Emergency DermatologyDr Daniel HewittDermatologistSkin and Cancer Foundation Westmead
Emergency DermatologyEmergencies are rare in general dermatology but there are certain situations that require prompt management.These include severe drug reactions, severe infections, allergic reactions and severe flares of inflammatory dermatoses.
The following three areas will be briefly discussed.Severe drug reactionsSerious infectionsErythroderma
Serious drug reactionsDrug reactions in the skin are usually innocuous and self- limiting.The most common presentation is of a blotchy erythema predominantly involving the trunk. This may be referred to as a “morbilliform” (measles-like) rash or as a “macuo-papular” rash. This presentation can also be referred to as a toxic erythema, this is discussed in another module.However, medications can produce many other types of skin changes including urticaria, erythema mutliforme, lichenoid changes, pustules, pigmentation, blisters and mucosal changes
The list of medications that can cause drug reactions is extremely long, but the most common medications causing drug reactions are Antibiotics – beta lactams, sulphonamides Anticonvulsants – phenytoin, carbamazepine, lamotrigine Cardiac medications – frusemide, thiazide diuretics, ACE inhibitors Nonsteroidal anti-inflammatories Allopurinol Antiretrovirals
The most serious drug reaction is toxic epidermal necrolysis. A severe type IV hypersensitvity reaction causes widespread skin necrosis and can lead to multiorgan failure and overwhelming sepsis.It needs early recognition, immediate cessation of the offending drug and early intensive supportive management. It is an emergency.Important signs of a potentially more serious drug reaction are fever and systemic upset mucous membrane involvement targetoid lesions with central duskiness or blistering skin pain and tenderness blistering and shedding of sheets of epidermis
Serious infectionsOcassionally cutaneous findings are an early feature of serious infections. Usually other systemic findings will aid in early diagnosis.A classic example is meningococcal disease, caused by the bacteria Neisseria meningitidis.This needs early antibiotic treatment. A delay of just hours can be fatal.The hallmark is palpable purpura – due to vasulitis and vascular occlusion and damage.
Other examples of severe cutaneous reactions in infections occur in Kawasaki disease and Staphylococcal Scalded Skin Syndrome.Kawasaki disease is defined by fevers, a widespread exanthem, conjunctivitis, mucositis and lymphadenopathy.Staphylococcal Scalded Skin Syndrome comprises irritability, fevers and widespread erythema developing into blisters and then skin changes like a burn
ErythrodermaThis is erythema involving 90% or more of the body surface area.It often necessitates admission as patients are systemically unwell. Older patients are especially prone to fluid loss, electrolyte imbalance, cardiac failure and hypothermia.The most common causes are psoriasis dermatitis drug reactions pityriasis rubra pilaris lymphomaIn approximately 10%, no cause can be identified.
ConclusionLike all of these modules, this is a very brief introduction to some skin conditions that must be recognized early to minimize patient harm.There are certain dermatological conditions that must be treated early to prevent significnat morbidity or even mortality.