Histopathological maturation in juvenile xanthogranuloma: a blueberry muffin infant mimicking aleukemic leukemia cutis.

Juvenile xanthogranuloma (JXG) is usually identified by Touton giant cells, so their absence can complicate diagnosis. We encountered a case of non-typical neonatal JXG lacking Touton giant cells, which was difficult to differentiate from aleukemic leukemia cutis because of overlapping histopathological characteristics. A 1 month-old girl presented with a blueberry muffin rash and multiple 1-2 cm nodules within the subcutaneous and deeper soft tissues. Blood tests revealed pancytopenia. The initial nodule biopsy showed mononuclear cell infiltration, suggestive of mature monocytes or histiocytes, but no Touton giant cells. Bone marrow examination showed no evidence of leukemia. Despite worsening of the rash, pancytopenia, and weight gain over the following month, the results of the second biopsy remained consistent with the initial findings. Consequently, we provisionally diagnosed aleukemic leukemia cutis and initiated chemotherapy. After two courses of chemotherapy, the pancytopenia improved, but the nodules only partially regressed. A third biopsy of the nodule was performed to evaluate the histological response, and revealed Touton giant cells, confirming the diagnosis of JXG. In conclusion, distinguishing non-typical JXG from aleukemic leukemia cutis is challenging. This case highlights the importance of multiple biopsies and the potential for histopathological maturation.

Systemic juvenile xanthogranuloma: A systematic review.

OBJECTIVE: To perform a systematic review to investigate the available literature regarding systemic juvenile xanthogranuloma (SJXG) and report the population characteristics, clinical manifestation, therapy, and outcome. REVIEW METHODS: A search of PubMed, Embase, and Cochrane Library for all articles published between 1981 and 2022 was performed with variations and combinations of the following search terms: extracutaneous, visceral, systemic, and juvenile xanthogranuloma (JXG). Data extracted included demographics, organ involvement, treatment, outcome, and permanent sequelae. RESULTS: A total of 103 articles encompassing 159 patients met the inclusion criteria. The median onset age was 9 months, with a male predominance (61%). The distribution of major involved organs varied by age, and younger onset age was associated with more organ involvement. The most commonly involved site was the central nervous system (CNS) (40.9%), followed by the liver (31.4%), the lung (18.9%), and the eye (18.2%). At the termination of follow-up, 93 patients (58.5%) were alive with no disease, 56 (35.2%) were alive with disease, and 10 (6.3%) were dead of disease. There was a significant difference in outcome between patients with and without spleen involvement (p = .0003), and patients with spleen involvement suffered a higher risk of death. Permanent sequelae mainly comprised CNS symptoms and ocular manifestations. CONCLUSIONS: SJXG can involve varying numbers and combinations of extracutaneous sites. There is no standard therapy for SJXG and clinicians should choose individualized therapy modalities.

[Glaucoma secondary with juvenile xanthogranuloma in children:a case report].

A 4-month-old boy was admitted to the hospital after his parents noticed fog in his right eye for 27 days. Physical examination revealed multiple light brown macules on the skin. The intraocular pressure (IOP) of the right eye was 34.4 mmHg (1 mmHg=0.133kPa) and the corneal was enlarged and edema while the aqueous humor was cloudy with blood in the right eye. Yellow peripheral anterior synechia was seen on the temporal and inferior iris. Ultrasound biomicroscopy (UBM) showed extensive adhesion closure of the anterior chamber angle and the local thicken iris with the nodule. No obvious abnormality was observed in the left eye. It was confirmed as juvenile xanthogranuloma by skin lesion biopsy. IOP was normal after systemic and local therapy with corticosteroids and local IOP lowering medication. Follow up 35 months, IOP is normal without medication.

Histiocytic Disorders of Childhood.

Histiocytic disorders of childhood represent a wide spectrum of conditions that share the common histologic feature of activated or transformed "histiocytes." Langerhans cell histiocytosis (LCH) is the most common, with an incidence of approximately 5 per million children. LCH may be difficult to distinguish from more ubiquitous causes of skin rashes, bone pain, or fever. Current chemotherapy fails to cure more than 50% of children with multifocal disease, and treatment failure is associated with increased risks of long-term sequelae. Somatic activating mitogen-activated protein kinase (MAPK) pathway-activating mutations (most often BRAFV600E) have been identified in hematopoietic precursors in patients with LCH. Opportunities to improve outcomes with targeted therapies are under investigation. Juvenile xanthogranuloma (JXG) and Rosai-Dorfman disease (RDD) are less common than LCH and are distinguished by specific histologic and clinical features. Recurrent MAPK pathway gene mutations are also identified in JXG and RDD. In many cases, these conditions spontaneously resolve, but disseminated disease can be fatal. Although there has been historic debate regarding the nature of these conditions as inflammatory versus neoplastic, LCH, JXG, and RDD are now considered myeloid neoplastic disorders. In contrast, hemophagocytic lymphohistiocytosis (HLH) is clearly a disorder of immune dysregulation. HLH is characterized by extreme immune activation driven by hyperactivated T cells. HLH arises in approximately 1 child per million and is nearly universally fatal without prompt recognition and immune suppression. Outcomes of treated children are poor, with approximately 60% survival. Emapalumab, which targets interferon-γ signaling, was recently approved for patients with recurrent or refractory HLH, and additional cytokine-directed therapies are under investigation.

Juvenile xanthogranuloma in neurofibromatosis type 1. Prevalence and possible correlation with lymphoproliferative diseases: experience of a single center and review of the literature.

Abstract: Neurofibromatosis type 1 (NF1), is a rare genetic disorder that may involve almost every organ system in the body such as cutaneous, ophthalmologic and central and peripheral nervous system. Cutaneous findings are usually the first sign of the disease. In this study, we investigate the real prevalence of xanthogranulomas juvenile (JXG) and possible correlation with lymphoproliferative diseases. This is a retrospective study conducted on a population with NF1 followed by February 1983 to February 2022 at the "Sapienza" University of Rome, Italy. We investigate the real prevalence of juvenile xanthogranuloma in NF1 and possible correlation with lymphoproliferative diseases. JXG was present in 39 cases (3.1%). JXG is more frequent in NF1 than in the general population while the possible association with lymphoproliferative diseases in NF1 remains controversial.

Juvenile and adult xanthogranuloma: A 30-year single-center experience and review of the disorder and its relationship to other histiocytoses.

BACKGROUND: Juvenile xanthogranuloma (JXG) is the most common type of non-Langerhans cell histiocytosis whose cell of origin, etiology and pathogenesis are not fully understood. We aimed to provide an update on histopathologic and immunophenotypic profile of this well-characterized entity whose relationship to the other histiocytoses has received renewed attention in light of recent molecular genetic studies. MATERIALS AND METHODS: A retrospective review of all the cases with the pathologic diagnosis of "xanthogranuloma" was performed on our archives from 1989 to 2019. RESULTS: A total of 525 patients with 547 lesions diagnosed as JXG were identified with the median age of 4.5 years, a male predominance (M:F ratio 1.3:1) and a predilection for the head and neck region (40.8%). Cutaneous lesions comprised 76.8% cases and another 15.7% presented within soft tissues. The most common non-soft tissue, extracutaneous lesions included the brain (2.6%), and lungs (1.8%). Three basic histopathologic patterns were identified: early classic (EJXG) (14.2%), classic (CJXG) (45.3%), and transitional JXG (TJXG) (40.5%). Multinucleated giant cells, either Touton or non-Touton, were most frequently present in CJXG followed by TJXG. Mitosis was rare (<1/10 high-power field) among different patterns. There was an association among the patterns and lymphocytic infiltrates (P = 0.036), and presence of Touton or non-Touton giant cells (P < 0.001 for both) but not for mitotic count (P = 0.105) or eosinophilic infiltrates (P = 0.465). Additionally, there was a correlation between age groups and presence of non-Touton giant cells (P = 0.012) but not for Touton cells (P = 0.127). We have demonstrated that immunophenotypic expression of the lesion was not associated with age at diagnosis nor morphologic pattern: factor XIIIa 192/204 (94.1%), CD11c 75/77 (97.4%), CD4 82/84 (97.6%), CD68 200/201 (99.5%), CD163 15/15 (100%), CD1a 1/110 (0.9%), S-100 48/152 (31.6%), CD31 15/21 (71.4%), and vimentin 104/105 (99.0%). CONCLUSION: We have documented in a substantial series of cases of JXG that there is a correlation between one of the three basic histopathologic patterns with age at diagnosis, but with a consistent immunophenotype among the three patterns. Considering sensitivity and specificity rates, we suggest that a combination of CD11c, CD4, CD1a and either CD163 (preferred) or CD68 stains provides more specific diagnostic yield in the differentiation of JXG from other histiocytic disorders. JXG is also discussed in terms of its relationship and distinction from other similar histiocytic disorders in the context of MAPK/ERK pathway mutations.

Juvenile xanthogranulomas in Asian children.

Juvenile xanthogranuloma (JXG) is the most common non-Langerhans cell histiocytic disorder. It can rarely be associated with systemic involvement. There is a paucity of literature on JXG in Asian children. We aim to describe the epidemiology, clinical features, systemic associations, histological features and outcome of a cohort of Asian children with JXG, and review the literature on the condition. We retrospectively reviewed the demographic, clinical and histological data of patients less than 16 years of age, diagnosed with JXG at our tertiary pediatric hospital between January 2002 and April 2019. A total of 147 children with JXG were identified, with a slight male preponderance of 53.1%. The median age of the onset was 15.5 months, with 69.4% presenting before 2 years of age. There was no racial predilection. The most frequently involved site was the head and neck region (44.2%). The majority of patients (76.2%) presented with a solitary lesion. Spontaneous resolution was documented in 57.7% of our patients with mean duration to resolution of 18.8 months. The proportion and speed of resolution did not differ in children with single or multiple lesions. No ophthalmologic complications were detected in our study cohort. JXG in children is generally limited to the skin and is rarely associated with systemic involvement, including the eye. Unless clinically indicated, the results from our study does not support routine screening for juvenile myelomonocytic leukemia, eye or systemic complications, even in the setting of multiple cutaneous JXGs.

FEATURES OF DIAGNOSIS AND ADVERSE COURSE OF NEONATAL JUVENILE XANTHOGRANULOMA: CASE REPORT.

The work describes a case of rare neonatal systemic juvenile xanthogranuloma with an initial damage of the scalp, limbs, back and abdomen, multiple damages of the parenchyma of both lungs, spleen and liver with the development of a severe form of congenital cholestatic hepatitis. The diagnosis was established on the basis of histopathological and immunohistochemical examination of the skin nodules. The child on the background of therapy under the Langerhans cell histiocytosis III program achieved a partial response, which was manifested by a reduction of granulomatous formations on the skin, elimination of liver failure, but retained hepatosplenomegaly, specific lesions of the lung parenchyma, liver, and left kidney. Against the background of cytostatic therapy, the patient developed secondary pancytopenia, perianal ulcerative-necrotic dermatitis with lesions on buttocks, stomatitis, protein-energy deficiency, acute liver failure. coagulopathy, disseminated intravascular coagulation syndrome, acute renal failure, respiratory failure of III degree, cardiovascular insufficiency of III degree, pulmonary edema, cerebral edema, cerebral coma of II-III degree, enterocolitis, intestinal paresis. Despite multicomponent intensive care, the child's condition progressively deteriorated, and the patient died. The aspects of differential diagnosis of neonatal systemic juvenile xanthogranuloma are discussed.

Refractory Extracutaneous Juvenile Xanthogranuloma With Multiple Intracranial Nodular Lesions Successfully Treated With 2-Chlorodeoxyadenosine.

Juvenile xanthogranulomatosis (JXG) is a rare histiocytic disease that is usually limited to the skin, but some JXG cases involve other organs. JXG involving the central nervous system (CNS) is rare and its treatment is inadequate. The optimum treatment for refractory JXG involving the CNS remains unknown. We report here a case of refractory pediatric extracutaneous JXG (extra-JXG) involving the CNS with multiple intracranial masses treated with 2-chlorodeoxyadenosine resulting in achievement of long-term complete remission. 2-Chlorodeoxyadenosine, with favorable CNS penetration in the cerebrospinal fluid, is apparently an effective treatment for extra-JXG and systemic JXG (sJXG) with CNS involvement.

Iris Juvenile Xanthogranuloma Presenting with Hypopyon.

PURPOSE: To report a case an iris juvenile xanthogranuloma presenting with hypopyon. CASE REPORT: A 45-day-old infant was referred to our clinic for unilateral hypopyon. Slit-lamp examination revealed a 2 mm hypopyon in the left eye while visible areas of the iris were normal. Fundus examination was normal. Topical corticosteroids and antibiotics were initiated. The hypopyon regressed to 0.5 mm after 2 weeks of treatment. The now visible peripheral iris revealed an inferotemporal yellow-brown iris mass. Clinical findings were consistent with juvenile xanthogranuloma of the iris. The patient was referred to the pediatrics department which revealed no systemic involvement. Two months after total regression of hypopyon, the baby presented with a 3 mm spontaneous hyphema causing 50 mmHg intraocular pressure. The patient was followed with topical corticosteroids and antiglaucomatous drops until the hyphema was resolved. CONCLUSION: ocular involvement, which is the most common extracutaneous 15 manifestation of juvenile xanthogranuloma, should be considered in the differential diagnosis of hypopyon and/or hyphema in young children.

Juvenile xanthogranuloma in Noonan syndrome.

Noonan syndrome (NS) is one of the common RASopathies. While the clinical phenotype in NS is variable, it is typically characterized by distinctive craniofacial features, cardiac defects, reduced growth, bleeding disorders, learning issues, and an increased risk of cancer. Several different genes cause NS, all of which are involved in the Ras/mitogen-activated protein kinase (Ras/MAPK) pathway. Juvenile xanthogranuloma (JXG) is an uncommon, proliferative, self-limited cutaneous disorder that affects young individuals and may be overlooked or misdiagnosed due to its transient nature. A RASopathy that is known to be associated with JXG is neurofibromatosis type 1 (NF1). JXG in NF1 has also been reported in association with a juvenile myelomonocytic leukemia (JMML). As RASopathies, both NS and NF1 have an increased incidence of JMML. We report a 10-month-old female with NS who has a PTPN11 pathogenic variant resulting in a heterozygous SHP2 p.Y62D missense mutation. She was found to have numerous, small, yellow-pink smooth papules that were histopathologically confirmed to be JXG. In understanding the common underlying pathogenetic dysregulation of the Ras/MAPK pathway in both NS and NF1, this report suggests a possible molecular association for why NS individuals may be predisposed to JXG.

Neonatal systemic juvenile Xanthogranuloma with Hydrops diagnosed by Purpura skin biopsy: a case report and literature review.

BACKGROUND: Systemic juvenile xanthogranuloma is a very rare disease typically presents as skin lesions with yellow papules or nodules and is sometimes fatal. We report a case of congenital neonatal systemic juvenile xanthogranuloma with atypical skin appearance that made the diagnosis difficult. CASE PRESENTATION: A preterm Japanese female neonate with prenatally diagnosed fetal hydrops in-utero was born with purpuric lesions involving the trunk and face. Since birth, she had hypoxemic respiratory failure, splenomegaly, anemia, thrombocytopenia, coagulopathy, and was transfusion dependent for red blood cells, fresh frozen plasma, and platelets. Multiple cystic lesions in her liver, part of them with vascular, were detected by ultrasound. A liver biopsy was inconclusive. A skin lesion on her face similar to purpura gradually changed to a firm and solid enlarged non-yellow nodule. Technically, the typical finding on skin biopsy would have been histiocytic infiltration (without Touton Giant cells) and immunohistochemistry results which then would be consistent with a diagnosis of systemic juvenile xanthogranuloma, and chemotherapy improved her general condition. CONCLUSIONS: This case report shows that skin biopsies are necessary to detect neonatal systemic juvenile xanthogranuloma when there are organ symptoms and skin eruption, even if the skin lesion does not have a typical appearance of yellow papules or nodules.

Fatal Disseminated Multiple Intracranial Juvenile Xanthogranuloma without Cutaneous and Other Organ Involvement: A Rare Case Report.

INTRODUCTION: Juvenile xanthogranuloma (JXG) is a disorder of histiocytic proliferation that affects young children and usually presents as spontaneously regressing cutaneous lesions. JXG with systemic involvement is a rare entity associated with significant morbidity and mortality. Intracranial solitary lesions are uncommon, and when comorbid with multiple lesions of the central nervous system in young children, it has an extremely worse prognosis. CASE PRESENTATION: We have reported here an unusual case of a 6-year-old boy who initially presented with the complaints of headache, vomiting, seizure, and speech disorder without cutaneous and other organ involvement and a neurological tendency to sleep. Acute hydrocephalus was detected in his brain CT. As an emergency intervention, ventriculo-peritoneal shunt operation was performed on the patient. His postoperative MRI revealed a disseminated intracranial disease involving the extensive dural, sellar-suprasellar region, the orbit, and the brain parenchyma. The patient accordingly underwent a pterional approach for open biopsy and for the mass tissue diagnosis. Histopathology reports were consistent with JXG. Unfortunately, the patient succumbed to the disseminated disease within 2 months of the JXG diagnosis. CONCLUSION: JXG is a disorder that usually affects the skin. Intracranial lesion can be simple or have multiple involvement. This is a rare case of fatal disseminated multiple intracranial JXG without cutaneous and other organ manifestations. The presentation as a sellar-suprasellar, extensive dural, orbit, and parenchymal involvement at the time of diagnosis is unusual and rarely described in the literature.

Successful Salvage Treosulfan-Based Megachemotherapy With Allogeneic Stem Cell Transplantation in Nonsyndromic, Therapy-Resistant Disseminated Juvenile Xanthogranuloma: A Case Report.

Juvenile xanthogranuloma (JXG) is a rare histiocytic disorder classified as non-Langerhans cell histiocytosis; although it is usually a benign and self-limiting disease, it can be fatal in some cases, especially with systemic dissemination. We present a case report of a boy with therapy-resistant disseminated JXG who was treated with systemic chemotherapy and received 3 allogeneic hematopoietic stem cell transplantations (allo-HSCTs) from an unrelated donor. The post-transplant period was complicated by acute graft vs host disease and lymphoproliferative disease caused by Epstein-Barr virus. Currently, almost 7.5 years after the first transplantation, the boy is in complete remission with full donor chimerism and without symptoms of JXG. The presented data confirm rare observations that allo-HSCT can lead to durable remission of systemic JXG, which warrants its use in life-threatening, therapy-resistant subtypes of disease.

Solitary juvenile xanthogranuloma of the hypopharynx. Clinico-pathologic study in a child with ß-Thalassemia Major and Cutaneous Mastocytosis.

Juvenile Xanthogranuloma (JXG), the most common pediatric non-Langerhans cell histiocytosis, may rarely occur in association with Neurofibromatosis (types 1 and 2), Juvenile Myelomonocytic Leukemia and Cutaneous Mastocytosis (CM) and, morphologically, mimics Erdheim-Chester Disease tissue lesions and ALK-positive histiocytosis. We describe a 4-year-old girl with Beta-Thalassemia Major who developed an hypopharyngeal BRAFV600E- and ALK-negative JXG and CM. JXG has been rarely reported in the aerodigestive tract and in association with CM. In this molecular era, knowledge of genetic heterogeneity of JXG and clinical scenarios in which it may develop is essential for the appropriate diagnosis and treatment of each individual patient.