top of page
Diagnosis and Treatment


D.R.E.S.S. syndrome is a challenging diagnosis as it is an uncommon condition that occurs progressively, involves many clinical symptoms including fever, rash, facial swelling, enlarged lymph nodes and organ injury, and requires a number of diagnostic tests. Because it can affect multiple organs and present with a number of lab abnormalities, physicians must rule out other diseases and types of drug reactions and have a high level of suspicion for DRESS.

Many DRESS patients will have an abnormal level of blood cells called eosinophils show up in their blood tests. Eosinophils are associated with allergic diseases and, in abundance, can wreak havoc on organs. However, while it’s in the name of this condition, these eosinophils are not always evident in the blood. Sometimes, another type of white blood cell, atypical lymphocytes, may show up in lieu of or in addition to eosinophils.

While there currently is not a 100% definitive test for diagnosing DRESS, international experts have developed tools that have become best practice to help physicians confirm or exclude the diagnosis.

Evaluation of signs, symptoms, medical history and laboratory findings are all part of the work-up. If DRESS is suspected, the following labs in addition to referring to the scoring chart can help aid your physician in making a proper diagnosis. 


The Registry of Severe Cutaneous Adverse Reactions (RegiSCAR), the Japanese Consensus Group (J-SCAR) and Boquet et al# are all scoring systems which use a set of defined criteria to make the determination of DRESS.

By comparison, the J-SCAR includes the detection of HHV-6 viral reactivation. If present, the Japanese refer to the condition as DIHS (Drug-induced hypersensitivity syndrome).

It’s important to note that while these tools are helpful, some of the scoring criteria are for symptoms that may occur later in the disease or may be transient and not detectable at the time of diagnostic testing. The golden rule should be to assume DRESS in a patient who’s taken medication and presents with; fever, rash, facial edema/swelling and enlarged lymph nodes.














(DRESS syndrome: Descamps/Ranger-Rogez)


Complete blood count w/differential and peripheral blood smear (CBC)

  • Eosinophilia (>700micorL),

  • Lymphocytosis (absolute lymphocyte count >4500/microL), and/or

  • Atypical lymphocytes on peripheral smear


Liver function tests (LFT)

  • Elevated enzymes 1.5 to 2 times the normal value

  • ALT (serum alanine aminotransferase)

  • AST (aspartate transaminase)

  • ALP (alkaline phosphate)

  • Bilirubin

  • Gamma-glutamyl transferase


Serum creatinine and urinalysis

  • Moderate elevation in creatinine level

  • Low grade proteinuria

  • Indications of kidney involvement: abnormal urinary sediment w/ occasional eosinophils


Serology for viral hepatitis

  • Hepatitis A IgM antibody

  • Hepatitis B surface antigen

  • Hepatitis B core IgM antibody

  • Hepatitis C viral RNA


Tests for herpes viral infection
Active or reactivated virus: human herpes virus-6 (HHV-6), human herpes virus-7 (HHV-7), Epstein-Barr virus (EBV), and cytomegalovirus (CMV) using quantitative polymerase chain reaction (qPCR) on serum or plasma. Test upon admission and again in two to three weeks as the viral load detection in blood has a latency of this time period.

HHV-6 is known to preferentially reactivate in DRESS as opposed to other severe drug reactions and could be an important clue in diagnosis. Patients with viral reactivation tend to have a more severe and prolonged course of illness. Detailed viral testing information can be found here:

  • Electrolytes in blood and urine

  • Serum creatine phosphokinase and troponin

  • Serum lactic dehydrogenase, ferritin, and triglycerides

  • Serum calcium and procalcitonin

  • Serum glucose

  • Prothrombin time and activated partial thromboplastin time

  • Serum lipase

  • Serum protein electrophoresis

  • Antinuclear antibodies, blood cultures (to rule out other diagnoses)


Skin Biopsy
Findings that may support diagnosis

  • Mild spongiosis

  • Infiltrate of atypical lymphocytes

  • Increased eosinophils

  • Dermal edema


Genetic Testing

In cases where a drug and genetic association is known, such as Vancomycin, genetic testing for the HLA markers specific to that drug may help aid in diagnosis.


The first order of action with DRESS is to identify and stop the offending medication.


Treatments of DRESS Syndrome will vary by case, taking into consideration severity, other existing medical conditions and the presence of viral reactivation. 

The mainstay treatment is systemic corticosteroids and oral prednisone. They may be indicated when organs are affected and could decrease the chance of symptom flare-ups and also autoimmune complications. Steroids are typically started as high dose and weaned very slowly to reduce the chance of disease reoccurrence. Patients who have a difficult time weaning from steroids without a flare in symptoms may put on additional, supportive medications. 

Other treatments include; cyclosporin, intravenous immunoglobulin (IVIG), mycophenolate mofetil (Cellcept) and rituximab. Antiviral medications, like ganciclovir may indicated along with systemic steroids or IVIG in those patients who have severe viral reactivation. 

Prognosis and Long-Term Complications >

bottom of page