Sweet syndrome induced by FLT3 inhibitors: case report and literature review.

BACKGROUND: Acute febrile neutrophilic dermatosis, also commonly referred to as Sweet syndrome, is often associated with tumors, infections, immune disorders and medications. FLT3 inhibitor-induced Sweet syndrome is a rare complication. METHODS AND RESULTS: We report a patient with relapsed and refractory acute monocytic leukemia harboring high-frequency FLT3-ITD and DNMT3a mutations. The FLT3 inhibitor gilteritinib was administered for reinduction therapy after failure of chemotherapy with a combination of venetoclax, decitabine, aclarubicin, cytarabine and granulocyte colony-stimulating factor. The leukemia patient achieved remission after 1 month of treatment. However, Sweet syndrome induced by gilteritinib, which was confirmed by skin biopsy, developed during induction therapy. Similar cases of Sweet syndrome following FLT3 inhibitor therapy for acute myeloid leukemia were reviewed. CONCLUSION: Attention should be given to this rare complication when FLT3 inhibitors are used for acute myeloid leukemia therapy, and appropriate treatments need to be administered in a timely manner.

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.

Sweet syndrome following the ChAdOx1-S vaccine.

We report a case of vaccine-induced Sweet syndrome in a female patient in her 50s presenting with fevers and a scattered red patchy rash on the lower limbs. Seven days prior, she had received the first dose of AstraZeneca ChAdOx1-S vaccine. A skin biopsy confirmed Sweet syndrome. She did not respond to high doses of prednisolone and required methotrexate therapy to induce remission. This is one of the first reports of Sweet syndrome caused by the ChAdOx1-S vaccine and provides further evidence for vaccine-induced dermatosis. This case demonstrates that methotrexate can induce remission in cases of Sweet syndrome resistant to corticosteroids. This report also describes an approach to the differential diagnosis of patients presenting with a rash, fever and malaise.

Azathioprine hypersensitivity: A Sweet-like syndrome.

INTRODUCTION: Azathioprine hypersensitivity can occasionally present as Sweet-like syndrome, a dose-independent side effect characterized by the unanticipated onset of macules, papules, and pustules. CASE PRESENTATION: A 35-year-old woman with systemic lupus erythematosus presented with complaints of generalized maculopapular rash, facial swelling, and bilateral lower extremity edema with a duration of 4 days and a 2-day history of constitutional symptoms within 2 weeks of the beginning of azathioprine therapy to treat existing lupus nephritis (class 2/3). DISCUSSION: Patients who experience azathioprine hypersensitivity syndrome can present with erythema nodosum, small-vessel vasculitis, acute generalized exanthematous pustulosis, Sweet syndrome, and nonspecific dermatosis. The following signs and symptoms are used as criteria to diagnose drug-induced Sweet syndrome: (a) abrupt onset of painful erythematous plaques, (b) histopathological evidence of dense neutrophilic infiltrate without evidence of leukocytoclastic vasculitis, (c) temperature higher than 39.7°C, (d) temporal relationship between drug ingestion and clinical presentation, and (e) temporal resolution of lesions after drug withdrawal. Our patient met three out of five criteria and was diagnosed with Sweet-like syndrome. CONCLUSION: Our case highlights the uncommonly presented azathioprine-induced Sweet-like syndrome that occurs abruptly after the commencement of the offending drug. This diagnosis can be established through basic laboratory workup and skin biopsy findings.

Neutrophilic fixed drug eruption, a histopathologic variant or an expected finding?-A report of two cases and review of the literature.

Fixed drug eruption (FDE) is an adverse drug reaction characterized by recurrent circumscribed lesions at the same location upon re-exposure to the culprit medication, resulting in distinct postinflammatory hyperpigmentation. Histopathologically, FDE demonstrates a predominantly lymphocytic interface or lichenoid infiltrate with basal cell vacuolar changes and keratinocyte dyskeratosis/apoptosis. The term "neutrophilic fixed drug eruption" has been used to describe cases in which the inflammatory infiltrate is predominantly neutrophilic. The infiltrate can extend deeper in the dermis, potentially mimicking a neutrophilic dermatosis such as Sweet syndrome. We present two cases and review the literature to discuss the possibility that a neutrophilic inflammatory infiltrate may be an expected finding in FDE, rather than a histopathologic variant.

Clinical characteristics, diagnosis and management of Sweet syndrome induced by azathioprine.

Sweet syndrome is a rare complication of azathioprine treatment with unelucidated clinical features. The purpose of this study was to investigate the clinical characteristics of azathioprine-induced Sweet syndrome (AISS) and provide a reference for diagnosis, treatment and prognosis. We collected relevant case reports of AISS by searching Chinese and English databases from 1960 to December 31, 2022, extracted the data and carried out a retrospective analysis. The median age of the 44 patients was 50 (range 9-89) years, and they included 32 males (72.7%). Fever (86.4%) and arthralgia (31.8%) were the most common clinical symptoms. The skin lesions were mainly pustules (54.5%), papules (40.9%), plaques (40.9%) and nodules (31.8%), which were mainly distributed on the extremities (54.5%), face (38.6%) and hands (36.4%). Laboratory examination revealed neutropenia (65.9%) as well as elevated C-reactive protein (63.6%) and erythrocyte sedimentation (40.9%) rates. Histopathology of the lesioned skin showed neutrophil infiltration (93.2%) and dermal edema (38.6%). Symptom relief was achieved at a median time of 7 days (range 2-28 days) after azathioprine discontinuation in all patients. Nine patients (20.5%) had skin lesions that recurred within 24 h after taking azathioprine again. Clinicians and pharmacists should grasp the regularity and characteristics of AISS and should not recommend the readministration of azathioprine, to avoid the recurrence of Sweet syndrome.

Dupilumab-Associated Sweet Syndrome.

Sweet syndrome (SS), also known as acute febrile neutrophilic dermatosis, is characterized by the abrupt appearance of edematous and erythematous papules, plaques, or nodules on the skin that have a distinct histopathologic appearance. Several subtypes of SS exist, including classic (also referred to as idiopathic) and drug induced. Although multiple medications have been implicated as causative agents, we present a rare case of SS caused by dupilumab, a monoclonal antibody therapy, used in the treatment of severe eosinophilic asthma and other conditions. Clinicians should be aware of this potential adverse reaction, as prompt recognition and treatment are essential.

Sweet syndrome induced by SARS-CoV-2 vaccines: A systematic review of patient-report studies.

Since COVID-19 became a global pandemic in 2020, the development and application of SARS-CoV-2 vaccines has become an important task to prevent the spread of the epidemic. In addition to the safety and efficacy of COVID-19 vaccines, the adverse reactions caused by vaccines in a small number of people also deserve our attention. We aimed to discuss and analyze the possible causes of Sweet syndrome caused by the COVID-19 vaccine by integrating the effective information from 16 patients and combining it with the latest views on the innate immune mechanism. We searched the PubMed and Embase databases for published patient reports on the occurrence or recurrence of Sweet syndrome after COVID-19 vaccination. We summarized the basic information of the patients, the type of vaccination, the presence of underlying diseases, and the clinical manifestations, clinical treatment and prognosis of the patients. The results were reported in narrative methods and were sorted into tables. We initially identified 53 studies. 16 articles were included through full-text screening. Based on the table we compiled, we generally concluded that the first dose of any type of COVID-19 vaccine was more likely to cause Sweet syndrome than subsequent doses. Sweet syndrome may occur after COVID-19 vaccination. Clinicians should consider Sweet syndrome in addition to common adverse reactions such as anaphylaxis and infection when a patient presents with acute fever accompanied by nodular erythema, pustules, and edematous plaques after COVID-19 vaccination.

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.

Adalimumab Biosimilar-Induced Autoimmunity-Related Sweet-Like Neutrophilic Dermatosis.

ABSTRACT: Antitumor necrosis factor therapies have shown to produce a broad range of cutaneous eruptions. We report the case of a patient under adalimumab biosimilar treatment for a punctate inner choroidopathy who developed a cutaneous eruption on sun-exposed areas that showed a diffuse dermal neutrophilic infiltrate consistent with a Sweet-like neutrophilic dermatosis and some features of autoimmunity.

Acute iododerma presenting as cryptococcoid neutrophilic dermatosis: A clinicopathological pitfall and interesting findings gleaned from a review of the literature.

Iododerma is an uncommon dermatosis caused by excessive iodine exposure and is associated with significant morbidity and mortality. Because of its heterogenous clinical presentation and variable histopathological findings, which depend on the time the skin biopsy is performed, the diagnosis of iododerma is often delayed. We report a rare case of acute iododerma in a woman with end-stage diabetic nephropathy with antecedent radioiodine contrast exposure, presenting histopathologically as cryptococcoid neutrophilic dermatosis (CND). We underscore important clinicopathological pitfalls to avoid misdiagnosis with similar overlapping entities such as Sweet syndrome, review all published cases of CND and draw novel insights into its associated entities.

Azathioprine hypersensitivity syndrome manifesting as subcutaneous Sweet syndrome and acute pancreatitis.

Azathioprine (AZA) is a commonly used immunosuppressive therapy that has been implicated in a number of cutaneous and systemic inflammatory reactions. Initiation of AZA has been associated with a hypersensitivity syndrome manifesting as acute pancreatitis and Sweet syndrome. Subcutaneous Sweet syndrome is a rare variant of Sweet syndrome where the dominant localization of inflammation is within the subcutaneous fat; it is commonly associated with underlying myeloproliferative disease. However, it has not been reported in the literature as a cutaneous manifestation of AZA hypersensitivity syndrome. We present a unique case of acute pancreatitis and biopsy-proven subcutaneous Sweet syndrome following the initiation of AZA with resolution upon discontinuation.

A case of filgrastim-induced neutrophilic dermatosis of the dorsal hands in a patient with Felty Syndrome.

Neutrophilic dermatosis of the dorsal hands (NDDH) is a variant of Sweet syndrome that presents with erythematous bullae, papules/plaques, or pustules on the dorsal hands. It is most commonly associated with hematologic and solid organ malignancies, though cases of NDDH associated with inflammatory bowel disease, rheumatologic disorders, and medication exposure have also been described in the literature. Felty syndrome is a rare complication of long-standing rheumatoid arthritis characterized by neuropathy, splenomegaly, and neutropenia. Granulocyte colony stimulating factors (e.g., filgrastim) can be utilized to rescue the neutropenia observed in Felty syndrome, but this treatment may subsequently cause Sweet syndrome. Herein, we present a 64-year-old man with Felty syndrome and a complex medical history who presented with sudden onset, painful blisters located on the dorsal and palmar aspects of his bilateral hands. Given the patient's past medical history, a broad differential diagnosis, including disseminated fungal and viral infection was initially considered. A punch biopsy of the skin lesion disclosed neutrophilic dermatosis, which together with laboratory data satisfied the von den Driesch criteria for Sweet syndrome. As the lesions were localized exclusively on the patient's hands, the qualification of NDDH was also endorsed.

A striking presentation of pustular Sweet syndrome induced by trimethoprim-sulfamethoxazole.

We describe a strikingly robust presentation of trimethoprim-sulfamethoxazole (TMP-SMX)-induced pustular Sweet syndrome and discuss how to distinguish it from iododerma and other neutrophil-rich conditions. A review of the literature indicates that TMP-SMX-induced Sweet syndrome (SS) may have higher rates of neutrophilia and greater ocular, mucosal, and musculoskeletal involvement compared to SS from other drugs. Recognizing these features and identifying the offending agent are critical for correctly diagnosing TMP-SMX-induced SS in a timely manner.