In last week’s Ambulatory Cox’s Conference, Dr. Stephen Philip presented a case of a female with history of rheumatoid arthritis who presented with a chief complaint of fever and rash. Initial laboratory studies unveiled an active urinary sediment concerning for glomerulonephritis. Our expert discussant, Dr. Biff Palmer guided us through the differential diagnosis for fever and rash with renal involvement.
In a patient who presents with fevers and rash, the differential diagnosis is broad and includes infectious, autoimmune, neoplastic, and drug-related etiologies. Our patient had evidence of renal involvement with an active urinary sediment concerning for glomerulonephritis. Our differential diagnosis in this patient included systemic lupus erythematosus, vasculitis (IgA vasculitis, ANCA-associated vasculitis, or cryoglobulinemia), common viral illnesses (EBV, CMV, and HIV), infective endocarditis, disseminated fungal infection, and cutaneous malignancy. The patient underwent a skin biopsy which confirmed the diagnosis of Sweet’s Syndrome.
Sweet’s Syndrome Pearls:
· Also known as acute febrile neutrophilic dermatosis
· Characterized by abrupt onset of painful, erythematous papules, plaques, or nodules which is frequently accompanied by fever and leukocytosis.
· Neutrophilic infiltration to other organ systems can very rarely occur, including ocular, musculoskeletal, central nervous system, cardiovascular system, pulmonary system, gastrointestinal tract/liver, and kidneys. Renal involvement, as in our patient, is rare but commonly presents with proteinuria, less commonly with hematuria or renal insufficiency.1-2
· Most commonly associated with infections (after URI or GI infection), inflammatory bowel disease, pregnancy, autoimmune diseases (RA, SLE, dermatomyositis, sarcoid), malignancies (more commonly hematologic malignancies), and drug related (most common is G-CSF).
· Patients will have abrupt onset of painful inflammatory papules, plaques, or nodules. The distribution will be asymmetric with the upper extremities most commonly effected.
· Often associated with fever, arthralgias, headache, myalgias, and malaise.
· Extracutaneous involvement can occur, frequently ocular and musculoskeletal. However additional organ systems can also become involved.
· Laboratory studies often show a peripheral leukocytosis with neutrophilia. An elevated erythrocyte sedimentation rate and C-reactive protein is common, along with anemia and platelet abnormalities.
· Diagnostic criteria has been established – both major criteria is required along with two of four minor required.3
o Major Criteria:
§ Abrupt onset of painful erythematous plaques or nodules
§ Histopathologic evidence of a dense neutrophilic infiltrate without evidence of leukocytoclastic vasculitis
o Minor Criteria:
§ Fever, > 38 C
§ Association with underlying maligiancy, inflammatory disease, or pregnancy OR preceded by URI, GI infection, or vaccination
§ Excellent response to treatment with systemic glucocorticoids or potassium iodine
§ Abnormal laboratory values at presentation (need 3 of the 4: ESR > 20 mm/hr, positive C-reactive protein, > 8,000 leukocytes, > 70% neutrophils).
· Corticosteroid therapy is first-line. Typically start with prednisone at 0.5 to 1mg/kg per day.
· After initiation of steroid therapy, symptoms are expected to improve within 48 hours.
· Once disease control is obtained, can begin to taper steroids with a plan to discontinue steroids within 4-6 weeks.
· Other therapies such as colchicine, dapsone, and potassium iodide have been used as steroid-sparing agents.4
1. Cohen PR, Kurzrock R. Sweet’s syndrome revisited: a review of disease concepts. Int J Dermatol 2003; 42:761-778.
2. Vignon-Pennanmen MD. The extracutaneous involvement in the neutrophilic dermatoses. Clin Dermatol 2000;18:339–47.
3. von den Driesch P. Sweet’s syndrome (acute febrile neutrophilic dermatosis). J Am Acad Dermatol 1994; 31:535.
4. Cohen PR, Kurzrock R. Sweet’s syndrome: a review of current treatment options. Am J Clin Dermatol 2002; 3:117.