After initial clinical evaluation, a patient presenting with sudden, painful erythematous lesions on the face and neck was urgently referred to the dermatology department. Upon consultation, the medical team opted to discontinue the patient’s recently prescribed medication. A comprehensive diagnostic workup was initiated, including a skin biopsy, a complete blood count, and laboratory testing for antibodies, lupus anticoagulant, and various serology markers. To manage symptoms, the patient began a regimen of oral corticosteroids.
Within 48 hours of treatment, the intensity of the skin lesions diminished noticeably and the associated pain subsided. Laboratory results confirmed the presence of leukocytosis accompanied by neutrophilia, as well as the presence of antibodies and lupus anticoagulant, while routine serology tests yielded negative results. Twenty days later, the pathology report from the skin biopsy confirmed a diagnosis of Sweet syndrome.
Sweet syndrome, medically known as acute febrile neutrophilic dermatosis, is a rare dermatological condition categorized among the neutrophilic dermatoses. It is defined histopathologically by the presence of dense neutrophil infiltrates within the tissue. Clinically, the syndrome manifests as the sudden appearance of painful, erythematous papules or plaques. These lesions typically appear asymmetrically on the face, neck, upper trunk, and hands. The condition is often accompanied by systemic symptoms, including fever and significant leukocytosis with neutrophilia.
The precise etiology of Sweet syndrome remains uncertain, though current research suggests the pathogenesis is driven by cytokines that facilitate the chemotaxis and activation of neutrophils and histiocytes. It is widely believed to be an immune-mediated hypersensitivity reaction triggered by antecedent factors, such as upper respiratory tract infections, paraneoplastic processes, or the introduction of certain pharmaceutical agents. Accurate diagnosis is essential because the condition requires the exclusion of underlying systemic illnesses, such as occult malignancies, which may manifest as atypical skin lesions on the back of the hands.
While the syndrome can be idiopathic, drug-induced cases are more common in women. Medications frequently associated with the development of Sweet syndrome include contraceptives, antiepileptics, antibiotics, antihypertensives, vaccines, and colony-stimulating factors. However, as this case highlights, other medications may potentially act as triggers.
The gold standard for initial treatment is the administration of oral corticosteroids. Patients typically show a rapid response, with systemic discomfort and pain subsiding within the first few hours of therapy and skin lesions clearing in less than a week. In this instance, the sudden emergence of lesions required a rigorous differential diagnosis to rule out conditions such as urticaria, contact dermatitis, toxicoderma, and cutaneous lupus. The integration of clinical history, laboratory findings, and the conclusive histopathological results from the biopsy allowed the medical team to reach a definitive diagnosis of Sweet syndrome, ensuring the patient received the correct targeted treatment.
