Enfermedad de Rosai-Dorfman cutánea, reporte de un caso / Cutaneous Rosai-Dorfman disease, a case report

RESUMEN La enfermedad de Rosai-Dorfman cutánea (ERDC) es una rara proliferación reactiva de histiocitos, que cursa con lesiones cutáneas sin compromiso generalizado. Las manifestaciones clínicas cutáneas son diversas y la variante clínica "tipo tumoración" es la forma más infrecuente. Se describe el caso de un paciente con ERDC que se presentó con esta forma inusual.

ABSTRACT Cutaneous Rosai-Dorfman disease (CRDD) is a rare reactive histiocytic proliferation, which presents with skin lesions without systemic involvement. The clinical cutaneous manifestations are diverse and the "tumor-like" clinical variant is the most infrequent. We describe the case of a patient with CRDD who presented with this unusual form.

Erdheim-Chester disease with chorioretinal and orbital involvement: a case report / Doença de Erdheim-Chester com envolvimento coriorretiniano e orbitário: relato de caso

ABSTRACT A 42-year-old woman presented with bilateral proptosis, chemosis, leg pain, and vision loss. Orbital, chorioretinal, and multi-organ involvement of Erdheim-Chester disease, a rare non-Langerhans histiocytosis, with a negative BRAF mutation was diagnosed based on clinical, radiological, and pathological findings. Interferon-alpha-2a (IFNα-2a) was started, and her clinical condition improved. However, 4 months later, she had vision loss with a history of IFNα-2a cessation. The same therapy was administered, and her clinical condition improved. The Erdheim-Chester disease is a rare chronic histiocytic proliferative disease that requires a multidisciplinary approach and can be fatal if left untreated because of multisystemic involvements.

RESUMO Uma mulher de 42 anos apresentou proptose bi-lateral, quemose, dor nas pernas e perda de visão. Com base em achados clínicos, radiológicos e patológicos, foi diag-nosticada doença de Erdheim-Chester com acometimento orbitário, coriorretiniano e multiorgânico. Trata-se de uma rara histiocitose não Langerhans negativa para a mutação BRAF. Foi iniciado tratamento com interferon alfa-2a (IFNα-2a) e o quadro clínico melhorou. No entanto, quatro meses depois, a paciente apresentou perda visual após a cessação do IFNα-2a. A mesma terapia foi administrada novamente e sua condição clínica melhorou novamente. A doença de Erdheim-Chester é uma doença proliferativa histiocítica crônica rara que necessita de uma abordagem multidisciplinar e pode ser fatal se não tratada, devido a envolvimentos multissistêmicos.

Langerhans cell histiocytosis oral lesions in pediatric patients / Lesiones bucales de Histiocitosis de Células de Langerhans en pacientes pediátricos

ABSTRACT Langerhans cell histiocytosis (LCH) is a disease with unknown etiology. It presents as single-system (affecting a single organ or tissue) or as multisystem (with or without risk organ involvement). The oral cavity may be involved or be the site of the first manifestation Aim To describe, group, and determine the frequency of oral lesions in pediatric patients with LCH, and to relate these lesions to age and the different disease subtypes Materials and Method Clinical and radiographic examinations were used to evaluate 95 patients diagnosed with LCH, aged 0 to 16 years, who were referred to the Department of Comprehensive Pediatric Dentistry at the School of Dentistry, University of Buenos Aires. Clinical histories were prepared and informed consents obtained. Lesions were diagnosed by observation, palpation and biopsies, and grouped according to affected tissues into bone, mucosal, and bone-mucosal Results 42.1% presented oral lesions, and in 14.73%, these lesions were the first manifestation of LCH. Ninety percent presented only bone lesions, while the remaining 10% presented bone-mucosal and mucosal lesions. In the single-system subtype, 52.5% presented bone lesions. In the multisystem subtypes (with or without risk organs), all three types of lesions were found. The association between age at which LCH was diagnosed and oral tissue involvement showed that bone-mucosal lesions occur in young children (average age 1.4 years) diagnosed with multisystem LCH. Oral mucosa was only affected in reactivations of the disease Conclusions A high frequency of oral lesions was observed, which were sometimes the first manifestation of the disease, most often affecting bone tissue. Dentists can play an active role in the initial diagnosis of the disease.

RESUMEN La Histiocitosis de células de Langerhans (LCH) (Langerhans cell histiocytosis) es una enfermedad de etiología aún desconocida. Se presenta en forma unisistémica (afecta un solo órgano o tejido) o multisistémica (con o sin órganos de riesgo afectados). La cavidad bucal puede estar comprometida o ser el sitio de la primera manifestación Objetivo describir, agrupar y determinar la frecuencia de las lesiones bucales de pacientes pediátricos con LCH, relacionarlas con la edad y los diferentes subtipos de la enfermedad Materiales y Método se evaluaron mediante exámenes clínicos y radiográficos 95 pacientes entre 0 y 16 años con diagnóstico de LCH, derivados a la Cátedra de Odontología Integral Niños, Facultad de Odontología, Universidad de Buenos Aires. Se confeccionaron historias clínicas y se obtuvieron los consentimientos informados. Las lesiones fueron diagnosticadas a través de observación, palpación y biopsias, y se agruparon según los tejidos afectados en óseo, mucoso y óseo-mucoso Resultados el 42.1% presentó lesiones bucales y en el 14.73% estas fueron la primera manifestación de LCH. El 90% mostró solo lesiones óseas, mientras que en el 10 % restante se observaron lesiones óseo-mucosas y mucosas. En el subtipo unisistémico el 52.5% presentó lesiones óseas. En los subtipos multisistémicos, "con" o "sin" órganos de riesgo, se hallaron los tres tipos de lesiones. La relación entre la edad de diagnóstico de LCH y el compromiso de tejidos bucales evidenció que las lesiones óseo-mucosas ocurren en niños pequeños (edad promedio 1.4 años) con diagnóstico de LCH multisistémica. La mucosa bucal solo se vio afectada en las reactivaciones de la enfermedad Conclusiones Se observó una alta frecuencia de lesiones bucales, siendo en ocasiones la primera manifestación de la enfermedad, afectando con mayor frecuencia al tejido óseo. El odontólogo puede desempeñar un rol activo en el diagnóstico inicial de la enfermedad.

Presentación clínica de patologías no malignas que simulan leucemia cutis: a propósito de dos casos / Clinical presentation of non-malignant diseases mimicking leukemia cutis: A report of two cases

La infiltración cutánea por células leucémicas conocida como leucemia cutis es una presentación infrecuente de esta patología y constituye un desafío diagnóstico. Los diagnósticos como infecciones, otras patologías neoplásicas con afectación cutánea y los trastornos histiocíticos, entre otros, constituyen los principales diagnósticos diferenciales, ya que configuran un escenario pronóstico y terapéutico diferente. Se presentan dos pacientes que fueron diagnosticados inicialmente como leucemia cutis, cuyo diagnóstico final fue de patologías no malignas.

The infiltration of leukemia cells into the skin, known as leukemia cutis, is a rare presentation of this disease and accounts for a diagnostic challenge. The main differential diagnoses include infections, other neoplastic diseases with skin involvement and histiocytic disorders, among others, as they entail different prognostic and therapeutic approaches. Here we describe two patients who were initially diagnosed with leukemia cutis, whose final diagnosis was of non-malignant diseases.

Crystal storing histiocytosis forming a mass lesion in temporal lobe

Crystal storing histiocytosis is a disorder characterized by local or diffuse infiltration of histiocytes containing crystalline inclusions. This entity has been reported in several organs, however the involvement of the central nervous system (CNS) is extremely rare and to date only 7 cases of crystal storing histiocytosis (CSH) of CNS have been reported in the English literature. More than 90% patients with CSH had an underlying lymphoproliferative or plasma cell disorders, especially multiple myeloma, lymphoplasmacytic lymphoma or monoclonal gammopathy. Radiologically and intraoperatively, CSH may mimic an infectious process or neoplasm, hence its histopathological confirmation is important to facilitate appropriate treatment. In this report, we describe an additional case of crystal storing histiocytosis in a 48 year old female who presented with a mass lesion in the right temporal lobe of the cerebrum.

Are breath-holding spells always innocuous: A case report

The diverse clinical manifestations of Langerhans cell histiocytosis (LCH) present a dilemma to clinicians and pediatricians play an important role in its diagnosis and multidisciplinary approach. LCH, previously known as histiocytosis X, is an uncommon hematological disorder characterized by uncontrolled stimulation and proliferation of normal antigen-presenting cells, Langerhans cells. The purpose of this report is to describe the case of a 7-month-old female child with multisystem involvement who presented with breath-holding spells and to discuss the clinical, radiological, and histopathological features of LCH.

Early response to chemotherapy in children with Langerhans cell histiocytosis predicts long-term disease-free survival

Background: Langerhans cell histiocytosis (LCH) is a rare clonal malignancy of the monocyte-macrophage system. Patients with lesions in 搑isk organs� have significantly higher risk of mortality than patients with lesions limited to 搉on-risk� sites. The influence of early response to therapy on long-term survival in this heterogeneous multi-system disease was analyzed. Methods: During a 7-year period, we retrospectively analyzed the findings in 24 consecutive patients who required systemic chemotherapy for LCH [single system with multifocal bone involvement and multisystem involvement with or without risk organ (RO) involvement]. All patients were started on vinblastine and prednisolone. Progressive disease was treated with salvage protocols or targeted therapy. Positron emission tomography-computed tomography (PET-CT)/conventional CT based response assessment was performed at week 6 of chemotherapy, and if needed after week 12 of chemotherapy. Results: MFO bone, MS ROneg, and MS ROpos LCH was observed in 3, 4, and 17 patients, respectively. Age range of patients varied from 1 month�years (median = 18 months). The EFS and OS were 100% and 100% for MFO bone, 50% and 100%, respectively, for MS ROneg and 35% and 52%, respectively, for MS ROpos. OS was 93% and 100% for CR attained at 6 and 12 weeks respectively regardless of the risk status (P < 0.01). Conclusion: Rapid early response, that is, complete remission at 6 and 12 weeks was associated with significantly improved overall survival. In slow responders, early salvage with alternative regimens or targeted therapy may result in better outcomes

Síndrome hemofagocítico asociado a varicela / Hemofagocytic syndrome associated with varicella

Presentación del caso. Lactante femenina de 14 meses de edad con desarrollo psicomotor normal, sin comórbidos. Con historia de un día de fiebre de 40 °C, intermitente, acompañada de evacuaciones diarreicas y vómitos. Fue llevada por sus padres a una clínica privada sin notar mejoría con el tratamiento médico indicado. Posteriormente, presentó deterioro clínico y fue llevada a un hospital, donde se diagnosticó un síndrome febril agudo, diarrea con deshidratación leve y faringitis. Al cuarto día de evolución inició con máculas y pápulas que progresaron a vesículas y costras. Además, presentó intolerancia a la vía oral, disnea, distensión abdominal, coma y desequilibrio hidroelectrolítico. Intervención terapéutica. Inició el tratamiento con hidratación parenteral, antivirales, esteroides endovenosos y antihistamínicos; se diagnosticó shock séptico con compromiso respiratorio, se proporcionó ventilación mecánica asistida y fue referida al hospital de tercer nivel para atención por medicina crítica. Los estudios reportaron un derrame pleural derecho del 40 % y hepatomegalia. Continuó el tratamiento con antibiótico terapia, hidratación parenteral, antivirales, diuréticos, antipiréticos y hemoderivados, presentó mejoría, continuó el manejo terapéutico. Evolución clínica. El día 18 presentó fiebre, hepatoesplenomegalia, los exámenes reportaron elevación de ferritina, triglicéridos y citopenia se diagnosticó un síndrome hemofagocítico que evolucionó con una falla multisistémica y falleció al siguiente día

Case presentation. A 14-month-old female infant with normal psychomotor development, without comorbidities. With a one-day history of fever of 40 °C, intermittent, accompanied by diarrhea and vomiting. She was taken by her parents to a private clinic without improvement with the indicated medical treatment. Subsequently, she presented clinical deterioration and was taken to a hospital, where she was diagnosed with acute febrile syndrome, diarrhea with mild dehydration, and pharyngitis. On the fourth day of evolution, she started with macules and papules that progressed to vesicles and crusts. In addition, she presented oral intolerance, dyspnea, abdominal distension, coma, and hydro electrolytic imbalance. Therapeutic intervention. She started treatment with parenteral hydration, antivirals, intravenous steroids, and antihistamines; septic shock with respiratory distress was diagnosed, assisted mechanical ventilation was provided, and she was referred to a tertiary hospital for critical care medicine. Studies reported a 40 % right pleural effusion and hepatomegaly. She continued treatment with antibiotic therapy, parenteral hydration, antivirals, diuretics, antipyretics, and hemoderivatives, presented improvement, and continued therapeutic management. Clinical evolution. On day 18 he presented fever and hepatosplenomegaly. Tests reported elevated ferritin, triglycerides, and cytopenia, and was diagnosed with hemophagocytic syndrome that evolved with multisystemic failure and died the following day

Enfermedad de Rosai-Dorfman intracraneal: un infrecuente diagnóstico diferencial del meningioma. Reporte de un caso ilustrativo

La Enfermedad de Rosai-Dorfman es un trastorno infrecuente y de etiología desconocida. La presentación intracraneal es aún más rara y suele imitar la apariencia de un meningioma en las imágenes del encéfalo. Se presenta el caso de un paciente varón de 38 años que ingresa por una tumoración intracraneal, extra-axial y supratentorial asociada a déficit neurológico leve; con diagnóstico presuntivo de meningioma de la convexidad. Después de la intervención quirúrgica, el diagnóstico histológico definitivo fue de Enfermedad de Rosai-Dorfman intracraneal. Se debe considerar la Enfermedad de Rosai-Dorfman intracraneal dentro del diagnóstico diferencial de una lesión intracraneal extra-axial sugestiva de un meningioma debido a la similitud en las neuroimágenes y la presentación clínica entre ambas patologías.

Rosai-Dorfman disease is an infrequent condition with no known etiology. The intracranial presentation is even rarer, and it resembles the appearance of a meningioma in image studies. We present the case of a 38-year-old male patient who was admitted because of an extra-axial supratentorial cranial tumor, associated to mild neurological deficit. The presumptive diagnosis was convexity meningioma. After surgery, the definitive histologic diagnosis was intracranial Rosai-Dorfman disease. This condition should be considered in the differential diagnosis of an extra-axial intracranial lesion suggesting meningioma, because of similar neuroimaging results and the similar clinical picture.

Progress in the diagnosis and treatment of ocular histiocytosis / 国际眼科杂志(Guoji Yanke Zazhi)

Ocular histiocytosis is a rare and heterogeneous group of disorders which can occur in children and adults. There is a great challenge in the diagnosis and treatment because of the atypical clinical and imaging manifestations. With insights into molecular mechanism of histiocytosis, the discovery of BRAFV600E mutations has changed the understanding of this disease and enabled targeted therapies in most patients. The gold standard of diagnosis has developed into histopathological biopsy combined with the testing for mutations. Surgery is not the only treatment for ocular histiocytosis and targeted therapy has become an effective treatment for patients with mutations in MAPK-ERK signal-regulated kinase pathway. However, the greatest challenge for ocular histiocytosis is establishing the early and correct diagnosis due to the diverse types and clinical manifestations. Therefore, this article reviews recent progress in diagnosing and treating ocular histiocytosis, summarizes their clinical and pathological features, and aims to improve the level of diagnosis and treatment among clinicians.

The evaluation of IgG4 and IgG expression in cutaneous Rosai-Dorfman disease

Abstract Objective The authors investigated the expression of IgG4 and IgG in cutaneous Rosai-Dorfman Disease (CRDD) to further improve the understanding of this disease. Methods The authors retrospectively reviewed the clinicopathological features of 23 CRDD patients. The authors diagnosed CRDD by the presence of emperipolesis and immunohistochemical (IHC) staining of histiocytes consisting of S-100(+)/CD68(+)/CD1a(-) cells. The expressions of IgG and IgG4 in cutaneous specimens were assessed by IHC (EnVision) and quantitatively calculated by a medical image analysis system. Results All 23 patients, including 14 males and 9 females, were confirmed to have CRDD. Their ages ranged from 17 to 68 years (mean 47.91 ± 14.16). The most frequently affected skin regions were the face, followed by the trunk, ears, neck, limbs, and genitals. In 16 of these cases, the disease presented as a single lesion. IHC staining of sections showed that IgG was positive (≥ 10 cells/High-Power Field [HPF]) in 22 cases, while IgG4 was positive (≥ 10 cells/HPF) in 18 cases. Moreover, the IgG4/IgG proportion ranged from 1.7% to 85.7% (mean 29.50 ± 24.67%, median 18.4%) in the 18 cases. Study limitations In the majority of studies, as well as in the current study, the design. RDD is a rare disease, so the sample size is small. In the next studies to come, the authors will expand the sample for multi-center verification and in-depth study. Conclusion The positive rates of IgG4 and IgG and the IgG4/IgG ratio assessed through IHC staining may be important in understanding the pathogenesis of CRDD.

Rosai-Dorfman disease of the oral cavity

ABSTRACT First described by J Rosai and R F Dorfman in 1969, Rosai-Dorfman disease (RDD) is a benign, self-limiting histiocytosis of unknown etiology. It is usually seen in the first two decades of life. The most frequent clinical presentation is painless, bilateral cervical lymphadenopathy accompanied by fever, weight loss, and an elevated ESR. However, RDD without nodal involvement is extremely rare, and the most common extranodal location is the head and neck region, mainly affecting the nasal cavity, pharynx, and paranasal sinuses. Oral location of RDD is occasional; according to our knowledge, only 17 cases of oral Rosai-Dorfman disease without lymph node involvement have been found in the literature. Because of the rarity of these isolated oral presentations, the clinical and radiological aspects need to be more studied. This article aims to present a rare case of oral Rosai-Dorfman disease without nodal involvement, detail the clinical and radiological signs, and the treatment strategy used in our patient.

A Case of Senile Langerhans Cell Histiocytosis with Soft Tissue Mass as the Main Manifestation / 罕见病研究

Langerhans cell histiocytosis (LCH) is a rare disease characterized by the proliferation of Langerhans cells and the destruction of local tissue. LCH large occurs in children, whilst incidence of the elderly population is extremely low, and there are few related studies. LCH lesions can involve multiple organs and systems, including bone tissue, lymph nodes, skin, liver, and spleen. However, it is rare that multiple soft tissues are implicated for eldly patients with LCH and present with soft tissue mass as the main manifestation. Here is a report on the clinical features, treatment and prognosis of an elderly LCH with multiple soft tissue masses as the main manifestation, in order to provide clinical reference.

Clinical Characteristics and Diagnostic Experience of Adult Thyroid Langerhans Cell Histiocytosis with Diabetes Insipidus / 罕见病研究

  Objective  To analyze the clinical characteristics of thyroid LCH to enhance understanding of the disease.  Methods  We retrospectively studied the clinical data from six thyroid LCH patients who hospitalized in Huashan Hospital Affiliated to Fudan University from January 2015 to January 2022.We analyzed the ultrasound and 18F FDG-PET/CT imaging characteristics of thyroid LCH.  Results  The six patients diagnosed (2 males and 4 females) were between 18 and 58 years old.All patients had diabetes insipidus.MRI revealed thickened pituitary stalk.Two cases had central hypothyroidism, while four cases euthyroidism.Three cases tested positive for thyroid antibodies.Ultrasound showed thyroid nodules of TI-RADS 3 in three cases, TI-RADS 4 in two cases, and 1 with nodular goiter.Ultrasound showed that all sic cases indicated low echogenicity, 5 of which clear boundaries, 4 of which uneven echo distribution, 5 of which irregular shape, and noen has calcification.18F FDG-PET/CT indicated high uptake nodules with SUVmax values all above 10.4 cases were diagnosed by surgical excision and the other 2 by coarse-needle aspiration biopsy.When diagnosed, two cases had liver and thymus involvement respectively.One case had lung and bone involvement respectively.After treatment, 4 cases showed that nodular goiter shrank, while the other two with liver involvement progressed fast and no assessment made.  Conclusions  Thyroid LCH presented low echogenicity, clear boundaries, irregular shape, without calcification, and high uptake in 18F FDG-PET/CT.A definite diagnosis of pituitary stalk thicking accompanied by thyroid nodules, especially those with hypoechoic and irregular nodules, can be achieved by coarse-needle aspiration biopsy and langerin-specific pathological staining.

The non-communicating intracranial-extracranial Rosai-Dorfman disease: a case report / 中华神经科杂志

Rosai-Dorfman disease (RDD) is a benign self-limited disease characterized by lymphadenopathy and phagocytosis of lymphocytes by histiocytes. A case of intracranial-extracranial non communicating RDD was reported in this paper. The patient was admitted to Shiyan Taihe Hospital in May 2020 because of "the left top scalp tumor was found for 4 months, and the right lower limb was numb for more than half a month". The plain scan and enhanced scan of the patient′s head magnetic resonance imaging (MRI) showed that the disease focus of the left parietal bone was slightly uneven enhanced, its internal and external soft tissues were significantly enhanced, and the local internal and external soft tissues were significantly thickened irregularly, with the size of about 3.2 cm× 4.7 cm, and adjacent brain parenchyma was compressed. After resection of left top mass and intracranial mass, pathological results showed spindle cell proliferation with inflammatory reaction, and immunohistochemical staining results supported the diagnosis of RDD. The neurological function of the patient recovered to normal basically 7 months after operation, and no recurrence of the disease was found in the MRI examination of the head. The treatment effect was satisfactory.

Langerhans Cell Histiocytosis in an Adult Female with Multisystem Involvement

Langerhans cell histiocytosis (LCH) also known as histiocytosis X, is a rare systemic disorder arising from the clonal proliferation of myeloid dendritic cells (histiocytes) with a tendency to involve single or multiple organ systems with variable clinical course and prognosis. Clinical presentation usually depends on the site of involvement. The organs commonly affected in adults by order of decreasing frequency include lungs, bone, skin, pituitary glands, lymph nodes, and the liver. Vulval and perianal involvement is extremely rare in adults. We describe the case of a 31-year-old non-smoker adult female with multisystemic LCH involving the vulva, perianal region, and lung. Probable involvement of other sites with LCH included mandibular bone, pituitary gland, skin, lymph nodes, liver, thyroid, and colon. She is undergoing systemic chemotherapy and has completed two cycles of cytarabine and steroids without any complications. Treatment is not standardized due to the very less incidence of the disease and inadequate knowledge regarding its pathophysiology. Langerhans cell histiocytosis remains a major concern for treating physicians because of its rarity with many faces and requires careful consideration for management.

Oral manifestations of histiocytosis of langerhans cells: a pediatric case involving mandible bone / Manifestaciones orales de histiocitosis de células de Langerhans: un caso pediátrico relacionado con el hueso mandibular

Abstract Langerhans cells histiocytosis is a rare disease characterized by monoclonal proliferation and migration of special dendritic cells in a variety of organs, most commonly appears eosinophilic granuloma localized, often solitary, and bone lesions that occurs predominantly in pediatric patients. Although is most prevalent in children under the age of 15, this disorder presents in all ages and occurs at a rate of 2 to 5 cases per million per year. LCH is a complex entity; the clinic manifestations can mimic other common conditions and therefore a comprehensive evaluation is indicated. Since oral manifestations are frequent, the early diagnose of this pathology could be detected by dental professionals. The aim of this case report is to describe a case of LCH who initially was misdiagnosed and treated for a dental infection. This disease requires accurate histopathological diagnosis and timely treatment; hence it is necessary to raise awareness among dentists to avoid misdiagnose of oral manifestations of LCH.

Resumen La histiocitosis de las células de Langerhans es una enfermedad poco frecuente que se caracteriza por la proliferación monoclonal y la migración de células dendríticas especiales en una variedad de órganos; lo más común es que aparezca un granuloma eosinofílico localizado, a menudo solitario, así como lesiones óseas que se producen predominantemente en pacientes pediátricos. Aunque es más frecuente en los niños menores de 15 años, este trastorno se presenta en todas las edades y se produce a una tasa de 2 a 5 casos por millón al año. La HCL es una entidad compleja; las manifestaciones clínicas pueden imitar otras afecciones comunes y, por lo tanto, se indica una evaluación exhaustiva. Dado que las manifestaciones orales son frecuentes, el diagnóstico precoz de esta patología podría ser detectado por los profesionales de la odontología. El objetivo de este reporte de caso es describir un caso de HCL que inicialmente fue mal diagnosticado y tratado por una infección dental. Esta enfermedad requiere un diagnóstico histopatológico preciso y un tratamiento oportuno; por lo tanto, es necesario sensibilizar a los dentistas para evitar un diagnóstico erróneo de las manifestaciones orales de la HCL.

Histiocitosis de células mixtas: Reporte de un caso

Introducción: Las histiocitosis son enfermedades raras, caracterizadas por la infiltración tisular de histiocitos anormales. Se dividen en cinco grupos. Son frecuentes en la población pediátrica. La combinación de la histiocitosis de células de Langerhans e histiocitosis de células no-Langerhans es fortuita. Reporte de caso: Se reporta el caso de una paciente de 66 años que debutó con un cuadro de compromiso sistémico, del que llamó la atención la presencia de masas tumorales en la cara anterior de las piernas, dolor óseo generalizado y alteraciones endocrinológicas. Se planteó el diagnóstico de histiocitosis mixta. Se sugirió tratamiento con: anticuerpos monoclonales anti BRAF V600E, interferón alfa y/o quimioterapia. Conclusión: Es posible realizar el diagnóstico de histiocitosis a partir de los antecedentes personales patológicos del paciente y los hallazgos clínicos manifiestos con el apoyo de estudios radiológicos, histológicos e inmunohistoquímicos. Finalmente, este es el primer caso de histiocitosis mixta publicado en Ecuador.

Introduction: Histiocytoses are rare diseases characterized by tissue infiltration by abnormal histiocytes. They are divided into five groups. They are frequent in the pediatric population. The combination of Langerhans cell histiocytosis and non-Langerhans cell histiocytosis is fortuitous. Case report: We report the case of a 66-year-old female patient who debuted with a history of systemic involvement, in which the presence of tumor masses on the anterior aspect of the legs, generalized bone pain and endocrinological alterations attracted our attention. The diagnosis of mixed histiocytosis was suggested. Treatment with anti BRAF V600E monoclonal antibodies, interferon alpha and/or chemotherapy was recommended. Conclusion: It is possible to make the diagnosis of histiocytosis based on the patient's personal pathological history and the clinical findings with the support of radiological, histological and immunohistochemical studies. Finally, this is the first case of mixed histiocytosis published in Ecuador.

Tratamiento exitoso de enfermedad de Rosai-Dorfman con inmunomoduladores y quimioterapia metronómica / Successful treatment of Rosai-Dorfman disease with immunomodulators and metronomic chemotherap

RESUMEN Introducción: La enfermedad de Rosai-Dorfman es una histiocitosis linfática masiva caracterizada por emperipolesis con inmunohistoquímica positiva para S100 y CD68. Es una entidad clínica rara y de curso benigno más comúnmente presentada en varones. Objetivo: El propósito de este caso clínico es demostrar el tratamiento exitoso de la enfermedad de Rosai-Dorfman con inmunomoduladores y quimioterapia metronómica. Presentación del caso: Paciente masculino de 57 años que acude por linfadenopatía cervical bilateral, a quien se le realiza tomografía y biopsia ganglionar con resultados positivos para S100 y CD68 con marcado fenómeno de emperipolesis. Recibió esquema inmunomodulador y quimioterapia metronómica exitosa con remisión de enfermedad. Conclusiones: Los pacientes diagnosticados con Rosai-Dorfman son muy pocos debido a lo inusual de esta entidad clínica. Es importante mencionar que esta enfermedad es una histiocitosis de células tipo No Langerhans con características de benignidad y buena respuesta al manejo con corticoides y quimioterapia metronómica, terapia instaurada en nuestro paciente con buena evolución.

ABSTRACT Introduction: Rosai-Dorfman disease is a massive lymphocytic histiocytosis characterized by emperipolesis with positive immunohistochemistry for S100 and CD68. It is a rare clinical entity of benign course most commonly presenting in males. Objective: The purpose of this clinical case is to demonstrate successful treatment of Rosai-Dorfman disease with immunomodulators and metronomic chemotherapy. Case presentation: A 57-year-old male patient presenting with bilateral cervical lymphadenopathy underwent CT scan and lymph node biopsy with positive results for S100 and CD68 with marked emperipolesis phenomenon. He received immunomodulatory scheme and successful metronomic chemotherapy with disease remission. Conclusions: Patients diagnosed with Rosai-Dorfman are very few due to the unusual nature of this clinical entity. It is important to mention that this disease is a non-Langerhans cell histiocytosis with benign characteristics and good response to management with corticosteroids and metronomic chemotherapy, therapy established in our patient with good evolution.

Unusual presentation of Langerhans cell sarcoma as bilateral submandibular gland swelling – A rare case report

Langerhans cell sarcoma (LCS) is a rare malignant tumor of Langerhans cells and uncommonly involves head and neck regions. Unlike Langerhans cell histiocytosis (LCH), it has an aggressive clinical course with malignant cytological features. Till now, a handful of cases have been reported and the common anatomical sites involved are skin, lymph node, and bone in loco – regional cases and lymph node, lung, liver, spleen, and bone in disseminated disease. Due to its rarity, standard protocols of treatment for these patients are not yet well established. Herein, we report such a case in a 25-year-old male presenting with a bilateral submandibular swelling, which was diagnosed as LCH on Fine Needle Aspiration Cytology (FNAC) and later confirmed to be a case of LCS in histopathological examination and immunohistochemistry. The authors are aware of only a single similar case being reported in the English literature.