Acute febrile neutrophilic dermatosis in Adult
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Synopsis
Sweet syndrome is classified by etiology:
- Classic idiopathic
- Pregnancy-associated
- Parainflammatory
- Paraneoplastic
- Drug-associated
- Classic (includes all inflammatory causes including infection, inflammatory bowel disease [IBD], and pregnancy)
- Paraneoplastic and drug-related
Although the exact etiology is still unclear, abnormal cytokine expression and atypical neutrophil function are thought to contribute to the pathogenesis. A genetic predisposition may also contribute.
Pathergy is reported in a minority of adult cases. When present, lesions arise or worsen in sites of cutaneous injury, such as needle sticks. Extracutaneous manifestations such as fever, headaches, myalgias, malaise, arthralgias, and ocular inflammation may be seen. Other sites that may rarely be affected include the oral mucosa, liver (hepatitis), kidney (acute renal failure), lungs (pulmonary abscess and infiltrate), heart (pericarditis, aortitis), central nervous system (CNS) (encephalitis), gastrointestinal (GI) tract (ileitis), lymphatics (lymphadenitis), musculoskeletal (myositis), and bones (sterile osteomyelitis). Hypotension and tachycardia are rare but can occur as a result of systemic inflammation.
Neutrophilic dermatosis of the dorsal hands is considered by many to represent a localized form of Sweet syndrome. Hematologic malignancies and IBD are the most common associations with this subtype.
Necrotizing neutrophilic dermatosis describes a subset of patients with severe Sweet syndrome or pyoderma gangrenosum who develop, in addition to their cutaneous disease, fever, leukocytosis (or a leukemoid reaction), and features of shock. Skin pain is a prominent symptom. Additionally, soft tissues underlying areas of skin involvement may be affected with neutrophilic infiltrates and necrosis.
Sweet syndrome typically responds rapidly to systemic corticosteroids, but recurrences can be seen in up to a third of affected individuals.
Codes
ICD10CM:L98.2 – Febrile neutrophilic dermatosis [Sweet]
SNOMEDCT:
84625002 – Acute febrile neutrophilic dermatosis
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Diagnostic Pearls
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Differential Diagnosis & Pitfalls
- Pyoderma gangrenosum – Begins as a pustule and evolves into a purulent ulcer with rolled borders. Has similar associations, including IBD and malignancy.
- Neutrophilic eccrine hidradenitis – Drug-induced toxicity of the eccrine coils 1-2 weeks following chemotherapy. Palmar involvement is more suggestive of this diagnosis. Patients typically lack fevers, but pathology may be required to differentiate these entities.
- Rheumatoid neutrophilic dermatosis
- Bowel-associated dermatosis-arthritis syndrome – Pustular skin lesions and aseptic arthritis in bowel-bypass patients.
- Wells syndrome – Involved skin is typically neither tender nor warm. Eosinophilia is present in 50% of affected individuals; neutrophilia would be unusual. Eosinophils and flame figures can be seen on pathology.
- Necrotizing fasciitis – Necrotizing neutrophilic dermatosis may mimic necrotizing fasciitis. Histopathologic findings and blood and tissue cultures are useful diagnostically.
- Erythema multiforme – Should display classic target lesions with 3 zones of color; favors acral surfaces. Oral involvement is common.
- Azathioprine hypersensitivity syndrome – Acute neutrophilic and systemic reaction after initiating azathioprine. See drug-induced hypersensitivity syndrome.
- Urticarial vasculitis
- Erythema elevatum diutinum – A form of chronic necrotizing vasculitis that primarily involves extensor surfaces.
- Cutaneous small vessel vasculitis – Presents symmetrically on the lower extremities; typically smaller than the plaques of Sweet syndrome.
- Behçet disease – Rare, recurrent, and associated with oral or genital ulcers.
- Bromoderma or iododerma
- Bacterial infections (furunculosis, cellulitis)
- Sporotrichosis
- Mycobacteria spp infections (typical and atypical), including Mycobacterium marinum
- Erythema nodosum – Primarily over the shins.
- Leishmaniasis (New World and Old World) – Recent travel to endemic areas.
- Lymphoma / leukemia cutis
- Metastatic carcinoma
- Majocchi granuloma
- Sarcoidosis
- Orf
- Cat-scratch disease
- Cutaneous anthrax
- Coccidioidomycosis
- VEXAS syndrome
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Management Pearls
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Therapy
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Drug Reaction Data
Below is a list of drugs with literature evidence indicating an adverse association with this diagnosis. The list is continually updated through ongoing research and new medication approvals. Click on Citations to sort by number of citations or click on Medication to sort the medications alphabetically.Subscription Required
References
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Last Reviewed:12/05/2022
Last Updated:02/09/2023
Last Updated:02/09/2023
Acute febrile neutrophilic dermatosis in Adult
See also in: Cellulitis DDx