DRESS Syndrome Flashcards
DRESS Syndrome
DRESS syndrome = Drug Reaction with Eosinophilia and Systemic Symptoms
DRESS is an unexpected, severe reaction to medication. Several organs are commonly affected including the skin, liver, kidneys, lungs and heart. Not all of these organs may be affected at any one time.
DRESS Syndrome - Features
Classically patients develop a morbilliform skin rash in 80% cases which often leads to an exfoliative dermatitis, high fever, and inflammation of one or more organs. Vesicles and bullae may be seen. Erythroderma can occur in 10% of cases, mucosal involvement in 25% and facial swelling in 30%. The reaction usually occurs 2-8 weeks after commencing the offending drug.
Patients may develop systematic symptoms which can include haematological abnormalities (raised and low white count, eosinophilia (in 30% this is > 2.0 * 109 /L, thrombocytopaenia, anaemia, atypical lymphocytes), enlarged lymph nodes (75%), 10% develop kidney disease which is usually mild (interstitial nephritis is common, renal failure is rare), myocarditis, pericarditis, liver enlargement, hepatitis and rarely hepatic necrosis with liver failure (abnormal liver function tests are found in 70-90% in particularly raised transaminases), lung disease (pneumonitis, pleuritis, pneumonia), neurological involvement which may lead to meningitis and encephalitis, gastrointestinal symptoms, in severe cases, acute colitis and pancreatitis can occur, and endocrine abnormalities may include thyroiditis and diabetes.
DRESS Syndrome - Diagnosis
Diagnosis can be very difficult and it may also be difficult to determine the exact drug causing the hypersensitivity as first exposure may have started 8 weeks prior. Common drugs causing DRESS include allopurinol, anti-epileptics, antibiotics, immunosuppresants, HIV treatment and NSAIDS. A careful drug history should be taken.
The diagnosis should be suspected when there is presence of the triad of extensive skin rash, high fever, and organ involvement, supported by a finding of eosinophilia and abnormal liver function tests. RegiSCAR has proposed a diagnostic criteria and patients require at least 3 of the following:
Hospitalisation
Reaction suspected to be drug related
Acute skin rash
Fever about 38ºC
Enlarged lymph nodes at two sites
Involvement of at least one internal organ
Blood count abnormalities such as low platelets, raised eosinophils or abnormal lymphocyte count.
Skin biopsy can help to confirm the diagnosis. This may show inflammatory infiltrate in particularly eosinophils, extravasated erythrocytes and oedema. Regular blood tests including FBC, clotting, liver and renal function, CK, viral screen, glucose and thyroid function tests should be taken. Investigations looking for complications should be undertaken including ECG, CXR, echocardiogram, and urinalysis.
DRESS Syndrome - Mx
DRESS syndrome treatment requires all medications that are a possible culprits to be stopped and supportive care started. Antihistamines, topical steroids and emollients can be used to help control the rash. Careful fluid balance is necessary and clinicians should be aware of the patients nutritional status. Skin should be regularly checked and secondary infections should be treated with antibiotics. Systemic steroids may be started in severe cases where exfoliative dermatitis / pneumonitis / hepatitis is present. Occasionally immunosuppressants, intravenous immunoglobulin and plasmapheresis may be started. Potential culprit drugs should not be restarted again. The mortality is around 8%.
DRESS Syndrome - Diagnosis: Example Question
A 72-year-old lady is admitted with a tonic-clonic seizure. She was initially treated with two doses of 10mg diazepam however she failed to respond. She was then prescribed a loading dose of intravenous phenytoin and then prescribed maintenance dose phenytoin. Past medical history included a previous stroke, gallstones and hypertension. Drug history included clopidogrel, amlodipine, simvastatin. She recovered well and was discharged 6 days later.
Three weeks after her hospital admission she visits her GP accompanied by her husband complaining of feeling generally unwell and a rash. On examination she has a wide spread morbilliform eruption on most of her body and some mild right upper quadrant pain. The GP could palpate cervical and inguinal lymph nodes. Observations heart rate 110 regular, blood pressure 120/80, saturations 97% on air and temperature 38.2. The GP sends the patient to hospital for further tests. Bloods show:
Hb 110 g/l WCC 14 * 109/l Neutrophils 7.2 * 109/l Eosinophils 2.3 * 109/l Platelets 81 * 109/l Na+ 141 mmol/l K+ 4.3 mmol/l Creatinine 101 µmol/l Urea 6.8 mmol/l Bilirubin 22 µmol/l Alk phos 80 u/l ALT 150 u/l Albumin 32 g/l INR 1.1
What is the most likely diagnosis?
Lymphoma > DRESS syndrome Cholecystitis EBV Meningococcal septicaemia
This patient has DRESS syndrome (drug reaction with eosinophilia and systemic symptoms) after starting phenytoin.
DRESS Syndrome - Rash and Drug Precipitants
Moniliform Rash
The term morbilliform refers to a rash that looks like measles. The rash consists of macular lesions that are red and usually 2–10 mm in diameter but may be confluent in places.
Drugs causing DRESS Abx Anti-Epileptics NSAIDSs Allopurinol HIV treatment Immunosuppressants
