Sweet syndrome in children

Pediatric Neutrophilic Dermatoses

The term neutrophilic dermatosis encompasses a heterogeneous group of diseases, often associated with an underlying internal noninfectious disease, with an overlapping histopathologic background characterized by perivascular and diffuse neutrophilic infiltrates in one or more layers of the skin; extracutaneous neutrophilic infiltrates may be associated. Neutrophilic dermatoses are not frequent in children and, when they appear in this age group, represent a diagnostic and therapeutic challenge. Apart from the classic neutrophilic dermatoses such as pyoderma gangrenosum, Sweet syndrome, and Behçet disease, a neutrophilic dermatosis can be the presentation of rare genetic diseases of the innate immune system, such as autoinflammatory diseases.

[Sweet syndrome of childhood with acquired cutis laxa (Marshall syndrome) as primary manifestation of Takayasu arteritis]

A special form of the rare infantile Sweet syndrome (acute febrile neutrophilic dermatosis) is facultative healing in the form of postinflammatory elastolysis with acquired cutis laxa, named "Marshall" syndrome after the authors who first described it. We report the case of a 3-year-old child in whom the cutaneous manifestation led to diagnosis of Takayasu arteritis. Postinflammatory elastolysis with acquired cutis laxa is a clinically relevant cutaneous indicator of life-threatening cardiovascular complications such as aortitis, aortic aneurysm, coronary stenosis and heart failure in children with Sweet's syndrome. Cutis laxa usually precedes cardiac complications or, as in our case, occurs simultaneously; thus, immediate cardiac and rheumatologic examinations are important to initiate systemic therapy with anti-inflammatory and immunomodulatory agents early to prevent complications.

Sweet Syndrome in an Adolescent Patient With Differentiation Syndrome Secondary to Promyelocytic Leukemia Treatment With All-Trans Retinoic Acid

Sweet syndrome (SS) is an acute febrile neutrophilic dermatosis that is histologically characterized by an infiltration of the dermis by neutrophils. A 12-year-old adolescent female patient recently diagnosed with acute promyelocytic leukemia presented with fever and was hospitalized for antibiotic management after 22 days of being treated with a treatment protocol based on daunorubicin, all-trans retinoic acid (ATRA), and prophylaxis with dexamethasone, the patient developed erythematous skin lesions located mostly on the extremities. Lesions evolved into painful subcutaneous nodules, and one lesion evolved into a 2.5-cm blister with a purple and necrotic base. A skin biopsy was performed and showed neutrophilic dermatosis which confirmed the diagnosis of SS. The patient's clinical features complied with criteria for differentiation syndrome complicated by shock. Two days after ATRA was suspended, the patient presented resolution of the fever and skin lesions. SS is a rare neutrophilic dermatosis secondary to an innate immune disorder classified into four categories: classical (idiopathic), para-inflammatory, paraneoplastic or pregnancy-related. SS has been described in patients with acute myeloid leukemia in adults secondary to the use of drugs such as ATRA or as a part of a paraneoplastic syndrome. SS can occur exceptionally in children with myeloid leukemia secondary to the use of drugs such as ATRA.

Kikuchi-Fujimoto Disease With Unusual Cutaneous Findings

ABSTRACT

We present a case of the rare Kikuchi-Fujimoto disease (KFD) in a 14-year-old patient admitted to UCLA Medical Center with fever, weight loss, and pancytopenia. Physical examination revealed tender subcutaneous nodules and cervical lymphadenopathy. A lymph node biopsy showed findings consistent with KFD. The skin biopsy showed mild superficial dermal edema with neutrophil-predominant inflammation. In addition, rare atypical monocytoid cells were seen. This histologic finding of a Sweet-like morphology has not been reported previously in the literature in association with KFD. The differential diagnosis included Sweet syndrome arising in association with KFD, underlying connective tissue, and an infectious etiology.

Rare Vesiculopustular Eruptions of the Neonatal Period

Numerous disorders present with vesiculopustular eruptions in the neonatal period, ranging from benign to life-threatening. Accurate and prompt diagnosis is imperative to avoid unnecessary testing and treatment for benign eruptions, while allowing for adequate treatment of potentially fatal disorders. In this review, we highlight several rare blistering diseases of the newborn. A diagnostic approach is outlined to provide clinicians with a framework for approaching a neonate with vesicles, pustules, or ulcers.

Ptpn6 inhibits caspase-8- and Ripk3/Mlkl-dependent inflammation

Ptpn6 is a cytoplasmic phosphatase that functions to prevent autoimmune and interleukin-1 (IL-1) receptor-dependent, caspase-1-independent inflammatory disease. Conditional deletion of Ptpn6 in neutrophils (Ptpn6^∆PMN) is sufficient to initiate IL-1 receptor-dependent cutaneous inflammatory disease, but the source of IL-1 and the mechanisms behind IL-1 release remain unclear. Here, we investigate the mechanisms controlling IL-1α/β release from neutrophils by inhibiting caspase-8-dependent apoptosis and Ripk1-Ripk3-Mlkl-regulated necroptosis. Loss of Ripk1 accelerated disease onset, whereas combined deletion of caspase-8 and either Ripk3 or Mlkl strongly protected Ptpn6^∆PMN mice. Ptpn6^∆PMN neutrophils displayed increased p38 mitogen-activated protein kinase-dependent Ripk1-independent IL-1 and tumor necrosis factor production, and were prone to cell death. Together, these data emphasize dual functions for Ptpn6 in the negative regulation of p38 mitogen-activated protein kinase activation to control tumor necrosis factor and IL-1α/β expression, and in maintaining Ripk1 function to prevent caspase-8- and Ripk3-Mlkl-dependent cell death and concomitant IL-1α/β release.

Age-specific characteristics of neutrophilic dermatoses and neutrophilic diseases in children

BACKGROUND

Our suggested 'modern' concepts of 'neutrophilic dermatoses' (ND) and 'neutrophilic disease' were based on observations in adult patients and have not been studied in paediatric patients. Only a minority of ND occurs in children, and little is known about age-specific characteristics.

OBJECTIVES

To describe age-specific characteristics of ND in children and to study whether our suggested 'modern' classification of ND may be applied to children.

METHODS

We conducted a retrospective multicentre study in a French cohort of 27 paediatric patients diagnosed with pyoderma gangrenosum (PG) or Sweet's syndrome (SS).

RESULTS

Demographics and distribution of typical/atypical forms were similar in patients diagnosed with PG and SS. Atypical ND were more frequent in infants (90%), when compared to young children (60%) and adolescents (33%). Neutrophilic disease was observed in 17/27 patients and was most frequent in infants. Neutrophilic disease of the upper respiratory tract, as well as cardiac neutrophilic disease, was only observed in infants, whereas other locations were similarly found in infants, young children and adolescents. In infants and young children, ND were associated with a large spectrum of general diseases, whereas in adolescents associations were limited to inflammatory bowel disease and Behçet's disease.

CONCLUSIONS

Our study describes the concept of ND in paediatric patients and shows that they have some characteristics different from ND occurring in adults. ND occurring in infants can be associated with a large spectrum of general diseases. Occurrence of neutrophilic disease is frequent in children. Thus, ND occurring in young paediatric patients should incite clinicians to schedule complementary explorations in order to search for involvement of other organs and to rule out monogenetic autoinflammatory syndromes.

Bullous sweet syndrome healing with prominent secondary anetoderma

A 15-month-old boy presented with 1-4 cm, pink edematous plaques with overlying round erosions and hemorrhagic bullae in the setting of a gastrointestinal illness and was ultimately diagnosed with bullous-type Sweet syndrome. Despite appropriate treatment with oral steroids, the patient's cutaneous lesions healed with secondary anetoderma. This case should prompt practitioners to be aware of bullous-type Sweet syndrome and the possibility of lesions healing with postinflammatory scarring.

Chorea revealing systemic lupus erythematosus in a 13-year old boy: A case report and short review of the literature

Among the neurological manifestations of systemic lupus erythematosus (SLE), chorea is rare, presenting in less than 7% of the pediatric SLE patients. It can appear early in the onset of SLE, be the first or even the sole clinical feature of the illness and has strongly been associated with the presence of antiphospholipid antibodies. We report on the case of a 13-year old boy, admitted with acute onset chorea and finally diagnosed with SLE. Subsequently, we present a short review of the literature on the epidemiology, suggested pathogenesis, clinical presentation and treatment of this rare presentation of SLE.

Histiocytoid Sweet Syndrome in a Child without Underlying Systemic Disease

Sweet syndrome (acute, febrile, neutrophilic dermatosis) is characterized by the acute onset of an eruption of painful nodules or erythematous or violaceous plaques on the limbs, face and neck. These symptoms are accompanied by fever. The diagnostic features include histopathological findings of dermal neutrophilic infiltration without leukocytoclastic vasculitis or peripheral blood leukocytosis. Sweet syndrome is associated with infection, malignancies, autoimmune disease, pregnancy, and drugs. Patients with Sweet syndrome demonstrate a complete and rapid response to systemic steroid administration. Recently, a distinct variant of Sweet syndrome was reported, termed “histiocytoid Sweet syndrome”, in which the infiltration of myeloperoxidase-positive histiocytoid mononuclear cells are observed (in contrast to the infiltration of neutrophils). The other clinical features are similar to those of classic Sweet syndrome. Pediatric Sweet syndrome is uncommon, and the histiocytoid type is even rarer. To date, four cases of histiocytoid Sweet syndrome have been reported in children. Herein, we describe a case of histiocytoid Sweet syndrome in an otherwise healthy 10-year-old boy with no underlying systemic disease in whom non-steroidal, anti-inflammatory drug treatment was successful.

Neutrophilic dermatoses: Kids are not just little people

Neutrophilic dermatoses are a group of inflammatory skin disorders characterized by an overactive innate immune system with dysregulation of neutrophils without underlying infectious etiology. The major representative conditions discussed are Sweet syndrome; pyoderma gangrenosum; neutrophilic eccrine hidradenitis; palmoplantar eccrine hidradenitis; subcorneal pustular dermatoses; bowel-associated dermatosis arthritis syndrome; and synovitis, acne, pustulosis, hyperostosis, and osteitis. We will also discuss other neutrophilic conditions present almost exclusively in the pediatric population, including congenital erosive and vesicular dermatosis with reticulated supple scarring and the recently described group of autoinflammatory diseases. The clinical characteristics, diagnostic approach, and treatment management in the pediatric and adult population are discussed.

Myeloid sarcoma in children - diagnostic and therapeutic difficulties

Myeloid sarcoma (MS) is a malignant extramedullary tumour, which consists of immature cells of myeloid origin. It may occur de novo, concurrently or precede the diagnosis of acute myeloid leukemia (AML), myelodysplastic syndrome (MDS) or chronic myeloid leukemia (CML). MS can also be a manifestation of the relapse of the disease. The more frequent sites of involvement are the skin, orbit, bone, periosteum, lymph nodes, gastrointestinal tract, soft tissue, central nervous system and testis. Because of its different localization and symptoms, and the lack of diagnostics algorithm, myeloid sarcoma is a real diagnostic challenge, in particular in patients without initial bone marrow involvement. The correct diagnosis of MS is important for adequate therapy, which is often delayed because of a high misdiagnosis rate. In the paper, the role of immunohistochemistry, cytogenetic and molecular genetic analyses is emphasized as well as the breadth of unclear aspects of this disorder in children.

Periodic Fever and Neutrophilic Dermatosis: Is It Sweet's Syndrome?

A 7-year-old boy with high grade fever (39°C) and warm, erythematous, and indurated plaque above the left knee was referred. According to the previous records of this patient, these indurated plaques had been changed toward abscesses formation and then spontaneous drainage had occurred after about 6 to 7 days, and finally these lesions healed with scars. In multiple previous admissions, high grade fever, leukocytosis, and a noticeable increase in erythrocyte sedimentation rate and C-reactive protein were noted. After that, until 7th year of age, he had shoulder, gluteal, splenic, kidney, and left thigh lesions and pneumonia. The methylprednisolone pulse (30 mg/kg) was initiated with the diagnosis of Sweet's syndrome. After about 10-14 days, almost all of the laboratory data regressed to nearly normal limits. After about 5 months, he was admitted again with tachypnea and high grade fever and leukocytosis. After infusion of one methylprednisolone pulse, the fever and tachypnea resolved rapidly in about 24 hours. In this admission, colchicine (1 mg/kg) was added to the oral prednisolone after discharge. In the periodic fever and neutrophilic dermatosis, the rheumatologist should search for sterile abscesses in other organs.