Immunohistochemical and ultrastructural study of histiocytosis X and non-X histiocytoses

[Necrobiotic xanthogranuloma with scleroatrophic lichen associated with paraproteinemia]

Necrobiotic xanthogranuloma (Xn) with paraproteinemia is a histiocytoxanthomatosis (non-X histiocytosis) that affects the dermis and subcutaneous tissue of the face and less frequently the trunk and limbs. We present the case of a 58-year-old woman with a previous background of IgG (lambda) paraproteinemia and multiple autoimmune diseases, that associate clinically and histologically typical lesions of Xn on face, neck and limbs and of lichen sclerosus et atrophius (LEA) on skin and mucosae. The treatments performed were ineffective, the Xn lesions followed a chronic and progressive course with increased number, size and ulceration of them. The paraproteinemia has remained stable since it was diagnosed eight years ago. We have not found the association of Xn with paraproteinemia and SAL described in the literature. We review the characteristics of this rare disease and its possible pathogenic mechanisms.

Tracheal juvenile xanthogranuloma in a child

Juvenile xanthogranuloma is the most common form of non-Langerhans cell histiocytosis in children. It usually presents in the form of cutaneous lesions. Occasionally, the disease may affect other organs. Visceral forms are usually associated with cutaneous lesions, and are easily diagnosed. In isolated visceral occurrence, however diagnosis may prove difficult. Having the same spontaneous remission as cutaneous lesions, visceral lesions require treatment only in the case of serious dysfunction. We describe a case of isolated juvenile xanthogranuloma of the trachea, which has not previously been reported in children. The patient presented with serious respiratory symptoms that required immediate intervention.

Atypical generalized eruptive histiocytosis associated with acute monocytic leukemia

Histiocytoses are diseases caused by proliferation of either dendritic cells/Langerhans cells or of monocytes/macrophages. Generalized eruptive histiocytosis belongs to the cutaneous non-Langerhans cell histiocytoses and is a rare monocyte-macrophage proliferative disorder that usually follows a benign clinical course. We present the case of a 59-year-old man who presented with a 7-month history of progressively developing erythematous macules and slightly elevated papules widely distributed over the trunk, neck, face, and thighs. Ultrastructurally, no Birbeck granules were observed, and immunochemistry did not reveal any S-100 protein or CD1a antigen in any of the lesional cells, excluding Langerhans cell histiocytosis. In addition, the histiocytic infiltrate in the skin of our patient was shown to strongly express MS-1 high molecular weight protein, a marker described as highly characteristic for cutaneous non-Langerhans cell histiocytoses. Bone-marrow smear examination and flow cytometric analysis revealed monocytic leukemia. This is the second report of generalized eruptive histiocytosis associated with acute monocytic leukemia. We discuss the differential diagnoses of the clinical picture and stress that this benign cutaneous disorder may indicate an underlying hematologic malignancy.

Differential Expression of Markers in Extensive and Restricted Langerhans Cell Histiocytosis (LCH)

Langerhans cell histiocytosis (LCH) represents a poorly defined pathologic entity characterized by diverse clinical appearence and falling into two major categories namely a restricted and an extensive disease. Since the outcome and the course of the disease is variable, we postulated that this might be reflected by the phenotype of the Langerhans cells. We have selected 11 adult restricted cases and 10 extensive childhood cases and compared the phenotype of LCH cells by immunohistochemistry on paraffin sections. Morphometric analysis indicated a significantly higher expression of histiocytic (CD68, S-100, lysozyme) markers in the adult restricted cases compared to the extensive form of the disease. Both groups were equally positive for LCH marker CD1a and negative for T cell marker CD4. On the other hand, HLA-DR expression was significantly higher in LCH cells of the extensive childhood cases suggesting higher activation. These data suggest that LCH cells have a different phenotype in the extensive childhood and restricted adult LCH where the latter is characterized by a more differentiated histiocytic phenotype.

Update on juvenile xanthogranuloma: unusual cutaneous and systemic variants

Juvenile xanthogranuloma (JXG) is a well-recognized benign disorder of infancy and early childhood characterized by yellowish cutaneous nodules that spontaneously regress over months to years. In the vast majority of children, JXG is limited to the skin and requires no treatment. Over the past two decades, unusual cutaneous and systemic forms of JXG have been increasingly reported. JXGs have been discovered, usually unexpectedly, in every organ system of the body. Correct diagnosis is crucial to prevent unnecessary invasive diagnostic and therapeutic procedures. Unusual clinical and histological variants of JXG often require immunohistochemical studies and/or electron microscopy to establish the diagnosis. Nonlipidized, giant, intramuscular, subcutaneous, and clustered JXG are but some of the variants that are discussed in this article. The immunohistochemistry of JXG, current nosology, and hypotheses regarding the origins of JXG are also reviewed.

Non-Langerhans cell histiocytosis associated with lymphocyte-predominant Hodgkin's disease

We report a 74-year-old man who presented with a rash on the trunk showing clinical and histological features of non-Langerhans cell histiocytosis. Two years after presentation he developed weight loss, lymphadenopathy and hepatosplenomegaly; a diagnosis of lymphocyte-predominant Hodgkin's disease was made on lymph node biopsy. The cutaneous signs and lymphoma responded to chemotherapy. Taken in conjunction with previously published reports of associations between cutaneous histiocytoses and haematological malignancies, we recommend close observation of patients in whom a diagnosis of non-Langerhans cell histiocytosis is made.

Isolated intracranial Rosai-Dorfman disease: case report and literature review

Rosai-Dorfman disease, first described in 1969, is a rare idiopathic histioproliferative disease affecting the lymph nodes. Typical clinical features include bilateral painless lymphadenopathy, fever and polyclonal hypergammaglobulinemia. In approximately 43% of cases, extranodal sites may be involved and occasionally represent the initial or sole manifestation of the disease. Central nervous system manifestations are exceedingly rare, and only 17 cases have been recorded, among which there are merely seven isolated intracranial cases without concurrent nodal or other extranodal involvement. Herein, we report a 38-year-old male presenting with generalized tonic-clonic seizure and radiological findings indicative of meningioma. Complete physical examinations and laboratory surveys demonstrate the absence of involvement at other body sites. Microscopically, the lesion consists of proliferative histiocytes exhibiting emperipolesis coupled with the characteristic cytoplasmic staining against S-100 protein. The differential diagnosis of polymorphic inflammatory meningioma-mimicking masses is discussed, and a review of previously reported intracranial Rosai-Dorfman disease is presented.

Unusual expression of S-100 protein in histiocytic neoplasms

Twenty-nine cases of histiocytic neoplasms, some resembling juvenile xanthogranuloma (JXG) and others resembling reticulohistiocytoma (RH), were evaluated. Immunohistochemical stains were performed. In this series, seven cases were identified that expressed S-100 protein positive cells. The S-100 positive cells were predominantly large mononuclear and multinucleated histiocytes with eosinophilic cytoplasm, but also in some cases xanthomatous cells and Touton giant cells. These cells also expressed a positive reaction for vimentin, KP-1, and Factor XIIIa. There was no reactivity observed for monoclonal antibody 010(CD1a). A positive reaction for S-100 protein is conventionally accepted as a useful differentiating feature between histiocytosis X and non-X histiocytosis such as JXG and RH. The conflicting results of the immunohistochemical stains in the lesions we studied could be potential pitfalls in diagnosing histiocytic neoplasms.

Juvenile xanthogranuloma

Juvenile xanthogranuloma (JXG) is a benign, self-healing disorder characterized by solitary or multiple yellow-red nodules on the skin and, occasionally, in other organs. It is predominantly a disease of infancy or early childhood, although adults may also be affected. Histologically, JXG represents an accumulation of histiocytes lacking Birbeck granules (non-Langerhans cells), which can be differentiated from Langerhans cells by specific staining techniques. Affected persons have normal lipid metabolism. JXG is therefore classified as a normolipemic non-Langerhans cell histiocytosis. The patient's general health is not impaired and, in the absence of associated conditions, the prognosis is excellent. Diagnosis is readily made in typical cases, but may be more difficult in unusual variants.

Diagnosis and management of iris juvenile xanthogranuloma

BACKGROUND

Juvenile xanthogranuloma is a benign, self-limiting cutaneous disorder most commonly encountered during infancy. Approximately 10% of cases may develop ocular or adnexal involvement, most commonly in the iris.

METHODS

We review clinical and morphological features of four cases of iris juvenile xanthogranuloma that reflect the diagnostic and therapeutic spectrum.

RESULTS

Tissue diagnosis was confirmed in all cases; in one case, the disease was diagnosed with a skin biopsy and treated with local and systemic steroids, and its persistence in the iris was confirmed with a second tissue specimen obtained five months after systemic steroid treatment.

CONCLUSION

The diagnosis and treatment of juvenile xanthogranuloma may be straightforward, particularly in cases when the ocular lesion receives early attention and responds well to topical steroids, and when there is no hyphema. However, in other instances, this entity may be difficult to manage and may necessitate iris biopsy for diagnosis and radiation therapy for treatment.

[Histiocytosis]

Histiocytic disorders are a group of heterogeneous diseases. A logical classification can be based on the type of proliferating cell, either monocyte-macrophage or Langerhans/dendritic cell, and depends whether the proliferating cells are "reactive" or malignant. The classification now mainly depends on the histological examination. Regarding Langerhans cell histiocytosis (Hand-Schüller-Christian disease, Letterer-Siwe disease and eosinophilic granuloma), the diagnosis suspected on various clinical signs, is confirmed with histological examination showing infiltration with CD1 positive histiocytes disclosing intracytoplasmic Birbeck granules at electron microscopic examination. The prognosis depends on the patient's age at onset and the extension of the disease. Treatment is based on chemotherapy and corticotherapy.

Cellular composition of the angiofibromas in tuberous sclerosis

The angiofibroma of tuberous sclerosis is associated with a proliferation of dermal spindle cells that have been considered to be fibroblasts on the basis of a variety of techniques, although some cells have a glial appearance. This study of six angiofibromas demonstrated an increase in S100-positive, peanut agglutinin-negative spindle cells in the dermis in addition to increased numbers of epidermal melanocytes. The second major spindle cell population in the dermis proved to be dermal dendrocytes based on their expression of factor XIIIa. The number of these cells decreases in older patients, in whom the lesions were generally less cellular and more fibrotic. The angiofibroma of tuberous sclerosis is a hamartoma involving increased numbers of dermal dendrocytes, neurosustentacular cells, blood vessels, and melanocytes, in addition to collagen.

Langerhans cell (eosinophilic) granulomatosis. A clinicopathologic study encompassing 50 years

We summarize our experience with 238 cases of Langerhans cell granulomatosis (LCG), 198 of whom were followed for a median period of 10.5 years. Our patients did well unless overtreated, and no deaths were attributed to the disorder itself. The disease may appear in unifocal or multifocal form, and treatment is based on this fact. Virtually all patients recovered completely except for occasional residual orthopedic problems or residual diabetes insipidus. Several of the patients underwent subsequent pregnancies without difficulty. The granulomas primarily occur in bone, but lung, skin, and lymph nodal involvement is not uncommon. Involvement of thyroid, thymus, and other sites is rare. The hallmark of the disease is the accumulation of Langerhans cells (LCs). We review the pathology of LCG by histology, electron microscopy, and immunolabeling. LCs originally were identified in squamous epithelium, but these cells are part of the widespread system of dendritic cells. The latter cells, which arise from CD34+ progenitors, are specialized and efficient antigen-presenting cells for T-cell-mediated immunity. In LCG, however, the major associated cells are not T cells, but mature eosinophils: hence the original name eosinophilic granuloma. Confusion about terminology has been based upon the scanty and rather crude pathology reports in the original literature. The term histiocytosis X was meant to cover a spectrum of three diseases--eosinophilic granuloma, Hand-Schüller-Christian disease (HSC), and Letterer-Siwe disease (LS)--but HSC and LS have no basis in pathology and hence the terms are meaningless. The term HSC has become a synonym for multifocal eosinophilic granuloma (LCG). The term LS has been used in reporting a number of benign, malignant, or unknown conditions. We prefer the term LCG to avoid confusion with the term histiocytosis X because there is evidence that the LC is not a member of the mononuclear phagocyte system and hence not a tissue macrophage, and because the use of the term "histiocyte" has become a convenience in much of the literature when reporting incompletely understood diseases.

Oral mucosal Langerhans' cells

Langerhans' cells (LC) are dendritic, antigen-presenting cells present within the epithelium of skin and mucosa, including that of the oral cavity. This article reviews the literature on the phenotypic and functional features of oral mucosal Langerhans' cells, and speculates on other aspects by extrapolating from data on their epidermal counterparts.

Subcutaneous juvenile xanthogranuloma

A 1-month-old female infant was seen in consultation because of a congenital subcutaneous nodule, 2 x 3 cm in diameter, in the right retroauricular area. The nodule was surgically excised. Histologically, a large subcutaneous nodular mass was well delimited but not encapsulated. It consisted of a monomorphous sheet of foamy histiocytic cells with scattered eosinophils. Multinucleated giant cells were not found. The pure subcutaneous type of juvenile xanthogranuloma has been reported very rarely in the literature. The usual histological monomorphism of these cases, with only occasional eosinophils and lymphocytes and rare Touton giant cells, adds another diagnostic difficulty to their unusual clinical presentation.

Juvenile xanthogranuloma: a clinical, histopathologic and immunohistochemical study

Juvenile xanthogranuloma (JXG) is a benign histiocytic proliferation of uncertain histogenesis which usually resolves spontaneously. Histopathologically, classic lesions are characterized by diffuse proliferations of foamy histiocytes, many of which may be multinucleated (Touton cells), admixed with lymphocytes and eosinophils. Histologic variants of JXG, perhaps representing evolving lesions, may lack these typical histopathological features, showing diffuse infiltrates of non-foamy mononuclear histiocytes without Touton cells, posing problems in differentiation from other histiocytic or melanocytic proliferations. Immunohistochemically, JXG is characterized by variable expressions of several histiocytic markers as well as the absence of staining for S100 protein. To assess better the spectrum of histopathological and immunohistochemical features of JXG, we studied nine cases of classic or histologic variant of JXG. The cases were evaluated by light microscopy and with an extensive battery of antibodies. All 9 cases, regardless of their light microscopic appearance, showed markedly positive staining with histiocytic markers including CD68, HAM56, cathepsin B and vimentin, but did not stain for S100 protein. Antibodies to factor XIIIa stained positively in 8 cases while staining for other markers was variable. Our results suggest that the histiocytes in JXG lesions have macrophagic differentiation, probably representing a reactive process to an unknown stimulus.

A unique non-Langerhans cell histiocytosis with some features of generalized eruptive histiocytoma

A symmetric eruption of hundreds of coalescent small red macules and a few slightly elevated papules sparing the flexures was observed in a 73-year-old man. Light microscopic examination showed loose aggregates of small and large histiocytic cells. Electron microscopy showed an absence of Langerhans cell granules and lipid droplets. Features shared with generalized eruptive histiocytoma were the symmetry of the eruption sparing the flexures, the blue-red coloration, and the absence of lipid-containing foam cells and multinucleated giant cells. However, the primary occurrence of macules rather than papules or nodules, the tendency of the macules to coalesce, and the dimorphic histiocytoid infiltrate are not found in generalized eruptive histiocytoma. Nevertheless, immunohistochemistry confirmed that this unique condition is a form of MS-1+ cutaneous non-Langerhans cell histiocytosis.

Chorioretinal, iris, and ciliary body infiltration by juvenile xanthogranuloma masquerading as uveitis

Juvenile xanthogranuloma is a benign cutaneous disorder which occasionally involves the eye, orbit, and ocular adnexa in children. Iris and ciliary body manifestations are commonly seen, but retinal and choroidal lesions are exceedingly rare. We report a unique case of retinal, choroidal, iris, and ciliary body infiltration in a 12-year-old patient diagnosed by excisional biopsy of the iris. The diagnosis was confirmed by routine histology and oil-red-o staining. Immunohistochemistry revealed predominantly macrophages, monocytes, and T-helper lymphocytes. Unusual features of this case include the late age at diagnosis, posterior pole involvement, and lack of cutaneous lesions. The presence of cellular adhesion molecules and T lymphocytes implicate a lymphocyte-driven inflammatory process. Apolipoprotein A was the predominant apolipoprotein present within the foamy histiocytes. We also present a critical review of the literature.

An unusual case of non-Langerhans cell histiocytosis

A 28-month-old boy had firm, red nodules for 4 months that were mostly localized to the face. The eruption was preceded by conjunctivitis, eyelid edema, and swelling of the root of the nose. He also had dyspnea, anisocoria with areflexia, swelling of the parotid glands, and hepatosplenomegaly. A bone marrow aspirate showed 25% eosinophils. A skin biopsy specimen revealed a lymphohistiocytic infiltrate that involved the entire dermis. Most of the cells expressed antimacrophage markers; S-100 was negative. Electron microscopy showed poorly differentiated histiocytes without any specific marker. Steroid therapy induced complete clearing. Two years later, after several cutaneous recurrences, the patient is free of disease. We believe that this case represents a nodular, benign non-Langerhans cell histiocytosis with cutaneous lesions that differ from previously described histiocytopathies.

Histiocytosis: an unusual cause of dysphagia, hoarseness and stridor

We present a patient with established histiocytosis who developed dysphagia, retching, regurgitation, hoarseness and stridor. These symptoms were managed with carbon dioxide laser vaporization, electively on three occasions, and once as an urgent procedure, while awaiting radiotherapy, to control her airway. Histiocytosis is a rare cause of a number of otolaryngological syndromes, but there has been no previous record of this disease causing laryngopharyngeal symptoms. This paper discusses the classification of histiocytosis, and describes our management of this rare and intriguing case.

Immunohistochemical comparison of cutaneous histiocytoses and related skin disorders: diagnostic and histogenetic relevance of MS-1 high molecular weight protein expression

Twenty-nine cases of Langerhans cell histiocytosis (LCH), non-Langerhans cell histiocytoses (N-LCH), non-infectious granulomas, and fibroblast-related lesions were examined with a panel of monoclonal and polyclonal antibodies on freshly frozen tissue sections to characterize the macrophage phenotype of N-LCH syndromes. MS-1 high molecular weight extracellular protein, specific for sinusoidal endothelial cells and dendritic perivascular macrophages in normal human organs, was expressed by N-LCH cells but was not found in LCH cells, epithelioid cells in sarcoidosis, or palisading histiocytes in granuloma annulare. The subcellular location of MS-1 protein, i.e., cytoplasmic vs. peripheral/extracellular, allowed discrimination of small and large (foamy or multinucleated) N-LCH cells. MS-1-positive cells, which were found intermingled in cellular dermatofibromas but not in fibrous dermatofibromas, differed from MS-1-positive N-LCH cells by their dendritic morphology, and thus rather resembled their normal dermal counterparts. A preserved functional relationship of these two MS-1-positive cell types was indicated by the fact that N-LCH and cellular dermatofibromas were the only lesions found to be highly vascularized. As expected, CD1a showed high specificity for LCH, while CD34 was predominantly expressed by fibroblast-related lesions; in cellular dermatofibromas, CD34 and MS-1 expression partially overlapped. The other antigens tested showed non-specific or overlapping patterns of expression. In conclusion, assessment of MS-1 protein expression (in addition to assessment of CD1a and CD34) promises to be of diagnostic value in the discrimination of N-LCH from related skin disorders, and it may indicate a common differentiative pathway for most N-LCH disease entities.

Multiple juvenile xanthogranulomas without foam cells and giant cells

A 4-month-old boy had numerous nodular lesions. Microscopic findings revealed a histiocytic proliferation without foam cells and giant cells. Immunohistochemical studies showed that the histiocytes belonged to the monocyte-macrophage system and not to the Langerhans cell system. This case is an unusual variant of juvenile xanthogranuloma that, when congenital, may be difficult to differentiate from Hashimoto-Pritzker disease.

Expression of neuron-specific enolase immunoreactivity by cutaneous and extracutaneous Langerhans-cell histiocytoses ("X")

The immunohistochemical expression of Neuron-Specific Enolase (NSE) and of S100 protein was studied in 10 cases of cutaneous and 19 cases of extracutaneous Langerhans cell histiocytoses (LCH), including acute/proliferative forms (cutaneous Letterer-Siwe disease) and chronic/granulomatous forms (eosinophilic granuloma, Hand-Schüller-Christian disease). Of the LCH cases, 18 (62%) exhibited detectable NSE-immunoreactivity as compared to 82.8% for S100. NSE expression was found more frequently and intensely within acute (as compared to chronic) forms of LCH. This result lends further support to the cellular unicity of LCH, but also suggests some degree of heterogeneity among LCH cells. It can be speculated that NSE-expression is correlated with the proliferation/activation state of (abnormal) Langerhans cells.

Deep juvenile xanthogranuloma: a lesion related to dermal indeterminate cells

Juvenile xanthogranuloma (JXG) is considered to represent a lesion originating from histiocytes. Three cases of deeply located JXG and one case of cutaneous JXG were studied. One case with extensive mesenteric involvement presented with hypercalcemia and one case with liver involvement had hypergammaglobulinemia. Immunohistochemistry, electron microscopy, karyotyping, and DNA flow cytometry were used to determine the phenotype of the cells involved and to find further clues as to the histogenesis of these lesions. Immunohistochemically, all lesions studied expressed the CD1a antigen but showed no labeling for S-100 protein. The cells did not contain Birbeck granules. From these data it is suggested that the cells involved are of indeterminate dermal histiocyte lineage and that occurrence of deep located lesions of JXG may be due to migration of CD1 a-positive histiocytes.

Generalized papular xanthomatosis in mycosis fungoides

Xanthomas can occur in association with underlying lymphoproliferative disease, or they can result from lipid deposition in damaged or altered skin. We report a case of generalized papular xanthomas that developed in a patient with Sézary syndrome. The xanthomas were composed of foamy histiocytes that were shown by immunoperoxidase staining to be of the monocyte/macrophage lineage. Electron microscopic studies revealed lipid vacuoles, lysosomes, and myelin figures but no Birbeck granules, features that are consistent with a non-X histiocytosis. Generalized papular xanthomatosis has not been previously described in a patient with cutaneous T-cell lymphoma.

Generalized eruptive histiocytoma

The case is reported of a 56-year-old female who over 18 months developed a symmetrical eruption of hundreds of bluish-red papules, a small number of which have spontaneously resolved. The clinical and histopathological findings were compatible with the diagnosis of generalized eruptive histiocytoma. The ultrastructural findings in this case suggest that this condition which is in the non-X group of histiocytic disorders is closely related to histiocytosis X.

Generalized lichenoid juvenile xanthogranuloma

A generalized eruption of small, flat and shiny papules was observed in an otherwise healthy 6-month-old baby. The light and electron microscopical and immunohistological features of the self-healing lesions were consistent with juvenile xanthogranuloma and suggested an atypical lichenoid variant of this non-Langerhans cell histiocytosis.