From the Guidelines
Laboratory tests for someone with Stevens-Johnson Syndrome (SJS) should include a complete blood count (CBC) with differential, liver function tests, and kidney function tests, as well as consideration of a skin biopsy to assess for full-thickness epidermal necrosis, as recommended by the most recent guidelines 1. When evaluating a patient with suspected SJS, it is crucial to rule out other etiologies of the skin problem, such as infections or other drug reactions, and to assess for associated nephritis with a urinalysis (UA) if necessary 1. Some key laboratory tests to consider include:
- Complete blood count (CBC) with differential to assess for signs of infection or inflammation
- Liver function tests, including ALT, AST, and bilirubin, to evaluate liver involvement
- Kidney function tests, including BUN and creatinine, to assess renal function
- Blood cultures if infection is suspected
- Skin biopsy to confirm the diagnosis histologically and to assess for full-thickness epidermal necrosis
- Urinalysis to monitor kidney function and detect potential complications Regular monitoring of these parameters is essential, as SJS can rapidly progress and affect multiple organ systems, and early detection of abnormalities allows for prompt intervention to prevent further complications 1.
From the Research
Laboratory Findings in Stevens-Johnson Syndrome
- There are no specific laboratory tests to diagnose Stevens-Johnson syndrome (SJS), but various tests can help support the diagnosis and monitor the patient's condition 2, 3.
- Laboratory findings may include:
- Elevated white blood cell count
- Elevated erythrocyte sedimentation rate (ESR)
- Elevated C-reactive protein (CRP)
- Abnormal liver function tests
- Abnormal renal function tests
- Biopsy of the affected skin can help confirm the diagnosis of SJS 3.
Systemic Involvement
- SJS can involve various organs, including the skin, mucous membranes, eyes, and respiratory tract 4, 3.
- Laboratory tests can help monitor the involvement of these organs, such as:
- Complete blood count (CBC) to monitor for anemia, leukocytosis, or thrombocytopenia
- Blood chemistry tests to monitor for electrolyte imbalances or organ dysfunction
- Urinalysis to monitor for renal involvement
Immunological Findings
- SJS is an immunologically mediated condition, and laboratory tests can help identify the underlying immune response 4, 5.
- Tests may include:
- Human leukocyte antigen (HLA) typing to identify genetic predisposition to SJS
- Measurement of cytokine levels, such as tumor necrosis factor-alpha (TNF-alpha)
- Measurement of immune cell subsets, such as CD4+ and CD8+ T cells