Sweet's syndrome in chronic lymphocytic leukemia associated with neutropenic fever and granulocyte colony stimulation factor

Amelioration of cyclophosphamide-induced myelosuppression during treatment to rats with breast cancer through low-intensity pulsed ultrasound

To investigate the alleviating effects of low-intensity pulsed ultrasound (LIPUS) on myelosuppression of Sprague–Dawley rats with breast cancer induced by cyclophosphamide (CTX). Breast cancer in rats was triggered by intragastric gavage with 7,12-dimethylbenz[a]anthracene (150 mg/kg). Then, the rats with breast cancer were randomly allocated to the LIPUS group (n=50) and the control group (n=50). The LIPUS group was injected intraperitoneally with CTX (50 mg/kg) for 4 consecutive days and underwent LIPUS treatment at femoral metaphysis 20 min per day from the first day of injection for 7 consecutive days. The control group was injected with CTX (50 mg/kg) and treated with LIPUS without energy output. Blood, enzyme-linked immunosorbent assay (ELISA), real-time quantitative polymerase chain reaction, Hematoxylin and Eosin (H&E) staining, and scanning electron microscopy were applied to detect the changes. The results indicated that LIPUS significantly promoted the proliferation of bone marrow nucleated cells, white blood cells (WBCs), IgA, IgG, and IgM in the peripheral blood (P<0.05) without the damage to liver and kidney function simultaneously. The mechanisms may result from the LIPUS alleviation effect on bone marrow hematopoietic function through regulating cytokines such as LIPUS can increase the expression of granulocyte colony-stimulating factor (G-CSF), stem cell factor, transforming growth factor-β, and intercellular cell adhesion molecule-1, meanwhile LIPUS will decrease the expression of interleukin-6, tumor necrosis factor-α, and vascular cell adhesion molecule-1. LIPUS has potential to be a new adjuvant therapy method in clinic for ameliorating chemotherapy-induced myelosuppression.

Insights Into the Pathogenesis of Sweet's Syndrome

Sweet's syndrome, also known as Acute Febrile Neutrophilic Dermatosis, is a rare inflammatory condition. It is considered to be the prototype disease of neutrophilic dermatoses, and presents with acute onset dermal neutrophilic lesions, leukocytosis, and pyrexia. Several variants have been described both clinically and histopathologically. Classifications include classic Sweet's syndrome, malignancy associated, and drug induced. The cellular and molecular mechanisms involved in Sweet's syndrome have been difficult to elucidate due to the large variety of conditions leading to a common clinical presentation. The exact pathogenesis of Sweet's syndrome is unclear; however, new discoveries have shed light on the role of inflammatory signaling, disease induction, and relationship with malignancy. These findings include an improved understanding of inflammasome activation, malignant transformation into dermal infiltrating neutrophils, and genetic contributions. Continued investigations into effective treatments and targeted therapy will benefit patients and improve our molecular understanding of inflammatory diseases, including Sweet's syndrome.

Rituximab for refractory subcutaneous Sweet's syndrome in chronic lymphocytic leukemia: A case report

Sweet's syndrome is a neutrophilic dermatosis characterised by sudden onset of fever, neutrophilia, erythematous skin rashes and neutrophilic infiltration of the dermis. Subcutaneous Sweet's syndrome, or Sweet's panniculitis, is an uncommon variant of the classic syndrome, with hypodermal neutrophilic infiltration. The association of Sweet's syndrome with various malignancies has been reported. The most common underlying hematological malignancies are of myeloid origin; however, there have been several reports of the classic Sweet's syndrome in patients with a lymphoproliferative disorder, although the association of subcutaneous Sweet's syndrome with lymphoproliferative disorders has not been well-documented thus far. Herein, we present the case of a 48-year-old man with a 2-year history of chronic lymphocytic leukemia who developed fever and skin rashes, without any evidence of a relapse. The clinical and pathological investigation resulted in the diagnosis of subcutaneous Sweet's syndrome. The patient exhibited no significant response to conventional therapeutic measures; however, following two subsequent doses of rituximab, his general condition and skin rash improved. The follow-up skin biopsy demonstrated dermal neutrophilic infiltrations in conjunction with prior mixed lobular and septal panniculitis, suggesting evolution of subcutaneous Sweet's syndrome to its classic form. To the best of our knowledge, this is one of the first reports of rituximab as a novel biological treatment for Sweet's syndrome. However, further randomized trials are required to evaluate the efficacy and safety of such biological therapies for Sweet's syndrome.

Side effects of cytokines approved for therapy

Cytokines, currently known to be more than 130 in number, are small MW (<30 kDa) key signaling proteins that modulate cellular activities in immunity, infection, inflammation and malignancy. Key to understanding their function is recognition of their pleiotropism and often overlapping and functional redundancies. Classified here into 9 main families, most of the 20 approved cytokine preparations (18 different cytokines; 3 pegylated), all in recombinant human (rh) form, are grouped in the hematopoietic growth factor, interferon, platelet-derived growth factor (PDGF) and transforming growth factor β (TGFβ) families. In the hematopoietin family, approved cytokines are aldesleukin (rhIL-2), oprelvekin (rhIL-11), filgrastim and tbo-filgrastim (rhG-CSF), sargramostim (rhGM-CSF), metreleptin (rh-leptin) and the rh-erythropoietins, epoetin and darbepoietin alfa. Anakinra, a recombinant receptor antagonist for IL-1, is in the IL-1 family; recombinant interferons alfa-1, alfa-2, beta-1 and gamma-1 make up the interferon family; palifermin (rhKGF) and becaplermin (rhPDGF) are in the PDGF family; and rhBMP-2 and rhBMP-7 represent the TGFβ family. The main physicochemical features, FDA-approved indications, modes of action and side effects of these approved cytokines are presented. Underlying each adverse events profile is their pleiotropism, potency and capacity to release other cytokines producing cytokine 'cocktails'. Side effects, some serious, occur despite cytokines being endogenous proteins, and this therefore demands caution in attempts to introduce individual members into the clinic. This caution is reflected in the relatively small number of cytokines currently approved by regulatory agencies and by the fact that 14 of the FDA-approved preparations carry warnings, with 10 being black box warnings.

Sweet syndrome in a patient with chronic lymphocytic leukemia/small lymphocytic lymphoma: curious lymphocyte/neutrophil fluctuations

Sweet syndrome, also referred to as acute febrile neutrophilic dermatosis, is characterized by tender, red inflammatory nodules or papules that occur in association with infection, malignancy, connective tissue disease, or following exposure to certain drugs. Here, we present Sweet syndrome in a case with small lymphocytic lymphoma/chronic lymphocytic leukemia (SLL/CLL) which is a relatively rare co-occurrence.

CONFLICT OF INTEREST

None declared.

Necrotizing Sweet syndrome: a new variant of neutrophilic dermatosis mimicking necrotizing fasciitis

BACKGROUND

We report a series of patients initially given the diagnosis of necrotizing fasciitis whose course progressed despite surgical debridement, antibiotic therapy, or both, but who responded rapidly to systemic corticosteroids.

OBJECTIVE

We sought to evaluate the clinical data, histopathologic and microbiology information, and treatment course of this unusual entity.

METHODS

This was a descriptive study/case series.

RESULTS

Three immunocompromised patients who presented with signs and symptoms of necrotizing fasciitis were included. They appeared septic, failed multiple courses of antibiotics, demonstrated pathergy, and two of them underwent extensive surgical debridement. None of the cases yielded a microbial source. Dermatologic consultation and histopathology confirmed deep Sweet syndrome in all cases, with marked necrosis of the soft tissue--including myonecrosis--in the two patients with debridement. All patients responded rapidly to high-dose systemic corticosteroids.

LIMITATIONS

To our knowledge, this is the first report of this unusual presentation; there are a limited number of cases.

CONCLUSION

We propose that these cases represent a new variant of neutrophilic dermatosis: "necrotizing Sweet syndrome," an acute necrotizing neutrophilic dermatosis. This subtype is also characterized by the rapid onset of progressive erythematous, warm, edematous cutaneous lesions with deep-tissue neutrophilic infiltration and soft-tissue necrosis, in the absence of infectious cause. Awareness of this entity and early dermatologic consultation is critical as debridement results in expansion of the process, resulting in additional and aggressive resection--a vicious cycle with significant possible morbidity.

EPONYM. Sweet syndrome

Sweet syndrome, also referred to as acute febrile neutrophilic dermatosis, is characterized by tender, red inflammatory nodules or papules that occur in association with infection, malignancy, connective tissue disease, or following exposure to certain drugs. Although drug-induced Sweet syndrome is rare, granulocyte colony-stimulating factor, all-trans-retinoic acid, and miscellaneous drugs have been implicated in causing this disorder in adults. In pediatric patients, granulocyte colony-stimulating factor, all-trans-retinoic acid, trimethoprim-sulfamethoxazole, and azathioprine have been implicated as potential causes of drug-induced Sweet syndrome. To date, six cases, including the patient reported here, have been reported in children.

Drug-induced Sweet's syndrome

OBJECTIVE

To systematically review the pertinent literature on drug-induced Sweet's syndrome (SS).

DATA SOURCES

MEDLINE (1966-December 2006), International Pharmaceutical Abstracts (1970-December 2006), Science Citation Index (1945-December 2006), and EMBASE (1980-December 2006) were searched using the key terms Sweet's syndrome, drug-induced, and acute neutrophilic dermatitis.

STUDY SELECTION AND DATA EXTRACTION

All case reports of drug-induced SS located using the above databases were collected for causality assessment. In addition, relevant articles regarding the various causes and presentations of SS were selected to provide background information. Bibliographies of all relevant articles were reviewed for additional citations.

DATA SYNTHESIS

All case reports of drug-induced SS were evaluated against an expanded Naranjo scale with specific criteria for SS. Tables were developed listing key criteria for evaluating the case reports for causality. Data were evaluated by quantity and quality of evidence, and an assessment was made as to whether there was a feasible pharmacologic mechanism to explain causality.

CONCLUSIONS

Granulocyte colony-stimulating factor (G-CSF), all-trans retinoic acid (ATRA), and vaccines met 2 of 3 criteria for an association with SS. There are sufficient data and a plausible pharmacologic mechanism for G-CSF and ATRA. Vaccines meet the qualitative criteria and also have a plausible pharmacologic mechanism. The evidence regarding minocycline is of high quality; however, the quantity of evidence and a reasonable pharmacologic mechanism are lacking. A host of miscellaneous drugs have also been implicated in causing the disorder, all without sufficient evidence.