D.R.E.S.S Awareness
D.R.E.S.S stands for Drug Reaction with Eosinophilia and Systemic Symptoms. It is sometimes referred to as DIHS (Drug Induced Hypersensitivity Syndrome). D.R.E.S.S. is one of several severe adverse drug reactions that can occur from taking one of over 50 prescription drugs. It is an extremely dangerous condition that requires prompt diagnosis and careful monitoring.
This type of allergic reaction is unique in that the first symptoms are delayed, usually appearing after two weeks or more of starting a medication. Even more complicating is that DRESS is a progressive condition where some of the most serious symptoms can occur long after the offending drug has been stopped. DRESS is also frequently associated with a viral infection or reactivation called HHV-6. Patients reactivating with this virus typically have a more severe course of DRESS and require additional treatment.
The first signs of DRESS are usually a fever and then rash. If you are taking medication and present with these symptoms, seek medical attention promptly and insist that DRESS be considered! Many physicians haven not treated a DRESS patient and may not suspect it. While currently thought of as a "rare" disease, it is underdiagnosed and underreported, so may be more prevalent than once thought.
Symptoms of DRESS can progress to severe organ involvement affecting most often the liver, kidneys, lungs and heart. Again, these symptoms can present long after the first signs of DRESS and need to be monitored for many months.
No one, unfortunately, is guaranteed immunity from DRESS. It's a fairly unpredictable condition that can affect anyone who takes a prescription drug. What we can do is be aware of the top offending drugs and be aware of the symptoms.
A genetic association has been determined between certain HLA's (human leukocyte antigen) and certain drugs that can cause drug hypersensitivity. Current studies are being conducted to further along this research and hopefully identify more relationships between our genes and drugs.
Diagnosing DRESS can be elusive because it relies on a series of conditions and not just one lab test. Thankfully, researchers have developed a method in which to determine if DRESS should be considered or confirmed.
The first step in controlling DRESS is to identify and stop taking the drug causing it. The next step is extreme diligence in monitoring any ongoing symptoms. It is essential to find a medical team who can accommodate this.
WHO IS AT RISK?
Anyone, at any age, that takes any medication is susceptible to DRESS. There are currently over 50 known drugs that have caused DRESS, and the list is growing. Recently, a genetic predisposition to DRESS has been identified for certain drugs, specifically, allopurinol and abacavir and nevirapine. More research needs to be done to identify other gene to drug relationships. While poorly reported, DRESS is estimated to occur between 1 in 1,000 and 1 in 10,000 drug exposures with a mortality rate of 10 to 20%.
WHAT CAUSES THE DISEASE?
Advances are underway in understanding the complexity of how DRESS Syndrome occurs. We do know there are three common factors; genetic predisposition, defect in drug metabolization and a triggering factor mostly a viral infection.
SYMPTOMS
First signs of DRESS are delayed, starting typically two weeks or later after drug initiation. Because it is a progressive condition, symptoms appear through the course of the illness and not always at once. •Fever •Rash usually starting on upper trunk or face •Edema (swelling of face and body) •Multi-systemic involvement, very often includes the liver and also can affect kidneys, lungs and heart and other organs and the thyroid. •Pharyngitis (sore throat) •Exfoliative dermatitis (peeling off of skin) CLINICAL AND LABORATORY FINDINGS Blood abnormalities occurring at various points in the course of illness may include atypical lymphocytes and eosinophilia. Also elevated liver enzymes, lymphopenia and hemophagocytic syndrome. HHV-6 viral reactivation, when properly tested, may be found in the blood usually two weeks after onset of symptoms.
HHV-6 VIRAL IMPLICATION
Human herpesvirus 6 has been shown to play an important role in DRESS. This virus, which lays dormant in almost everyone, has been demonstrated to reactivate in over 50% of DRESS patients. Those with viral reactivation tend to have a more severe illness with a longer and more complicated course including organ failure.
DIAGNOSIS AND TREATMENT
Most important is identifying and discontinuing the offending drug. However, DRESS is tricky in that it can continue to get worse even after stopping the drug. It is imperative to diagnose DRESS quickly and follow up with proper testing. Due to the progressive nature of the illness, certain conditions like eosinophilia and HHV-6 reactivation may not show up initially in blood test. Retesting for these at the right time could make a significant difference in diagnosis and treatment. Well-defined criteria has been developed to aid in a scoring system for diagnosis. Treatment will vary based on confirmation of symptoms but may include oral steroids, IVIG and antivirals.
COMPLICATIONS
Seemingly successful, initial treatment of symptoms are not necessarily an indication that the patient is home free. Many complications of DRESS can develop later, including: •Dangerous flares during steroid taper •Myocarditis •Autoimmune disorders: Type 1 diabetes and thyroiditis
DRUGS THAT CAN CAUSE DRESS
Anticonvulsants: phenytoin, carbamazepine, phenobarbital Antibiotics: minocycline,sulfamethoxazole and trimethoprim (bactrim) linezolid,doxycycline Antidepressants: desipramine,amitriptyline Antivirals: abacavir, telaprevir, zalciabine ACE inhibitors: enalapril Beta blockers: atenolol Sulfasalazine NSAIDS Also: lamotrigine, allopurinal, modafinil,dapsone,vancomycin, olanzapine, nevirapine, ranitidine, azathioprine, dobutamine,pyrazinamide. (List is not complete.)