Life-Threatening Dermatoses - An Overview of Dermatological Emergencies

Introduction:

The life-threatening dermatological conditions are Stevens-Johnson syndrome, Toxic epidermolysis necrolysis syndrome, Kaposi’s varicelliform eruptions, and purpura fulminans that occur acutely and involve other organs of the body. They are usually present without inflammation. Patients have the condition throughout their life carrying the risk of mortality.

What Are Life-Threatening Dermatoses?

Dermatoses are skin conditions causing lesions of irregularity in the skin surface. Dermatoses usually are systematic which means it affects the entire body. They can be associated with medical issues in other organs. The term dermatoses are different from dermatitis. The major difference is that in dermatitis, inflammation of the skin is present, whereas, in dermatoses, the inflammation is absent. Examples of dermatitis are contact dermatitis, seborrheic dermatitis, and atopic dermatitis(eczema). Dermatoses can be infectious or non-infectious. Cutaneous conditions that can become fatal and carry high chances of mortality are called life-threatening dermatoses. Examples of life-threatening dermatoses are Stevens-Johnson syndrome, Toxic epidermal necrolysis syndrome, Kaposi’s varicelliform eruption, and purpura fulminans. A detailed explanation of these four dermatoses is given below.

What Causes Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis Syndrome (TEN)?

Stevens-Johnson syndrome and TEN are similar skin conditions but vary only in the extent of skin surface area which is detached from the underlying tissues. They are acute and rare cutaneous diseases that are serious and cause life-threatening skin lesions. The lesions are reactions to different medications and drugs which lead to the loss of skin and mucous membranes in thin sheets, along with systemic signs and symptoms. The classification according to the affected skin surface area is:

• Stevens-Johnson Syndrome: less than 10 percent of body surface area affected.

• Toxic Epidermal Necrolysis: more than 30 percent of body surface area affected.

• Both Conditions Overlap: when 10 to 30 percent of the body surface is affected.

Etiology:

The main causative agent is medications. Skin reactions are rare and unexpected to occur. The drugs that commonly cause such reactions are:

• Sulfonamides: Sulfasalazine, Cotrimoxazole.

• Antibiotics: Penicillin, Quinolones, and Cephalosporins.

• Non-steroidal anti-inflammatory drugs(NSAIDs).

• Acetaminophen/ Paracetamol.

• Anticonvulsant drugs: carbamazepine, Phenobarbitone, Lamotrigine.

• Nevirapine.

• Allopurinol.

Signs and Symptoms:

The signs and symptoms of the condition start as common symptoms like fever, cough, pain in the eyes, malaise, myalgia(muscle pain), and stuffy nose. The skin lesions present as erythematous, circumscribed, and circular purpuric( bleeding from small blood vessels under the skin) area with a positive Nikolsky sign (on lateral pressure on the skin, the superficial layer sheds). They turn into painful breakouts of skin (erosions) with fluid-filled blisters.

The mucosal lesions are ulcerations and erosions involving the mouth, lips, esophagus, pharynx, eyes, upper respiratory tract, and genitals. The other organ systems affected are the liver, lungs, kidneys, bone marrow, and bone joints.

Diagnosis:

• Skin biopsy shows necrosis of the full thickness of the skin. The direct immunofluorescence test is negative.

• Blood tests show anemia, neutropenia, and eosinophilia.

• The liver function test has elevated levels of transaminases and hypoalbuminemia.

• Other tests like kidney and cardiac function tests also help in diagnosing the condition.

Treatment:

• The treatment involves an integrated professional approach consisting of dermatologists, plastic surgeons, pathologists, ophthalmologists, cardiologists, and other specialists.

• The supportive therapy involves discontinuation of the medications causing the lesions, Fluid replacements with crystalloid, antibiotics in case of secondary infections, nutritional supplement via nasogastric tube, pain management, hospital admission with mechanical ventilation, and sterilized handling of affected skin areas. The lesion would require regular cleaning, application of topical numbing agents, and removal of dead tissues.

What Are Kaposi’s Varicelliform Eruptions?

This condition is also called eczema herpeticum. It is caused due to the spread of a skin infection by a virus to other body parts. It occurs in patients with an underlying skin condition. The virus causes localized fluid-filled small elevations called vesicles on the skin, which spreads and causes Kaposi’s varicelliform eruptions.

Etiology:

• The main etiological agent is herpes simplex virus type 1.

• It is a rare disorder but is potentially dangerous. It mostly occurs in patients with atopic dermatitis. Darier disease, Hailry-Hailey disease, psoriasis, seborrheic dermatitis, etc are other less commonly associated skin diseases.

Pathophysiology:

• The pathogenesis of the disease is poorly understood. The clinical manifestations of the cutaneous condition are the sudden appearance of painful groups of umbilicated (lesions with depressions at centers resembling a navel) fluid-filled skin elevations(vesicles and pustules).

• They progress into crusted, erythematous, and sharply demarcated erosions which later combine and form larger areas of denuded skin. These areas are more prone to get bacterial infections.

• Other systemic symptoms are high fever, malaise, tender and swollen lymph nodes, and involvement of the brain and spinal cord, adrenal glands, lungs, liver, and gastrointestinal tract.

Diagnosis:

• The diagnosis is done through the physical examination of typical skin lesions along with some laboratory tests.

• The most reliable test for identifying the herpes simplex virus is a viral culture of a sample and direct fluorescent antibody staining on a Tzanck smear( staging a thin layer of skin with wright- Giemsa stain).

Treatment:

• Cutaneous disease is managed by antiviral drugs, which can reduce the chances of complications and increase the survival rate.

• The antiviral drug used is nucleoside analogs that act by inhibiting viral DNA replication.

• Acyclovir is the most commonly used drug given as an intravenous drug in high doses. It will resolve the skin lesions in some days.

• Antibiotic prophylaxis can be given to prevent secondary bacterial infection.

How Does Purpura Fulminans Occur?

It is a life-threatening emergency skin condition presenting as purpuric(small blood vessels bleeding underneath the skin)rashes. There is a coagulation of small blood vessels leading to purpuric lesions and necrosis. The condition often demands emergency treatment. The clinical features of the dermatoses are high fever, bleeding from multiple places on the skin, and low blood pressure with disseminated intravascular coagulation(DIC). DIC is a serious condition of overactive proteins that control blood clotting. It forms abnormal blood clots leading to reduced blood volume for circulation and collapse. It can occur in adults, children, and newborns. The mortality rate has been decreasing with supportive care, improved management of secondary complications, and some targeted treatments, but it remains a disabling condition often resulting in major amputations in those who survive.

Etiology:

• It is a disruption of the clotting mechanism of cutaneous microvasculature and hemorrhagic necrosis( bleeding leading to the death of tissue). There are three types of purpura fulminans.

• Neonatal Purpura Fulminans - It is a genetic deficiency of anticoagulants protein C, S, and antithrombin Ⅲ.

• Idiopathic Purpura Fulminans - It is an autoimmune condition caused by an infection.

• Acute Infectious Purpura Fulminans - It is the most common form found in patients with sepsis and necrotizing fasciitis.

Diagnosis:

• Blood Tests: Levels of anticoagulant proteins like antithrombin Ⅲ, proteins C and S are evaluated.

• Raised coagulation factors ( prothrombin, Partial thromboplastin time), increased degradation products of serum fibrin, and a decreased fibrinogen are other confirmatory tests for the disease.

Treatment:

• Supportive care and sufficient hydration are the main treatment approaches. To resolve the problem with coagulation, anticoagulation therapy is commenced.

• Replacement with blood, protein factors, and platelets are required. To decrease the mortality, the affected and dead tissue is removed.

• The treatment for neonatal type is platelet transfusion, protein C and S levels assessment, and hydration, followed by fresh frozen plasma transfusion. Anticoagulants used are Heparin and Warfarin.

• The treatment for the idiopathic type is similar to the neonatal form, but corticosteroids will be given additionally for immunomodulation. In acute infectious types, broad-spectrum antibiotics are used.

• Clindamycin, Carbapenems, Vancomycin along with beta lactam-beta lactamase inhibitors are used.

• Repeated surgical removal of dead tissues will be required in all three types of purpura fulminans.

Conclusion:

Even though the skin conditions are life-threatening, they can be efficiently managed with the help of a multidisciplinary team consisting of a dermatologist, ophthalmologist, pathologist, nephrologist, plastic surgeon, gastroenterologist, and nurses. The patients require regular follow-ups with their physicians to monitor the proper functioning of other organ systems.