EPONYM. Sweet syndrome

Mercaptopurine-induced Sweet's syndrome

Sweet's syndrome is an acute febrile neutrophilic dermatosis. Drug-induced Sweet's syndrome typically occurs soon after drug administration, with rapid resolution of symptoms with cessation of the offending agent. We report a man in his early 40s who presented with fever and widespread erythematous rash on a background of recently diagnosed mild stricturing ileal Crohn's disease. He was commenced on 6-mercaptopurine 12 days before presentation. Skin biopsy demonstrated diffuse infiltration of neutrophils in the upper dermis, dermal oedema, eosinophils and fibrin deposition. Symptoms rapidly improved with cessation of 6-mercaptopurine without requiring systemic corticosteroids.

Atypical Sweet syndrome: skin sinus tracts in an acutely febrile patient after lymphoma treatment: a case report

Sweet syndrome (SS) is an uncommon inflammatory disease that involves painful skin, edematous, red papules, plaques, or nodules often accompanied by fever and leukocytosis. SS has three subtypes, including classical, malignant-tumor associated, and drug-induced SS (DISS). Patients with DISS have clear histories of recent drug exposure. The incidence of SS is high in hematological malignancy but rare in lymphomas. Glucocorticoid treatment is the recommended treatment for all subtypes of SS. This case study describes a male patient who had a history of sALCL(Systemic anaplastic large cell lymphoma) and was treated with multiple cycles of monoclonal-antibody (mAb) therapy. They also received the G-CSF injection at the site where skin lesions later developed. They met the diagnosis criteria for DISS, which was considered to be caused by the G-CSF injection. In addition, BV(Brentuximab vedotin) administration might predispose them to DISS. This case illustrates the first reported SS during the lymphoma treatment, with rare clinical presentations of local crater-like suppurative skin lesions. This case expands the available literature on SS and hematologic neoplasms and reminds clinicians to promptly recognize and diagnose SS to minimize patient morbidity and long-term sequelae.

Midostaurin-induced Sweet syndrome in a patient with FLT3-ITD-positive AML

Sweet syndrome (SS), also referred as acute febrile neutrophilic dermatosis, is an inflammatory process characterised by the abrupt appearance of erythematous papules or nodules with predominant neutrophilic infiltration in the dermis. Fever and neutrophilia are common presenting features. However, extracellular manifestations, including ocular and musculoskeletal, may occur. SS is divided into three subtypes: classical (or idiopathic), malignancy associated and drug induced. Medication-induced subtype accounts for up to 26% of cases. In recent years, emerging evidence has showed that SS may also occur in neutropenic patients who underwent induction for acute myeloid leukemia (AML). The identification of FMS-like tyrosine kinase 3 (FLT3) gene mutation in approximately 30% of patients with AML has promoted the targeted therapy with FLT3-internal tandem duplication (ITD) inhibitors. Midostaurin, a recently Food and Drug Administration-approved medication for FLT3-ITD-positive AML, was reported once as cause for SS. We report a midostaurin-induced SS with neutropenia in a patient following induction chemotherapy of AML.

Neutrophilic drug reactions

Neutrophilic drug reactions are unique eruptions that can affect hospitalized patients and share a common pathophysiology with neutrophils as the key mediators of inflammation. They range in clinical presentation from papules and plaques to bullae and erosions to pustules. Although there is some overlap in presentation, each has distinguishing features that aid the clinician in differentiation from one another and from other drug hypersensitivity reactions. Much of the data on these reactions are from case reports and series or retrospective review studies. There are limited prospective observational studies dedicated to these adverse drug reactions. We review the more common and life-threatening neutrophilic drug reactions, their proposed mechanism of action, and their management.

Campylobacter gastroenteritis associated with Sweet's syndrome

Sweet's syndrome or acute febrile neutrophilic dermatosis has been associated with underlying infection, malignancy, inflammatory disease and certain medications. The infection agents associated with this include Streptococcus species, Yersinia species, Chlamydia species, Salmonella species and Helicobacter pylori. We report a case of Sweet's syndrome in a 73-year-old woman following a 2 week course of severe gastroenteritis caused by Campylobacter species. Histological examination of skin lesions showed marked inflammatory infiltrate throughout the dermis, composed of neutrophils and histiocytes. The patient was successfully treated with topical and systemic steroids. To date, this is the first case of Sweet's syndrome to be reported linked to Campylobacter species to our knowledge.

Sweet syndrome in children

The objective of this study was to describe the clinical features of Sweet syndrome in children. Our study population consisted of seven children diagnosed with Sweet syndrome over a 22-year period. Age, sex, appearance and location of lesions, associated signs and symptoms, past medical history, pathology, and subsequent disease course were documented for each patient. Fever and typical lesions were reported in most of patients in our study. The majority of patients presented with less-typical findings, such as pustules, vesicles, bullae, oral ulcerations, atrophic scars, and evidence of pathergy. Of the seven children in our study, four were found to have a preceding nonspecific upper respiratory or gastrointestinal infection, and two were diagnosed with an underlying hematologic malignancy. Our results suggest that atypical lesions are relatively common in children with Sweet syndrome and that underlying malignancy is associated with a minority of cases of pediatric Sweet syndrome.

Propylthiouracil-induced anti-neutrophil cytoplasmic antibodies and agranulocytosis together with granulocyte colony-stimulating factor induced Sweet's syndrome in a patient with Graves' disease

Propylthiouracil (PTU) is an antithyroid drug which is known to cause drug-induced vasculitis. PTU is implicated in 80-90% of cases of anti-neutrophil cytoplasm circulating antibody (ANCA)-associated vasculitis caused by anti-thyroid drugs which induce ANCA production. Sweet's syndrome is characterized by fever, leucocytosis, neutrophilia and the sudden onset of painful skin lesions. The pathology of the disease is still unclear. Cytokine dysregulation including interleukin-6 and endogenous granulocyte colony-stimulating factor (G-CSF) are thought to play a role in the pathogenesis of Sweet's syndrome. PTU and G-CSF are known to cause Sweet's syndrome and other neutrophilic dermatosis. The presence of ANCA can have a diagnostic value in Sweet's syndrome. Systemic corticosteroids are the first-line therapy for both diseases. Here we report a female patient with Graves' disease who developed ANCA and Sweet's syndrome after using PTU and G-CSF.