Common Drug Allergy May Lead To Serious SJS Or TEN
Toxic epidermal necrolysis (TEN) is a rare disorder usually caused by a drug allergy, though it has been known to result from viruses, immunizations, or bone marrow transplants. When it occurs, it can be very painful, with the incidence of death around 5% of the .4 to 1.2 cases reported each year. Medical opinion agrees that TEN is a more severe form of Stevens Johnson Syndrome (SJS ). However, there is controversy over whether it is also a form of erythema multiforme, which is clinically distinct as it is caused more often by a virus with different symptoms. TEN, by contrast, is quite severe. Keratinocytes, which form the durable protein keratin, which in turn holds the epidermis and dermis together, are affected when the body has difficulty metabolizing certain drugs. These are drugs prescribed for pain, infection, or to control convulsions. Popular brand names are among these, as well as the ubiquitous acetaminophen. The popular media outlet WebMD reports history of medication use in over 95% of cases. The more pronounced symptom of rash can often be preceded by 1 to 2 weeks of intense fever or symptoms resembling an upper respiratory infection. TEN can most severely affect more vulnerable parts of the body’s epithelial covering - mucous membrane tissue such as the mouth, nose, eyes, and vagina. When this occurs, it can disrupt eating and vision, calling for special precautions and therapies, like feeding with a nasogastric tube. It is important to confirm diagnosis in order to evaluate treatment options. When TEN occurs, the patient is immediately hospitalized at a burn unit, if available, or intensive care unit. Early treatment includes: • Stopping the medication causing allergic reaction
• IV drip for hydration and electrolyte fluids
• Debridement, or removal of dead cells
• Protective bandages and controlled environment to prevent infection
• Preventive antibiotics
• Treatment of complications A second, very promising line of treatment is IVIG, or intravenous immunoglobulin, followed by the sometimes applicable third option of drugs like cyclosporin. TEN is much less common in children. In fact, it appears more often in the elderly because they are more likely to take drugs that cause the allergic reaction. A biopsy can distinguish TEN from staphylococcal scalded skin, more often found in children. There are differences in the histological components that can be detected under a microscope. Scalded skin syndrome is the name for a range of blistering skin disorders causing blistering similar in appearance to TEN. This syndrome is caused by toxins in some strains of Staphylococcus bacteria. After an erythematous cellulitis (inflammation and reddening of the cells) there is an acute exfoliation of the epidermis. It is known more specifically in newborns as Ritter von Ritterschein disease. The severity and treatment of these and other life threatening skin rashes can vary. More problematic are the complications that arise because the protective, cutaneous layer is compromised or, in worst cases, destroyed. You will find more information about the overlap of this and less severe disorders in our other articles pertaining to SJS .
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