Cellulitis-like Sweet Syndrome with myofasciitis, illustrated through multi-faceted imaging and associated with streptococcal trigger
A 34-year-old woman with a history of uterine leiomyoma presented with fever, myalgia, and an exquisite right thigh pain. The initial diagnosis was presumed cellulitis, and she was treated with broad-spectrum antibiotics. However, further investigations revealed a more complex condition.
Skin biopsy showed extensive interstitial neutrophilia with leukocytoclasia, consistent with giant cellulitis-like Sweet syndrome, a rare variant of Sweet syndrome characterized by larger edematous lesions. This condition typically presents as neutrophilic myositis or myofasciitis, an uncommon manifestation of this systemic inflammatory disorder.
Contrast-enhanced MRI of the right thigh demonstrated geographic intramuscular fluid-attenuation along the fascial plane between the vastus lateralis and vastus intermedius, suspicious for evolving early myonecrosis. Subsequent imaging revealed early myonecrosis in the right thigh, suggesting inflammatory myofasciitis.
Diagnostic features of Sweet syndrome with muscle involvement include the presence of tender, erythematous skin lesions characteristic of Sweet syndrome, muscle involvement demonstrated by imaging modalities such as MRI, histopathology revealing dense neutrophilic infiltration in the dermis and affected muscle tissue without evidence of vasculitis, and elevated inflammatory markers in blood tests.
Treatment approaches for this rare condition predominantly center on systemic corticosteroids, which led to rapid clinical improvement in this case. Immunosuppressive agents such as dapsone, colchicine, or cyclosporine may be used in refractory cases or when corticosteroids are contraindicated. Close monitoring is essential due to the rarity of muscle involvement and to guide tapering therapy.
Despite initial treatment, the woman's condition worsened, leading to concerns about necrotizing soft tissue infection and systemic inflammatory response syndrome. Right thigh fasciotomy was performed, but all tissue samples and cultures were negative for infection. The patient developed hypotension, altered mental status, neutrophilia, rising creatine kinase level, and elevated erythrocyte sedimentation rate, C-reactive protein, and lactate.
Two fasciotomies were performed on hospital day 4, but there was no visible evidence of necrotizing soft tissue infection upon fasciotomy, and tissue cultures were negative. Ultrasound-guided aspiration of knee joint fluid at a later time yielded serous fluid with sparse white blood cells, negative Gram stain, and negative cultures, ruling out septic arthritis.
A recent source emphasizes the role of multimodality imaging (including MRI) in identifying neutrophilic myofasciitis associated with Sweet syndrome, which aids in confirming muscle involvement and ruling out other causes of myositis. Potential triggers of giant cellulitis-like Sweet syndrome include morbid obesity, underlying malignancy, preceding bacteremia, and autoimmune disease.
In conclusion, muscle involvement in Sweet syndrome is rare and manifests as neutrophilic inflammation of muscle and fascia, demonstrated clinically and radiographically. Diagnosis relies on characteristic skin lesions, imaging, and histopathology, while treatment predominantly centers on systemic corticosteroids supplemented by immunosuppressants as needed.
- The woman's condition, despite initially being presumed as cellulitis, evolved into a complex health-and-wellness issue, involving a rare neurological-disorder called Sweet syndrome, which is known to affect skin-care and, in this case, health of the muscles.
- The skin-care manifestations of the Sweet syndrome in this woman were characterized by tender, erythematous skin lesions, while the muscle involvement was demonstrated by imaging modalities such as MRI, revealing inflammatory-therapies and treatments like systemic corticosteroids and immunosuppressive agents as effective treatment approaches.
- Further research in medical-conditions like Sweet syndrome with muscle involvement could benefit from studying potential triggers, such as morbid obesity, malignancies, bacteremia, and autoimmune diseases, to better understand the association between Sweet syndrome and neurological-disorders affecting skin-care and health-and-wellness.
