Congenital Juvenile Xanthogranuloma in the Perioral Region: A Case Image.

Juvenile xanthogranuloma (JXG) is the most common form of non-Langerhans cell histiocytosis in childhood. It often presents with cutaneous involvement and exhibits a predilection for the head and neck region. This article illustrates a case of congenital JXG in a 5-month-old boy, characterized by a solitary, well-circumscribed nodule above the left upper lip. Histopathologically, the lesion exhibited histiocytes with eosinophilic cytoplasm and Touton giant cells. Immunohistochemistry revealed histiocytes positive for CD68 and Factor XIIIa, while negative for S-100 protein. Clinicians should become familiar with the broad clinical spectrum of cutaneous JXG, particularly its congenital presentation, in order to ensure timely and accurate management.

A rare presentation of Rosai-Dorfman-Destombes disease with central nervous system involvement and cutaneous wounds.

OBJECTIVE: The aim of this case report is to investigate an uncommon presentation of Rosai-Dorfman-Destombes (RDD) disease, and discuss possible differential diagnoses and treatment options for this pathology. RDD is a rare disorder of histiocytes that typically presents in patients as painless cervical lymphadenopathy. However, this case involves a patient with the central nervous system (CNS) type of RDD who later developed cutaneous lesions. METHOD: Several differential diagnoses were examined, including hidradenitis suppurativa, pilonidal cyst and pressure ulcers. It is important to be able to exclude these diagnoses based on the presentation, patient demographic and wound location. RESULTS: Biopsies verified the presence of RDD in the patient's suprasellar hypothalamic mass and skin lesions, confirming the patient had both CNS-RDD and cutaneous-RDD in the absence of lymphadenopathy. CONCLUSION: Recognising the unique manifestations of rare diseases such as RDD prevents delay of proper intervention and treatment.

Rosai-Dorfmann Disease: A Rare Disease Presenting as a Unilateral Neck Swelling.

Rosai-Dorfman disease (RDD) is a rare histiocytic proliferative disorder of unknown etiology. Usually it presents with massive painless cervical lymph node enlargement. Histologically, it shows proliferation of distinctive histiocytic cells that demonstrate emperipolesis in the background of a mixed inflammatory infiltrates. Immunohistochemically, the cells are positive for markers such as CD68 and S100. A 14-year-old boy presented with painless right sided cervical lymphadenopathy without any systemic and other ear, nose, and throat manifestations. The biopsy report of the lymph node showed infiltration of sheets of histiocytes showing emperipolesis with areas of fibrosis and hyalinisation. The sinus histiocytes were strongly positive for S-100 protein. RDD must be considered in the differential diagnosis of massive or multiple lymphadenopathies.

Erdheim-Chester disease with tendon and muscle involvement: Reports of a rare presentation.

Erdheim-Chester disease (ECD) is a rare histiocytic disease that affects multiple systems in the body. While it typically targets long bones, cardiovascular structures, the retroperitoneum, and the central nervous system, reports of tendon and skeletal muscle involvement are scarce. This review presents 2 cases: a case of ECD involving the left Achilles tendon and left abductor hallucis, as well as an unusual manifestation of ECD in the thigh musculature. In Case 1, studies involved a 39-year-old man who initially presented with bone and pituitary involvement. An order for 18F-FDG PET/CT imaging was placed by marked swelling in the patient's left ankle and observed soft tissue fullness on foot radiographs, which revealed a soft tissue mass involving the left Achilles tendon, which arose along the tendon-muscle junction and involved the left abductor hallucis muscle. In Case 2, studies involved a 41-year-old man who initially presented with involvement of the cardiovascular system and retroperitoneum. 18F-FDG PET/CT scan showed an infiltrative right atrial mass and hypermetabolic lesion in the left external obturator muscle, extending to the left pectineus and right quadratus femoris muscle. Involvement of the Achilles tendon and skeletal muscle involvement, including left abductor hallucis muscle and medial thigh muscles, is one of the rare manifestations of ECD. Diagnostic delays were frequent due to the condition's rarity and nonspecific multisystemic symptoms. This should be considered in patients who present with myositis, tendinopathy, and bone pain and have other unexplained multisystemic problems.

Rare Case of a Patient With Erdheim-Chester Disease Presenting With Atypical Breast Involvement.

Erdheim-Chester disease (ECD) is a rare multisystem disorder characterized by mitogen-activated protein kinase (MAPK) pathway mutations. Herein, we present a unique case of ECD in a 79-year-old female with predominant breast nodules. Comprehensive imaging and histopathological evaluations confirmed the diagnosis. Mammography and ultrasonography revealed multiple hyperdense circumscribed nodules with coalescing masses and blurred margins. Core biopsy revealed infiltrating foamy cluster of differentiation (CD) 68+ and CD1a+ histiocytes. Because the tumor was negative for the BRAF V600E mutation, treatment with interferon-α was initiated. This case highlights the diagnostic challenges associated with ECD, the rarity of breast involvement, and the importance of considering ECD in the differential diagnosis of atypical breast lesions. Comprehensive imaging, histopathology, and genetic testing are essential for accurate diagnosis and treatment decision-making in ECD. Further research and awareness are required to improve recognition and management of this rare disease.

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.

Recurrent petit mal seizures in Erdheim-Chester disease mimicking an intra-axial brain tumor: illustrative case.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare non-Langerhans cell histiocytosis characterized histologically by foamy histiocytes and Touton giant cells in a background of fibrosis. Bone pain with long bone osteosclerosis is highly specific for ECD. Central nervous system involvement is rare, although dural, hypothalamic, cerebellar, brainstem, and sellar region involvement has been described. OBSERVATIONS: A 59-year-old man with a history of ureteral obstruction, medically managed petit mal seizures, and a left temporal lesion followed with serial magnetic resonance imaging (MRI) presented with worsening seizure control. Repeat MRI identified bilateral amygdala region lesions. Gradual growth of the left temporal lesion over 1 year with increasing seizure frequency prompted resection. A non-Langerhans cell histiocytosis with a BRAF V600E mutation was identified on pathology. Imaging findings demonstrated retroperitoneal fibrosis and long bone osteosclerosis with increased fluorodeoxyglucose uptake that, together with the neuropathologic findings, were diagnostic of ECD. LESSONS: This case of biopsy-proven ECD is unique in that the singular symptom was seizures well controlled with medical management in the presence of similarly located bilateral anterior mesial temporal lobe lesions. Although ECD is rare intracranially, its variable imaging presentation, including the potential to mimic seizure-associated medial temporal lobe tumors, emphasizes the need for a wide differential diagnosis.

Histiocitosi en pediatria: la gran simuladora / Histiocitosis en pediatría: la gran simuladora / Histiocytosis in pediatrics: the great simulator

Fonament. La histiocitosi de cèl·lules de Langerhans (HCL) és una malaltia caracteritzada per l’acumulació anormal decèl·lules del sistema monociticomacrofàgic, amb una presentació clínica molt variable. Sovint, atesa la gran variabilitat clínica d’aquesta entitat, es fan diagnòstics tardansque repercuteixen en el pronòstic.Objectiu. Descriure les principals manifestacions clíniquesde l’histiocitosi de cèl·lules de Langerhans (HCL) en unhospital de tercer nivell els darrers catorze anys. Mètode. Estudi observacional, descriptiu i retrospectiu delscasos d’HCL tractats a l’Hospital Universitari Vall d’Hebron.Criteris d’inclusió: edat dels participants (de 0 dies fins a 18anys), període d’estudi (2006-2021) i diagnòstic de la malaltia, basat en el diagnòstic clínic o la confirmació histològica. Mitjançant la revisió d’històries clíniques es van registrar variables demogràfiques (edat i sexe), clíniques (formade presentació, manifestacions inicials, evolució i recaigudes) i troballes rellevants en les proves complementàries. Resultats. Es van revisar 55 casos diagnosticats d’HCL. Lamitjana d’edat de presentació va ser 4,5 anys (RI 1-8), ambpredomini del sexe masculí (3:1). El motiu de consulta mésfreqüent ha estat l’aparició d’una tumoració (20%, sobretota la zona cranial), seguit per dolor ossi (14,5%), polidípsiai poliúria (9,1%), torticoli (9,1%), coixesa, exantema cutanii febre (7,3% cadascuna). Basant-nos en la classificacióLCH-IV, la majoria es van classificar com a unisistèmiques(71%) enfront de les multisistèmiques (29%). Conclusions. L’HCL és una malaltia poc freqüent en pediatria, però amb un espectre clínic ampli que comportadiagnòstics tardans associats a complicacions. Té molta importància conèixer aquesta entitat i les seves manifestacionsprincipals. (AU)

Fundamento. La histiocitosis de células de Langerhans (HCL) es una enfermedad caracterizada por la acumulación anormal de células del sistema monocítico-macrofágico, con una presentación clínica muy variable. A menudo, dada la gran variabilidad clínica de esta entidad, se realizan diagnósticos tardíos que repercuten ensu pronóstico. Objetivo. Describir las principales manifestaciones clínicas de la histiocitosis de células de Langerhans (HCL) en un hospital de tercer nivel en los últimos 14 años. Método. Estudio observacional, descriptivo y retrospectivo de los casos de HCL tratados en el Hospital Universitario Vall d’Hebron. Criterios de inclusión: edad de los participantes (de 0 días de vida hasta 18 años), período de estudio (2006-2021) y diagnóstico dela enfermedad, basado en el diagnóstico clínico o la confirmación histológica. Mediante la revisión de historias clínicas, se registraron variables demográficas (edad y sexo), clínicas (forma de presentación, manifestaciones iniciales, evolución y recaídas) y hallazgos relevantes en las pruebas complementarias. Resultados. Se revisaron 55 casos diagnosticados de HCL. La media de edad de presentación fue 4,5 años (RI 1-8), con predominio del sexo masculino (3:1). El motivo de consulta más frecuente ha sido la aparición de una tumoración (20%, sobre todo a nivel craneal), seguido por dolor óseo (14,5%), polidipsia y poliuria(9,1%), tortícolis (9,1%), cojera, exantema cutáneo y fiebre(7,3% cada una). Basándonos en la clasificación LCH-IV, la mayor parte se clasificaron como unisistémicas (71%) frente a las multisistémicas (29%). Conclusiones. La HCL es una enfermedad poco frecuente en pediatría pero con un amplio espectro clínico que comporta diagnósticos tardíos asociados a complicaciones. Resulta de gran importancia conocer a esta entidad y sus principales manifestaciones. (AU)

Background. Langerhans cell histiocytosis (LCH) is a disease characterized by the abnormal accumulation of cells of the monocytemacrophage system. Its clinical presentation is highly variable, which can lead to late diagnosis and worse outcomes.Objective. To describe the main clinical manifestations of LCH in atertiary hospital in the last 14 years. Method. Observational, descriptive, and retrospective study of children with LCH treated at the Hospital Universitari Vall d’Hebron.Inclusion criteria: age of the participants (0 days of life and up to18 years), study period (2006-2021) and diagnosis of the diseasebased on clinical diagnosis or histological confirmation. We recorded demographic variables (age and sex), clinical characteristics(form of presentation, initial manifestations, evolution, and relapses), and relevant findings in diagnostic tests. Results. 55 children diagnosed with LCH were reviewed. The meanage at presentation was 4.5 years (IR 1-8), with a predominanceof males (3:1). The most frequent reason for consultation was the appearance of a lump (20%, especially at the cranial level), followed by bone pain (14.5%), polydipsia and polyuria (9.1%), torticollis (9.1%), and limping, skin rash, and fever (7.3% each). Based on the LCH-IV classification, most were classified as singlesystem (71%) versus multi-system (29%). Conclusions. LCH is a rare disease in pediatrics but with a wideclinical spectrum that can lead to late diagnoses and subsequentcomplications. It is of great importance to know this entity and itsmain manifestations. (AU)

Multicentric Reticulohistiocytosis-A rare and disabling disease.

Multicentric reticulohistiocytosis is a rare multisystemic condition associated with papulonodular skin lesions, severe arthritis and malignancy. Histopathology shows histiocytes containing abundant eosinophilic ground glass cytoplasm and multinucleated giant cells. Early recognition, age-appropriate malignancy work-up and treatment is important to prevent impairment of daily life activity.

A Case of Rosai-Dorfman Disease Presenting as an Isolated Pleural Plaque.

Rosai-Dorfman disease (RDD) is a rare non-Langerhans histiocytic disorder primarily involving lymph nodes. Extranodal RDD has a heterogenous presentation, and isolated pulmonary involvement is rare. We report the only case of RDD presenting as an isolated pleural mass. Our patient was a 55-year-old female with multiple comorbidities who presented with chest pain. Imaging revealed an enlarging pleural-based lesion. She underwent resection of the pleural mass, showing an atypical histiocytic infiltrate in a prominent background of collagenous fibrosis. Immunohistochemistry shows CD1a-negative and S100-positive atypical histiocytic cells demonstrating emperipolesis, confirming the diagnosis of RDD. She is currently on six-month CT surveillance with no recurrence of the disease. This case highlights the unique pulmonary presentation of RDD. It also underscores that observations may be appropriate in isolated asymptomatic pleural involvement cases.

Rare Cutaneous Manifestations of Erdheim Chester Disease: A Case Report and Literature Review.

Erdheim Chester disease (ECD) is a rare and complex non-Langerhans histiocytic systemic disease that affects multiple organ systems, including the bones, heart, lungs, and central nervous system. Fewer than 1,000 cases have been reported in the medical literature and dermatological manifestations of the disease are rare but can provide valuable diagnostic clues for this challenging disease. The cutaneous manifestations of ECD can take many forms, including nodules, plaques, papules, and xanthomas. These lesions can occur on any part of the body and may be solitary or multiple. Cutaneous manifestations of ECD have been reported to occur in up to 20% of cases, but the true prevalence may be higher, as many cases may go undiagnosed. We present the case of a 62-year-old gentleman with a history of ECD currently on vemurafenib who presented with multiple painless subcutaneous nodules on his back after an excision biopsy under local anesthetic revealed histological features of ECD. The objective of this case report is to raise awareness of ECD and its dermatological manifestations. Further research is warranted to better understand the pathogenesis and morphology of cutaneous involvement in ECD.

Erdheim-Chester disease with bilateral orbital masses and multi-systemic symptoms: two case reports.

BACKGROUND: Erdheim-Chester disease (ECD) is a rare histiocytic disorder characterized by multisystem xanthogranulomatous infiltration by lipid-laden histiocytes. We report two cases of ECD involving the orbit and describe their clinicopathologic factors, treatments, and prognosis. One was a rare case of ECD complicated with primary thrombocytosis. CASE PRESENTATION: This study describes two patients with bilateral orbital ECD. Both presented with proptosis and visual loss; imaging findings showed bilateral intraorbital masses. Both had different degrees of systemic symptoms (pleural effusion, pericardial effusion, ascites, and heart failure) before the ocular symptoms and did not find the cause before ophthalmic tumor resection and pathological biopsy. The diagnosis of ECD was confirmed after pathological biopsy and detection of BRAFV600E mutation. Patient 2 also with primary thrombocytosis and had a CALR mutation as well as the BRAFV600E mutation. Both patients were recommended to receive targeted therapy. Patient 1 refused targeted therapy for financial reasons and was discharged after local radiotherapy only. The patient had no light perception in either eye and no improvement in systemic symptoms. Patient 2 began targeted treatment after diagnosis and reached the discharge criteria 2 weeks later. He is in good condition at present, but unfortunately, his eyesight has not improved because of the irreversible damage to his visual function. CONCLUSION: ECD is easily misdiagnosed and missed because of its rarity and diverse clinical manifestations. Orbital involvement is common in ECD, and surgery is the most frequently employed approach. Despite the surgical resection is not curative, its significance lies in biopsy to establish diagnosis and/or surgical debulking to relieve mass effect, minimizing further impairment of visual function. Targeted therapy is the most effective treatment for patients with a positive BRAF mutation gene. Evaluation of a concomitant myeloid neoplasm is also critical before initiating targeted therapies for refractory ECD.

The value of 18F-FDG PET/CT in the systemic evaluation of patients with Rosai-Dorfman disease: a retrospective study and literature review.

BACKGROUND: Rosai-Dorfman disease (RDD) is a rare form of non-Langerhans cell histiocytic disease. The aim of this study was to review the characteristics of RDD using 18F-FDG PET/CT and determine its efficacy in the disease management. RESULTS: A total of 28 RDD patients underwent 33 18F-FDG PET/CT scans for systematic assessment and follow-up. The common involved sites included the lymph nodes (17, 60.7%), upper respiratory tract (11, 39.3%), and skin (9, 32.1%). Five patients had more lesions detected in PET/CT images than in CT and/or MRI, including inapparent nodules (n = 5) and bone destruction (n = 3). After thorough treatment evaluation using PET/CT, the treatment strategies of 14 patients (14/16, 87.5%) were changed. Five patients underwent PET/CT twice during follow-up and the SUVs were significantly decreased (15.3 ± 3.4 vs. 4.4 ± 1.0, p = 0.02), which demonstrated disease improvement. CONCLUSIONS: 18F-FDG PET/CT contributed to displaying the holistic characteristics of RDD, in particular during initial assessment, treatment strategy adjustment, or efficacy evaluation, and could compensate for some disadvantages of CT and MRI images.

A Case of Multiple Self-Involuting, Mixed Presentation, Giant Congenital Juvenile Xanthogranuloma.

Juvenile xanthogranuloma (JXG) is an uncommon benign skin disorder of infants and young children characterized by dermal proliferation and infiltration of dendrocytes. We present a unique case of giant congenital JXG with a mixed presentation of macules, papules, nodules, and ulcerations in a neonatal male who was observed until the age of 23 months, by which time all lesions had spontaneously self-involuted. Prior to complete resolution, some lesions took the form of pedunculated protrusions. To our knowledge, this is the first of this atypical case to be presented in the literature.

Histiocitosis de Langerhans y panhipopituitarismo en adulto. Reporte de caso

La Histiocitosis de Células de Langerhans (HCL) es una enfermedad poco común caracterizada por la proliferación clonal de células dendríticas inmaduras que infiltran de forma local o difusa a distintos sistemas, y que afecta principalmente a niños. Presentamos el caso de un hombre de 38 años con historia de caída de múltiples piezas dentales de larga data, sin asociación a traumatismo, tabaquismo ni a mala higiene dental. Tomografía Computada (TC) de cráneo que mostró múltiples lesiones líticas mandibulares. El resultado de biopsia mandibular e inmunohistoquímica eran compatibles con el hallazgo de HCL. Durante su evolución, cursa con poliuria, polidipsia y nicturia, confirmando mediante estudio hormonal diabetes insípida y panhipopituitarismo. Resonancia Magnética (RM) cerebral muestra neoplasia hipotalámica con compromiso infundibular e imagen sugerente de granuloma hipofisiario. Se decide defocación maxilobucofacial, suplementación hormonal, junto con quimioterapia y radioterapia. El paciente evolucionó favorablemente.

Langerhans-cells Histiocytosis (LCH) is a rare disease characterized by the clonal proliferation of immature dendritic cells that locally or diffusely infiltrate different systems, mainly affecting children. We present the case of a 38-year-old man with a long-standing history of multiple tooth loss without association with trauma, smoking, or poor dental hygiene. Skull computed tomography (CT) showed multiple lytic jaw lesions. Jaw biopsy and immunohistochemical results were compatible with the finding of LCH. The patient evolved with polyuria, polydipsia, and nocturia, confirming the presence of diabetes insipidus and panhypopituitarism through hormonal studies. Magnetic resonance imaging (MRI) of the brain shows a hypothalamic neoplasm with infundibular involvement and an image suggestive of a pituitary granuloma. The treatment consisted of maxillobuccofacial defocusing, hormonal supplementation, chemotherapy, and radiotherapy with favorable evolution.

A rare case of Rosai-Dorfman disease presenting as a pulmonary artery mass in a 33-year-old female with hypoxia.

Rosai-Dorfman disease (RDD) is a rare form of non-Langerhans histiocytosis. It is often idiopathic in etiology, but has been associated with viral, autoimmune, and malignant disease. Adequate diagnosis of RDD requires a combination of clinical symptoms, radiography, and histology. Most commonly, patients with RDD present with cervical lymphadenopathy. We describe a case of a young female who was initially thought to have a pulmonary embolism at the time of a COVID-19 infection but was noted to have a rare occurrence of RDD presenting as a pulmonary artery mass upon further evaluation of radiology and histology. Though RDD is frequently benign, extranodal involvement can progress to end organ damage and must be recognized appropriately.