Sinus histiocytosis with massive lymphadenopathy: presentation as giant granuloma annulare and detection of human herpesvirus 6

Orbital histiocytosis; From A to Z

PURPOSE

Histiocytosis is one of the most challenging diseases in medical practice. Because of the broad spectrum of clinical manifestations, systemic involvements, unknown etiology, and complex management, different types of histiocytosis are still a big question mark for us. Orbital histiocytosis is characterized by the abnormal proliferation of histiocytes in orbital tissues. It could affect the orbit, eyelid, conjunctiva, and uveal tract. Orbital histiocytosis can cause limited eye movement, proptosis, decreased visual acuity, and epiphora. In this study, we review the novel findings regarding the pathophysiology, diagnosis, and treatment of different types of histiocytosis, focusing on their orbital manifestations.

METHOD

This review was performed based on a search of the PubMed, Scopus, and Embase databases or relevant published papers regarding orbital histiocytosis on October 9th, 2023. No time restriction was proposed, and articles were excluded if they were not referenced in English.

RESULTS

391 articles were screened, most of them being case reports. The pathophysiology of histiocytosis is still unclear. However, different mutations are found to be prevalent in most of the patients. The diagnostic path can be different based on various factors such as age, lesion site, type of histiocytosis, and the stage of the disease. Some modalities, such as corticosteroids and surgery, are used widely for treatment. On the other hand, based on some specific etiological factors for each type, alternative treatments have been proposed.

CONCLUSION

Significant progress has been made in the detection of somatic molecular changes. Many case studies describe various disease patterns influencing the biological perspectives on different types of histiocytosis. It is necessary to continue investigating and clustering data from a broad range of patients with histiocytosis in children and adults to define the best ways to diagnose and treat these patients.

A case report of epileptic seizures caused by Rosai Dorfman disease followed by a literature review

RATIONALE

Rosai Dorfman disease is a rare benign histiocytoproliferative disorder that occurs in the intracranial area, which occurrs typically in lymph nodes. Extrapnodal Rosai Dorfman disease rarely develops in the central nervous system and is often a focal lesion based on the dura. Based on imaging and clinical symptoms, RDD may be misdiagnosed as meningioma, and some lesions can also occur in the brain parenchyma. In the case of benign disease, the final diagnosis is made by pathological tissue diagnosis. For chronic diseases, progression may be chronic or remitting and relapsing.

PATIENT CONCERNS

A 54-years-old man was hospitalized after experiencing paroxic convulsions and being unconsciousness. A head magnetic resonance imaging demonstrates a strip of lesions in the right parietal lobe. No obvious abnormality is found in the laboratory data.

DIAGNOSES

We diagnosed meningioma of right parietal lobe and secondary epilepsy, and prescribed oral sodium valproate to treat him.

INTERVENTIONS

The lesion is located in the right parietal lobe on neuroimaging prior to surgery, which was taken for immunohistochemical examination.

OUTCOMES

If it is found that immunohistochemistry reveals histiocytes are positive for CD68, S-100, but negative for CD1a, it is identified as RDD. For patients who are seizure-free following surgery, symptomatic management is used. Following parietal lesion resection, patients are seizure-free during the follow-up period (44 months).

LESSONS

Basing on studying and summarizing relevant literatures, RDD is described in the report in terms of its diagnosis, pathology, treatment, and clinical outcome, in order to improve the diagnosis and identification of intracranial RDD by physicians.

Histiocytic disorders

The historic term 'histiocytosis' meaning 'tissue cell' is used as a unifying concept for diseases characterized by pathogenic myeloid cells that share histological features with macrophages or dendritic cells. These cells may arise from the embryonic yolk sac, fetal liver or postnatal bone marrow. Prior classification schemes align disease designation with terminal phenotype: for example, Langerhans cell histiocytosis (LCH) shares CD207+ antigen with physiological epidermal Langerhans cells. LCH, Erdheim-Chester disease (ECD), juvenile xanthogranuloma (JXG) and Rosai-Dorfman disease (RDD) are all characterized by pathological ERK activation driven by activating somatic mutations in MAPK pathway genes. The title of this Primer (Histiocytic disorders) was chosen to differentiate the above diseases from Langerhans cell sarcoma and malignant histiocytosis, which are hyperproliferative lesions typical of cancer. By comparison LCH, ECD, RDD and JXG share some features of malignant cells including activating MAPK pathway mutations, but are not hyperproliferative. 'Inflammatory myeloproliferative neoplasm' may be a more precise nomenclature. By contrast, haemophagocytic lymphohistiocytosis is associated with macrophage activation and extreme inflammation, and represents a syndrome of immune dysregulation. These diseases affect children and adults in varying proportions depending on which of the entities is involved.

Case of Generalized Tumor-Type Rosai-Dorfman Disease With Sarcoidosis-Like Histological Features and IgG4-Positive Plasma Cells

ABSTRACT

Rosai-Dorfman disease (RDD, also known as sinus histiocytosis with massive lymphadenopathy) is a rare and benign non-Langerhans cell histiocytosis. Skin biopsy usually shows nodular or diffuse dermatitis. Rosai-Dorfman cells (RDD cells) and emperipolesis are the key to diagnosis. RDD cells express S-100 antigen, CD68, CD163, α1-antitrypsin, α1-antichymotrypsin, and ham-56, whereas Langerhans cell markers such as CD1a and langerin are negative. We presented a case of a 55-year-old man with varying sizes of many dark red nodules and lumps over the face, trunk, and limbs for approximately 1 year but without systemic involvement. The results of the laboratory evaluations were notable for an increased level of serum IL-6 and serum IgG4. Histopathological examination showed a diffused dense nodular infiltration of "nude" epithelioid histiocytes with infiltration of minimal lymphocytes and plasm cells around the epithelioid nodules. Immunohistochemistry identified nodular histiocytes being stained strongly positive for S-100 and CD68 but negative for CD1a. Plasma cells showed focally positive for IgG, IgG4, and CD38 and with a ratio of IgG4/IgG >40%. Considering these findings, we believe that our case meets the diagnostic description of "cutaneous Rosai-Dorfman disease" and is, therefore, a rare case with clinical features of multiple tumor-like nodules, sarcoidosis-like histological features, and immunohistochemistry of IgG4-positive plasma cells.

Clinicopathological features, treatment approaches, and outcomes in Rosai-Dorfman disease

Rosai-Dorfman disease is a rare subtype of non-Langerhans cell histiocytosis. With the last major report published in 1990, there is a paucity of contemporary data on this disease. Our objective was to report the clinicopathological features, treatments and outcomes of patients seen at a tertiary referral center. Sixty-four patients with histopathological diagnosis of Rosai-Dorfman disease were identified from 1994 to 2017 (median age 50 years; range, 2-79). The median duration from symptom onset to diagnosis was seven months (range, 0-128), which was also reflected in the number of biopsies required to establish the diagnosis (median 2; range, 1-6). The most common presentation was subcutaneous masses (40%). Of the 64 patients, 8% had classical (nodal only) and 92% had extra-nodal disease (67% extra-nodal only). The most common organs involved were skin and subcutaneous tissue (52%), followed by lymph nodes (33%). Three patients had an overlap with Erdheim-Chester disease, which had not been described before. Two of these were found to have MAP2K1 mutations. Commonly utilized first line treatments were surgical excision (38%) and systemic corticosteroids (27%). Corticosteroids led to a response in 56% of the cases. Of those treated initially, 15 (30%) patients developed recurrent disease. The most commonly used systemic agent was cladribine (n=6), with 67% overall response rate. Our study demonstrates that Rosai-Dorfman disease has diverse clinical manifestations and outcomes. While this disease has been historically considered a benign entity, a subset of patients endures an aggressive course necessitating the use of systemic therapies.

A Study on Clinical Characteristics and Magnetic Resonance Imaging Manifestations on Systemic Rosai-Dorfman Disease

Background:

Rosai-Dorfman disease (RDD) is typically characterized by painless bilateral and symmetrical cervical lymphadenopathy, with associated fever and leukocytosis. The aim of the current study was to summarize the clinical features and imaging characteristics of RDD, in an effort to improve its diagnostic accuracy.

Methods

The study was analyzed from 32 patients between January 2011 and December 2017; of these, 16 patients had pathologically diagnosed RDD, eight had pathologically diagnosed meningioma, and eight pathologically diagnosed lymphoma. All patients underwent computed tomography and magnetic resonance imaging (MRI). Clinical features and imaging characteristics of RDD were analyzed retrospectively. The mean apparent diffusion coefficient (ADC) values of lesions at different sites were measured, and one-way analysis of variance and the least significant difference t-test were used to compare the differences between groups and draw receiver operating characteristic curves. The tumors were excised for biopsy and analyzed using immunohistochemistry.

Results:

The mean ADCs were (0.81 ± 0.10) × 10^-3 mm²/s for intercranial RDD, (0.73 ± 0.05) × 10^-3 mm²/s for nasopharyngeal RDD, (0.74 ± 0.11) × 10^-3 mm²/s for bone RDD, and (0.71 ± 0.04) × 10^-3 mm²/s for soft-tissue RDD. The optimum ADC to distinguish intracranial RDD from lymphoma was 0.79 × 10^-3 mm²/s (62.5% sensitivity and 100% specificity) and to distinguish meningioma from intracranial RDD was 0.92 × 10^-3 mm²/s (62.5% sensitivity and 100% specificity). Levels of C-reactive protein, erythrocyte sediment rate and D-dimer were significantly elevated (81%, 87%, and 75%, respectively). On immunohistochemistry, RDD was positive for both S-100 and CD68 proteins but negative for CD1a.

Conclusions:

Conventional MRI, combined with diffusion-weighted imaging and ADC mapping, is an important diagnostic tool in evaluating RDD patients. An accurate diagnosis of RDD should consider the clinical features, imaging characteristics, and the pathological findings.

Consensus recommendations for the diagnosis and clinical management of Rosai-Dorfman-Destombes disease

Rosai-Dorfman-Destombes disease (RDD) is a rare non-Langerhans cell histiocytosis characterized by accumulation of activated histiocytes within affected tissues. RDD, which now belongs to the R group of the 2016 revised histiocytosis classification, is a widely heterogeneous entity with a range of clinical phenotypes occurring in isolation or in association with autoimmune or malignant diseases. Recent studies have found NRAS, KRAS, MAP2K1, and ARAF mutations in lesional tissues, raising the possibility of a clonal origin in some forms of RDD. More than 1000 reports have been published in the English literature; however, there is a lack of consensus regarding approach for the clinical management of RDD. Although in most cases RDD can be observed or treated with local therapies, some patients with refractory or multifocal disease experience morbidity and mortality. Here we provide the first consensus multidisciplinary recommendations for the diagnosis and management of RDD. These recommendations were discussed at the 32nd Histiocyte Society Meeting by an international group of academic clinicians and pathologists with expertise in RDD. We include guidelines for clinical, laboratory, pathologic, and radiographic evaluation of patients with RDD together with treatment recommendations based on clinical experience and review of the literature.

Lymphoproliferative Syndromes Associated with Human Herpesvirus-6A and Human Herpesvirus-6B

Human herpesvirus 6A and 6B (HHV-6A and HHV-6B) have been noted since their discovery for their T-lymphotropism. Although it has proven difficult to determine the extent to which HHV-6A and HHV-6B are involved in the pathogenesis of many diseases, evidence suggests that primary infection and reactivation of both viruses may induce or contribute to the progression of several lymphoproliferative disorders, ranging from benign to malignant and including infectious mononucleosis-like illness, drug induced hypersensitivity syndrome/drug reaction with eosinophilia and systemic symptoms (DIHS/DRESS), and nodular sclerosis Hodgkin's lymphoma. Herein, we discuss the conditions associated with the lymphoproliferative capacity of HHV-6, as well as the potential mechanisms behind them. Continued exploration on this topic may add to our understanding of the interactions between HHV-6 and the immune system and may open the doors to more accurate diagnosis and treatment of certain lymphoproliferative disorders.

Histiocytoses: emerging neoplasia behind inflammation

Histiocytoses are disorders characterised by inflammation and the accumulation of cells derived from the monocyte and macrophage lineages, which results in tissue damage. Although they are often considered rare disorders with protean clinical manifestations, considerable advances in the understanding of their genetics have led to increased clinical recognition of these conditions, and fuelled further insights into their pathogenesis. In this Review, we describe insights into the cells of origin, molecular pathology, clinical features, and treatment strategies for some of the most common histiocytic disorders, including Langerhans cell histiocytosis, Erdheim-Chester disease, and Rosai-Dorfman disease. With the discovery of recurrent mutations affecting the mitogen-activated protein kinase and mTOR-AKT pathways in some of these histiocytoses, our understanding of these diseases has now evolved from the concept of a primary inflammatory condition to that of a clonal neoplastic disease. This understanding has led to the development of effective mechanism-based therapeutic strategies for patients with histiocytic diseases.

Extranodal right-optic nerve Rosai-Dorfman disease: A rare localization case report

BACKGROUND

Rosai-Dorfman is a rare disease that usually occurs in young adults. It is characterized with massive painless cervical lymphadenopathy and histiocyte proliferation. Isolated intracranial involvement is extremely rare. Our aim is to present a new rare case of extranodal Rosai-Dorfman disease that involved the right optic nerve in a 4-year-old boy.

CASE DESCRIPTION

A 4-year-old boy with right-sided convergent strabismus and amblyopia lasting for 1 year was treated at the Department of pediatric ophthalmology. Initial optical fundus examination was normal. Examination repeated after 1 year noted the atrophy of the optic nerve papilla. Visual evoked potentials of the right eye showed normal findings of prechiasmatic visual pathway with severe dysfunction of the right optic nerve. Magnetic resonance imaging (MRI) of the brain and orbits showed expansive changed and elongated right optic nerve with contrast enhancement, and smaller lesion in the right temporal operculum region visible in T2 and fluid-attenuated inversion recovery sequence. Through small eyebrow "keyhole" osteoplastic frontoorbital craniotomy the fusiform enlarged (to 2 cm) right optic nerve was identified, resected between the eyeball and optic chiasm, and transferred for pathohistological analysis. Early postoperative course had no complications. Histological, immunohistochemical, and ultrastructural analyses revealed extranodal Rosai-Dorfman disease. Right periorbital edema was verified on the 7^th postoperative day and regressed to supportive therapy. Control multi slice computed tomography (MSCT) and MRI of endocranium and orbits showed total tumor removal with no signs of complications.

CONCLUSION

Although rare, extranodular intracranial Rosai-Dorfman disease should be taken into account in the differential diagnosis of intracranial and intraorbital lesions, especially in the pediatric age group.

Cutaneous Rosai-Dorfman Disease: Comprehensive Review of Cases Reported in the Medical Literature since 1990 and Presentation of an Illustrative Case

Background:

The latest comprehensive review of primary cutaneous Rosai-Dorfman disease was published as part of an exhaustive survey of sinus histiocytosis with massive lymphadenopathy in 1990. Since then, much progress has been made in the understanding of malignant lymphoma and benign disorders of lymphoid and histiocytic origin.

Objective:

We reviewed cases of primary cutaneous Rosai-Dorfman disease published since 1990 and discuss their clinical and pathologic features, comparing them with cases of systemic Rosai-Dorfman disease.

Methods:

We conducted a search of the National Library of Medicine PubMed database for cases of cutaneous Rosai-Dorfman disease reported in the English-language medical literature since February 1990.

Results:

We identified 72 patients with cutaneous Rosai-Dorfman (female to male ratio 1:0.5). The gross appearance and number or distribution of lesions were highly variable. Abnormal laboratory data included peripheral blood cytopenias (10 patients) and increased gammaglobulin fraction (10 patients). The response to treatment was variable.

Conclusion:

Purely cutaneous disease without the characteristic lymphadenopathy is rare but has been increasingly reported in the literature. Compared with patients with systemic Rosai-Dorfman disease, patients with primary cutaneous Rosai-Dorfman disease are older, women are more commonly affected, and whites are more likely than blacks to be afflicted.

Uncommon histiocytic disorders: Rosai–Dorfman, juvenile xanthogranuloma, and Erdheim–Chester disease

Rosai–Dorfman disease (RDD), juvenile xanthogranuloma (JXG), and Erdheim–Chester disease (ECD) are non-Langerhans cell (non-LCH) disorders arising from either a dendritic or a macrophage cell. RDD is a benign disorder that presents with massive lymphadenopathy, but can have extranodal involvement. In most cases, RDD is self-limited and observation is the standard approach. Treatment is restricted to patients with life-threatening, multiple-relapsing, or autoimmune-associated disease. JXG is a pediatric histiocytosis characterized by xanthomatous skin lesions that usually resolve spontaneously. In a minority of cases, systemic disease can occur and can be life threatening. Juvenile myelomonocytic leukemia (JMML), as well as germline mutations in NF1 and NF2, have been reported in children with JXG. Recent whole-exome sequencing of JXG cases did not show the BRAF-V600E mutation, although 1 patient had PI3KCD mutation. ECD is an adult histiocytosis characterized by symmetrical long bone involvement, cardiovascular infiltration, a hairy kidney, and retroperitoneal fibrosis. Central nervous system involvement is a poor prognostic factor. Interferon-α is the standard as front-line therapy, although cladribine and anakinra can be effective in a few refractory cases. More than one-half of ECD patients carry the BRAF-V600E mutation. Currently, >40 patients worldwide with multisystemic, refractory BRAF-V600E+ ECD have been treated with vemurafenib, a BRAF inhibitor, which was found to be highly effective. Other recurrent mutations of the MAP kinase and PI3K pathways have been described in ECD. These discoveries may redefine ECD, JXG, and LCH as inflammatory myeloid neoplasms, which may lead to new targeted therapies.

Cutaneous Rosai-Dorfman Disease of the Face: A Comprehensive Literature Review and Case Report

PURPOSE

Cutaneous Rosai-Dorfman disease (C-RDD) is a rare, benign, non-Langerhans cell histiocytosis that can affect any skin area. The purpose of this study was to characterize C-RDD of the face through a literature review of published case reports of this lesion and present a new case of C-RDD.

MATERIALS AND METHODS

An English-language search of 3 databases (PubMed, Scopus, and EBSCO Search) was conducted for cases of C-RDD of any skin area that had been published since 1969. Repeated citations of the same article in more than 1 database were deleted. Cases of C-RDD with solely facial involvement or involving the face and other skin parts were included and analyzed. Details of C-RDD cases (demographic features, regional distribution, clinical presentation, treatment, and follow-up course) were methodically reviewed and collected in Excel spreadsheets. Simple statistical analyses were conducted using Excel.

RESULTS

The literature search yielded 578 published cases of C-RDD affecting any skin area; of these, 65 cases (11.2%) had facial skin involvement. The male-to-female ratio was 1:1.5, and the average age at presentation was 43.5 years (standard deviation, 12.4 yr). The racial distribution of facial C-RDD was, in descending order, 74.5% in Asians, 20% in Caucasians, and 5.5% in blacks. The most commonly affected facial skin regions were the cheeks and periorbital area, and most lesions were multiple in number and bilaterally distributed. The vast majority of facial C-RDD lesions presented as asymptomatic, nonulcerative, red, nodular plaques with durations ranging from 1 month to a few years. Many methods have been attempted for the treatment of facial C-RDD. However, the combined cure rate for all published treatment methods was only 28.6%. Surgical excision was the most effective treatment method, and corticosteroids were the least effective.

CONCLUSION

This article has tried to characterize facial C-RDD lesions for easier management by maxillofacial surgeons.

Uncommon histiocytic disorders: Rosai-Dorfman, juvenile xanthogranuloma, and Erdheim-Chester disease

Rosai-Dorfman disease (RDD), juvenile xanthogranuloma (JXG), and Erdheim-Chester disease (ECD) are non-Langerhans cell (non-LCH) disorders arising from either a dendritic or a macrophage cell. RDD is a benign disorder that presents with massive lymphadenopathy, but can have extranodal involvement. In most cases, RDD is self-limited and observation is the standard approach. Treatment is restricted to patients with life-threatening, multiple-relapsing, or autoimmune-associated disease. JXG is a pediatric histiocytosis characterized by xanthomatous skin lesions that usually resolve spontaneously. In a minority of cases, systemic disease can occur and can be life threatening. Juvenile myelomonocytic leukemia (JMML), as well as germline mutations in NF1 and NF2, have been reported in children with JXG. Recent whole-exome sequencing of JXG cases did not show the BRAF-V600E mutation, although 1 patient had PI3KCD mutation. ECD is an adult histiocytosis characterized by symmetrical long bone involvement, cardiovascular infiltration, a hairy kidney, and retroperitoneal fibrosis. Central nervous system involvement is a poor prognostic factor. Interferon-α is the standard as front-line therapy, although cladribine and anakinra can be effective in a few refractory cases. More than one-half of ECD patients carry the BRAF-V600E mutation. Currently, >40 patients worldwide with multisystemic, refractory BRAF-V600E(+) ECD have been treated with vemurafenib, a BRAF inhibitor, which was found to be highly effective. Other recurrent mutations of the MAP kinase and PI3K pathways have been described in ECD. These discoveries may redefine ECD, JXG, and LCH as inflammatory myeloid neoplasms, which may lead to new targeted therapies.

Rosai-Dorfman disease with diffuse gastrointestinal involvement

Rosai-Dorfman disease, formerly known as 'sinus histiocytosis with massive lymphadenopathy', is a rare self-limiting histiocytic proliferative disorder typically presenting early in life with cervical lymphadenopathy and nonspecific systemic symptoms. Although it is usually a nodal disease, extranodal lesions may be encountered in some cases. The gastrointestinal tract is uncommonly affected in Rosai-Dorfman disease and its diagnosis depends on clinical suspicion and careful histopathological examination of biopsy samples taken from involved gastrointestinal segments. Here, we report a case of atypical Rosai-Dorfman disease with systemic symptoms and diffuse gastrointestinal involvement that led to a diagnostic and therapeutic challenge.

Emperipolesis: an additional common histopathologic finding in H syndrome and Rosai-Dorfman disease

H syndrome is a recently described autosomal recessive disorder characterized by indurated, hyperpigmented, and hypertrichotic cutaneous plaques, mainly involving the lower abdomen and lower extremities. Associated systemic manifestations include hepatosplenomegaly, heart anomalies, hearing loss, hypogonadism, low height, and hyperglycemia. H syndrome is caused by mutations in the gene SLC29A3, which encodes hENT3, a member of the human equilibrative nucleoside transporter family. Histopathologically, cutaneous lesions of H syndrome consist of dermal and subcutaneous fibrosis with inflammatory infiltrate mostly composed of large histiocytes, some plasma cells, and scattered lymphoid aggregates. Recently, histopathologic and immunohistochemical studies have demonstrated that the immunophenotype of the histiocytes infiltrating the skin of a patient with H syndrome is similar to that of the lesions of Rosai-Dorfman disease. Furthermore, mutations in SLC29A3 gene have also been demonstrated in patients described as having an inherited form of Rosai-Dorfman disease, named Faisalabad histiocytosis or familial Rosai-Dorfman disease. We describe emperipolesis in the cutaneous lesions of a patient with H syndrome, further supporting the relationship between Rosai-Dorfman disease and H syndrome.

Cutaneous Rosai-Dorfman disease

Rosai-Dorfman disease is a self-limited benign disease. Rosai and Dorfman first described it in 1969, and the etiology of the disease remains unknown. Main manifestations are cervical adenopathy associated with fever, leukocytosis with neutrophilia and polyclonal gamaglobulinemia. Although the skin is the most common site of extra nodal disease, Rosai-Dorfman disease restricted to the skin is very rare with only a few cases described in the literature. This paper reports a rare case of cutaneous Rosai-Dorfman with skin as the sole site, and reviews the controversies of diagnosis and treatment.

Rosai-Dorfman disease (sinus histiocytosis with massive lymphadenopathy) of the pancreas: second case report

INTRODUCTION

Rosai-Dorfman disease (RDD), originally described as sinus histiocytosis with massive lymphadenopathy, is a rare histiocytic proliferative disorder with a distinctive microscopic appearance. It formerly was thought to be a process limited to lymph nodes, yet RDD has been documented to occur in many organ systems, notably the bone, skin, soft tissue, central nervous system, eye and orbit, and upper respiratory tract. The digestive system, however, is affected only exceptionally, with this being only the second documented case involving the pancreas.

CASE DESCRIPTION

In this case report, we present a case of a 63-year-old African-American female who was found to have a pancreatic head mass and right middle lobe pleural nodule during evaluation for obstructive jaundice.

DISCUSSION AND CONCLUSION

She underwent a Whipple procedure. Her pathology of both the pancreatic mass and RML lung wedge resection showed sinus histiocytosis with massive lymphadenopathy, along with extensive fibrosis intertwined with nodular mixed inflammatory infiltrate. The histiocytes characteristically showed "emperipolesis," in which lymphocytes had penetrated the cytoplasm and remained viable within the histiocytes (lymphocytes continued to have free movement in the histiocyte). In addition, the histiocytic cells were positive with S-100 protein and CD68, hallmarks of RDD. Although rare, Rosai-Dorfman disease should be considered in the differential diagnosis of patients presenting with pancreatic and/or lung nodules, especially when biopsy or cytology results report atypical inflammatory findings.

Sinushistiozytose mit massiver Lymphadenopathie (Rosai-Dorfman-Erkrankung)

Sinus histiocytosis with massive lymphadenopathy (SHML) is a rare, painless lymphoproliferative disorder of unknown origin with a usually benign course. About 40% of the patients show an extranodal involvement with skin being the most common site in 27% of these patients. We describe a patient with widespread disease involving the respiratory tract, kidneys and skin. Histopathology revealed the characteristic features of SHML with emperipolesis and immunohistochemical positivity of histiocytes for S100 and macrophage-associated antigens.

Cutaneous Rosai-Dorfman Disease

Cutaneous Rosai-Dorfman disease (CRDD) is a rare proliferative disorder of histiocytes with unknown etiology, broadly different from systemic Rosai-Dorfman disease. We present the largest series of CRDD, describing the clinical manifestation, histopathology, immunohistochemistry, and follow-up course of 25 cases in China. Clinically, 39 skin lesions in 25 patients were divided into 3 main types: papulonodular type (79.5%), indurated plaque type (12.8%), and tumor type (7.7%). Extremities were the most frequently involved, followed by trunk and face. None of the patients was found to have visceral organ involvement or lymphadenopathy. Microscopically, CRDD was characterized by scattering, clusters or sheets of large polygonal histiocytes intermingled with a florid, mixed inflammatory infiltrate. The most important feature was emperipolesis, which can be highlighted by S-100 protein stain. Patch and bandlike infiltrate of numerous mature plasma cells around glands and vessels was a constant finding in all lesions. Neutrophils existed in all cases to a variable degree with 2 cases forming microabscess. Four cases were remarkable for fibrosis, and xanthomatous change was observed in 2 cases. Coexistence of localized Langerhans cell histiocytosis and CRDD was interestingly found in case 7, which was evidenced by CD1a stain. Clinical follow-up in 22 patients, ranging from 2 to 55 months, indicated that surgical excision was the exclusive effective treatment for CRDD. Partial or complete spontaneous remission was achieved in 7 patients within 6 to 55 months. Owing to its favorable outcome, CRDD should be differentiated from a variety of benign and malignant lesions. Recognition of its wide clinical spectrum and histologic features combined with S-100 protein stain can help to establish the correct diagnosis.

Cutaneous Rosai-Dorfman disease: clinicopathological profiles, spectrum and evolution of 21 lesions in six patients

BACKGROUND

An uncommon histiocytosis primarily involving the lymph nodes, Rosai-Dorfman disease (RDD, originally called sinus histiocytosis with massive lymphadenopathy) involves extranodal sites in 43% of cases; cutaneous RDD (C-RDD) is a rare form of RDD limited to the skin. The clinicopathological diagnosis of C-RDD may sometimes be difficult, with different clinical profiles from those of its nodal counterpart, and occasionally misleading histological pictures. There have been few multipatient studies of C-RDD and documentation of its histological spectrum is rare.

OBJECTIVES

To identify the clinical and histopathological profiles, associated features, and the chronological changes of this rare histiocytosis.

METHODS

From 1991 to 2002, patients diagnosed as having C-RDD were collected in four academic hospitals. Clinical presentations, treatments, and courses of each case were documented. In total, 21 biopsy specimens obtained from these patients were re-evaluated and scored microscopically with attention to the uncommon patterns and chronological evolution both clinically and histologically.

RESULTS

We examined six patients with C-RDD, three men and three women. The mean age at the first visit was 43.7 years. The clinical presentations were mostly papules, nodules and plaques, varying with the duration and depth of lesions. Although the anatomical distribution was wide, the face was most commonly involved. Evolutional changes were identified clinically, as the lesions typically began with papules or plaques and grew to form nodules with satellite lesions and resolved with fibrotic plaques before complete remission. No patient had lymphadenopathy or extracutaneous lesions during follow-up (mean 50.5 months). At the end of follow-up, the lesions in four patients had completely resolved irrespective of treatment; two patients had persistent lesions. The histopathological pattern of the main infiltrate, the components of cells and the stromal responses showed dynamic changes according to the duration of lesions. The characteristic Rosai-Dorfman cells (RD cells) were found in association with a nodular or diffuse infiltrate in 15 lesions (71%). Four lesions (19%) demonstrated a patchy/interstitial pattern. One lesion (5%) assumed the pattern of a suppurative granuloma. RD cells were less readily found in these atypical patterns. Conspicuous proliferation of histiocytes associated with RD cells was found in three lesions, including xanthoma, localized Langerhans cell histiocytosis and xanthogranuloma. Along with lymphocytes, plasma cells were present in all lesions, often in large numbers with occasional binucleated or trinucleated cells. Variably found in the lesions were neutrophils (nine lesions, 43%) and eosinophils (13 lesions, 62%). The former occasionally formed microabscesses, while the latter were often few in number. Vascular proliferation was a relatively constant feature (90%). Fibrosis was found in 10 lesions (48%).

CONCLUSIONS

Our study further confirms that C-RDD is a distinct entity with different age and possibly race distributions from RDD. Compared with its nodal counterpart, C-RDD demonstrates a wider histopathological spectrum with different clinicopathological phases depending on duration of the lesions. Awareness of these features is helpful in making a correct diagnosis. The associations of C-RDD with other histiocytoses may have important implications for the pathogenesis of this rare histiocytosis.

Crystal Deposition in a Case of Cutaneous Rosai-Dorfman Disease

Rosai-Dorfman Disease (RDD) is an idiopathic reactive proliferation of distinctive histiocytes that have abundant cytoplasm and commonly exhibit intracytoplasmic ingestion of inflammatory cells (emperipolesis). The histiocytes are immunopositive for S100 protein and are typically associated with an infiltrate of lymphocytes, plasma cells, and neutrophils. The classic clinical presentation is massive enlargement of (usually) cervical lymph nodes with a histologic appearance that mimics exaggerated sinus histiocytosis. RDD can also involve extra-nodal sites and skin involvement is common either as part of disseminated disease or as a result of primary disease. We report an exceptional case of cutaneous RDD with crystal deposition in a young male presenting with skin nodules. Skin biopsy showed classic features of cutaneous RDD with the additional feature of conspicuous rhomboidal and needle-shaped crystals within the cytoplasm of many lesional plasma cells, histiocytes, and also in an extra-cellular location. The plasma cells were polyclonal by light chain immunostaining. Crystal deposition has not been reported to date in RDD and is likely a result of the reactive plasma cell proliferation.

Clinical and histopathologic spectrum of cutaneous Rosai-Dorfman disease in Taiwan

BACKGROUND

Cutaneous Rosai-Dorfman disease (RDD) is a rare entity of unknown origin and is not well documented, especially in Asian populations.

OBJECTIVE

The purpose of this study was to evaluate the clinical manifestation, diagnostic histopathology, clinical course, and response to treatment of cutaneous RDD in Taiwan.

MATERIALS AND METHODS

This study included 21 patients with cutaneous RDD who presented at our institution from 1995 to 2003. Pathologic examinations with both hematoxylin-eosin and immunohistochemical stains were reviewed, as were associated clinical features and therapeutic methods.

RESULTS

None of the 21 patients with cutaneous RDD had nodal lesions. The clinical manifestation was variable, but most commonly involved a central noduloplaque with satellite papules. One patient manifested as an ulcerated nodule, something not reported previously. Multifocal involvement only occurred in 4 patients. Concurrent involvement of uvea or vocal cord occurred in two patients. The most prominent histologic feature was a florid and mixed inflammatory infiltration. The phagocytosis of inflammatory cells into the cytoplasm of histiocytes, a process called "emperipolesis," is a characteristic finding of nodular RDD but usually only focally presented in cutaneous ones. Positivity for S-100 protein helped to confirm the diagnosis. The most effective treatment was surgical excision of solitary lesions. High-dose thalidomide (300 mg/d), but not low-dose, was effective to control the extensive cutaneous diseases in two patients. A total of 3 patients experienced spontaneous remission 1 to 2 years after diagnosis.

CONCLUSIONS

Cutaneous RDD appeared more frequently in Asian populations than in reports from Western countries. The incidence of multifocal involvement in this series is much lower than in other literature. Although treatment of disseminated cutaneous RDD is difficult, high-dose thalidomide (300 mg/d), which was effective in two patients in this series, may be helpful.

Five cases of cutaneous Rosai-Dorfman disease

Rosai-Dorfman disease (RDD), previously known as sinus histiocytosis with massive lymphadenopathy, is a benign, idiopathic histiocytic proliferative disorder. It commonly affects lymph nodes, but any organ of the body may be involved. Histological findings include characteristic large, pale, histiocytic cells (Rosai-Dorfman cells) exhibiting cytophagocytosis. Immunohistochemically, these histiocytes are positive for S-100 protein and CD68, but stain negatively for CD1a. On electron microscopy, Birbeck granules are absent. RDD limited to the skin is rare, less than 30 cases having been reported to date. We present five further cases of purely cutaneous RDD. Three presented as solitary nodules and one as a large, well-circumscribed plaque. The fifth patient, who was HIV positive, had a rosacea-like facial eruption.

Cutaneous rosai-dorfman disease is a distinct clinical entity

Rosai-Dorfman disease (RDD) is a rare but distinctive clinicopathologic entity of unknown etiology affecting lymph nodes as well as extranodal sites. Although cutaneous involvement in RDD is common, purely cutaneous disease is rare and not well documented. We report 22 patients with cutaneous and superficial subcutaneous RDD. The lesions presented as papules and nodules, often with discoloration (9/22) and frequent multifocality (13/22), without predilection for a specific site of the body. Age distribution was wide and ranged from 15 to 68 years, with a median of 43.5 years. Of the 17 patients for whom information on racial background was available, 7 were Asian, 8 were white, and 2 were black, with a marked female predominance (2:1). The lesions resolved in 6 of 13 patients for whom follow-up data were available, regardless of the treatment given. Lesions persisted or recurred in 7 patients. Histologically, the lesions are invariably characterized by a proliferation of polygonal S100-positive histiocytes showing emperipolesis and a mixed inflammatory infiltrate. This study characterizes the histologic spectrum of cutaneous RDD in regard to variation in the numbers of typical S100-positive histiocytes and emperipolesis, variation in the quality and quantity of the inflammatory response, and the degree of stromal fibrosis, which resulted in a strikingly storiform growth pattern in six lesions and a lobulated pattern in two lesions. Whereas the clinical as well as histologic appearance of the cutaneous and subcutaneous lesions in the purely extranodal forms of RDD is indistinguishable from that of systemic RDD, this study emphasizes that purely cutaneous RDD is a distinct clinical entity in regard to its epidemiology and remains localized to the skin even with long-term follow-up. Patients with purely cutaneous RDD are of an older age at onset of disease (median = 43.5 years), with a reversed male/female ratio. There are no significant systemic extracutaneous or serologic manifestations. Whereas systemic RDD is commonly seen in blacks and only rarely reported in Orientals, the majority of the patients in this series with purely cutaneous RDD are Asians and whites.

Cutaneous Destombes-Rosai-Dorfman disease: absence of detection of HHV-6 and HHV-8 in skin

BACKGROUND

We report three new cases of cutaneous Destombes-Rosai-Dorfman disease (DRDD). Two were skin-limited, and one was associated with systemic involvement. In all cases typical large S100 positive macrophages with emperipolesis were present, but different patterns were seen. A viral etiology has long been suspected in DRDD.

METHODS

Thus, all cases were investigated for presence of HHV-6 major capsid protein gene by polymerase chain reaction (PCR), and for presence of HHV-8 latency-associated nuclear antigen 1 by immunohistochemistry.

RESULTS

All results were negative. HHV-6 antibody tests were positive for IgG but not for IgM in one case. With regard to HHV-6, previous studies supplied inconclusive results while, to our knowledge, HHV-8 has never been investigated in DRDD.

CONCLUSION

This study suggests that HHV-8 is not involved in the pathogenesis of cutaneous DRDD. However, this should be confirmed by further studies. We can postulate three hypotheses in regard to HHV-6 role in DRDD pathogenesis: 1) its presence in lesionnal tissues is fortuitous, 2) HHV-6 plays a role in promoting more aggressive diseases and 3) various causes, including HHV-6, are implicated in the pathogenesis of DRDD.

Rosai-Dorfman disease complicated by autoimmune haemolytic anaemia: case report and review of a multisystem disease with cutaneous infiltrates

We report a patient with sinus histiocytosis with massive lymphadenopathy (Rosai-Dorfman disease) who presented with widespread nodal and extranodal involvement affecting the skin, orbits and nasal sinuses, complicated by the development of autoimmune haemolytic anaemia. The aetiology and pathogenesis of this multisystem disorder are unknown but are thought to represent a reactive histiocytic process to an infective agent rather than a neoplastic or other primary condition. Prognosis is generally good but clinical or laboratory evidence of immune dysfunction tends to predict a poorer outcome. We describe the clinical course of the patient and review the literature on this disease.

Sinus histiocytosis with massive lymphadenopathy and malignant lymphoma involving the same lymph node: a report of four cases and review of the literature

Sinus histiocytosis with massive lymphadenopathy (SHML), also known as Rosai-Dorfman disease, is a disorder of unknown cause. Rarely, patients with SHML also have malignant lymphoma, usually involving anatomic sites different from those involved by SHML We report four patients in whom SHML and malignant lymphoma were identified in the same lymph node biopsy specimen. The SHML in each case was present as a small focus, less than 1 cm. Immunohistochemical studies showed that the abnormal histiocytes were positive for S-100 and negative for CD1a. The malignant lymphomas included two cases of follicular lymphoma and two cases of Hodgkin's disease, nodular lymphocyte predominant type. The presence of SHML in these patients did not impact clinical decisions, and there was no evidence of SHML elsewhere. Thus, the presence of focal SHML associated with malignant lymphoma in these cases was an incidental histologic finding that seems not to have had any clinical significance.

Human herpesvirus 6 infects dendritic cells and suppresses human immunodeficiency virus type 1 replication in coinfected cultures

Human herpesvirus 6 (HHV-6) has been implicated as a cofactor in the progressive loss of CD4(+) T cells observed in AIDS patients. Because dendritic cells (DC) play an important role in the immunopathogenesis of human immunodeficiency virus (HIV) disease, we studied the infection of DC by HHV-6 and coinfection of DC by HHV-6 and HIV. Purified immature DC (derived from adherent peripheral blood mononuclear cells in the presence of granulocyte-macrophage colony-stimulating factor and interleukin-4) could be infected with HHV-6, as determined by PCR analyses, intracellular monoclonal antibody staining, and presence of virus in culture supernatants. However, HHV-6-infected DC demonstrated neither cytopathic changes nor functional defects. Interestingly, HHV-6 markedly suppressed HIV replication and syncytium formation in coinfected DC cultures. This HHV-6-mediated anti-HIV effect was DC specific, occurred when HHV-6 was added either before or after HIV, and was not due to decreased surface expression or function of CD4, CXCR4, or CCR5. Conversely, HIV had no demonstrable effect on HHV-6 replication. These findings suggest that HHV-6 may protect DC from HIV-induced cytopathicity in AIDS patients. We also demonstrate that interactions between HIV and herpesviruses are complex and that the observable outcome of dual infection is dependent on the target cell type.