Hematopoietic stem cell transplantation in Langerhans cell histiocytosis: case report and review of the literature

Adult pulmonary Langerhans cell histiocytosis revealed by central diabetes insipidus: A case report and literature review

Langerhans cell histiocytosis (LCH) is a rare systemic and heterogeneous disease secondary to proliferation and diffuse infiltration of immature CD1a-positive dendritic cells, also known as Langerhans cells. LCH affects predominantly paediatric patients and is rarely diagnosed in adulthood. Despite its worldwide prevalence, most reported cases are found in the Japanese population. There is no consensus regarding treatment strategy due to the low incidence of this disease and the diversity of symptoms that appear. An integrative literature review was conducted based on the PubMed database using MeSH terms 'Langerhans', 'histiocytosis' and 'adult'. The present report describes a case of a successfully treated LCH-induced central diabetes insipidus (uncommon presentation in adult patients) as well as an updated review of current evidence published on this matter.

A rare disorder mimics otitis media: Langerhans cell histiocytosis of the temporal bone in a child with interstitial pulmonary fibrosis

Langerhans cell histiocytosis (LCH) is a rare disease ranging from a benign to a rapidly fatal condition affecting young children predominantly, and is characterized by an abnormal clonal proliferation of Langerhans cells. We report a case of a 3-year-old child presenting with a 1-year history of otorrhea and otorrhagia followed by a 6-month history of postauricular swelling in the right ear. Imaging demonstrated a large mass of organized tissue. A biopsy was conducted, and the diagnosis of LCH was confirmed by histopathological and immunohistochemical examination. The child was treated with a 12-month course of vinblastine chemotherapy with prednisolone. No clinical evidence of recurrence was noticed after 3 years of follow-up. This rare case highlights the importance for otolaryngologists to keep LCH in mind for differential diagnosis in very young patients with symptoms and signs suggestive of acute mastoiditis or chronic otitis media.

Haploidentical parental hematopoietic stem cell transplantation in pediatric refractory Langerhans cell histiocytosis

Children with MS-LCH that fail to respond to conventional chemotherapy have poor outcomes. HSCT represents a potential salvage approach. It has been applied in over 50 cases in recent years. HSCT can achieve greater disease control than chemotherapy, but it carries a high risk of transplant-related mortality; thus, the haploidentical parental HSCT is used infrequently in pediatric refractory LCH. We report the first successful haploidentical parental HSCT, with no T-cell depletion, in two girls, aged 26 months and five months, with refractory MS-LCH. The mothers were donors with 5/6 and 4/6 HLA matches, respectively. The conditioning regimen included busulfan + cyclophosphamide + etoposide + antithymocyte-globulin ± fludarabine; the GVHD prophylaxis was based on cyclosporine + methotrexate ± mycophenolate-mofetil ± zenapax. In both cases, the stem cells were sourced from peripheral blood and BM, which included CD34+ cells (13.17 × 10(6)/kg and 40.23 × 10(6)/kg, respectively). These patients survived and showed no signs of disease activity in 54- and 44-month post-HSCT follow-ups. Our results indicated that, for patients that fail chemotherapy delivered early in the disease, but do not show organ dysfunction progression, it may be possible to achieve successful haploidentical parental HSCT with a strong myeloablative regimen.

Histiocytic disorders: recent insights into pathophysiology and practical guidelines

The Histiocytoses are defined as non-malignant disorders due to abnormal accumulation and behavior of cells of the mononuclear phagocytic system. The best known histiocytoses, Langerhans cell histiocytosis (LCH), and hemophagocytic lymphohistiocytosis (HLH), each with an estimated incidence of 1/50,000 to 1/150,000, are sufficiently "common," complex and costly, to constitute an important problem in medical practice. At the same time, LCH, HLH and an array of other and more rare histiocytoses are sufficiently uncommon that most physicians lack the experience to diagnose, let alone care for patients with these conditions. The pathophysiology of most of the histiocytoses is unknown and, in the case of the widely-disseminated and potentially fatal forms, treatments to date have been variably effective and sometimes highly toxic. MAS has been reported to occur in association with almost any rheumatic disease, it is by far most common in the systemic form of Juvenile Idiopthic Arthritis (SoJIA). It is now recognized that MAS bears a close resemblance to Hemophagocytic Lymphohistiocytosis or HLH, and MAS is recognized as the major fatal complication of soJIA.