Multisystem Langerhans Cell Histiocytosis Research Articles

Multisystemic Langerhans cell histiocytosis with involvement of skeletal muscles

Multisystemic Langerhans cell histiocytosis with involvement of skeletal muscles

Cladribine in the Treatment of Multifocal Multisystem Langerhans Cell Histiocytosis in a Patient with a Poor Prognosis. A Case Report

Langerhans cell histiocytosis is a hematologic clonal disease. The treatment of localized histiocytosis includes local methods such as radiotherapy or surgery. In cases of disseminated lesions with multiple system damage, chemotherapy is administered, which provides recovery in some patients. The present paper is a case report of multifocal multisystem Langerhans cell histiocytosis with bone, liver, spleen, abdominal lymph node and pituitary lesions in a 40-year-old patient. The diagnosis was verified by histology and immunohistochemistry of bone biopsy specimens. Polymerase chain reaction revealed no V600E mutation in the BRAF gene in tumor tissue. Persistent antitumor response was achieved after 6 chemotherapy cycles with cladribine monoregimen. This drug was well tolerated by the patient. By the time of this publication, the patient had preserved the persistent response for 38 months.

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 nonpolypoid lesions. Seven (88%) showed multifocal GI disease, including 5 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 multisystem 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 multisystem LCH more frequently presented with GI symptoms (92%, P < .001), noncolorectal GI site involvement (50%, P = .02), multifocal GI lesions (43%, P = .005), nonpolypoid lesions (71%, P < .001), infiltrative histologic growth pattern (78%, P = .04), and persistent disease (57%, P < .001). Adult patients with multisystem LCH appear to exhibit similar clinicopathologic features to those of pediatric patients. These results demonstrated that adults with single-system LCH involving the GI tract have an excellent prognosis, whereas multisystem LCH occurring at any age carries an unfavorable prognosis. High-risk features of GI LCH include pediatric age, GI symptomatology, noncolorectal GI involvement, multifocal GI disease, nonpolypoid lesions, and infiltrative growth pattern.

Phase II study in children and adults under 40 years with newly diagnosed Langerhans cell histiocytosis: protocol for an LCH-19-MSMFB clinical trial in Japan

IntroductionAlthough the prognosis of Langerhans cell histiocytosis (LCH) is excellent, the high recurrence rate and permanent consequences, such as central diabetes insipidus and LCH-associated neurodegenerative diseases, remain to be resolved....

Differential Gene Analysis of Langerhans Cell Histiocytosis and the Significance of MMP1-Targeted Drug Repositioning.

Langerhans cell histiocytosis (LCH) is a rare condition predominantly affecting young children. Activation of the MAPK pathway has offered key new insights into the pathogenesis of LCH; however, the precise mechanisms underlying its occurrence and development are still far from being completely elucidated. There is still a relapse/reactivation rate in patients with multisystem LCH. Therefore, this study aimed to investigate other potential LCH pathophysiologies and prospective therapeutic targets. The gene expression omnibus (GEO) database was used to retrieve gene expression profiles of LCH (GSE16395). Three distinct types of analyses were performed after identifying the common differentially expressed genes (DEGs) in LCH: hub gene identification, functional annotation, module construction, drug repositioning, and expression analysis via immunohistochemistry (IHC). We identified 417 common DEGs and 50 central hub genes. This functional study highlighted the significance of keratinization, skin development, and inflammation. In addition, we predicted new drug candidates (RS2 drugs targeting matrix metalloprotease1, MMP1) that could be used for LCH treatment. Finally, gene-miRNA and gene-TF networks and immune cell infiltration were analyzed for MMP1-related genes. MMP1 expression levels in LCH tissues were validated by IHC. Our study identified the central communal genes and novel drug candidates. These shared pathways and hub genes offer new perspectives on future mechanisms of action and therapeutic targets.

A rare case of multisystemic Langerhans cell histiocytosis in an adult affecting the thyroid gland, skeletal system, and pituitary gland: A case report.

Langerhans cell histiocytosis (LCH) is a rare disorder affecting usually children and rarely adults. The most common site affected is bone. The involvement of the thyroid gland in LCH is extremely rare and it is usually observed in an adult as a multisystemic disease. Adult males presented with anterior neck swelling, and fine needle aspiration cytology (FNAC) diagnosed it as suspicious for malignancy. On frozen sectioning, differential diagnosis was given as non-Hodgkin lymphoma and poorly differentiated malignancy. On immunohistochemistry (IHC), tumor cells were positive for CD1a and S100p. Thus, the final diagnosis offered was LCH-thyroid. The pathogenesis is unclear and believed to be related to immune dysfunction, cytokine mediators, viral infection, smoking, and genetic factors. Due to its rarity, thyroid LCH is often misinterpreted as other common disorders of the thyroid and results in delayed diagnosis. This case highlights the importance of histomorphology and the use of ancillary techniques such as IHC to arrive at a diagnosis in time and hence the treatment.

A case of multisystem Langerhans cell histiocytosis with risk organ (liver) and special site (craniofacial) involvement

Langerhans cell histiocytosis (LCH) is a rare clonal proliferative disorder of immature dendritic cells that expresses an immunophenotype positive for S100 protein, CD1a and langerin (CD207) and contains cytoplasmic Birbeck granules. We present a case of multisystem LCH with risk organ (liver) and special site (craniofacial) involvement in a 4-year-old boy who presented with hypopigmented papulopustular lesions with scales over his scalp, face and trunk, along with polydipsia, polyuria and pain in the abdomen. Histopathology reports showed diffuse infiltration of large cells with eccentric grooved coffee bean nuclei with epidermotropism and admixed with numerous eosinophils. The patient was started on desmopressin, prednisolone and chemotherapy with vinblastine. Our goal is to expand awareness regarding the entity through this report.

Pediatric pulmonary Langerhans cell histiocytosis complicated by recurrent hemopneumothoraces

Langerhans cell histiocytosis is a rare disease of clonal proliferation and deposition of immature dendritic cells in various tissues, including the lungs, causing inflammation and organ destruction. We report a case of a 4-year-old girl with refractory multisystem Langerhans cell histiocytosis complicated by recurrent bilateral hemopneumothoraces in a pediatric tertiary hospital in Cape Town, South Africa. Video-assisted thoracoscopy revealed chronic inflammation of her pleura, with pleural fibrosis seen on histology. Despite pleurodesis, she continued to have recurrent hemopneumothoraces until she was started on a hydroxyurea-containing regimen with a good response.

Chronic health conditions after childhood Langerhans cell histiocytosis: Results from the Swiss Childhood Cancer Survivor Study.

Langerhans cell histiocytosis (LCH) is a rare disease characterized by dysregulated proliferation of myeloid marrow progenitors and subsequent organ infiltration. While LCH is associated with a favorable prognosis, some survivors may develop chronic health conditions (CHC) because of the disease. In this study, we aimed to assess the spectrum and prevalence of CHC among LCH survivors compared with siblings and identify factors associated with the development of CHC. The Swiss Childhood Cancer Survivor Study sent questionnaires to all ≥ 5-year LCH survivors registered in the Swiss Childhood Cancer Registry and diagnosed between 1976 and 2015. Siblings also received similar questionnaires. We compared CHC prevalence between LCH survivors and siblings and used logistic regression to identify determinants of CHC. A total of 123 LCH survivors participated in the study, with a response rate of 69%. Median time since diagnosis was 13years (interquartile range 9-20). Among LCH survivors, 59% had at least one CHC. Cardiovascular (13% vs. 6%), endocrine (15% vs. 2%), musculoskeletal (22% vs. 13%), and digestive (15% vs. 8%) CHC were more common among LCH survivors compared to siblings (all p < 0.05). Factors most strongly associated with the occurrence of CHC were multisystem LCH, multifocal bone involvement, and involvement of the pituitary gland. More than half of long-term LCH survivors suffered from one or more CHC and were affected considerably more than siblings. LCH survivors in follow-up care should be screened especially for cardiovascular, endocrine, musculoskeletal, and digestive conditions.

Adult‐onset BRAF V600E‐related multisystem Langerhans cell histiocytosis treated with vemurafenib

AbstractWe report a case of a 65‐year‐old female with 1‐year history of dental pain and oral ulcers. A diagnosis of Langerhans cell histiocytosis (LCH) was made by oral biopsy and CD207 (Langerin) stain, and BRAF V600E mutation was identified. PET/CT revealed an enhancing lesion in the hard palate with extension into the maxillary sinus. Chemotherapy with cytarabine failed, and LCH progressed to affect additional organ systems. Treatment with vemurafenib was started, resulting in a dramatic improvement of painful mucocutaneous ulcers since the first month of treatment. Vemurafenib is effective in children with refractory BRAF V600E‐mutated LCH, and recent data support the use of vemurafenib in adults with refractory multisystem LCH harbouring the same mutation.

Peroxisome proliferator-activated receptorα/γ agonist pioglitazone for rescuing relapsed or refractory neoplasias by unlocking phenotypic plasticity.

A series of seven clinical trials on relapsed or refractory (r/r) metastatic neoplasias followed the question: Are networks of ligand-receptor cross-talks that support tumor-specific cancer hallmarks, druggable with tumor tissue editing approaches therapeutically exploiting tumor plasticity? Differential recombinations of pioglitazone, a dual peroxisome-proliferator activated receptorα/γ (PPARα/γ) agonist, with transcriptional modulators, i.e., all-trans retinoic acid, interferon-α, or dexamethasone plus metronomic low-dose chemotherapy (MCT) or epigenetic modeling with azacitidine plus/minus cyclooxygenase-2 inhibition initiated tumor-specific reprogramming of cancer hallmarks, as exemplified by inflammation control in r/r melanoma, renal clear cell carcinoma (RCCC), Hodgkin's lymphoma (HL) and multisystem Langerhans cell histiocytosis (mLCH) or differentiation induction in non-promyelocytic acute myeloid leukemia (non-PML AML). Pioglitazone, integrated in differentially designed editing schedules, facilitated induction of tumor cell death as indicated by complete remission (CR) in r/r non-PML AML, continuous CR in r/r RCCC, mLCH, and in HL by addition of everolimus, or long-term disease control in melanoma by efficaciously controlling metastasis, post-therapy cancer repopulation and acquired cell-resistance and genetic/molecular-genetic tumor cell heterogeneity (M-CRAC). PPARα/γ agonists provided tumor-type agnostic biomodulatory efficacy across different histologic neoplasias. Tissue editing techniques disclose that wide-ranging functions of PPARα/γ agonists may be on-topic focused for differentially unlocking tumor phenotypes. Low-dose MCT facilitates targeted reprogramming of cancer hallmarks with transcriptional modulators, induction of tumor cell death, M-CRAC control and editing of non-oncogene addiction. Thus, pioglitazone, integrated in tumor tissue editing protocols, is an important biomodulatory drug for addressing urgent therapeutic problems, such as M-CRAC in relapsed or refractory tumor disease.

A Case of Spontaneous Regression of Adult Multi-system Langerhans Cell Histiocytosis Presenting as Liver Tumor Rupture

A Case of Spontaneous Regression of Adult Multi-system Langerhans Cell Histiocytosis Presenting as Liver Tumor Rupture

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.

Efficacy and safety of intermediate-dose cytarabine in the treatment of children with refractory high risk Langerhans cell histiocytosis

Objective: To analyze the efficacy, safety, and long-term prognosis of intermediate-dose cytarabine (Ara-c) regimen in the treatment of children with refractory risk organ involvement Langerhans cell histiocytosis (LCH). Methods: Clinical data of 17 children with multisystem and risk organ involvement LCH who failed the first-line therapy and were treated with intermediate-dose Ara-c (250 mg/m2, twice daily) regimen in the Hematology Center, Beijing Children's Hospital from January 2013 to December 2016 were analyzed retrospectively. In addition to the basic treatment of vindesine and dexamethasone, the patients received two regimens: regimen A: the intermediate-dose Ara-c combined with cladribine and regimen B: the intermediate-dose Ara-c alone. The efficacy, safety and prognosis of the two regimens were analyzed. Results: Among all 17 patients, there were 11 males and 6 females, with the diagnosis age of 2.1 (1.6, 2.7) years. Ten children received regimen A, all of them achieved active disease-better (AD-B) after 8 courses of induction therapy. The disease activity scores (DAS) decreased from 5.5 (3.0, 9.0) to 1.0 (0, 2.3). Seven children received regimen B, and 6 of them achieved AD-B after 8 courses of induction therapy. The DAS decreased from 4.0 (2.0, 4.0) to 1.0 (0, 2.0). The follow-up time was 6.2 (4.9,7.2) and 5.2 (3.7,5.8) years in group A and B. The 5-year overall survival rate was 100.0% in both groups, and the 5-year event free survival rate was (88.9±10.5)% and (85.7±13.2)% in group A and B. Grade 3 or 4 myelosuppression was observed in 8 patients in group A and 2 patients in group B. Conclusions: The intermediate-dose Ara-c regimen (with or without cladribine) is effective and safe for patients with refractory high-risk LCH, with a good long-term prognosis.

A Rare Case of CD1a +/CD207 + and S100 - Langerhans Cell Histiocytosis with Multi-System Risk Organ Involvement in Adult

Introduction: Langerhans Cell Histiocytosis (LCH) is a rare neoplastic disorder of myeloid dendritic cell precursors, leading to a spectrum of organ involvement and dysfunction. The nonspecific presentations result in missed or delayed diagnoses in adults, and data to guide the clinical care of adults with LCH is limited to case studies and series. Case Description: A 40-year-old Hispanic woman presented to the Emergency Department with ongoing symptoms of shortness of breath, muscle cramps, and intermittent chest pain for two weeks. She was found to have microcytic-hypochromic anemia requiring packed Red Blood Cells (pRBC) transfusion. A CT pulmonary angiogram showed incidental findings of splenomegaly and right axillary lymphadenopathy. A month before this presentation, she was evaluated for symptoms of polyuria, polydipsia, nocturia, and amenorrhea, ongoing for eight months. Arginine Vasopressin Deficiency (AVP-D) was diagnosed, and desmopressin was initiated. MRI Brain had revealed enhancement of the infundibular stalk. On follow-up in the clinic, an ultrasound of the right axilla showed a 2.4 cm lymph node (LN) with thickened cortex. Over the following month, she continued to require multiple pRBC transfusions. Further workup with Fluorodeoxyglucose (FDG)-Positron Emission Tomography (PET) revealed hypermetabolic splenomegaly with multifocal uptake, including the right axilla suspicious for metastatic disease. ( Figure 1-A) A biopsy of the right axillary LN ( Figure 2 - A, B) showed clusters of Langerhans cells and immunohistochemistry positive for CD1a, CD3, CD20, CD68, keratin, and CD 207 (Langerin) staining and variable positivity for S100. Next-Generation Sequencing showed BRAF V600E missense mutation and NOTCH3, DICER1, CREBBP, JAK1, and CTNNA1 as Variants of Unknown Significance (VUS). Bone marrow (BM) aspirate and flow cytometry were unremarkable. A diagnosis of Multi-System LCH with Risk Organ Involvement (MS-RO +) was made. Cytarabine therapy was started at 150 mg/m 2(days 1-5, 28-day cycle). She was hospitalized twice due to sepsis, leukocytosis, severe anemia: Hemoglobin (Hb) 3.1, and grade 4 thrombocytopenia. Cycle 2 was delayed, and the dose was reduced to 50%. Post-infusions, Hb decline necessitated multiple pRBC transfusions. Repeat FDG-PET after cycles 2 and 5 ( Figure 1-B, C) showed continued metabolic and anatomic response to therapy. A repeat brain MRI showed no change in pituitary findings. The patient continues to improve clinically with plans to complete a total of one year of chemotherapy. Discussion: LCH is defined by the presence of CD1a +/CD207 + histiocytes. Although usually positive for S-100, rare S-100 negative variants have been reported in skin-limited LCH and LC-Sarcoma. An aberrant maturation process was proposed as a possible explanation, but the exact pathology remains unknown. In children &amp;lt;15 years, the incidence is 2.6-8.9 cases/million/year; in adults, the incidence is less defined at 0.07 cases/million/year and is higher in Hispanics. Adult LCH typically presents after the fourth decade; two-thirds have multi-system involvement. Hematopoietic dysfunction, cytopenias, and liver involvement carry a poor prognosis. AVP-D is the most frequently associated endocrine abnormality. Whole-exome sequencing has shown very low somatic mutation frequency in LCH compared to other neoplastic disorders. BRAF, a central kinase in the RAS-RAF-MEK pathway, has a missense V600E mutation in roughly 50% of LCH, rendering it constitutionally active. Other mutations include BRAF, MAP2K1, ARAF, ERBB3, NRAS, and KRAS, but the VUS mentioned above have been reported infrequently. The LCH-III trial confirmed Vinblastine/Prednisone as the standard regimen for MS-LCH patients &amp;lt;18 years, with or without RO involvement. While it is effective in adults, its limited tolerance favors the use of cytarabine or cladribine. NCT02670707 is an ongoing trial comparing cytarabine monotherapy versus Vinblastine/Prednisone for frontline treatment. BRAF inhibitors are also being increasingly investigated. Prospective trials to optimize the duration of therapy (LCH-IV) and potential combination therapies are currently underway.

Pediatric pulmonary multisystem langerhans cell histiocytosis: does lung lesion severity affect the outcome?

BackgroundThe pediatric pulmonary multisystem Langerhans cell histiocytosis (PPM LCH) is associated with either low risk or high risk organ(s). The nodulo-cystic lung lesions although pathognomonic, yet are very variable in severity and remain a source of controversy in certifying pulmonary LCH diagnosis. The study aimed to examine the prognostic value of clinical respiratory manifestations and radiological lung lesions severity. This is through associating a CT chest triad of bilateral, extensive and diffuse lesions. It is a retrospective study of 350 LCH patients who received systemic treatment at Children’s Cancer Hospital Egypt during the period from 2007 to 2020.ResultsSixty-seven patients (67/350–19.1%) had PPM LCH at presentation. Severe lung lesions were present in 24 of them. The median follow-up period was 61 months (IQR: 3.4–8.3). The 5-year overall survival (OS) and event free survival (EFS) was 89% and 56.6% respectively. The EFS, for severe radiological lesions triad was 38% ± 20.7 versus 66% ± 16.2 for non-severe lesions triad p 0.002, while for presence of chest X-ray changes 27% ± 22.344 versus absence of chest X ray changes 66% ± 14.7 p 0.001, for clinical respiratory manifestations 13% ± 13.9 versus none 62% ± 22.9 p < 0.001, for RO− with severe lung lesions 47% ± 30.4 versus RO− without severe lung lesions 69% ± 5.9 p 0.04. There was a tendency for the independent prognostic impact of severe lung involvement; aHR = 1.7 (95% CI 0.92–3.13, p = 0.09).ConclusionAlthough the lung is a low -risk organ per se in LCH, our study demonstrates a non negligeable prognostic impact of severe lung involvement in the risk stratification of pediatric LCH. This warrants further study and external validation.

Cutaneous lesions, polyuria, polydipsia, and adenopathies in a pediatric patient

This abstract presents a case of multisystemic Langerhans cell histiocytosis (LCH) in a 3-year-old boy with diverse clinical manifestations, including language delay, recurrent acute otitis media, pruritic scalp plaques, and erythematous trunk papules. Laboratory and radiological findings supported the diagnosis, which was confirmed by histopathological analysis and immunohistochemical markers. The case underscores the importance of recognizing skin involvement as an initial presentation and highlights evolving therapeutic strategies, including targeted inhibitors, for improved LCH management.

Clinical Characteristics, Genomic Profiling and Outcomes of Langerhans Cell Histiocytosis in Adults with Single System Multifocal Disease

Background Langerhans cell histiocytosis (LCH) is a rare, heterogeneous histiocytic neoplasm. There are few studies focusing on LCH in adults with single system multifocal disease (SS-m). Methods This retrospective study enrolled 43 LCH in adults with SS-m from 422 adult LCH at Peking Union Medical College Hospital between January 2001 and May 2023. We analyzed the clinical characteristics, genomic profiling, treatment approaches, and outcomes of LCH in adults with SS-m. Results Of all patients, the median age at diagnosis was 34 years (range, 21-65 years) with a male-to-female ratio of 1.7:1. The median duration from symptom onset to diagnosis was three months (range, 1-130 months). All patients had bone involvement. Bone pain (90.7%) was the most common symptom, followed by tumor formation in a localized area of bone (11.6%), toothache (4.6%), and hearing impairment (2.3%). The median number of bone lesions was three (range, 2-11). The most common bone invasion sites were the ribs (51.2%), followed by the pelvis (46.5%), spine (39.5%), skull (30.2%), and maxillofacial bones (30.2%). Twenty-three patients (53.5%) had central nerve system (CNS)-risk lesions involvement. Of the 28 patients with next-generation sequencing, the median number of gene mutations was two (range, 1-9), and the overall percentage of MAPK pathway mutations was 64.3%. BRAF V600E, MAP2K1, and BRAF indelmutations were detected in 35.7%, 7.2%, and 3.6% of patients, respectively (Figure1 A). The initial treatments divided into local therapy (n = 6) and systemic therapy (n = 30). Systemic therapy included 18 received cytarabine monotherapy, six received methotrexate combined with cytarabine, four received vindesine and prednisone-based regimens, and two who had CNS-risk lesions involvement received BRAF inhibitors (Figure1 B). After a median follow-up of 43 months (range, 1-218 months), one patient died due to disease progression, and 13 patients had reactivation, including 8 with bone lesions, and 5 progressed to multisystem LCH. The 3-year overall survival and progression-free survival (PFS) rates were 97.4%, and 75.4%, respectively. Univariate analysis showed that systemic therapy (36.3 months vs. 28.0 months, P= 0.013) and non-CNS-risk lesions involvement (36.0 months vs. 23.0 months, P = 0.016) were associated with a better PFS (Figure1 C, D). Conclusions The overall percentage of MAPK pathway mutations in adult LCH with SS-m was low. Systemic therapy should be considerd as first-line treatment for LCH in adults with SS-m, and CNS-risk lesions involvement predicted a poor prognosis. Figure Captions Figure1. A. Next-generation sequencing of lesion tissues of LCH in adults with single-system multifocal disease (SS-m); B. Treatment and outcomes of adult patients with SS-m; C. Progression-free survival (PFS) according to first-line treatment; D. PFS according to CNS-risk lesions involvement at baseline

Multisystem Langerhans cell histiocytosis presenting in adulthood. Don't forget the mouth!

Multisystem Langerhans cell histiocytosis presenting in adulthood. Don't forget the mouth!

A rare case of high risk multisystem Langerhans Cell Histiocytosis in infant

Objective: Langerhans cell histiocytosis (LCH) stands as the most common histiocytic disorder. It is categorized into single-system single site, single-system multi-site, and multisystem types, with or without involvement of risk organs. Clinical presentation exhibits considerable variability, contingent upon the affected organ systems. Given its rarity, diverse locations, and varying severity, there are currently no established treatment guidelines for LCH. Case Presentation: We documented the case of a 5-month-old male diagnosed with Langerhans cell histiocytosis (LCH), presenting with high-risk multisystem organ involvement and concurrent unifocal bone involvement. Bone marrow aspiration revealed infiltration by multinucleated giant cells within the marrow. Skin biopsy demonstrated Langerhans cell proliferation with epidermotrophism and the characteristic reniform nucleus resembling a coffee bean. The patient was treated following the histiocytosis protocol, which included daily oral prednisone and 6-mercaptopurine, in addition to weekly intravenous vinblastine and methotrexate administered every two weeks. Unfortunately, the patient displayed limited response during the initial phase of treatment and, tragically, passed away during the eighth week of therapy. Conclusion: Langerhans cell histiocytosis (LCH) is a rare disease characterized by variable disease presentations and is associated with significant morbidity and mortality. Timely recognition of clinical manifestations and risk factors, coupled with appropriate treatment, is crucial to reduce mortality and long-term complications associated with the condition.