Primary musculoskeletal Langerhans cell histiocytosis in children: an analysis for a 3-decade period

Skeletal staging in Langerhans cell histiocytosis: a multimodality imaging review

Evaluating the extent of skeletal disease in Langerhans cell histiocytosis (LCH) is a major predictor of patient outcome. Traditionally, whole-body skeletal staging consists of plain radiography and bone scintigraphy. However, more recently whole-body MRI has been shown to be accurate in detecting osseous and extra-osseous lesions, but no large-scale studies analysing its role within the diagnostic algorithm of LCH skeletal staging currently exist. In addition, FDG PET-CT provides useful information regarding disease activity and treatment response, but has an inherent radiation dose which is not ideal in children. Currently, radiographic skeletal survey remains the gold standard with cross-sectional imaging only performed for further characterisation. However, radiographs have shown a wide sensitivity range for skeletal staging and have clear limitations in detecting extra-skeletal disease, a crucial component of stratification in identifying 'at risk' organs. We aim to highlight the various appearances of bony LCH across all the imaging modalities for primary skeletal staging. We will also review the advantages, disadvantages, sensitivity and specificity of each, and establish their role in staging skeletal LCH. Recent studies using whole-body MRI have shown promising results, with radiographs and other modalities playing a more complementary role.

Langerhans cell histiocytosis in the occipital condyle: a case study and a brief review of the literature

We present a case study of a 5-year-old patient, who presented with left-sided torticollis. Due to persistence of problems, a CT and an MRI were made showing a single osteolytic lesion centred on right occipital condyle. After an open biopsy, histology confirmed it to be Langerhans cell histiocytosis (LCH). Torticollis or restricted range of motion is a presenting feature in 76% of children with LCH with cervical involvement. There remains much debate on the best treatment strategy. The clinical and radiological outcomes of the case study presented on this article support the treatment of LCH with chemotherapy in cases with solitary involvement of the occipital condyle.

Acetabular roof lesions in children: a descriptive study and literature review

Background

Acetabular roof lesions (ARLs) in children are uncommon and may involve a variety of diseases. The acetabular roof is the main weight-bearing area of the hip joint, and lesions affecting the acetabular roof lead to fluid accumulation in the hip joint, causing hip pain and claudication. Methods for diagnosing and treating ARLs and the prognosis after treatment are rarely reported. We present our experience in a group of children and teenagers with ARLs to retrospectively explore the clinical and imaging features and histopathological diagnosis and report the treatment methods and follow-up observations.

Methods

Patients with ARLs admitted to the Children’s Hospital of Chongqing Medical University from April 2011 to September 2018 were selected retrospectively. We collected the basic information of patients (name, sex, age), main symptoms and signs, results of various laboratory tests, treatment methods, and intraoperative observations through the hospital medical record system. We collected X-ray, computed tomography (CT), magnetic resonance imaging (MRI) and pathological examination data through the Picture Archiving and Communications System. Follow-up data were collected through an outpatient medical record system, telephone, and chat software (such as WeChat). We used descriptive methods to analyze the lesion structure and destruction mode based on the imaging findings and histopathological diagnosis.

Results

There were 14 ARL patients, including 6 with eosinophilic granuloma (EG), 5 with chronic osteomyelitis, 2 with bone cyst, and 1 with tuberculosis. One patient underwent percutaneous needle biopsy, 2 underwent open biopsy, and 11 underwent curettage; among them, 5 patients also underwent bone grafting. These lesions had no characteristic imaging findings, and the diagnosis was mainly based on histopathological examination. Most patients showed complete symptom resolution and good hip function at the 1-year follow-up.

Conclusion

ARLs are not common in children. The types of lesions are diverse and mostly benign, with EG being most common. Malignant tumors may also occur, such as Ewing’s sarcoma, non-Hodgkin’s lymphoma, metastases and neuroblastoma. CT and MRI can be helpful in diagnosing certain cases, but incisional biopsy is required in most cases.

Incidence and radiological pattern of eosinophilic granuloma: a retrospective study in a Chinese tertiary hospital

Background

The incidence and radiological patterns of eosinophilic granuloma (EG) in China is not clear. We described the incidence, presentation, and imaging characteristics of Chinese EG patients in a tertiary hospital.

Methods

A retrospective chart review was performed from January 2004 to October 2017 at a single tertiary general hospital. Seventy-six patients were pathologically identified as EG. Besides, 60 patients with preoperative imaging diagnosis of “EG” were analyzed to reveal the radiological patterns and their diagnostic power.

Results

Fifty-three male and 23 female EG patients with a mean age of 18.1 ± 16.7 years (range 1–58 years) were retrospectively included. Significant differences were observed in gender (male to female = 2.3:1) and age (the highest incidence at the age of 0~5 years) for EG. EG predominantly involved the skeletal system: flat bones (31.43%) > irregular bones (24.76%) > long bones (22.86%) > other organs (20.95%). No obvious relationships between season, biochemical markers, and EG incidence were observed. The common presenting symptoms were pain followed with local mass, and most patients underwent surgical resection. Among 60 imagingly diagnosed “EG” patients from April 2009 to October 2017, only 22 were with histological confirmation. The correct diagnosis rates were 37.1% (13 out of 35), 16.7% (5 out of 30), and 22.2% (8 out of 36) for plain radiography, computed tomography (CT), and magnetic resonance imaging (MRI), respectively.

Conclusions

Chinese EG has a varied presentation, age distribution, and gender difference. EG diagnosis is still based on biopsy or histopathology instead of imaging techniques.

Electronic supplementary material

The online version of this article (10.1186/s13018-019-1158-1) contains supplementary material, which is available to authorized users.

Imaging of Upper Limb Tumors and Tumorlike Pathology

Bone and soft tissue sarcomas are uncommon tumors that can occur within the upper extremity as well as elsewhere within the body. However, certain histopathological subtypes have increased affinity for the upper limb and even certain sites within the arm and hand. Other benign masses and tumor mimics, such as infection and traumatic lesions, are more common and imaging appearances can sometimes overlap with malignant lesions making diagnosis difficult. In this article, we explore the current options for imaging of these lesions as well as typical imaging appearances of the more common upper limb tumors.

The application of x-ray, computed tomography, and magnetic resonance imaging on 22 pediatric Langerhans cell histiocytosis patients with long bone involvement: A retrospective analysis

The studies focusing on x-ray, computed tomography (CT), and magnetic resonance imaging (MRI) in pediatric Langerhans cell histiocytosis (LCH) patients were still rare. Therefore, we aimed to evaluate the application of x-ray, CT, and MRI in pediatric LCH patients with long bone involvement.Total 22 pediatric LCH patients were included in this study. The diagnosis of LCH was confirmed by pathological examination. All patients were followed up for 3 years. X-ray, CT, or MRI was performed and the results were recorded for further analyses.Among 22 pediatric patients, x-ray (n = 20), CT (n = 18), or MRI (n = 12) were used to scan the lesion on long bones affected by LCH. Femurs (n = 13, 38.24%), tibia (n = 11, 32.35%), humerus (n = 5, 14.71%), and radius (n = 4, 11.76%) were the most frequently affected anatomic sites. Ovoid or round radiolucent lesions, aggressive periosteal reaction, and swelling of surrounding soft tissues were characteristic image of long bones on x-ray, CT, and MRI in pediatric LCH.Femurs, tibia, humerus, and radius were the most commonly affected long bones of pediatric LCH. The application of x-ray, CT, and MRI on long bones could help with the diagnosis of pediatric LCH.

Langerhans cell histiocytosis of bone in an adult: A case report

Langerhans cell histiocytosis (LCH) may clinically manifest in a variety of ways due to its ability to involve nearly every organ system. LCH may present as a single bone lesion, skin rash, or as invasive disseminated disease and occurs typically in the pediatric and adolescent population, affecting both males and females. Independent of its clinical presentation and severity, LCH lesions share the common histology of CD1a⁺/CD207⁺ dendritic cells along with an inflammatory infiltrate, and, based upon improved scientific understanding, is now classified as a myeloproliferative neoplasm. We present a case report of an adult diagnosed with LCH of the pelvis.

Langerhans Cell Histiocytosis: A Diagnostic Challenge in the Oral Cavity

Background

Langerhans cell histiocytosis (LCH) is a rare disorder of the reticuloendothelial system with unknown etiology. This report aims to present a case of LCH with diffuse involvement of the oral cavity and to raise awareness of the distinguishing features of this diagnostically challenging entity.

Case Report

A 26-year-old male patient presented with complaints of teeth mobility, intense pain, and difficulty in chewing. Intraoral and radiological examinations revealed generalized gingival hyperplasia and severe teeth mobility with widespread alveolar bone loss. Periodontal therapy was performed with no significant improvement. An incisional biopsy revealed Langerhans cells and positive reaction to S-100 and CD1, and the patient was diagnosed with LCH. The patient underwent systemic chemotherapy with vinca alkaloids and corticosteroids. Regression of gingival lesions, as well as significant decrease in mobility of the remaining teeth and severity of pain, was achieved during 12 months of follow-up.

Conclusion

The rarity and variable system involvement of LCH necessitate a multidisciplinary approach be carried out for accurate diagnosis, effective treatment, and an uneventful follow-up. Awareness of oral manifestations of LCH may aid clinicians greatly in reducing morbidity and mortality associated with this debilitating condition.

Evaluation of pituitary uptake incidentally identified on 18F-FDG PET/CT scan

The clinical significance of pituitary uptake on routine whole body ¹⁸F-fluorodeoxyglucose (FDG) positron emission tomography/computer tomography (PET/CT) is not completely characterized. We seek to assess the potential differential diagnosis/underlying etiology of pituitary FDG uptake incidentally identified on routine PET/CT scans. A total of 24,007 PET/CT whole body scans in recent 5 years were retrospectively reviewed. Patients with maximum standardized uptake value (SUVmax) > 4.1 in the pituitary glands were identified. Cases with a known history of pituitary disorders were excluded. Nineteen cases were identified with incidental pituitary FDG uptake which all had a final pathological diagnosis/clinical follow up. Among them, there were 9 primary pituitary tumors, with SUVmax ranging from 4.7 to 29.3 (13.6 ± 9.8); 3 metastatic malignancy with SUVmax ranging from 7.3 to 32.3 (16.0 ± 10.6); 3 Langerhans cell histiocytosis (LCH) with SUVmax ranging from 6.0 to 26.0 (15.0 ± 10.2); 1 pituitary lymphocytic hypophysitis with SUVmax of 4.7. Of note, 3 cases with SUVmax of 7.5,7.9 and 9.6 showed no relevant clinical symptoms with negative results on subsequent magnetic resonance (MR) and were counted as benign physiologic uptake. The most common differential diagnosis of incidental pituitary uptake on routine whole body PET/CT scans was primary pituitary tumors, followed by metastatic malignancy, Langerhans cell histiocytosis, and inflammatory lymphocytic hypophysitis. Of note, benign physiologic uptake without corresponding lesions could also occur in our population.

Usual and Unusual Manifestations of Familial Hemophagocytic Lymphohistiocytosis and Langerhans Cell Histiocytosis

Familial hemophagocytic lymphohistiocytosis (FHL) and Langerhans cell histiocytosis (LCH) are histiocytic diseases that occur most commonly in young children. Improvements in recognition and treatment have been substantial for both diseases in the past decade, although early and late morbidity continue to be major concerns. These two diagnoses behave differently, although the clinical spectra for both diseases are diverse and can lead to confusion and delays in diagnosis and treatment. This article focuses on the clinical and genetic spectrum of FHL as well as the clinical and treatment variations of LCH.

Approaches to treatment of unifocal langerhans cell histiocytosis: is biopsy alone enough?

BACKGROUND

Langerhans cell histiocytosis (LCH) is a variable disorder involving either single bone or multiorgan systems. The most effective treatment of unifocal osseous lesions is debated in the literature. This study describes the treatment approaches for LCH and demonstrates the effectiveness of biopsy in providing symptom resolution.

METHODS

Records of 61 patients diagnosed with LCH at a single institution over an 11-year period were reviewed. Thirty-nine patients with biopsy-confirmed diagnoses of unifocal osseous LCH were included in the analysis. At this institution, lesions are surgically treated by incisional biopsy, trocar biopsy, or curettage and grafting. Patients receive chemotherapy on a case-by-case basis, depending on the lesion location and size. A Kaplan-Meier analysis was used to compare time with symptom resolution across treatment groups.

RESULTS

In the 39 patients with unifocal osseous LCH, treatment approaches included incisional biopsy (n = 18, 46.15%), trocar biopsy (n = 8, 20.51%), incisional biopsy and chemotherapy (n = 8, 20.51%), and biopsy with bone grafting (n = 5, 12.82%). The median time from biopsy to symptom resolution was 5.43 weeks, with an average length of follow-up of 1.59 years. The median time to symptom resolution was 3.86 weeks with incisional biopsy, 5.43 weeks with biopsy and grafting, 5.64 weeks with trocar biopsy, and 16.57 weeks with biopsy and chemotherapy. Overall, there was a significant difference (P = 0.0262) in the time to symptom resolution across the different treatment approaches. Time to symptom resolution was significantly different between incisional biopsy and chemotherapy treatment compared with the incisional biopsy treatment (P = 0.0027), as well as biopsy with grafting treatment (P = 0.0264).

CONCLUSIONS

Symptom resolution occurred rapidly after biopsy and did not significantly differ among patients who received incisional biopsy, trocar biopsy, or biopsy with grafting. Unifocal osseous LCH likely does not require aggressive surgical or medical management. Biopsy alone both confirms the diagnosis and precedes a predictable resolution of symptoms.

LEVEL OF EVIDENCE

Level III, retrospective comparative therapeutic study.

Outcomes of children younger than 24 months with langerhans cell histiocytosis and bone involvement: a report from a single institution

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare disorder that ranges from single-system to disseminated multisystem disease. Patients younger than 24 months of age more commonly present with risk organ (liver, spleen, hematopoietic system, or lung) involvement at diagnosis and have a poor prognosis. Treatment approaches have changed over the last 25 years. Our goal was to describe the course and outcomes of patients younger than 24 months of age at diagnosis and identify the role of bone involvement in outcomes.

METHODS

We conducted a retrospective chart review of patients diagnosed with LCH at Children's Hospital Los Angeles from 1984 to 2010, focusing on 71 patients younger than 24 months of age at diagnosis.

RESULTS

Ten patients had single bone lesions at diagnosis and did well irrespective of therapy. The majority of patients (40/71 or 56%) had multiple bone lesions. Of the 37 patients with multisystem disease, 27 children (73%) had risk organ involvement. Fourteen patients with risk organ involvement received ≤ 6 months of initial chemotherapy with prednisone and vinblastine. Six of these patients had reactivation of the disease, and bone was the most frequent site of reactivation. Seven patients with risk organ involvement were treated with at least 12 months of chemotherapy. Only one of these patients had reactivation of the disease, and none died. The majority (7/10) of patients with risk organ involvement who progressed on therapy died despite multiple treatment regimens.

CONCLUSIONS

Patients younger than 24 months of age at diagnosis are more likely to have multiple bone lesions than older patients, supporting that a radiographic skeletal survey at the time of LCH diagnosis is important to evaluate the extent of bone involvement. Bones were the most common site for reactivation for all patients. As expected, subjects with risk organ involvement had better outcomes when treated with systemic chemotherapy for at least 1 year.

LEVEL OF EVIDENCE

As a retrospective review of all cases at our institution over a 26-year period, this article represents level IV evidence.

Diagnosis and management of langerhans cell histiocytosis

Langerhans cell histiocytosis is a rare group of disorders without a well-understood etiology. Known formerly as histiocytosis X, the disease has a wide spectrum of clinical presentations, including eosinophilic granuloma (solitary bone lesion), diabetes insipidus, and exophthalmos. It is also known by several eponyms, including Hand-Schüller-Christian disease when it manifests as a triad of cranial bone lesions and Letterer-Siwe disease when it is found in infantile patients with severely disseminated disease. Children aged 5 to 15 years are most commonly affected. Many of these patients initially present to orthopaedic surgeons, and misdiagnosis is frequent. To accurately diagnosis and treat these patients, the orthopaedic surgeon must be familiar with the clinical manifestations and pathophysiology of the disease as well as the treatment guidelines and outcomes for Langerhans cell histiocytosis.

Solitary Langerhans cell histocytosis of skull and spine in pediatric and adult patients

PURPOSE

Langerhans cell histiocytosis (LCH) is a rare neoplasm and has heterogeneous clinical presentation and behavior. We analyzed solitary lytic lesions of the skull and spine in pediatric and adult patients.

METHODS

Between 2001 and 2011, 42 patients underwent surgery for LCH. Skull and/or spine involvement were evident in 21 (63.6%) of the 33 pediatric patients and 8 (88.9%) of the 9 adults. The 21 pediatric patients showed the unifocal monosystemic lesions in 10, multifocal monosystemic in 4, and multisystemic in 7. The eight adults comprised seven unifocal lesions and one multifocal monosystemic lesion. Of these cases, we analyzed the clinical courses of solitary LCH of skull and spine in 10 pediatric patients and 7 adults.

RESULTS

The median age was 10.1 years (range: 1.1-14.1) in pediatric patients and 34.6 years (range: 26.1-52.0) in adults. The median follow-up was 3.1 years (range: 0.6-9.5). Total excision was done in 15 patients and biopsy in 2. Postoperative adjuvant chemotherapy was done in four pediatric patients and one adult, and comprised mass with dural adhesion (N = 2), skull base lesion (N = 1), atlas mass (N = 1), and vertebral lesion with soft tissue extension (N = 1). During follow-up, recurrence occurred in one pediatric patient who had a skull LCH with a dural adhesion. The patient experienced central diabetes insipidus and scapular pain due to pituitary stalk and scapula involvement 1.3 and 2.4 years later, respectively.

CONCLUSION

Even if the solitary lesions of skull and spine show a favorable clinical course, some patients could show aggressive behavior.

Resorption of PDLLA plates as a nidus for recurrent langerhans cell histiocytosis

Resorbable plating systems have been adapted into routine use for craniofacial reconstruction in children. After implantation in some patients, the area around the plates can develop palpable and visible fibrous capsules, with underlying bone resorption and a significant foreign-body giant cell reaction. The reaction is usually self-limited. We report a case in which Langerhans cell histiocytosis was resected, and then recurred at the sites of resorbing plate and screw placement in association with a foreign-body giant cell reaction.

Langerhans cell histiocytosis of bone in children: a long-term retrospective study

Langerhans cell histiocytosis is rare and frequently involves the bone. We retrospectively reviewed the orthopaedic aspects (symptoms, localizations, treatments) and the long-term outcome [disease status, overall survival (OS), event-free survival (EFS)] of 121 patients (June 1968-December 2009). The main symptom was local pain. The orthopaedic treatment was mainly conservative. The most frequent localization was osseous monofocal (62% of monosystemic diseases). Monosystemic and osseous monofocal localizations, treatment after 1991 (OS, P=0.007; EFS, P=0.03) and age older than 2 years (OS, P=0.003; EFS, P=0.001) were prognostic factors that were positively associated with survival. Oncologic treatment has improved over time, translating into better survival. A biopsy is often mandatory.

The usefulness of F-18 fluorodeoxyglucose positron emission tomography/computed tomography in patients with Langerhans cell histiocytosis

OBJECTIVE

Langerhans cell histiocytosis (LCH) has a wide spectrum of clinical manifestations, ranging from spontaneous resolution to rapid progression or death, with the risk of permanent consequences. F-18 FDG PET/CT has been used for assessment of LCH patients. However, its clinical implication has not been well elucidated, mainly due to very low incidence of LCH. The aim of this study was to evaluate the clinical usefulness of F-18 FDG PET/CT in LCH patients.

METHODS

A database of 12 patients (mean age 17.8 ± 17.9 years; 7 children, 5 adults) who were diagnosed histopathologically as LCH was retrospectively reviewed. Two patients underwent F-18 FDG PET/CT before and after therapy, 6 patients underwent only before therapy and 4 patients underwent only after therapy.

RESULTS

Nine (75.0%) and 3 patients (25.0%) had single-system (single site and multiple sites) and multisystem involvements, respectively. Pretreatment SUV(max) of patients with multisystem or multiple site involvement of a single-system was significantly higher than that of patients with single site involvement of a single-system (3.29 ± 2.52 vs. 1.63 ± 0.52, p = 0.025). One patient showed multisystem risk organs (lung and bone marrow) involvement. In 2 patients, F-18 FDG PET/CT detected additional active LCH lesions not identified on conventional imaging modalities. In follow-up F-18 FDG PET/CT scans, complete resolution was identified in 2 patients and reactivation in another 2 patients.

CONCLUSIONS

Results of this study suggest that F-18 FDG PET/CT is useful for identification of active lesions, stratification of disease stages, monitoring of therapeutic response, and detection of reactivation in LCH patients.

Langerhans cell histiocytosis: 40 years' experience

OBJECTIVES

Our study analyzes 40 years' experience with pediatric Langerhans cell histiocytosis patients.

MATERIALS AND METHODS

Between June 1968 and December 2009, 121 patients (79 males, 42 females; median age 4.13 y) were diagnosed at our center (74% monosystemic disease; 26% multisystemic), treated according to current protocols. We evaluated the response, the survival, and the neuroendocrinological sequelae.

RESULTS

Overall survival (OS) for all patients was 93% at 10 years from diagnosis, event-free survival (EFS) 77%. OS for patients younger than 2 years and older than or equal to 2 years was 82% and 97% (P = 0.003); EFS 48% and 87% (P = 0.001). OS for patients diagnosed before and after April 1, 1991 was 84% and 98% (P = 0.007), EFS 66% and 85% (P = 0.03). OS for monosystemic and multisystemic disease was 100% and 71% (P < 0.001); EFS 88% and 45% (P < 0.001). OS for "risk" patients (involvement of bone marrow, spleen, liver, lungs) and "low-risk" patients was 50% and 94% (P = 0.007), EFS 37% and 54% (P = 0.06). Fourteen patients developed diabetes insipidus, 7 patients growth hormone deficiency, 2 hypothyroidism, and 1 neurodegeneration.

CONCLUSIONS

Our study confirms improvement of pathogenetic knowledge and treatment over the last 20 years. Age at diagnosis older than or equal to 2 years and standardized treatment are associated with improved prognoses. Multisystemic involvement, especially with "risk" organs seem to be correlated to a worse outcome.

Does adjunctive chemotherapy reduce remission rates compared to cortisone alone in unifocal or multifocal histiocytosis of bone?

BACKGROUND

Langerhans cell histiocytosis (LCH) is a rare disorder that can affect almost any organ, including bone. Treatment options include local corticosteroid infiltration in isolated bone lesions and oral corticosteroids and chemotherapy in multifocal bone lesions. Several studies show local corticosteroid injection in unifocal bone lesions heal in more than 75% of patients with minimal side effects. Therefore, it is unclear whether chemotherapy adds materially to the healing rate.

QUESTIONS/PURPOSES

We therefore compared overall survival, remission rate, and recurrence rate in patients with bone LCH treated with chemotherapy and corticosteroids or corticosteroids alone.

METHODS

We retrospectively reviewed the records of 198 patients with LCH since 1950. Median age at diagnosis was 5 years, male-to-female ratio was 1.33, and the most frequent symptom was local pain (95%). We recorded the disease presentation, demographics, treatment, and clinical evolution of each patient. Minimum followup was 4 months (median, 24 months; range, 4-360 months).

RESULTS

The survival rate of the systemic disease group was 76.5% (65 of 85) while the survival rate in the unifocal and multifocal bone involvement groups was 100% at a median 5-year followup. All patients with unifocal bone involvement and 40 of 43 (93%) with multifocal bone involvement had complete remission. One of 30 patients with multifocal bone involvement treated with chemotherapy and oral corticosteroids did not achieve remission whereas two of six receiving only corticosteroids did not achieve remission.

CONCLUSIONS

Our observations suggest intralesional corticosteroid injection without adjunctive chemotherapy achieves remission in unifocal bone LCH but may not do so in multifocal single-system bone involvement. Larger series would be required to confirm this observation.

LEVEL OF EVIDENCE

Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

The child with bone pain: malignancies and mimickers

Bone pain in children is common. The cause may be as benign as growing pains or as life-threatening as a malignancy. When a cause cannot be established by laboratory tests, physical examination or patient history, imaging of the affected body part is often obtained. Distinguishing benign from malignant processes involving the bones of children, based on imaging findings, can be challenging. The most common benign conditions that mimic pediatric bone tumors on imaging are Langerhan's cell histiocytosis and osteomyelitis. In this review, the current literature regarding the pathology and imaging of these conditions is reviewed. Benign conditions are compared with the most common pediatric bone tumors, Ewing sarcoma and osteosarcoma, with an emphasis on clinical and imaging features that may aid in diagnosis.

A case of langerhans cell histiocytosis with anal fistula

Langerhans cell histiocytosis (LCH) is an uncommon clinically heterogeneous disorder characterized by the proliferation and accumulation of Langerhans cells with local infiltration of tissues and organ destruction. LCH takes many clinical forms, affecting different systems and different sites in the same system with variable outcomes. Bone, skin, lymph node, pituitary, liver, lung, bone marrow and spleen involvement can be seen in patients with LCH. Involvement of the perianal site is rare. In this article, a 16-month-old boy with multiple organ involvement including skin, liver, lung, and bone is presented. Aside from these systemic involvements, he also had a simple anal fistula. According to our best knowledge, this case of LCH with anal fistula is only the second to be reported in childhood. We would like to emphasize that LCH may be associated with anal fistula; therefore, we suggest that patients with LCH should be examined for this condition.