Diverse Cutaneous Presentations of Langerhans Cell Histiocytosis in Children: A Retrospective Cohort Study

Large Congenital Cutaneous Mastocytoma Presenting With Recurrent Persistent Blistering: A Case Report

Congenital cutaneous mastocytoma is an uncommon disorder characterized by abnormal proliferation of mast cells. It typically presents as a single, small, yellowish-brown plaque, and its diagnosis is generally facilitated by distinctive clinical features, including a positive Darrier's sign. This report presents a case of an unusually large, solitary congenital mastocytoma encompassing nearly the entire circumference of the calf, observed in a newborn boy of Bangladeshi origin. Measuring 13x6 cm, the lesion formed large bullae and subsequent erosions. The perplexing clinical appearance prompted a skin biopsy, revealing monomorphic CD117 (c-KIT) positive infiltration without significant cell pleomorphism, confirming the diagnosis of cutaneous mastocytoma. The patient underwent management with potent and very potent topical steroids, oral antihistamines, and non-adhesive dressings, remaining under long-term follow-up with secondary care dermatology. In reporting this case, our objective is to augment the existing scientific literature by providing additional evidence that cutaneous mastocytomas can display a spectrum of clinical presentations, as illustrated in this case.

Adult multisystem Langerhans cell histiocytosis with cutaneous involvement manifesting as extensive flexural erosions

Langerhans cell histiocytosis is a great imitator of other diseases with an often-delayed diagnosis leading to a concerning delay in commencing treatment. We present the case of a male who was previously diagnosed with Hailey-Hailey disease, in whom several treatment options had failed, was referred to the dermatology team for evaluation of a 3-month atypical, extensive, painful and pruritic cutaneous flexural eruption. On systems review, he reported a 2-year history of polyuria and polydipsia. Repeat skin biopsy revealed a prominent histiocytic infiltrate on histopathology with corresponding positive expression of Langerin (CD207), S100, CyclinD1 and p-ERK on immunohistochemistry staining. An MRI of the brain demonstrated posterior pituitary enhancement. The clinical presentation, biopsy and investigations confirmed a diagnosis of a multisystem Langerhans cell histiocytosis, which resulted in longstanding patient morbidity. With considerable multidisciplinary teamwork, a gradual and sustained resolution of his lesions, pain, polyuria and polydipsia was achieved.

Langerhans Cell Histiocytosis in Children: Literature Review

Relevant information on Langerhans cell histiocytosis development and course in children is presented. The current concepts of disease pathogenesis, principles of its severity evaluation, patients stratification into risk groups, as well as of clinical course features are described. Modern approaches to the disease treatment via targeted therapy are summarized and analyzed. 

BRAF Mutation Analysis in Two Cases of Congenital Self-Healing Langerhans Cell Histiocytosis

Congenital self-healing Langerhans cell histiocytosis (CSHLCH) is a rare type of Langerhans cell histiocytosis (LCH). Here, we report two cases of CSHLCH. The cases presented solitary and multiple skin lesions of various sizes. The diagnosis was confirmed by skin biopsies. The lesions disappeared after one to two months without therapeutic intervention. No BRAF mutations in the skin lesions were detected, and soluble interleukin-2 receptor (sIL-2R) was normal in both cases. Recent studies suggested that the state of differentiation of the precursor cell in which BRAF mutations occur is associated with the clinical types and prognosis of the disease. Further investigation should be needed to elucidate the association between the progression and regression of CSHLCH and BRAF mutation.

Dermatologic masks of Langerhans cell histiocytosis. Case report

Langerhans cell histiocytosis (LCH) is a rare pathology in pediatric age with heterogeneous clinical presentation in skeletal system, skin, central nervous system, liver, spleen, lungs, lymph nodes and bone marrow. Therefore, a number of diagnostic mistakes increase and inadequate therapy administrates. For a diagnostic period, a try at treatment, LCH disseminates with organs and systems involvement and at the moment of morpho-immunologic diagnosis verification, a disease characterizes as multiorgan multiple site affection, which decreased survival rate. In the current issue a clinical case of LCH with mistaken prolonged (2 year) atopic dermatitis anamneses is presented. The absence of pronounced effect of topical therapy along with nontypical for atopic dermatitis became not an indication for skin biopsy. After appearance of systemic symptoms with anemia, leuko- and thrombocytopenia became an evidence for pediatric oncologist-hematologist consultation.

Integrated imaging of systemic Langerhans cell histiocytosis in an infant

Langerhans cell histiocytosis (LCH) is a myeloid neoplasm characterized by a clonal proliferation of CD1a+/CD207+ dendritic cells. Although individuals of any age can be affected, the disease is most common in infants younger than 5 years of age, especially males. A wide range of manifestations, from asymptomatic to aggressive, have been described, along with multiorgan involvement. Even though the majority of bone lesions are observed, skin, lymph nodes, brain and lungs can also be involved. The involvement of hematopoietic system, including bone marrow, liver and spleen, is less frequent yet associated with worse prognosis, due to a worse treatment response. Diagnosis of LCH is based on the integration of clinical, laboratory, and radiological data; however, only histopathological examination might confirm it. As far as the spleen involvement is concerned, according to literature, it has been reported in about 15% patients with multisystem involvement, nonetheless only a few cases show parenchymal lesions. The present study reports the case of an infant with LCH with multisystem involvement, including bone, skin, liver, and spleen, with evidence of parenchymal lesions.

Langerhans cell histiocytosis. Advances in pathogenesis and clinical practice

Langerhans cell histiocytosis (LCH) is a type of myeloid neoplasia that can affect different organs or tissues and exhibits substantial variability in its clinical presentation and biological behaviour, so it may mimic different diseases. Performance of different clinical assessments and laboratory and imaging tests is recommended to determine the extent of involvement, which may be of a single location or multisystemic, and the presence or absence of dysfunction in risk organs, such as the haematopoietic system, liver and spleen. The diagnosis must be confirmed by histological examination of a biopsy sample. Molecular tests have identified mutations in the mitogen-activated protein kinase (MAPK) pathway, which has expanded treatment options. The diagnosis is complex and there is controversy regarding the management of certain cases. Treatment recommendations depend on the location of the lesions and the extent of involvement. International collaborative studies have demonstrated the effectiveness of prolonged combination therapies such as vinblastine and prednisone in severe or multisystemic forms, and anti-inflammatory drugs such as indomethacin and other cytostatic combinations have proven beneficial. Langerhans cell histiocytosis is a good example of the importance of precision medicine and the benefit of identifying molecular targets, common to different neoplasms, to develop new therapies. MAPK pathway inhibitors offer an alternative treatment option in refractory cases and neurodegenerative forms of LCH. Molecular testing can contribute to the prognosis, treatment and follow-up of LCH, especially in severe forms of disease.

Dermoscopic feature analysis of different skin lesions of Langerhans cell histiocytosis

Dermoscopy was used to investigate skin lesions in 15 children with Langerhans cell histiocytosis (LCH). Purplish red globules or patches could be seen in different rashes under dermoscopy, and histopathology showed extravasation of red blood cells. Dermoscopy findings were highly consistent with histopathology results. Purplish red globules or patches could be used as important features in dermoscopy test and differential diagnosis.of LCH.

Head and Neck Langerhans Cell Histiocytosis in Children

PURPOSE

Controversy exists among head and neck surgical specialties regarding management of Langerhan's Cell Histiocytosis (LCH). The purpose of this study was to evaluate diagnosis, management, and treatment outcomes in children with LCH of the head and neck.

METHODS

This is a retrospective cohort study of children with LCH of the head and neck who presented to Children's Healthcare of Atlanta hospital from 2009 to 2021. The independent variables were demographic information, lesion locations, clinical presentation, radiographic findings, diagnostic workup, treatment, and length of follow-up. The patients were grouped based on these variables. The outcome variable was disease reactivation. Descriptive statistics were calculated.

RESULTS

There were 3 presentations of LCH of the head and neck. Group 1 presented as a lesion in 1 system without CNS risk (SS-). There were 24 patients with an average age of 10 years. Lesions were located in calvaria and/or mandible. Majority of the patients were treated with only debridement. Two of the patients experienced reactivation. Group 2 presented as a lesion in 1 system with CNS risk (SS+). There were 30 patients with an average age of 6 years. Common locations were temporal bone and/or orbit. These patients present with recurrent ear infections and ptosis. Majority of the patients were treated with chemotherapy (n = 28). One patient had disease reactivation. Group 3 presented with multisystem involvement. There were 13 patients with an average age of 2 years. LCH was found in skin and the lymphatic system. Imaging demonstrated extracranial organ involvement. All of them were treated with chemotherapy. There was 40% reactivation of LCH.

CONCLUSIONS

Treatment of LCH depends on presentation. SS- subgroup can be adequately treated via surgical debridement. SS+ and multisystem groups benefit from an early disease diagnosis and require chemotherapy.

Clinical features and treatment of Langerhans cell histiocytosis

Langerhans cell histiocytosis (LCH) is caused by the expansion of CD1a+/CD207+ cells and is characterised by a wide spectrum of organ involvement and dysfunction, affecting all ages. While almost all organs and systems can be affected, only the involvement and dysfunction of liver, spleen, and haematopoietic system influence survival. The LCH pathogenic cells are defined by universal activation of the mitogen-activated protein kinase (MAPK) signalling pathway. The most common alteration is a somatic BRAFV600E mutation, which is present in approximately two-thirds of the cases, followed by MAP2K1 mutations. Treatment of LCH is risk-adapted; patients with single lesions may respond well to local treatment, whereas patients with multi-system disease require systemic chemotherapy. While survival for patients without organ dysfunction is excellent, mortality rates for patients with organ dysfunction may reach 20%. Despite progress made in the treatment of LCH, disease reactivation rates remain above 30%, and standard second-line treatment has yet to be established. Long-term effects, including neuroendocrine dysfunction and neurodegeneration, represent a major challenge for survivors. Treatment with BRAF or MEK inhibitors results in immediate responses, but reactivations are very common after discontinuation. Their role as single agents and in combination with chemotherapy is being explored.

What to Look Out for in a Newborn with Multiple Papulonodular Skin Lesions at Birth

Multiple papulonodular skin lesions at birth can indicate the presence of various benign and malignant disorders. Although the lesions’ clinical aspect (color and consistency, in particular) may steer the clinician towards one disorder or another (infantile myofibromatosis, xanthogranuloma, or metastatic neuroblastoma), the diagnosis can only be confirmed by the histopathologic assessment of a biopsy. In neonates, a rapid but accurate diagnosis is critical because skin lesions may be the first manifestation of a malignant disorder like leukemia cutis or metastatic neuroblastoma. Here, we review the various disorders that may manifest themselves as multiple skin lesions at birth.

Mitogen-activating protein kinase pathway alterations in Langerhans cell histiocytosis

PURPOSE OF REVIEW

Langerhans cell histiocytosis (LCH) is a rare disorder characterized by the infiltration of involved tissues by specialized dendritic cells. The demonstration of the constant activation of the mitogen-activated protein kinase (MAPK) pathway in LCH lesions has been a breakthrough in the understanding of the pathogenesis of this rare disease. We will summarize the current knowledge on MAPK alterations in LCH and the new therapeutic options indicated by these findings.

RECENT FINDINGS

Since the description of the B-Raf proto-oncogene, serine/threonine kinase (BRAF)V600E mutation in LCH lesions, several other molecular alterations affecting the MAPK pathway have been identified in most cases. Based on these driver alterations, LCH cells were shown to be derived from hematopoietic precursors, which yielded the current concept of LCH as a myeloid inflammatory neoplasia. MAPK pathway inhibitors have emerged as an innovative therapy in severe forms of LCH, resulting in virtually no acquired resistance. However, although they are highly effective, their effect is only temporary, as the disease relapses upon discontinuation of the treatment.

SUMMARY

LCH is an inflammatory myeloid neoplastic disorder, driven by mutations activating the MAPK pathway. MAPK-targeted treatments represent an important stepforward in the management of patients with severe progressive LCH.

Langerhans cell histiocytosis: A rare aetiology for fetal pleural effusion

OBJECTIVE

We present fetal pleural effusions associated with Langerhans cell histiocytosis (LCH).

CASE REPORT

We report a case of fetal pleural effusion in late pregnancy. Due to developing rapidly over short period of time, the baby was delivered by caesarean section at 34 weeks gestation. Generalised oedema, sparse haemorrhagic papules, pulmonary involvement, mediastinal mass and liver dysfunction were identified postnatally. Structural malformations, maternal-fetal blood type incompatibility, chromosomal abnormalities and viral infection were excluded. Mediastinal mass biopsy and immunohistochemical examinations confirmed the diagnosis of Langerhans cell histiocytosis (LCH). The baby is currently in a stable condition and undergoing regular chemotherapy.

CONCLUSIONS

Congenital LCH is a rare aetiology of fetal pleural effusions.

How to Deal with Skin Biopsy in an Infant with Blisters?

The onset of blisters in a neonate or an infant is often a source of great concern for both parents and physicians. A blistering rash can reveal a wide range of diseases with various backgrounds (infectious, genetic, autoimmune, drug-related, traumatic, etc.), so the challenge for the dermatologist and the pediatrician is to quickly determine the etiology, between benign causes and life-threatening disorders, for a better management of the patient. Clinical presentation can provide orientation for the diagnosis, but skin biopsy is often necessary in determining the cause of blister formations. In this article, we will provide information on the skin biopsy technique and discuss the clinical orientation in the case of a neonate or infant with a blistering eruption, with a focus on the histology for each etiology.

Langerhans’ cell histiocytosis diagnosed due to dermatological perianal lesion

Langerhans’ cell histiocytosis is a rare disease characterized by proliferation of Langerhans cells in the body. It affects mainly males, predominantly in childhood. Ulcerated plaques are one of the cutaneous forms of presentation. Diagnostic confirmation is done through immunohistochemistry. As therapeutic options, topical corticosteroids and chemotherapy are good choices. The case is reported of a male patient, aged 14, with perianal ulceration. He consulted a coloproctologist, who performed a biopsy of the region and started local triamcinolone applications. Immunohistochemistry diagnosed Langerhans’ cells histiocytosis. Further investigation revealed diabetes insipidus, osteolytic lesions in the skull and lower limbs, enlarged liver, and encephalic alterations. Chemotherapy was started with Vinblastine, with significant improvement of the lesions.

Solitary congenital Langerhans cell histiocytoma: A pattern of benign, spontaneous regression in patients with single lesion disease

Langerhans cell histiocytosis (LCH) is the neoplastic proliferation of dendritic langerin-positive histiocytes manifesting as either single system unifocal, single system multifocal, or multisystem disease. The designation Hashimoto-Pritzker, or self-healing LCH, has fallen out of favor since it is impossible to predict at time of diagnosis whether the disease is truly self-remitting or capable of spreading to other organ systems. We review the English literature on solitary congenital Langerhans cell histiocytoma, draw novel conclusions from the data provided by 81 cases in the literature, and illustrate a typical presentation of the diagnosis with a previously unreported patient. Each of the patients diagnosed with solitary congenital histiocytoma experienced spontaneous resolution and had no signs of systemic disease at latest follow-up. Furthermore, we offer an analysis of the histopathological findings available from the 81 cases and our patient. Based on our study observations, we propose solitary congenital Langerhans cell histiocytoma may portend a good prognosis and represent a distinct entity. However, until further confirmation with prospective studies, we recommend clinicians continue conducting appropriate workup to rule out systemic involvement.

Langerhans cell histiocytosis in children: A retrospective case series of 126 cases

BACKGROUND/OBJECTIVES

Langerhans cell histiocytosis (LCH), a rare neoplasm of hematopoietic myeloid precursor cells, is clinically characterized by spontaneously resolving lesions to a progressive life-threatening multisystem disorder. Diagnosing LCH in children is challenging as it mimics other skin disorders. This study describes the varied clinical presentation and disease course in children less than 18 years diagnosed with LCH.

METHODS

We performed a retrospective observational study of all cases diagnosed with LCH presenting to a children's hospital in the last 26 years. Data on history, cutaneous and systemic examination, and laboratory evaluation performed, were recorded.

RESULTS

A total of 126 children diagnosed with LCH were included in the study. There were 68% cases limited only to skin, and 32% children with multisystem involvement at the initial presentation. Scaly papules were the most common morphologic finding in skin. The skeletal system was the second most common organ system to be affected. Failure to thrive was a common symptom. Progression of skin to systemic involvement was seen in 27.9%. In 76.7%, skin lesions cleared over a period of 2 to 4 years. Complete remission was seen in 56.9% of children over a period of 3 to 7 years, while 8.1% children died of complicationsand 31.8% were lost to follow-up.

CONCLUSIONS

Long-term follow-up in this study has shown cutaneous LCH without systemic involvement has a good prognosis. Skin involvement,along with failure to thrive, was the most common clinical presentation in our study. The skeletal system was the second most common organ system involved.

Clinical characteristics and outcome of pediatric patients diagnosed with Langerhans cell histiocytosis in pediatric hematology and oncology centers in Poland

Background

Langerhans cell histiocytosis (LCH) affects 1–2 in 1,000,000 people. The disease is not associated with increased risk of treatment failure (especially among older children), but appropriate procedures implemented in advance can eliminate complications which might appear and significantly worsen the patients’ quality of life. Thus, we sought to evaluate the clinical features, management, and outcome of children with LCH treated in Polish pediatric hematology-oncology centers.

Materials and methods

One hundred eighty two patients with LCH were treated according to the Histiocytic Society Guidelines between 2010 and 2017. The participating centers were requested to provide the following data: demographic, clinical, as well as local or systemic treatment data and patients’ outcome. Overall survival (OS) and event free survival (EFS) were estimated by Kaplan-Meier methods and compared using the log-rank test.

Results

Sixty nine percent of children were classified as single system (SS). The patients with SS disease were significantly older as compared to the children with multisystem disease (MS), 6 vs. 2.3 years respectively (p 0.003). Bones were involved in 76% of patients. Systemic treatment was applied to 47% of children with SS disease and 98% with MS disease. Fourteen patients relapsed while two children died. OS and EFS in entire group were 0.99 and 0.91 respectively (with median follow-up 4.3 years).

Conclusion

The treatment of LCH in Polish centers was effective, however, new approaches, including mutation analyses and good inter-center cooperation, are needed to identify patients who might require modification or intensification of treatment.

Congenital Unilesional Cutaneous Langerhans Cell Histiocytosis: A Case Report

ABSTRACT

Langerhans cell histiocytosis (LCH) is a clonal proliferation of bone-marrow-derived cells, which normally reside as epidermal and mucosal dendritic cells involved in antigen presentation. It is a rare disease more common in children than adults, that is believed to be neoplastic in most cases. The diagnosis is based on clinical and radiological findings in combination with histopathologic, immunophenotypic, or ultrastructural analyses. LCH have a broad spectrum of clinical manifestations, ranging from benign cutaneous lesions to malignant multisystem disease. Based on the extent of involvement at diagnosis, LCH can be divided in single-system LCH when only one organ or system is involved, usually with multiple lesions, and multisystem LCH, when 2 or more organs or systems are involved at diagnosis. One variant of LCH is characterized by congenital isolated cutaneous involvement. It typically manifests at birth or in the postnatal period with a widespread eruption of red-to-brown papulo-nodules or, more uncommonly, a solitary lesion. The overall prognosis for single lesion skin limited LCH is excellent and most lesions spontaneously resolve within 4-18 weeks. Systemic involvement is rare. Skin findings cannot predict systemic disease and obtaining an oncology consultation is recommended for further evaluation. Herein, we present an additional case in a full-term, well-appearing, female infant with an isolated, asymptomatic, ulcerated, papule of the left arm, that was noted at birth.

A neonate with Langerhans cell histiocytosis presenting as blueberry muffin rash: Case report and review of the literature

In our case report, we discuss a 1-day-old boy presenting with blueberry muffin syndrome diagnosed with Langerhans cell histiocytosis. The diagnosis complicated by an initial difficult-to-interpret biopsy showing only a hint of perifollicular CD1a-positive cells; however, given our team’s strong clinical suspicion of Langerhans cell histiocytosis, a second biopsy of a more mature lesion was done and showed typical histopathology. This case introduces the possibility of perifollicular Langerhans cells early in this condition, demonstrates the importance of appropriate biopsy site selection, and highlights the importance of maintaining a high degree of suspicion when there is poor clinicopathologic correlation. Our case report contains a comprehensive table which reviews the systemic and cutaneous clinical features, as well as the laboratory, pathology, and imaging findings for the differential diagnoses of blueberry muffin baby.

Childhood Langerhans cell histiocytosis: a disease with many faces

BACKGROUND

Langerhans cell histiocytosis (LCH) is a group of diseases characterized by the proliferation and accumulation of Langerhans cells. Clinical presentations of LCH vary widely.

DATA SOURCES

A PubMed search was conducted using Clinical Queries with the key term "Langerhans cell histiocytosis". The search strategy included meta-analyses, randomized controlled trials, clinical trials, observational studies, and reviews. This paper is based on, but not limited to, the search results.

RESULTS

Generally, patients with LCH can be divided into two groups based on the extent of involvement at diagnosis, namely, single-system LCH and multisystem LCH. The involvement may be unifocal or multifocal. Patients with isolated bone lesions typically present between 5 and 15 years of age, whereas those with multisystem LCH tend to present before 5 years of age. The clinical spectrum is broad, ranging from an asymptomatic isolated skin or bone lesion to a life-threatening multisystem condition. Clinical manifestations include, among others, "punched out" lytic bone lesion, seborrheic dermatitis-like eruption, erythematous/reddish-brown crusted/scaly papules/maculopapules/plaques/patches, and eczematous lesions, diabetes insipidus, hepatosplenomegaly, cytopenias, lymphadenopathy, and an acute fulminant disseminated multisystem condition presenting with fever, skin rash, anemia, thrombocytopenia, lymphadenopathy, and hepatosplenomegaly. The diagnosis is clinicopathologic, based on typical clinical findings and histologic/immunohistochemical examination of a biopsy of lesional tissue. Positive CD1a, S100, and/or CD207 (Langerin) immunohistochemical staining of lesional cells is required for a definitive diagnosis. Watchful waiting is recommended for patients with skin-only LCH. Patients with symptomatic or refractory skin-only LCH may be treated with topical tacrolimus/corticosteroids, topical nitrogen mustard, oral methotrexate, or oral hydroxyurea. The current recommended first-line therapy for patients with multisystem LCH is 12 months therapy with prednisone and vinblastine. Mercaptopurine is added for patients with risk organ involvements.

CONCLUSIONS

Because of the broad spectrum of clinical manifestations and the extreme diversity of disease, LCH remains a diagnostic dilemma. Morphological identification of LCH cells and positive immunochemical staining with CD1a, S100, and/or CD207 (Langerin) of lesional cells are necessary for a definitive diagnosis.

Localized Acral Sclerosing Langerhans Cell Histiocytosis: A New Form of Presentation of Cutaneous Langerhans Cell Histiocytosis

Langerhans cell histiocytosis (LCH) is a rare proliferative disorder, more frequent in children, characterized by an abnormal accumulation of Langerhans cells admixed with eosinophils, lymphocytes, neutrophils, and macrophages. The clinical presentation is variable and depends on whether a single or multiple organs are affected. Skin lesions are common in LCH (40% of cases) and represent a frequent form of presentation (in up to 80% of cases). Cutaneous manifestations of LCH are highly variable, frequently presenting as crusted papules or scaly seborrheic-like lesions localized in the scalp. We report the first case of a localized acral sclerosing LCH, a new form of LCH. This case highlights the broad and surprising form of presentation of LCH which may be overlooked and can significantly delay its diagnosis. The development of systemic disease may occur months to years after the initial skin presentation. Prompt diagnosis and treatment may prevent progression to systemic disease, as documented in some cases.

Langerhans cell histiocytosis: A great imitator

Langerhans cell histiocytosis (LCH) is an uncommon but serious inflammatory neoplasia that affects many organs, including the skin. Though uncommon, it should remain high on a clinician's differential diagnosis in treatment-resistant cases of conditions, such as seborrheic dermatitis, diaper dermatitis, arthropod bites, and many more. A thorough history nd physical examination for each patient can aid in the diagnosis; however, if clinically suspicious for LCH, a punch biopsy should be performed. Histologic evaluation of LCH is often enough to differentiate it from the many clinical mimickers. Characteristic findings include a histiocytic infiltrate with "coffee bean"-cleaved nuclei, rounded shape, and eosinophilic cytoplasm. Immunohistochemical stains, including CD1a, S100, and CD207 (langerin) are often needed for a definitive diagnosis. Electron microscopy also demonstrates the ultrastructural presence of Birbeck granules, but this is no longer needed due to immunohistochemical staining. Treatment is often necessary for LCH, if systemic involvement exists.

Congenital Self-Healing Langerhans Cell Histiocytosis: A Rare Presentation of Blueberry Muffin Baby "Spectrum"

A case of congenital self-healing Langerhans cell histiocytosis (CSHLCH), also known as Hashimoto-Pritzker disease, is reported. The newborn presented as blueberry muffin baby at birth, showing numerous non-blanching blue-purplish and dark-red papular, nodular lesions without documented infections and systemic involvement. Histopathological and immunohistochemical findings were suggestive for Langerhans cell histiocytosis. During the first 12 weeks of life, the cutaneous lesions progressively and spontaneously regressed with some atrophic scars. One-year follow-up is negative for relapse of cutaneous lesions or systemic involvement, confirming the diagnosis of CSHLCH.

Langerhans Cell Histiocytosis: Single Center Experience of 25 Years

Objectives

To review a single center outcome of patients with Langerhans Cell Histiocytosis diagnosed at a tertiary referral hospital from Turkey.Methods: The files between 1989 and 2015 of 80 patients with LCH were retrospectively analyzed.

Results

During the 25 years, 80 patients were diagnosed with LCH. The median age at diagnosis was 53 months (2-180 months) and the median follow-up time of patients was 10 years and 9 months (24 months-25 years). Bone was the most frequently affected organ (n:60, 75%). Initially, 43 patients (54%) had single system (SS) disease, 20 patients (25%) had multisystem (MS) disease without risk organ involvement (MS-RO^-), and 17 patients (21%) had a multisystem disease with risk-organ involvement (MS-RO⁺). The overall survival (OS) rate was 91%, and event-free survival (EFS) rate was 67% at 10 years. 10-year OS rate was lower for patients with MS-RO⁺ (65%) when compared to those with, MS-RO^-, and SS (100%, 97%, p value=<0.001). The overall survival rate was also lower in patients with lack of response to systemic chemotherapy on 12th week (p=<0.001), younger age (<2 years) at presentation (p=<0.02), skin involvement (<0.001) and lack of bone lesions at presentation (<0.001).

Discussion

In the group with MS-RO⁺, OS is significantly low compared to other groups. Further efforts are warranted to improve survival in MS-RO⁺ patients.

Diverse cutaneous manifestation of Langerhans cell histiocytosis: a 10-year retrospective cohort study

Cutaneous manifestation is a common presentation of LCH and is usually a leading clue for the disease diagnosis. Having cutaneous lesions did not show a significantly early age onset at diagnosis compared to those without skin lesions, P value = 0.71. In the present study, cutaneous findings were found as 77.7%. Seborrheic dermatitis-like lesions were the most common cutaneous type (42.8%), followed by papules/nodules/masses (28.5%), petechiae/hemorrhagic lesions (17.8%), and eczematous lesions (10.7%). Time to diagnosis of LCH presented with seborrheic dermatitis-like lesions was significantly longer than other cutaneous presentations, P value = 0.0011.Conclusion: Patients with LCH who had the manifestations of seborrheic dermatitis-like lesions can have diagnosis delayed due to the difficulty in distinguishing these lesions from normal seborrheic dermatitis lesions. Petechiae/hemorrhagic cutaneous signs in addition to the normal seborrheic dermatitis is the clue for early detection of the disease. To improve early detection of LCH, general pediatricians should be alerted to be aware of these skin symptoms, and if they persist, a dermatologist, pediatric if available, should be immediately consulted. What is Known? • Cutaneous manifestation is a common presentation of LCH and is usually a leading clue for the disease diagnosis. What is New? • Patients with LCH who have the manifestations of seborrheic dermatitis-like lesions can have a delayed diagnosis due to the difficulty in distinguishing normal from seborrheic dermatitis lesions. • Petechiae/hemorrhagic cutaneous signs in addition to the normal seborrheic dermatitis are the clue to the early disease detection.

Infiltrating the Heart and Kidney: A Rare Pediatric Case of Multisystem Langerhans Cell Histiocytosis from Pakistan

Langerhans cell histiocytosis (LCH) is a rare, clonal disease of the monocyte-macrophage system, varying in its clinical presentation from mere self-healing skin and bone lesions to life-threatening multi-system disease. In descending order of frequency, the disease is known to involve the skeleton, skin, lymph nodes and lesser often, the liver, spleen, lungs, hematopoietic and central nervous systems. Here, we present a pediatric case of multi-system LCH in a five-year-old child, unique in its evident cardiac and renal involvement alongside other organ systems and important in how the diagnosis was aided by a fine needle aspiration cytology instead of the costlier histopathological procedures, in a setting with limited resources.

Congenital self-healing reticulohistiocytosis with BRAF V600E mutation in an infant

Congenital self-healing reticulohistiocytosis (CSHR) is a rare disorder characterized by benign skin lesions with a tendency to self-heal. Multiple skin lesions are usually present in CSHR. It is very difficult to distinguish between CSHR and an invasive Langerhans cell histiocytosis. We present a case of a 5-month-old infant girl who had hypopigmented skin lesions distributed over her neck, thorax and torso. The skin lesions regressed spontaneously 2 months after the diagnosis of CSHR and the child has remained in complete remission without any sign of recurrence over a 2-year follow-up. BRAF V600E mutation was detected in lesional cells along with a low Ki-67 proliferative activity of about 6%. BRAF oncogene-induced senescence might contribute to a mechanism of self-regression in CSHR; however, the exact role of the somatic BRAF V600E mutation in CSHR remains to be determined.

Langerhans cell histiocytosis in children: History, classification, pathobiology, clinical manifestations, and prognosis

Langerhans cell histiocytosis (LCH) is an inflammatory neoplasia of myeloid precursor cells driven by mutations in the mitogen-activated protein kinase pathway. When disease involves the skin, LCH most commonly presents as a seborrheic dermatitis or eczematous eruption on the scalp and trunk. Evaluation for involvement of other organ systems is essential, because 9 of 10 patients presenting with cutaneous disease also have multisystem involvement. Clinical manifestations range from isolated disease with spontaneous resolution to life-threatening multisystem disease. Prognosis depends on involvement of risk organs (liver, spleen, and bone marrow) at diagnosis, particularly on presence of organ dysfunction, and response to initial therapy. Systemic treatment incorporating steroids and cytostatic drugs for at least one year has improved prognosis of multisystem LCH and represents the current standard of care.

Dermatoscopy of Common Lesions in Pediatric Dermatology

The use of dermatoscopy to assist in the diagnosis of a variety of proliferative, pigmentary, inflammatory, infectious, congenital, and genetic cutaneous and skin appendage disorders is constantly increasing, as it is effective, affordable, noninvasive, and quick to perform.

Langerhans cell histiocytosis mimicking molluscum contagiosum: A case series

Langerhans cell histiocytosis (LCH) is a disorder characterized by accumulation of Langerhans-like cells in one or various organs. A correct staging work-up is essential since there are multiorgan presentations with a poor prognosis. We report three patients with LCH skin lesions mimicking molluscum contagiosum in association with both high and low risk organ involvement. This peculiar cutaneous presentation can be a clue for the diagnosis of LCH, a disease with potentially severe systemic involvement.

Congenital Langerhans cell histiocytosis presenting in a 27-week-gestation neonate

Langerhans cell histiocytosis is exceedingly rare in premature infants, and the few cases reported suggest a poor prognosis with systemic involvement. We present a case of Langerhans cell histiocytosis limited to a single cutaneous lesion, presenting in a 27-week-gestation infant, which is the youngest gestational age of reported Langerhans cell histiocytosis cases. The lesion showed spontaneous resolution by 41 weeks corrected gestational age, and systemic involvement was absent, demonstrating a mild course of skin-only Langerhans cell histiocytosis in a premature infant.

Cutaneous Hematolymphoid and Histiocytic Proliferations in Children

This article focuses on cutaneous hematopoietic neoplasms that are more likely to be encountered in the pediatric age-group and includes both lymphoproliferative and histiocytic disorders. The cutaneous hematologic disorders in children have a different epidemiologic profile to what is seen during adulthood. Although mycosis fungoides is the most frequent form of cutaneous lymphoma in adults, it is very rare in children. Because lymphoblastic leukemias and lymphomas are more frequent in the pediatric setting, cutaneous leukemic infiltrates are relatively common in this age-group. Similarly, histiocytic disorders are more common in children, particularly Langerhans cell histiocytosis and juvenile xanthogranuloma. Notably, the histiocytic disorders have undergone significant modifications on their nomenclature in the basis of the molecular characteristics that are present in them. A summary of the most frequent cutaneous hematopoietic disorders in children will be discussed further in this review.

High frequency of clonal IG and T-cell receptor gene rearrangements in histiocytic and dendritic cell neoplasms

The 2008 World Health Organization (WHO) diagnostic criteria of histiocytic and dendritic cell neoplasms from hematopoietic and lymphoid tissues no longer required the absence of clonal B-cell/T-cell receptor gene rearrangements. It is true that the clonal B-cell/T-cell receptor gene rearrangements have been identified in rare cases of histiocytic and dendritic cell neoplasms, such as those with or following lymphoma/leukemia or in some sporadic histiocytic/dendritic cell sarcomas, but the clonal features of such group of tumor are still not clear. Here we investigated the clonal status of 33 samples including Langerhans cell histiocytosis (LCH), Langerhans cell sarcoma (LCS), follicular dendritic cell sarcoma (FDCS), interdigitating dendritic cell sarcoma (IDCS) and histiocytic sarcoma (HS). Among them, twenty-eight cases were sporadic without current or past lymphoma/leukemia. Three cases were found with a past history of T-cell lymphoma, one case was followed by extraosseous plasmacytoma, and one case was found with diffuse large B-cell lymphoma (DLBCL). Our results showed that there was a high frequency of clonal IG and T-cell receptor gene rearrangements in these cases. Notably, 4 cases of LCH and 2 cases of FDCS showed both B and T cell receptor gene rearrangements concurrently. One case of FDCS synchronous with DLBCL showed identical clonal IGH in both tumor populations and clonal TCRβ in FDCS alone. No matter if the presence of clonal receptor gene rearrangements was associated with the tumor origin or tumorigenesis, it might serve as a novel tumor marker for developing target therapy.

Langerhans cell histiocytosis in children - a disease with many faces. Recent advances in pathogenesis, diagnostic examinations and treatment

Langerhans cell histiocytosis is a rare clonal disease characterized by the proliferation of CD1a-positive immature dendritic cells. The purpose of this article was to present an updated review of recent advances in the pathogenesis, clinical features, imaging and treatment of this disease. The discovery of oncogenic BRAF mutations and the presence of proinflammatory cytokines and chemokines confirmed the unusual characteristics of this disease. Currently, children with organ involvement who do not have a good response to chemotherapy and have neurodegeneration or diabetes insipidus are the most problematic patients. Further research is needed to improve the results of treatment.