Manifestations Of Langerhans Cell Histiocytosis Research Articles

Comprehensive considerations for dermatologists: the application of FDG-PET in evaluating cutaneous lesions in pediatric Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a complex disorder characterized by the clonal proliferation of Langerhans cells, primarily affecting children and adolescents. This condition exhibits a wide spectrum of clinical presentations, necessitating a multidisciplinary approach for diagnosis, treatment, and follow-up. Cutaneous manifestations of LCH are significant, mimicking common dermatoses and posing diagnostic challenges. [18F]Fluorodeoxyglucose-Positron Emission Tomography (FDG-PET) has emerged as an important tool in the evaluation of pediatric LCH, offering insights into disease activity, extent, and therapeutic response. Moreover, FDG-PET provides a non-invasive means to distinguish between active LCH skin lesions and other dermatological conditions with similar clinical appearances, enhancing diagnostic accuracy and aiding in disease monitoring. This educational review summarizes the utility of nuclear imaging techniques, with a focus on PET scans, in the diagnosis and management of cutaneous pediatric LCH. A comprehensive literature search identified seven relevant articles, including retrospective studies and case reports. These studies highlight the efficacy of FDG-PET in localizing active LCH skin lesions, monitoring disease activity, and guiding treatment decisions. FDG-PET represents a valuable imaging modality for dermatologists, oncologists, and pediatricians managing pediatric LCH patients with cutaneous involvement. This non-invasive technique contributes to improved diagnostic accuracy and facilitates early intervention, ultimately enhancing patient care and outcomes.

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.

The value of 18F-FDG PET/CT in Langerhans cell histiocytosis.

To investigate the value of 18F-FDG PET/CT in diagnosis and disease evaluation of Langerhans cell histiocytosis (LCH). A retrospective analysis of 31 patients with LCH confirmed by histopathology was performed. A systematic analysis of the PET/CT imaging manifestations of LCH was performed, recording patients who were treated and receiving PET/CT for efficacy evaluation. In addition, clinical and laboratory data of LCH patients were collected, and the correlation between these data and PET/CT metabolic parameters was initially investigated. Of the 31 patients, thirty had at least 1 PET/CT positive lesions (96.7%), and one had only skin damage without abnormalities on PET/CT. Of 31 patients, fifteen (48.4%) had single system (SS) disease (9 cases with a single site and 6 cases with multiple sites) and 16 (51.6%) had multisystem (MS) disease (6 low risk and 10 high risk cases). The incidence of LCH lesions in the bone, lymphatic system, pituitary gland, liver, soft tissue, thyroid gland, thymus, and lungs was 20 cases (64.5%), 12 cases (38.7%), 3 cases (9.7%), 2 cases (6.5%), 2 cases (6.5%), 1 case (3.2%), 1 case (3.2%), and 8 cases (25.8%), respectively. A total of 21 PET/CT follow-up scanning were performed in 13 patients receiving chemotherapy, with 13 (61.9%) partial metabolic remission (PMR), 6 (28.6%) progressive metabolic disease (PMD), and 2 (9.5%) stable metabolic disease (SMD), according to PET Response Evaluation Criteria in Solid Tumors (PRECIST) 1.0. Erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) and Lactic Dehydrogenase (LDH) were positively correlated with TTLG (total TLG) (R2 = 0.3256, 0.2409, 0.4205, P < 0.05). The Re-examine SUVmax is positively correlated with re-examine LDH (R2 = 0.7285, P < 0.05). 18F-FDG PET/CT is an effective way to diagnose and evaluate LCH. PET metabolic parameters were associated with laboratory inflammatory markers, suggesting that 18F-FDG PET/CT may be helpful in evaluating disease activity of LCH.

Langerhans cell histiocytosis oral lesions in pediatric patients.

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. 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. 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. 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.

Back pain as a manifestation of Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is a neoplastic histiocytic disorder characterized by a broad spectrum of clinical manifestations, ranging from single organ lesions to a multi-systemic disease. Even though it is more common during the childhood, the incidence in adults is less defined and it may be misdiagnosed due to its clinical heterogeneity [1]. Main sites involved are bones (skull, vertebral bodies), lungs (typically in adult smokers) and skin (common in children). It is also important to assess the involvement of risk organs (liver, spleen or haemopoietic system) to determinate the severity of the diseas [2]. The definitive diagnosis requires a confirmation through histological and immunochemistry examinations, and molecular tests are also recommended to identify BRAF mutations and to estimate the prognosis and decide between different treatment strategies [3].

Spontaneous remission of skull Langerhans cell histiocytosis that had developed by repeated head injury: illustrative case.

Langerhans cell histiocytosis (LCH) was previously characterized as the proliferation of Langerhans-type histiocytes with a wide range of clinical presentations that arise mostly in children. The typical presentation is a gradually enlarging, painless skull mass. Rapid clinical deterioration is rare. A 3-year-old boy who had incurred a right frontal impact head injury demonstrated no apparent neurological deficits. He subsequently bruised the same region multiple times. The right frontal swelling gradually increased over the course of 6 days after the initial injury. Skull radiography showed no bony lesion. The same site enlarged markedly 12 days after the initial injury. Magnetic resonance imaging revealed a frontal bony tumorous lesion associated with multiple subcutaneous cystic mass lesions. The patient underwent open biopsy of the skull lesion and evacuation of the subcutaneous lesions. Histopathological examination confirmed the diagnosis of LCH. Immunohistochemical evaluation revealed positivity for CD1a and langerin and no immunopositivity for BRAF V600E. The skull lesion spontaneously disappeared 30 days after the biopsy without recurrence. Physicians should be aware of this rare clinical manifestation of LCH that developed by a repeat head injury.

Langerhans cell hystiocytosis mimicking necrotizing ulcerative periodontitis - A case report

Langerhans cell histiocytosis (LCH) is a rare disease characterized by abnormal proliferation of bone marrow derived histiocytes followed by their deposition in tissues elsewhere in the body causing damage. Oral manifestations of LCH can sometimes be the only presenting symptoms or the first sign of a disseminated disease. Ulcerated lesions of oral mucosa are one of the common clinical manifestations and can help in early diagnosis of the disease when presented. Since the clinical features mimics several other diseases of oral and maxillofacial region it can be misdiagnosed easily as other pathologies. This article highlights the clinicopathological features of a case of LCH in an elderly patient who has reported to our outpatient department.

Лангергансоклітинний гістіоцитоз у дитини з мультисистемним ураженням, інфікованої поліомієлітом та SARS-CoV-2: особливості діагностики та перебігу хвороби. Клінічний випадок

Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells. The prognosis varies depending on the form of the disease and organ damage. Any organs and systems can be involved in the pathological process in various combinations. A poor response to standard therapy and an unfavorable prognosis are characteristic of patients with a multisystem form of LCH and involvement of organs at risk. Skin lesions are a classic sign of LCH. Purpose - to describe the complexity and duration of diagnosis of LCH with multisystem damage in a boy aged 2 years and 2 months, infected with poliomyelitis and coronavirus. Clinical case. The first clinical manifestations of LCH in the child debuted with an eczematous-seborrheic rash on the scalp with spread to the limbs and trunk. The child was treated for toxicoderma, hemorrhagic vasculitis at the place of residence for 6 months. The boy lost 1.5 kg of body weight in 1 month. At the time of hospitalization, seborrheic-eczematous rashes on the skin with a hemorrhagic component, trophic-inflammatory changes in the nails of the hands, signs of protein-energy deficiency, stomatitis, gingivitis, hepatosplenomegaly, polyserositis, diabetes insipidus, osteolytic foci of the frontal bones were found. Results of the tests: anemia, thrombocytopenia, hypoproteinemia and hypoalbuminemia, coagulation disorders. The patient had the onset of lower flaccid paraparesis, muscle hypotonia. The boy was diagnosed with a number of infectious complications, including poliomyelitis (a derivative of vaccine poliovirus type 2), COVID-19. The child received LCH-III cytostatic therapy with a positive effect. The research was carried out in accordance with the principles of the Helsinki Declaration. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.

Atypical presentation of langerhans cell histiocytosis of temporal bone in a toddler

Ever since Langerhans cell histiocytosis (LCH) was first described in 1865, mystery revolving around its cause and pathogenesis remains, although most agree that LCH is either a reactive or neoplastic process. We aim to highlight the importance of careful investigations of common presentation, which may lead to the diagnosis and treatment in a toddler. We report a case of LCH of the temporal bone with an atypical presentation in a toddler, which led to delayed diagnosis. The patient presented with a vague preauricular swelling and aural polyp. Imaging and histopathological examination of the biopsy revealed temporal bone LCH, and the child was referred to the pediatric oncology unit and successfully treated. This case clearly demonstrates the highly diversified clinical manifestation of LCH and the high level of suspicion required to diagnose it. We describe the challenge faced in managing this rare entity.

Diagnosis, treatment and recurrence of a mandibular Langerhans cell histiocytosis: a three-year follow-up case report

Introduction: Langerhans cell histiocytosis (LCH) is an abnormal clonal proliferation of Langerhans cells secondary to immune process, mutation of oncogene or genetic predispositions. It preferentially affects bone, lung and skin. The incidence is 2–6 cases per million per year. Prognosis is variable and depends on number and location of lesions, and impact of the initial treatment. Oral lesions may be the first sign of LCH as illustrated by the present case. Observation: A 24-year-old male consulted first for severe gingival inflammation, teeth mobilities and alveolar bone loss with a suspicion of LCH. A pulmonary involvement was secondarily revealed by tomodensitometry. Histological examination, from gingival biopsy, confirmed the diagnostic of LCH, showing cells positive for the anti-CD1A antibody. The patient was managed by oral surgery and chemotherapy approaches. Alveolar bone loss significantly reduced. But 2 years and a half after the diagnosis, a recurrence was noted and managed by surgical approach. After a three-year follow-up, no recurrence was noted. Conclusion: Oral lesions can be inaugural manifestations of LCH. The dentist has an essential role in the early detection of these lesions.

Otologic Manifestations of Langerhans Cell Histiocytosis: A Systematic Review

To perform a systematic review to investigate common otologic manifestations of Langerhans cell histiocytosis, the incidence of these findings, methods for diagnosis, as well as medical and surgical management. PubMed/MEDLINE, Embase, and Cochrane Library. A search of PubMed/MEDLINE, Embase, and Cochrane Library for all articles published between 1963 to 2020 was performed with variations and combinations of the following search terms: Langerhans cell histiocytosis, eosinophilic granuloma, Letterer-Siwe, Hand-Schüller-Christian, otitis, otologic, ear. A review of the references of all included articles was also conducted. Sixty-two articles encompassing 631 patients met inclusion criteria. Otologic symptoms at presentation were found in 246 (39%) patients in the reported studies with 48% reporting bilaterality. The mean age was 14.8 years with a male predominance (64%). The most common otologic presenting symptom was otorrhea (46%). A majority had the multisystem variant (52%). The most common treatment modalities were chemotherapy (52%), followed by surgery (50%), systemic steroids (45%), and radiotherapy (31%). Surgery was performed in 75.8% with unisystem involvement and in 50.6% with multisystem involvement. The most effective treatments included radiotherapy (56% success rate, 17% of treated patients), systemic steroids (44% success, 20% treated), chemotherapy (41% success, 21% treated), and surgical modalities (36% success, 19% treated). Otologic manifestations that occur with the multisystem variant or are at high risk for central nervous system involvement necessitate systemic treatment. For unifocal lesions, surgery is recommended. Lastly, radiotherapy should be reserved for extensive lesions involving vital structures or presenting in older patients.

Clinical manifestations of Langerhans cell histiocytosis with multisystem involvement in 53 children

Objective: To analyze the clinical characteristics and long-term outcome of Langerhans cell histiocytosis with multisystem involvement (MS-LCH) in children, and to evaluate the efficacy of modified DAL-HX83/90 protocol. Methods: This retrospective study included 53 patients with MS-LCH admitted to the Department of Pediatric Hematology and Oncology, First Affiliated Hospital of Zhengzhou University from January 2011 to May 2019. Modified DAL-HX83/90 protocol was used in all patients as an initial treatment. The patients were divided into the group with (RO+) or without (RO-) risk organ involvement. The RO+group was further divided into two groups, as RO+Ⅰ group (lung involvement only) and RO+Ⅱ group (extra-pulmonary, with or without lung involvement). The clinical characteristics and the long-term outcome were summarized. Event-free survival (EFS) and overall survival (OS) curves were analyzed with Kaplan-Meier method. Univariate and multivariate analysis of prognostic factors including age, sex, risk organ involvement and response to 6-week induction were analyzed with Log-Rank test and Cox proportional hazards models. Results: Among the 53 children with MS-LCH, 34 were male and 19 were female. The age of onset was 21 months (3 months-13 years). There 22 were in RO+group, with 12 in RO+Ⅰ group and 10 in RO+Ⅱ group, and 31 in RO-group. The follow-up period was 51 (12-144) months. The overall response rate of 6-week induction was 89% (47/53), and the recurrence rate was 30% (16/53). The 5-year EFS and OS were (67±6) % and (83±5) %, respectively. Univariate analysis showed that the 5-year EFS and OS of patients who responded well to 6-week induction chemotherapy were significantly higher than those who had no response ((76±6) % vs. 0, (88±4) % vs. (41±22) %, χ2 = 34.743, 10.608, both P<0.05). The 5-year EFS and OS of RO-group were significantly higher than that of RO+group ((80±7) % vs. (49±10) %, (93±4) % vs. (70±10) %, χ2=6.022, 4.793, both P<0.05). And the 5-year EFS of RO+Ⅰ group was significantly higher than that of RO+Ⅱ group ((83±10) % vs. (10±9) %, χ2=9.501, P=0.002). While age and sex were not significantly associated with 5-year EFS and OS (all P>0.05). Cox proportional hazard regression model showed that response to 6-week induction chemotherapy was the independent risk factor for EFS (HR=13.114, 95%CI 3.759-45.742, P<0.01) and OS (HR=7.748, 95%CI 1.542-38.920, P=0.013). Conclusions: Most of the children without risk organ involvement treated with modified DAL-HX83/90 protocol could achieve long-term survival. However, the children involved liver, spleen, or hematopoietic system had a high risk of disease progression and recurrence.

Manifestation of Langerhans cell histiocytosis in the oral cavity: The authors’ experience

Abstract Background. Langerhans cell histiocytosis is a rare reactive proliferative disorder marked by excess proliferation and accumulation of mononuclear phagocytes in tissues and organs. Usually, organs and systems where Langerhans cells are normally found are involved. Lesions may be limited to one system and be single- or multisite, or many systems may be involved. The etiology is not fully known. According to one of the hypotheses, immune dysfunction due to exuberant response to an unknown antigen may be the cause. The most common clinical symptoms include skin lesions, bone pain, exophthalmos, and enlarged lymph nodes, affecting the liver and spleen. Gingivitis, pocket granulation tissue, ulceration of the gingival papilla, alveolar bone atrophy leading to loosening and loss of teeth are observed in the oral cavity. The aim of the study was to determine the type and incidence of oral manifestations in patients diagnosed with Langerhans cell histiocytosis. Methods. We evaluated patients’ medical records to obtain data on the children’s age at diagnosis, sex, the form of Langerhans cell histiocytosis, clinical picture (systemic and local oral symptoms), and radiological findings. Dental examinations (clinical and radiological) were performed to assess oral mucosa and periodontal tissues, and medical records were analyzed for the course and treatment of histiocytosis. Results. The analysis included the medical records of 43 patients with Langerhans cell histiocytosis. Oral lesions in the form of gingivitis, pathological tooth mobility, and expansion of alveolar mandibular bone were observed in 7 patients. Conclusions. Langerhans cell histiocytosis may be accompanied by maxillary, gingival, and mucosal lesions.

Langerhans Cell Histiocytosis Presenting with Central Diabetes Insipidus in an Adult: A Case Report with a Discussion on Differential Diagnosis, Diagnostic Work up and Treatment

Langerhans Cell Histiocytosis (LCH) is rare in adults; the condition affects 1-2 patients per million annually in the general population. Diabetes Insipidus (DI) is a common manifestation of Langerhans Cell Histiocytosis (LCH) although its reported frequency varies in different series. The pathogenesis of the condition is not precisely understood. Infiltration of the hypothalamic-pituitary axis by Langerhans-like cells has been reported in 50% of autopsied patients. Central Diabetes Insipidus (CDI) can be familial, idiopathic or secondary and is a disorder characterised by polyuria, polydipsia and formation of hypotonic urine.

Diverse and rare clinical manifestations of Langerhans cell histiocytosis

Diverse and rare clinical manifestations of Langerhans cell histiocytosis

Primary Oro-Facial Manifestations of Langerhans Cell Histiocytosis in Pediatric Age: A Bi-Institutional Retrospective Study on 45 Cases.

Aims: Langerhans Cell Histiocytosis is a rare hematologic disorder usually affecting children and most commonly involving the head and neck region. Primary oro-facial manifestations are rare, and their diagnosis is often challenging as they are numerous and often resemble common pathologies, refractory to conventional medical and/or instrumental treatments. For such reasons, the diagnosis is frequently delayed, as is the following staging and therapy onset. We retrospectively studied 45 pediatric patients affected by Langerhans Cell Histiocytosis with onset in the head and neck, to examine their clinical and radiological features at the early stage. Materials and Methods: The study was a retrospective bi-institutional analysis (Department of Pediatric Dentistry and Pediatric Oncology of “Sapienza” University of Rome, Department of Interdisciplinary Medicine of the University of Bari “Aldo Moro”), which enrolled 45 patients (age range 0–18 year-old) affected by Langerhans Cell Histiocytosis with oro-facial onset. Data regarding clinical appearance, number, site, synchronous or metachronous occurrence, involved tissues/organs, radiographic features and clinical outcomes were collected, listed and overall differentiated by two age ranges (0–10-year-olds and 10–18-year-olds). Results: Patients were 26 males and 19 females, with an average age at the time of diagnosis of 4.8 ± 3.8 years (median = 3.9 years). The most common findings were inflamed, hyperplastic, painful and often ulcerated gingival lesions (22 cases), associated with deciduous tooth mobility and/or dislocation with bone loss in 18 cases, followed by nine single eosinophilic granulomas of the mandible and two of the maxilla. Lesions of the palatal mucosa were observed in six patients; nine patients showed on radiograms the characteristic “floating teeth” appearance in the mandible with synchronous lesions of the maxilla in six. Paresthesia was relatively un-frequent (three cases) and the pathological fracture of the mandible occurred in six. Head/neck lymph nodes involvement was associated with oral lesions in 12 cases and skull lesions in 14. Otitis (media or externa) was detected in four instances, exophthalmia in two, cutaneous rush in nine, contextual presence or subsequent onset of insipidus diabetes in eight. As for therapy, single or multiple small jaw lesions were all surgically removed; chemotherapy with vinblastine alone or associated with corticosteroids was the principal treatment in almost the 80% of cases; more than 50% of patients received corticosteroids, while only three patients received adjunctive radiotherapy. The overall mortality account for less than 9% (four of 45 cases) and recurrence observed in eight patients after therapy. Conclusions: Langerhans Cell Histiocytosis may mimic several oro-facial inflammatory and neoplastic diseases. Considering the potential disabling sequela following head and neck localization of Langerhans Cell Histiocytosis in children, especially at the periodontal tissues with teeth and alveolar bone loss, lesion recognition along with the histological examination of suspicious tissues is mandatory to achieve an early diagnosis and to prevent further organ involvement.

Oral manifestations of Langerhans cell histiocytosis with unusual histomorphologic features

Langerhans cell histiocytosis (LCH) is a bone marrow-derived immature myeloid dendritic cell proliferative disorder with diverse clinical manifestations commonly involves bone, skin, lymph node and lung. Oral involvement is uncommon. Intraoral lesions can be the first sign of either a localized LCH or clinically undiagnosed systemic LCH, predates systemic manifestations of LCH, or an early indicator of recurrence in known cases. Clinically, it can be mistaken for primary oral and dental inflammatory, infectious and neoplastic lesions. Histologically, diagnostic challenges may arise because of the nature of oral and dental specimens, different tissue reaction patterns and variations in histomorphology of LCH. We performed a retrospective review study over 10 years. We searched for diagnosed cases of LCH. We retrieved and reviewed cases of LCH with oral involvement. We found 54 cases of LCH, four (7.4%) with oral involvement. The age range was between 1 and 27 years with an average age of 13.7 years. They were males. They were clinically confused with abscess, cysts, infection, granulation tissue and other neoplastic lesions. Histologically, they showed different histopathologic features including different patterns of necrosis, granulomas, allergic-like inflammation, superimposed infection, stomatitis, cyst and sinus formation, foreign body giant cell reaction, and foci mimicking lymphomas and metastasis. Certain cytologic features were helpful hints. In doubtful cases, immunohistochemistry helped confirm the diagnosis. Because of the multiple fragmented nature of oral specimens with different tissue reaction patterns, the diagnostic Langerhans cells may be missed or misinterpreted. Oral LCH may be confused with infectious, inflammatory, benign and malignant neoplastic lesions because of its variable clinical presentations and its heterogeneous histomorphologic features. Pathologists have an important role in guiding clinicians to the correct diagnosis and patients' management. They should be familiar with the different histomorphologic patterns to avoid pitfalls. Attention to certain morphologic features and immunohistochemistry should help resolve challenging cases.

Reaserch Advance on Langerhans Cell Histiocytosis Review

Abstract Langerhans cell histiocytosis (LCH) is a disease originated from bone marrow dendritic cells, and classified as a tumor by the discovery of a recurrent somatic BRAF-V600E point mutation in the RAS-RAF-MEK-ERK signaling pathway. The clinical manifestations of LCH are mainly granulomatous lesions composed of clonal pathological tissue cells. According to the lesions and invasive risk organs, it is divided into single system diseases, multi-system diseases with risk-free organ infiltration and multi-system diseases with risk organ infiltration. The diagnosis was based on immunohistochemical pathological dendritic cell-specific markers CD1α++and/or CD207+,therefore, according to risk stratification, the regiment and intensity of combination chemotherapy and targeted therapy are drawn up. Prognosis is associates with risk organ infiltration, initial treatment response, and BRAF mutations. Due to the low incidence and lack of systematic knowledge, the clinical understanding of this disease is insufficient, thus the rates of misdiagnosis and therapeutic error are high. In this review, the pathogenesis, clinical manifestations, diagnostic and treatment are summarized. So on to provide a theroretical basis for clinical diagnosis and treatment of the diseases.

Reaserch Advance on Langerhans Cell Histiocytosis Review

Abstract Langerhans cell histiocytosis (LCH) is a disease originated from bone marrow dendritic cells, and classified as a tumor by the discovery of a recurrent somatic BRAF-V600E point mutation in the RAS-RAF-MEK-ERK signaling pathway. The clinical manifestations of LCH are mainly granulomatous lesions composed of clonal pathological tissue cells. According to the lesions and invasive risk organs, it is divided into single system diseases, multi-system diseases with risk-free organ infiltration and multi-system diseases with risk organ infiltration. The diagnosis was based on immunohistochemical pathological dendritic cell-specific markers CD1α++and/or CD207+,therefore, according to risk stratification, the regiment and intensity of combination chemotherapy and targeted therapy are drawn up. Prognosis is associates with risk organ infiltration, initial treatment response, and BRAF mutations. Due to the low incidence and lack of systematic knowledge, the clinical understanding of this disease is insufficient, thus the rates of misdiagnosis and therapeutic error are high. In this review, the pathogenesis, clinical manifestations, diagnostic and treatment are summarized. So on to provide a theroretical basis for clinical diagnosis and treatment of the diseases.

Clinical Manifestations of Adult Langerhans Cell Histiocytosis with Multisystem Involvement Successfully Treated Using Chemotherapy

Abstract Introduction: Langerhans cell histiocytosis (LCH), the most common histiocytic disorder, characterized by the abnormal over production of histiocytes that tend to infiltrate single or multiple organ systems leading to significant tissue damage. Here we report a case of an adult patient who was diagnosed with LCH presenting as multisystem involvement. Case presentation: We describe a 23-year-old man suffering from central diabetes insipidus, "hemorrhoids", progressive hearing loss and a surge in weight. Physical examination revealed lesion involvement of the skin and mucous membranes, including the perianal area, gingiva, and external auditory canal. He was diagnosed as LCH, who achieved remission following a chemotherapy regimen. Discussion: LCH is common in children, but it is not surprising to see it in adults. The clinical manifestations of LCH are highly variable and may involve multiple organs and systems. While, skin involvement is the most obvious symptom, and dermatologists should be familiar with it. Chemotherapy is the first-line treatment for multisystem or multifocal single system adult LCH. Conclusion: Characteristic features of LCH involving the perianal area was described in this case which helped the dermatologist to make quick judgments. We also emphasize that a global concept should be established confronting with a patient with multiple complaints.