A case of Sweet syndrome successfully treated by anti-inflammatory property of doxycycline

Annular neutrophilic dermatoses

Neutrophilic dermatoses (NDs) constitute a group of diseases characterized by sterile neutrophilic infiltrations. Many NDs usually present with infiltrated erythematous plaques, nodules, urticarial plaques, or pustules. Lesions may show variability, and atypical presentations may develop among NDs. Annular lesions have been reported in many NDs and may lead to diagnostic problems. Clinical features and histopathologic findings such as localization of the neutrophilic infiltrate, existence of other cell types, and absence of true vasculitis may be helpful to distinguish NDs. Some of these NDs are associated with infections, inflammatory diseases, and malignancies. In most NDs, systemic steroids and dapsone are very effective and usually first choices. Colchicine, antimicrobials such as doxycycline, tetracycline, and sulfapyridine, and other immunosuppressants such as cyclosporin, methotrexate, and mycophenolate mofetil have been used successfully in treating many NDs. Tumor necrosis factor α inhibitors have also been used successfully in treating many NDs. Janus kinase inhibitors are effective in CANDLE (chronic atypical neutrophilic dermatosis with lipodystrophy and elevated temperature) syndrome, anakinra in neutrophilic urticarial dermatosis, and intravenous immunoglobulin in resistant pyoderma gangrenosum. We discuss the diagnosis and management of NDs that may present with annular lesions.

Doxycycline, an Antibiotic or an Anti-Inflammatory Agent? The Most Common Uses in Dermatology

Doxycycline is a synthetic tetracycline that was approved in 1967. This wide-spectrum antibiotic has been shown to also have useful anti-inflammatory properties that make it suitable for the treatment of a number of noninfectious conditions. Tetracyclines are probably the most commonly prescribed antibiotics in dermatology, where they are usually used at doses lower than those effective against infections. They also have an excellent efficacy and safety profile. Because of doxycycline's ability to inhibit the molecular pathways associated with certain processes, this antibiotic can be used to treat hair follicle diseases, granulomatous diseases, and vascular proliferation, among other conditions. The main properties of doxycycline and its many applications in dermatology make this drug one that specialists should become familiar with.

Recurrent Idiopathic Sweet Syndrome - Case Report and Literature Review

INTRODUCTION

Sweet syndrome (SS), also denominated as acute febrile neutrophilic dermatosis, is a rare disease characterized by the sudden onset of painful, erythematous, firm skin lesions (papules, plaques, and nodules) which show, upon histologic examination, the presence of a diffuse infiltrate of mature neutrophils. The cutaneous manifestation typically involves the face, neck, trunk, and upper limbs and is associated with fever, general malaise, arthralgia.

CASE REPORT

A female patient, 60 years old, attended the Dermatology Clinic due to the appearance of violaceous erythematous-oedematous infiltrated plaques, located on the face, neck, upper limbs, trunk and knees. The onset of the cutaneous manifestation had occurred 2 months prior, accompanied by pain, chills, flares of fever and arthralgia. The onset coincided with the surgical treatment of an umbilical hernia. From the medical history we note that the patient was diagnosed in 2014 with histiocytoid SS. She followed a treatment with methylprednisolone, with positive response, but had many relapses after the discontinuation of treatment. In 2017, due to a new episode, the histopathological examination was repeated, which revealed classical SS. She received treatment with Disulone and Colchicine. She had not been administered any treatment throughout the previous year. Laboratory tests revealed leukocytosis with neutrophils, increased ESR, elevated C4, hyperglycemia. The current histopathological examination revealed lymphocytic SS. Under treatment with methylprednisolone 32mg/day, the evolution was favorable.

DISCUSSIONS

The first case of SS was described by Robert Douglas Sweet in 1964. As known aetiological factors there have been described gastrointestinal and urinary tract infections, pregnancy, inflammatory bowel disease, drugs or malignancies. There have been described cases of SS that appeared after surgical treatment, as in our case, which registered a new outbreak following the umbilical hernia treatment. The histopathological variants of SS described in the literature are: subcutaneous, eosinophilic, histiocytoid, lymphocytic type. The first line-therapy consists in systemic corticosteroids, which induce a fast remission of lesions and general symptoms. Recurrence may occur in approximately 50% of patients and is common in idiopathic or paraneoplastic cases.

CONCLUSIONS

In addition to the neutrophilic infiltrate that is typical for Sweet syndrome, different types of histological manifestations have been described in the literature: subcutaneous, eosinophilic, histiocytoid, lymphocytic. In our case, we noted that the histological profile changed over time, from a histiocytoid SS recorded in 2014, to a classical SS in 2017, followed by the appearance of lymphocytic SS in 2019. Due to the fact that SS can be associated with a numerous other disorders, our patient requires regular monitoring with a view to eliminate them, and potentially to make a diagnosis and initiate early specific treatment.

Neutrophilic dermatoses: Pathogenesis, Sweet syndrome, neutrophilic eccrine hidradenitis, and Behçet disease

Neutrophilic dermatoses are a heterogeneous group of inflammatory skin disorders that present with unique clinical features but are unified by the presence of a sterile, predominantly neutrophilic infiltrate on histopathology. The morphology of cutaneous lesions associated with these disorders is heterogeneous, which renders diagnosis challenging. Moreover, a thorough evaluation is required to exclude diseases that mimic these disorders and to diagnose potential associated infectious, inflammatory, and neoplastic processes. While some neutrophilic dermatoses may resolve spontaneously, most require treatment to achieve remission. Delays in diagnosis and treatment can lead to significant patient morbidity and even mortality. Therapeutic modalities range from systemic corticosteroids to novel biologic agents, and the treatment literature is rapidly expanding. The first article in this continuing medical education series explores the pathogenesis of neutrophilic dermatoses and reviews the epidemiology, clinical and histopathologic features, diagnosis, and management of Sweet syndrome, neutrophilic eccrine hidradenitis, and Behçet disease.