Insights Into the Characteristics of Sweet Syndrome in Patients With and Without Hematologic Malignancy

Neutrophilic and eosinophilic dermatoses associated with hematological malignancy

Cutaneous manifestations of hematologic malignancy represent both a clinical challenge for the treating physician and a pathophysiological model for advancing the knowledge on individual neoplasms. Indeed, a growing body of evidence supports the concept of recurrent molecular defects associating with specific clinical features, as best exemplified by VEXAS. Herein neutrophilic and eosinophilic dermatoses of potential interest for both hematologists and dermatologists will be reviewed, including subcorneal pustular dermatosis-type IgA pemphigus, neutrophilic eccrine hidradenitis, Sweet's syndrome as well as myelodysplasia cutis and VEXAS, pyoderma gangrenosum, eosinophilic annular erythema, eosinophilic dermatosis of hematological malignancy, Wells syndrome and cutaneous involvement in hypereosinophilic syndromes. Possible management approaches are discussed for each, emphasizing scenarios that require treatment of the underlying condition to achieve remission at the skin level.

An uncommon culprit of neutropenic fever: a case of Sweet syndrome following induction therapy for acute myeloid leukemia

Sweet syndrome (SS) is a rare inflammatory disorder characterized by the rapid onset of a characteristically tender rash, fever, and other systemic symptoms. These manifestations are often mistaken for an infection that is not responding to antimicrobials, especially in immunocompromised hosts. We present the case of a 44-year-old woman who developed SS following induction chemotherapy for newly diagnosed acute myeloid leukemia (AML). She exhibited a painful rash on the anterior chest, which spread centrifugally, along with neutropenic fever unresponsive to broad-spectrum antimicrobials. Biopsy of the rash revealed a dense neutrophilic infiltrate within the dermis, confirming the diagnosis of SS. The patient was subsequently treated with systemic steroids with prompt resolution of fevers and improvement of her rash. This case highlights that SS can manifest with a robust neutrophilic infiltrate, even in the context of neutropenia stemming from chemotherapy. SS serves as a crucial consideration in hematologic malignancies, particularly AML, when patients present with fever and cutaneous eruptions. Prompt recognition followed by systemic steroid therapy often leads to symptom resolution.

Giant Cellulitis-Like Sweet Syndrome Masquerading As Cellulitis and Shingles: A Case Report and Literature Review

Sweet syndrome (SS) is also known as acute febrile neutrophilic dermatoses. Clinically, SS features fever, arthralgias, and the sudden onset of an erythematous rash. The morphologies of skin lesions in SS are heterogenous, varying from papules, plaques, and nodules to hemorrhagic bullae, which sometimes makes the diagnosis of SS more challenging. We report a 62-year-old obese male with a history of chronic myeloid leukemia in remission for 10 years who presented with a rash for five days. The patient reported prodromal flu-like symptoms with subjective fever, malaise, cough, and nasal congestion followed by a sudden onset, painful, non-pruritic rash. The rash was associated with bilateral hip arthralgias and abdominal pain. The patient denied any recent travel, exposure to sick contacts, or the use of any new medications. Physical examination showed a well-demarcated, non-blanching, confluent, erythematous plaque involving the bilateral buttocks and extending to the lower back and flanks with coalescent "juicy"-appearing plaques and flaccid bullae. No oral or mucosal involvement was noted. Laboratory investigations revealed mild leukocytosis, elevated inflammatory markers, and acute kidney injury. The patient was started on antibiotics given the cellulitis-like skin lesions, leukocytosis with neutrophilia, and elevated inflammatory markers. Dermatology was consulted, who attributed the patient's rash to shingles and recommended initiating acyclovir and obtaining a skin biopsy. However, the patient's rash and arthralgias worsened with anti-viral treatment while awaiting pathology results. Antinuclear antibodies, complement, human immunodeficiency virus, hepatitis panel, blood cultures, and tumor markers were all negative. Flow cytometry showed no evidence of hematopoietic neoplasms. The skin punch biopsy revealed dense neutrophilic infiltration in the dermis with no evidence of leukocytoclastic vasculitis, consistent with acute neutrophilic dermatoses. The diagnosis of giant cellulitis-like Sweet syndrome was established, and the patient was started on prednisone 60 milligrams daily. His symptoms improved promptly with steroid treatment. Our case suggests that SS can camouflage a wide spectrum of diseases, including cellulitis, shingles, vasculitis, drug eruptions, leukemia cutis, and sarcoidosis, which emphasizes the importance of keeping a high index of suspicion for SS when assessing the clinical constellations of fever, neutrophilia, and erythematous plaques suggesting atypical cellulitis. Approximately 21% of Sweet syndrome is associated with malignancy. Sweet syndrome can precede, concur with, or follow the onset of malignancy. Due to the lack of a systematic approach to patients with SS, under-investigation and diagnostic delays are common. Therefore, further screening and continuous monitoring in patients with SS becomes especially important in facilitating the early detection of a potential underlying malignancy and assists in initiating adequate therapy.

New Practical Aspects of Sweet Syndrome

Sweet syndrome (SS), or acute febrile neutrophilic dermatosis, is an inflammatory, non-infectious skin reaction characterized clinically by tender, erythematous papules/plaques/pustules/nodules commonly appearing on the upper limbs, trunk, and head and neck; histologically, SS is characterized by dense neutrophilic infiltrate in the dermis. SS is accompanied by fever; an elevation of inflammatory markers (e.g., erythrocyte sedimentation rate, C reactive protein) in serum may also be observed. Although most cases of SS are idiopathic, SS also occurs in the setting of malignancy or following administration of an associated drug. SS has also been reported in association with pregnancy and a burgeoning list of infectious (most commonly upper respiratory tract infections) and inflammatory diseases; likewise, the litany of possible iatrogenic triggers has also grown. Over the past several years, a wider spectrum of SS presentation has been realized, with several reports highlighting novel clinical and histological variants. Corticosteroids continue to be efficacious first-line therapy for the majority of patients with SS, although novel steroid-sparing agents have been recently added to the therapeutic armamentarium against refractory SS. New mechanisms of SS induction have also been recognized, although the precise etiology of SS still remains elusive. Here, we catalogue the various clinical and histological presentations of SS, summarize recently reported disease associations and iatrogenic triggers, and review treatment options. We also attempt to frame the findings of this review in the context of established and emerging paradigms of SS pathogenesis.

Neutrophilic Dermatoses: a Clinical Update

Purpose of Review

Neutrophilic dermatoses are defined by the presence of a sterile neutrophilic infiltrate on histopathology. This review focuses on the pathogenesis, epidemiology, clinicopathological features, diagnosis, and management of four disorders: Sweet syndrome, pyoderma gangrenosum, Behçet syndrome, and neutrophilic eccrine hidradenitis.

Recent Findings

Recent studies have provided insight into the complex pathogenesis of neutrophilic dermatoses. Evidence supports an intricate interplay of abnormal neutrophil function and inflammasome activation, malignant transformation into dermal infiltrating neutrophils, and genetic predisposition.

Summary

Neutrophilic dermatoses have diverse cutaneous and extracutaneous manifestations and may be associated with significant morbidity and mortality. Common underlying associations include infectious, inflammatory, and neoplastic disorders, as well as drug reactions. Emerging diagnostic and therapeutic frameworks identify an expanding role for biologic and targeted anti-inflammatory therapies.

Immune-Mediated Cutaneous Paraneoplastic Syndromes Associated With Hematologic Malignancies: Skin as a Mirror of Hematologic Neoplasms

Malignant neoplasms may present as paraneoplastic syndromes with mucocutaneous manifestations, which may or may not be chronologically associated. The pathophysiological mechanism is complex and not completely understood; therefore, definitive diagnosis may be achieved with a precise differential diagnosis based on the morphology of skin lesions, clinical picture, and histological pattern. The complexities, and low frequency, make the therapeutic approach quite challenging; consequently, the cornerstone of therapy is the eradication of the underlying neoplasms. Corticosteroids are the therapy of choice for most of these immune-mediated manifestations, but for the most part, the successful resolution requires the eradication of the underlying malignancy.

Characteristic bone marrow findings in patients with UBA1 somatic mutations and VEXAS syndrome

VEXAS (vacuoles, E1 enzyme, X-linked, autoinflammatory, somatic) is a newly characterized syndrome with underlying somatic UBA1 mutations in myeloid cells linking hematologic disease with autoinflammatory rheumatologic disorders. Hematologic abnormalities, particularly peripheral blood cytopenia(s) may prompt bone marrow evaluation in patients with known or unrecognized VEXAS syndrome. This review highlights key findings and diagnostic considerations encountered during bone marrow examination in patients with this disorder. Frequently reported hematologic changes include macrocytic anemia, cytoplasmic vacuoles in myeloid and erythroid precursors, marrow hypercellularity, and varying degrees of dysplasia. Myelodysplastic syndrome and plasma cell neoplasms have been diagnosed in patients with VEXAS syndrome. Macrophage activation syndrome and/or hemophagocytic lymphohistiocytosis and monoclonal B-cell lymphocytosis have also been reported. The bone marrow is a target organ in VEXAS syndrome. Heightened awareness of the bone marrow features and hematologic complications may aid in identifying individuals with VEXAS who may benefit from increased disease surveillance or alternative therapeutic strategies.

Systematic Review: Sweet Syndrome Associated with Inflammatory Bowel Disease

BACKGROUND AND AIMS

Sweet syndrome [SS] is a dermatological condition associated with both inflammatory bowel disease [IBD] and azathioprine use. We performed a systematic review to better delineate clinical characteristics and outcomes of SS in IBD patients.

METHODS

Peer-reviewed, full-text journal publications from inception to April 2020 in English language and adult subjects with IBD were included. Skin biopsy was required as SS gold-standard diagnosis. Azathioprine-associated SS required recent azathioprine introduction or recurrence of SS after azathioprine re-challenge.

RESULTS

We included 89 publications with 95 patients [mean age of SS diagnosis: 44 years; 59% female; 20 with azathioprine-associated SS and 75 without]. SS was diagnosed prior to IBD in 5.3%, at time of IBD diagnosis in 29.5% and after diagnosis in 64.2%. In total, 91% of patients with SS had known colonic involvement and the majority [76%] had active IBD at diagnosis; 22% had additional extra-intestinal manifestations. Successful therapies for SS included corticosteroids [90.5%], anti-tumour necrosis factor [TNF]-α inhibitor therapy [14.8%] and azathioprine [11.6%]. Azathioprine-associated SS was distinct, with 85% male patients, mean age of SS diagnosis of 50 years and a lower likelihood to be prescribed corticosteroids for treatment [75% vs 94.7% of non-azathioprine-associated SS, p = 0.008]. All patients with azathioprine-associated SS improved with medication cessation and developed recurrence after re-challenge.

CONCLUSIONS

SS may precede or occur with IBD diagnosis in almost one-third of cases. Azathioprine and IBD-associated SS present and behave distinctly, especially with regard to gender, age at diagnosis and recurrence risk. Corticosteroids and TNF-α inhibitors have demonstrated efficacy in treating SS in IBD.

Diagnosis of Sweet's syndrome in otolaryngology

Sweet's syndrome (acute febrile neutrophilic dermatosis) consists of acute onset of painful cutaneous erythematous lesions, mostly found in the upper extremities followed by the head and neck region, particularly in patients with underlying malignancies. We describe the case of a woman in her mid-30s, who was treated for acute myeloid leukaemia and presented with a severe painful and progressive erythematous lesion of the retroauricular skin. Clinical features, laboratory tests, blood cultures and histological biopsy yielded a diagnosis of Sweet's syndrome. The treatment consisted of oral and topical corticosteroids and her signs and symptoms resolved within 1 week. Although Sweet's syndrome is uncommon, awareness among otolaryngologists is crucial to ensure a prompt diagnosis, cure and referral to an oncologist (if not already involved) for patients with Sweet's syndrome in the head and neck area.

Pirfenidone modifies hepatic miRNAs expression in a model of MAFLD/NASH

miRNAs are involved in the development of metabolic associated fatty liver disease (MAFLD) and nonalcoholic steatohepatitis (NASH). We aimed to evaluate modifications by prolonged-release pirfenidone (PR-PFD) on key hepatic miRNAs expression in a MAFLD/NASH model. First, male C57BL/6J mice were randomly assigned into groups and fed with conventional diet (CVD) or high fat and carbohydrate diet (HFD) for 16 weeks. At the end of the eighth week, HFD mice were divided in two and only one half was treated with 300 mg/kg/day of PR-PFD mixed with food. Hepatic expression of miRNAs and target genes that participate in inflammation and lipid metabolism was determined by qRT-PCR and transcriptome by microarrays. Increased hepatic expression of miR-21a-5p, miR-34a-5p, miR-122-5p and miR-103-3p in MAFLD/NASH animals was reduced with PR-PFD. Transcriptome analysis showed that 52 genes involved in lipid and collagen biosynthesis and inflammatory response were downregulated in PR-PFD group. The expression of Il1b, Tnfa, Il6, Tgfb1, Col1a1, and Srebf1 were decreased in PR-PFD treated animals. MAFLD/NASH animals compared to CVD group showed modifications in gene metabolic pathways implicated in lipid metabolic process, inflammatory response and insulin resistance; PR-PFD reversed these modifications.

Transformation of a myelodysplastic syndrome to acute myeloid leukemia and concurrent necrotizing sweet syndrome

The Sweet's syndrome, is an inflammatory skin disorder characterized by extensive infiltration of neutrophils in the dermis with extension to the subcutis, known as acute febrile neutrophilic dermatosis. It may occur as a paraneoplastic syndrome. To our knowledge, there are currently few reports about transformation of a myelodysplastic syndrome to acute myeloid leukemia and concurrent necrotizing Sweet syndrome in the literature. Herein we describe an unusual case in a young patient with these characteristics that evolved to a fatal outcome.

A diffuse rash in a patient after allogeneic hematopoietic stem cell transplant for AML

Sweet's syndrome associated with relapse of leukemia suggests abnormal neutrophil response to transformation of dysfunctional leukemia blast cells, and hence, relapse should be excluded in similar clinical situation.