Recent Advances in Drug-Induced Hypersensitivity Syndrome/Drug Reaction with Eosinophilia and Systemic Symptoms

Table 1

(a) Diagnostic criteria for drug reaction with eosinophilia and systemic symptoms (DRESS) [2].

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Diagnosis of DRESS is confirmed by the presence of all of the following criteria:

(1) Cutaneous drug eruption

(2) Adenopathies ≥ 2 cm in diameter or hepatitis (liver transaminases ≥ 2 times upper limit of normal) or interstitial nephritis or interstitial pneumonitis or carditis

(3) Hematologic abnormalities: eosinophilia ≥ 1.5 × 10⁹ L⁻¹ or atypical lymphocytes

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(b) Criteria for potential cases of drug reaction with DRESS by RegiSCAR [7].

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(1) Hospitalization

(2) Reaction suspected to be drug-related

(3) Acute skin rash

(4) Fever above 38°C

(5) Enlarged lymph nodes in at least two sites

(6) Involvement of at least one internal organ

(7) Blood count abnormalities

 (i) Lymphocytes above or below the laboratory limits

 (ii) Eosinophils above the laboratory limits

 (iii) Platelets below the laboratory limits

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Three or more criteria required. RegiSCAR: research group investigating severe cutaneous adverse reactions (SCAR) [7].

(c) Diagnostic criteria for drug-induced hypersensitivity syndrome (DIHS) established by a Japanese consensus group [3].

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(1) Maculopapular rash developing 3 weeks after starting with a limited number of drugs

(2) Prolonged clinical symptoms 2 weeks after discontinuation of the causative drug

(3) Fever (≥38°C)

(4) Liver abnormalities (alanine aminotransferase ≥ 100 U·L⁻¹)^a

(5) Leukocyte abnormalities (at least one present)

 (a) Leukocytosis (≥11 × 10⁹ L⁻¹)

 (b) Atypical lymphocytosis (≥5%)

 (c) Eosinophilia (≥1.5 × 10⁹ L⁻¹)

(6) Lymphadenopathy

(7) Human herpesvirus 6 reactivation

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The diagnosis is confirmed by the presence of the seven criteria above (typical DIHS) or of the first five (1–5) criteria (atypical DIHS). ^aThis can be replaced by other organ involvement, such as renal involvement.