesions grow with an erythematous edge, and a centre that becomes shiny and atrophic with prominent telangiectasia / occasionally ulcerate)

• Localised bullous pemphigoid (can be localised to the lower legs and feet / large tense blisters)
  

Hands / feet (in addition to the above)

• Cold-induced - refer to the general dermatology diagnostic tool

• Neutrophilic dermatosis of the (dorsal) hands (rare / blue-grey pustular or ulcerative plaques and nodules on the dorsal hands)
  

Mucosal surfaces (in some conditions both sites may be affected)

• Mouth - refer to the chapter Oral lesions and other dermatological conditions of the mouth

• Genitalia - refer to the chapter Genital conditions - an overview
  

Other localised conditions (usually)

Infection

• Herpes zoster syn. shingles (painful / closely grouped red papules, rapidly becoming vesicular and then pustular, develop in a continuous or interrupted band in the area of one or occasionally two and, rarely, more contiguous dermatomes / lesions can become necrotic)

• Stevens-Johnson syndrome (occasionally life-threatening / ulceration, crusting and necrosis of oral mucosa, and eye involvement / skin: painful, confluent erythema with local erosions and blisters, and sheet-like areas of skin loss - usually < 10% of the body affected, but can be up to 30%)

• Necrotising fasciitis (can be mistaken for cellulitis / dusky-violaceous areas along with erythema / the level of pain and tenderness, or systemic upset, is out of proportion to the physical signs)

• ​Ecthyma (in developed countries it mainly affects children, in countries with poorer hygiene and nutrition any age can be affected / the lesion is characterised by the formation of adherent crusts, beneath which ulceration develops)

• Leishmaniasis (typically exposed sites eg face and extremities / a red-brown nodule or plaque, or sometimes multiple papules / varying amounts of crust, with an underlying ulcer / lesions heal with scarring)

• Mycobacterial infections (various presentations)

• Opportunistic infections (arise as a result of a weakened immune system / can cause ulcerated and necrotic lesions)

• Anthrax (usually affects the hands, face and neck / lesions have a necrotic centre with an outer rim of small bullae and non-pitting oedema)

Other

• Non-accidental injury (child abuse)

• Dermatitis artefacta - a type of self-harm (an unusual or inconsistent history / odd shaped lesions / no or minimal surrounding erythema)

• Acne fulminans (severe inflammatory acne on the trunk associated with systemic symptoms such as fever and arthritis)

• Cutaneous T-Cell lymphoma (various presentations - can be localised or occasionally widespread)

• Drug eruptions (including warfarin necrosis - onset usually within 2-5 days of warfarin therapy / most common sites - abdomen, hips, buttocks, thighs, breasts / pain and purpura, which over a few days becomes bluish-black with a red rim. Tissue necrosis follows)

More generalised conditions (usually)

• Meningococcal septicaemia (and other causes of septicaemia)

• Toxic epidermal necrolysis (life-threatening / ulceration, crusting and necrosis of oral mucosa, and eye involvement / skin: painful, confluent erythema with local erosions and blisters, and sheet-like areas of skin loss - usually > 30% of the body is affected, but can be less)

• Erythema multiforme (patient relatively well / often distal extremities, especially the hands / targetoid lesions with a central dark red zone, a mid pale zone and an outer ring of erythema / can be associated with blisters, and occasionally crusting and ulceration of lips)

• Bullous (blistering) disorders (as blisters rupture they leave behind erosions and sometimes ulcers)

• Pityriasis lichenoides acuta (predominantly children and young adults / trunk, buttocks, proximal limbs most commonly affected sites / lesions are numerous, discrete, and tend to arise in crops / initial lesion is a pink papule, which rapidly becomes vesicular and develops a haemorrhagic crust)

• Lymphomatoid papulosis (recurrent crops of papular, papulonecrotic or nodular lesions)

• Herpes zoster (can be widespread in immunocompromised patients)

• Cutaneous T-Cell lymphoma (various presentations - can be localised or occasionally widespread)