Multisystemic recurrent Langerhans cell histiocytosis misdiagnosed with chronic inflammation at the first diagnosis: A case report.

BACKGROUND: Langerhans cell histiocytosis (LCH) is characterized by diabetes insipidus and is an uncommon occurrence. Pathological biopsies still have a certain degree of diagnostic probability. We present a case in which LCH initially affected the pituitary gland. This resulted in a misdiagnosis of chronic inflammation upon pathological examination. CASE SUMMARY: A 25-year-old female exhibited symptoms of diabetes insipidus. Magnetic resonance imaging revealed an enhanced foci in the pituitary gland. After surgical resection of the pituitary lesion, the pathological diagnosis was chronic inflammation. However, the patient later experienced bone destruction in the skull and lower limb bones. After the lower limb bone lesion was compared with the initial pituitary lesion, the final diagnosis was modified to LCH. The patient was treated with multiple chemotherapy courses. However, the patient's condition gradually worsened, and she eventually passed away at home. CONCLUSION: LCH should be considered when patients exhibit diabetes insipidus and absence of high signal intensity in the pituitary gland on sagittal T1-weighted image and abnormal enhancement in the pituitary region.

Unusual orbital, scleral and choroidal findings in Erdheim-Chester disease: a case report.

This case report highlights a unique presentation of Erdheim-Chester Disease (ECD) with bilateral scleral lesions, choroidal infiltration, and extensive sinus involvement. It is the first case report where the diagnosis was confirmed through a scleral biopsy after an initial presentation of a unilateral nodular scleritis. There was a gradual disease progression and ocular examination later revealed bilateral subconjunctival hyperemic lesions and mild exophthalmos, ophthalmoplegia, and extensive choroidal infiltration. Infiltration of the frontal and maxillary sinus was present and extended into the nasal cavity and both orbits. The diagnostic work-up is described in detail. Current treatment options are analyzed. It is emphasized that the ophthalmologist can play a crucial role in the diagnosis of ECD, given the substantial prevalence of orbital and ocular symptoms. The overall prognosis for ECD remains unfavorable, particularly in cases with orbital involvement. This case underscores the complexity and importance of a multidisciplinary approach in managing ECD.

Cladribine Use in Xanthoma Disseminatum: A Rare Case Presentation and Brief Updated Literature Review.

Xanthoma disseminatum (XD) is a rare, non-Langerhans cell histiocytosis. While treatment is notoriously difficult, 2-chlorodeoxyadenosine (cladribine) has recently emerged as a potential effective therapeutic option. Here, we describe the case of a 65-year-old male with XD who experienced significant cutaneous improvement after cladribine treatment. We also provide an updated literature review on cladribine use in patients with XD in light of reported adverse effects (AEs). While the efficacy of cladribine in XD is clear, no consensus exists for treatment duration and AE management. Hence, we strongly encourage interdisciplinary discourse involving dermatology and oncology in these cases.

Potential indication of chemotherapy for hypodipsia and arginine vasopressin deficiency secondary to hypothalamic-pituitary Langerhans cell histiocytosis: a case report and literature review.

Hypothalamic-pituitary Langerhans cell histiocytosis (HP-LCH) is often associated with arginine vasopressin deficiency (AVD). Patients with AVD caused by HP-LCH rarely develop an impaired osmotic threshold for thirst (OTT). Improvement in OTT among such patients has not been reported in the literature. To our knowledge, here we report the first case of AVD due to HP-LCH in which hypodipsia resolved during chemotherapy. A nine-year-old Japanese girl presented with polydipsia, polyuria, anorexia, and hypernatremia (149.8 mEq/L) and was diagnosed with AVD secondary to HP-LCH. Visual analog scale examination showed a reduced OTT following the water deprivation test. During chemotherapy for Langerhans cell histiocytosis (LCH), serum sodium concentrations became stable between 138.9 and 142.9 mEq/L under the replacement of desmopressin. Repeated visual analog scale examinations showed that she experienced a sense of thirst at a serum sodium concentration of 142.3-144.6 mEq/L, at which she did not experience any thirst prior to the initiation of chemotherapy. These data suggest that chemotherapy directly improved the OTT in our patient. Improved mechanical compression or infiltration of the hypothalamus related to OTT may lead to the recovery of the sense of thirst. This report highlights the potential role of chemotherapy for solitary HP-LCH in patients with hypodipsia and AVD.

Rosai-Dorfman disease differentiated from a posterior mediastinal tumour: a case report.

Rosai-Dorfman disease presenting solely with intrathoracic lesions is exceptionally rare. Herein, we report the case of a 53-year-old man presenting with a posterior mediastinal tumour. Computed tomography revealed a 7-cm soft tissue shadow in the posterior mediastinum. Positron emission tomography-computed tomography demonstrated a high maximum standardized uptake value of 10.35 in the tumour, with no evidence of lymph node or other organ involvement. Serum marker levels were within the normal range. Thoracoscopic surgery was performed to obtain a biopsy for a definitive diagnosis and treatment planning. Postoperative histological findings revealed a diffuse infiltration of eosinophilic histiocytes, lymphocytes, and plasma cells. Immunohistochemical analysis indicated positivity for S-100 protein, oct-2, and cyclin D1 in these histiocytes. Consequently, the patient was diagnosed with Rosai-Dorfman disease and is currently asymptomatic, undergoing regular monitoring without treatment as an outpatient. The absence of characteristic findings, such as bilateral cervical lymphadenopathy, posed challenges in preoperative diagnosis.

Living-donor lobar lung transplantation for pulmonary Langerhans cell histiocytosis complicated by extensive thrombi in central pulmonary arteries.

BACKGROUND: Pulmonary Langerhans cell histiocytosis (PLCH) is a rare disorder characterized by the proliferation of Langerhans cells along the small airways, which causes nodular and cystic changes in the lung parenchyma. Lung transplantation can be a life-saving option for patients with severe respiratory failure or pulmonary hypertension. Herein, we present a case of successful lung transplantation in a patient with PLCH who developed unusually large thrombi in the central pulmonary artery. CASE PRESENTATION: A 47-year-old woman with 16-year history of PLCH with rapidly developing respiratory failure was admitted to our hospital for the evaluation of a lung transplant. Enhanced computed tomography revealed large thrombi in dilated central pulmonary arteries. Right heart catheterization revealed severe pulmonary hypertension, with a mean pulmonary artery pressure of 48 mmHg. The thrombi shrank markedly after 3 months of anticoagulation therapy. However, the respiratory status of the patient did not improve. We performed bilateral living-donor lobar lung transplantation with thrombectomy under extracorporeal membrane oxygenation for the remaining thrombi in the main pulmonary arteries. The dilated main pulmonary arteries of the recipient required direct plication for size mismatch. The patient survived in good condition for more than 2 years with no recurrence of thrombosis. CONCLUSION: Preoperative anticoagulation therapy for massive thrombi in the pulmonary arteries was effective and led to safe lung transplantation.

A challenging diagnosis of Langerhans' cell histiocytosis with hypothalamic-pituitary and mandibular involvement: case report and literature review.

Background: Langerhans cell histiocytosis (LCH) is a rare bone marrow derived neoplasm that mainly affects children. It is a multiorgan disorder and hypothalamic-pituitary involvement is uncommon. LCH reveals a wide spectrum of indications; thus, the diagnosis and treatment are usually challenging. Case Report: A 22-year-old male presented with polydipsia, polyuria with nonspecific radiological findings, later on, developed a mandibular lesion and a biopsy was conducted which led to LCH diagnosis. After many improper treatments due to unclear diagnosis, the patient was finally placed on chemotherapy and is now under surveillance. Discussion: LCH is a rare disease with diverse clinical manifestations affecting various organs. Associated mutations, such as BRAF V600E, contribute to its complexity. In adults, initial symptoms include pain, weight loss, and fever, with potential pituitary involvement leading to Arginine vasopressin (AVP) deficiency. Commonly affected organs include bone, skin, and the pituitary gland. The disease can be categorized into single-system and multisystem. Pathological diagnosis involves electron microscopy or immunohistochemical staining. Treatment options vary; the presented case utilized Desmopressin acetate and prednisolone before transitioning to cyclophosphamide for multisystemic LCH. Conclusion: AVP deficiency can suggest hypothalamic-pituitary LCH, and a biopsy, if possible, is recommended to confirm the diagnosis.

Rosai-Dorfman Disease as Constrictive Pericarditis: An Unusual Childhood Presentation.

Rosai-Dorfman disease (RDD) is a rare, multisystemic, histiocytic disorder that usually presents with painless cervical lymphadenopathy. We describe a case of constrictive effusive pericarditis with congestive cardiac failure in a six-year-old child as an initial presentation of RDD. The child underwent pericardiectomy and was treated with steroids, following which the symptoms resolved entirely. While tuberculosis accounts for the majority of cases presenting with constrictive pericarditis in developing countries, the presentation of RDD can be easily missed if not kept in mind as a possibility. This case report documents the unique presentation of a rare disease.

[Smoking-related interstitial lung disease : Radiological findings, histopathological correlations, and clinical observations]. / Raucherassoziierte interstitielle Lungenerkrankungen : Radiologisches Erscheinungsbild, histopathologische Korrelation und klinische Aspekte.

CLINICAL/METHODOLOGICAL ISSUE: Identifying smoking-related interstitial lung diseases (SRILD) in smokers is challenging, as clinical manifestations can be nonspecific, and there is a variety of SRILD entities that not only interconnect but can also overlap. RADIOLOGICAL STANDARD PROCEDURES: In diagnosing SRILD, imaging techniques such as high-resolution computed tomography (HRCT) allow the identification of characteristic features, serving as crucial pieces of the puzzle for definitive differentiation. PERFORMANCE: Studies have demonstrated that HRCT exhibits a sensitivity of approximately 80-90% in identifying SRILD, with a specificity around 70-80%. The conclusive diagnosis often requires a correlation between histopathological findings and clinical observations. PRACTICAL RECOMMENDATIONS: Regular monitoring of smokers, especially when experiencing symptoms like shortness of breath and cough, coupled with a comprehensive diagnosis of SRILD, is crucial for accurate identification and individualized therapy.

Histiocytosis and adult-onset orbital xanthogranuloma in 2023: a review of the literature and mini case series.

PURPOSE: Within the large umbrella of histiocytosis are a few similar yet heterogenous entities involving the orbit and periocular tissues with or without systemic infiltration, termed adult onset xanthogranuloma or orbital xanthogranuloma. Due to rarity of these conditions, different classifications in use, diverse clinical presentations and still unknown etiology, the aim of this paper was to provide an up-to-date literature review of the actual understanding of histiocytosis and its subgroups involving the orbit and periocular area, diagnostic strategies and therapeutic modalities. METHODS: We present a review of literature and small case series comprising four patients diagnosed and treated in the period from 2001 until 2023 in our hospital. Clinical files of 4 patients with adult-onset xanthogranulomatous disease of the orbit and ocular adnexa (AOXGD) were reviewed retrospectively. Clinical, laboratory, radiological, histopathological, and immunohistochemical findings were reexamined. RESULTS: Reviewing medical records of our patients with AOXGD, we found significant overlap between histiocytosis and different immune disorders. A broad workup should be considered in these patients as they can harbour severe immune disfunctions and hematologic disorders. Preferred treatment modality depends on a histopathologic type of AOXGD, clinical presentation and systemic involvement and should be conducted multidisciplinary. CONCLUSION: The diagnosis is often delayed because of its rarity and diverse clinical findings. Development of molecular genetic tests, detection of BRAF V600E mutation and different types of kinase mutations, mutations in transcriptional regulatory genes as well as tyrosine kinase receptors have shed a new light on the etiopathogenesis and potential targeted treatment of histiocytosis.

Advancements in the understanding and management of histiocytic neoplasms.

Histiocytic neoplasms are rare diseases involving macrophages, dendritic cells, and monocytes. They include Langerhans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), Rosai-Dorfman disease (RDD), juvenile xanthogranuloma (JXG), and histiocytic sarcoma. Histiocytic neoplasms are characterized by varied clinical courses and prognoses, necessitating a nuanced understanding of their classification, epidemiology, and clinical manifestations. Genetic studies have revealed somatic mutations, predominantly in the MAPK pathway, suggesting a clonal neoplastic nature. This review covers the current understanding of histiocytic neoplasms, molecular pathophysiology, with a particular focus on mutations in genes such as BRAF, MAP2K1, and the PI3K-AKT signaling pathways, and evolving treatment strategies, especially focusing on LCH, ECD, RDD, and JXG. The treatment landscape has evolved with advancements in targeted therapies. BRAF inhibitors, such as vemurafenib and dabrafenib, have shown efficacy, especially in high-risk LCH cases; however, challenges remain, including relapse post-treatment discontinuation, and adverse effects. MEK inhibitors have also demonstrated effectiveness, and cobimetinib has recently been approved for use in adults. Further research is required to determine the optimal treatment duration and strategies for managing therapy interruptions. Advancements in molecular genetics and targeted therapies have revolutionized the management of histiocytic neoplasms. However, ongoing research is crucial for optimizing patient outcomes.

Cranial Rosai-Dorfman disease: a case report and literature review.

Rosai-Dorfman Disease (RDD) is a rare, benign, idiopathic histiocytic proliferative disorder, with its occurrence in the cranial bones being particularly uncommon and prone to misdiagnosis in preoperative radiological examinations. This article reports a case of RDD in the left temporal bone. The radiological presentation of intraosseous RDD includes osteolytic bone destruction, infrequent periosteal reaction, clearly defined tumor margins, and marked uniform enhancement on contrast-enhanced scans. However, these radiological features lack specificity, highlighting the necessity of histopathological examination for a definitive diagnosis, especially for the rarer extranodal subtypes of RDD. Surgical excision of the lesion can lead to favorable therapeutic outcomes.

Clinicopathologic Features of Gastrointestinal Tract Langerhans Cell Histiocytosis.

Gastrointestinal (GI) tract involvement by Langerhans cell histiocytosis (LCH) is rare and its clinicopathologic characteristics have only been described in case reports and small series. We reviewed hematoxylin and eosin- and CD1a, S100, and Langerin immunohistochemical-stained slides from 47 patients with well-documented demographic and clinical findings. Our cases included 8 children and 39 adults, with a mean follow-up of 63 months. All pediatric patients had concurrent multisystem LCH, presented with GI symptoms, and showed non-polypoid lesions. Seven (88%) showed multifocal GI disease, including five with multiple GI organ involvement. All sampled lesions from children exhibited infiltrative growth. More than half had died of the disease or manifested persistent LCH at last follow-up. Twenty-five of 39 (64%) adults had LCH involving only the GI tract (single-system), with the remaining 14 (36%) exhibiting multi-system disease. Adult single-system GI LCH was typically encountered incidentally on screening/surveillance endoscopy (72%). Most exhibited isolated colorectal involvement (88%) as a solitary polyp (92%), with a well-demarcated/noninfiltrative growth pattern (70%), and excellent prognosis (100%). In comparison, adult patients with multi-system LCH more frequently presented with GI symptoms (92%, P<0.001), non-colorectal GI site involvement (50%, P=0.02), multifocal GI lesions (43%, P=0.005), non-polypoid lesions (71%, P<0.001), infiltrative histologic growth pattern (78%, P=0.04), and persistent disease (57%, P<0.001). Adult multi-system LCH patients appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrate that adults with single-system LCH involving the GI tract have an excellent prognosis, while multi-system LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, non-colorectal GI involvement, multifocal GI disease, non-polypoid lesions, and infiltrative growth pattern.

Managing adult-onset Still's disease in pregnancy: A case report.

BACKGROUND: Adult-onset Still's disease (AOSD) is a rare systemic inflammatory disorder characterized by fever, arthritis, skin rash, and systemic symptoms. The etiology of AOSD is unknown; however, it is thought to be related to immune dysregulation. Although a rare disease, AOSD can significantly impact reproductive health, particularly during pregnancy. This case study assesses the implications of pregnancy in a patient with AOSD, as well as the potential for heredity of the disease. Neonatal hemophagocytic lympho-histiocytosis (HLH) is a rare and life-threatening disorder characterized by hyperinflammation and uncontrolled activation of immune cells, leading to multiple organ dysfunction. This case report aimed to introduce neonatal HLH from a mother with AOSD. CASE SUMMARY: This case study presents a 29-year-old female with AOSD who became pregnant and gave birth to a premature infant who was diagnosed with neonatal HLH. AOSD can significantly impact pregnancy and childbirth, as it may become more severe during pregnancy, with an increased risk of fetal loss and preterm birth. The management of AOSD during pregnancy involves the use of nonsteroidal anti-inflammatory drugs and glucocorticoids, as well as immunosuppressive agents in severe cases. However, the use of immunosuppressive agents during pregnancy may be associated with potential risks to the fetus. The hereditary implications of AOSD are unclear; however, available evidence suggests that genetic factors may play a role in the disease development. CONCLUSION: AOSD can have significant implications for pregnancy and childbirth, including an increased risk of fetal loss and preterm birth. Neonatal HLH, a complication of AOSD in pregnancy, requires prompt diagnosis and management. Women with AOSD who are considering pregnancy should discuss their options with their healthcare provider and develop a management plan that addresses the potential risks to both mother and fetus.

Cutaneous Rosai-Dorfman disease: a systematic review and reappraisal of its treatment and prognosis.

Cutaneous Rosai Dorfman disease (CRDD) is a rare histiocytic disorder that shows distinctive clinical presentation and prognosis. Sufficient data is currently lacking regarding evidence-based management of CRDD. This systematic review aims to provide a comprehensive overview of CRDD, focusing on treatment approaches and outcomes. PubMed and Scopus databases were searched for studies on CRDD from June 1st, 2013 to May 31st, 2023. Articles describing cases of CRDD confirmed with histological examination were eligible for inclusion. All interventions for CRDD were analyzed. The primary outcome measure was the response of cutaneous lesions to treatment including complete response (CR), partial response (PR), and no response. The secondary outcome measures were mortality rate, relapse rate, and the occurrence of adverse events related to CRDD treatment. Eighty-seven articles describing 118 CRDD cases were included. The mean age was 48.2±16.8 years. The sex ratio (F/M) was 1.53. Nodular (46.6%) erythematous (45.3%) lesions, located on the face (38.1%) were the most prevalent presentations. Associated hematological malignancies were noted in 8 (6.8%) cases. Surgical excision was the most prevalent intervention (51 cases) with CR in 48 cases. Systemic corticosteroids were used in 32 cases with 20 CR/PR, retinoids in 10 cases with 4 CR/PR, thalidomide in 9 cases with 5 CR/PR, methotrexate in 8 cases with 7 CR/PR while observation was decided in 10 cases with 6 CR/PR. Factors independently associated with the absence of response to treatment were facial involvement (OR = 0.76, p = 0.014), and cutaneous lesion size (OR = 1.016, p = 0.03). This systematic review shows distinctive clinical characteristics of CRDD and provides insights into the appropriate management of the disease. It allowed a proposal of a treatment algorithm that should be interpreted in the context of current evidence and would help practitioners in treating this rare disease.

BRAF-V600E mutations in plasma and peripheral blood mononuclear cells correlate with prognosis of pediatric Langerhans cell histiocytosis treated with first-line therapy.

BACKGROUND: The clinical relevance of BRAF-V600E alleles in peripheral blood mononuclear cells (PBMCs) and the prognostic impact of the mutants in cell-free (cf) and PBMC DNAs of Langerhans cell histiocytosis (LCH) have not been fully clarified in pediatric LCH. METHODS: We retrospectively determined the levels of BRAF-V600E mutation in paired plasma and PBMC samples at the time of diagnosis of LCH. Subsequently, we performed a separate or combined analysis of the clinical and prognostic impact of the mutants. RESULTS: We assessed BRAF-V600E mutation in peripheral blood from 94 patients of childhood LCH. Our data showed that cfBRAF-V600E was related to young age, multiple-system (MS) disease, involvements of organs with high risk, increased risk of relapse, and worse progression-free survival (PFS) of patients. We also observed that the presence of BRAF-V600E in PBMCs at baseline was significantly associated with MS LCH with risk organ involvement, younger age, and disease progression or relapse. The coexisting of plasma(+)/PBMC(+) identified 36.2% of the patients with the worst outcome, and the hazard ratio was more significant than either of the two alone or neither, indicating that combined analysis of the mutation in plasma and PBMCs was more accurate to predict relapse than evaluation of either one. CONCLUSIONS: Concurrent assessment of BRAF-V600E mutation in plasma and PBMCs significantly impacted the prognosis of children with LCH. Further prospective studies with larger cohorts need to validate the results of this study.

Long-term outcome and prognosis of mixed histiocytosis (Erdheim-Chester disease and Langerhans Cell Histiocytosis).

Background: Erdheim-Chester disease (ECD) is a rare histiocytosis that may overlap with Langerhans Cell Histiocytosis (LCH). This "mixed" entity is poorly characterized. We here investigated the clinical phenotype, outcome, and prognostic factors of a large cohort of patients with mixed ECD-LCH. Methods: This retrospective study was performed at two referral centers in France and Italy (Pitié-Salpêtrière Hospital, Paris; Meyer Children's Hospital, Florence). We included children and adults with ECD diagnosed in 2000-2022 who had biopsy-proven LCH, available data on clinical presentation, treatment and outcome, and a minimum follow-up of one year. Outcomes included differences in clinical presentation and survival between mixed ECD-LCH and isolated ECD; we also investigated response to treatments and predictors of survival in the mixed cohort. Survival was analyzed using the Kaplan-Maier method and differences in survival with the long-rank test. Cox regression models were used to evaluate the potential impact of age and gender on survival and to identify predictors of non-response and survival. Findings: Out of a cohort of 502 ECD patients, 69 (14%) had mixed ECD-LCH. Compared to isolated ECD, mixed ECD-LCH occurred more frequently in females (51 vs. 26%, p < 0.001) and in patients with multisystem disease (≥4 sites). Mixed ECD-LCH more frequently involved long bones (91 vs. 79%, p = 0.014), central nervous system (51 vs. 34%, p = 0.007), facial/orbit (52 vs. 38%, p = 0.031), lungs (43 vs. 28%, p = 0.009), hypothalamic/pituitary axis (51 vs. 26%, p < 0.001), skin (61 vs. 29%, p < 0.001), and lymph nodes (15 vs. 7%, p = 0.028); the BRAFV600E mutation was also more frequent in mixed ECD-LCH (81 vs. 59%, p < 0.001). Targeted treatments (BRAF and/or MEK inhibitors) induced response more frequently than conventional therapies (interferon-α, chemotherapy), either as first-line (77 vs. 29%, p < 0.001) or as any line (75 vs. 24%, p < 0.001). After a median follow-up of 71 months, 24 patients (35%) died. Survival probability was comparable between ECD alone and mixed ECD-LCH (log-rank p = 0.948). At multivariable analysis, age at diagnosis (HR 1.052, 95% CI 1.008-1.096), associated hematologic conditions (HR 3.030, 95% CI 1.040-8.827), and treatment failure (HR 9.736, 95% CI 2.919-32.481) were associated with an increased risk of death, while lytic bone lesions with a lower risk (HR 0.116, 95% CI 0.031-0.432). Interpretation: Mixed ECD-LCH is a multisystem disease driven by the BRAFV600E mutation and targeted treatments are effective. Age at diagnosis, bone lesion patterns, associated hematologic conditions, and treatment failure are the main predictors of death in mixed ECD-LCH. Funding: None.

Atypical case of Erdheim-Chester Disease involving bilateral orbits.

Purpose: We report a patient who initially visited the ophthalmology clinic for a vision loss diagnosed with Erdheim-Chester Disease (ECD). Observations: ECD is a rare non-Langerhans cell histiocytosis characterized by multisystemic organ involvement and poor prognosis. Our patient had complete vision loss due to prominent orbital involvement before any systemic symptoms appeared. This case demonstrates variable clinical manifestations of ECD. Conclusions and importance: Painless bilateral proptosis with poor response to steroid treatment should prompt consideration for ECD and systemic evaluation. In addition, in the absence of typical clinical manifestations, a thorough evaluation of the biopsy can be crucial for an accurate diagnosis.