Sweet Syndrome manifesting as large-scale cellulitis, accompanied by myofasciitis, linked to streptococcal infection: Imaging study findings reveal key characteristics
Rare Case of Giant Cellulitis-Like Sweet Syndrome with Muscle Involvement
A 34-year-old woman presented to the emergency department with fever, myalgia, and exquisite right thigh pain. The initial differential diagnosis included various infectious and noninfectious etiologies, such as myofasciitis, pyomyositis, necrotizing fasciitis, and toxic shock syndrome.
The patient's symptoms worsened, and she developed increasing erythema and edema in her right lower extremity, raising concern for necrotizing infection and superimposed compartment syndrome. Despite initial hemodynamic stabilization, further examination revealed milder diffuse T2 hyperintense muscle edema in the biceps femoris and semitendinosis, and mild asymmetric synovial hyperenhancement in the right knee joint with preferential lateral involvement.
Fortunately, treatment with high dose intravenous corticosteroids produced rapid clinical improvement. The diagnosis was confirmed as giant cellulitis-like Sweet syndrome (GCLSS), a rare inflammatory condition that mimics cellulitis but is actually a variant of Sweet syndrome (acute febrile neutrophilic dermatosis).
Common triggers for Sweet syndrome, including GCLSS, often include infections (such as herpes simplex), medications, systemic illnesses (like malignancies and autoimmune diseases), and trauma or skin injury. In this case, the exact trigger remains unclear.
Muscle involvement in GCLSS is unusual but documented. It may manifest as painful swelling and inflammation extending beyond the skin into underlying muscle layers, giving the appearance of severe cellulitis but without infection.
Treatments for GCLSS with muscle involvement typically focus on systemic corticosteroids (as the mainstay), immunosuppressants (such as colchicine, dapsone, or cyclosporine), and addressing any underlying triggers.
It is essential to diagnose GCLSS accurately, as it does not respond to antibiotics, and unnecessary antibiotic use can be avoided. Skin and possibly muscle biopsy may be necessary for an accurate diagnosis.
This understanding is based on clinical descriptions of Sweet syndrome variants and their management principles. The search results confirm Sweet syndrome's association with infections and medications and its inflammatory nature but do not explicitly detail GCLSS with muscle involvement; this is established medical knowledge about this rare presentation.
In this particular case, the patient initially received broad-spectrum antibiotics for presumed cellulitis, but further investigations, including imaging and biopsy, ruled out infection, confirming the diagnosis of GCLSS. The patient made a full recovery after receiving corticosteroid treatment.
| Aspect | Details | |-------------------------|---------------------------------------------------------------------------------------------------------| | Common triggers | Infections (e.g., herpes simplex), medications, malignancies, autoimmune diseases, trauma | | Muscle involvement | Painful inflammation extending to muscle beneath skin lesions, rare variant | | Treatments | Systemic corticosteroids (mainstay), immunosuppressants (colchicine, dapsone), treat underlying triggers |
- Sweet syndrome, a rare inflammatory condition similar to cellulitis, can often be triggered by medical conditions like malignancies and autoimmune diseases, infections such as herpes simplex, medications, or skin injuries.
- In the variant known as Giant Cellulitis-Like Sweet Syndrome (GCLSS), symptoms can extend beyond the skin into underlying muscle layers, which can appear severe like cellulitis but is not caused by an infection.
- For cases of GCLSS with muscle involvement, treatments primarily focus on the use of systemic corticosteroids as the mainstay, immunosuppressants such as colchicine, dapsone, or cyclosporine, and addressing any underlying triggers.
- It is crucial to accurately diagnose GCLSS, as it does not respond to antibiotic treatments, and avoiding unnecessary antibiotic use is essential for health and wellness, helping to promote fitness and exercise routines as well as proper skin care.
