17 July 2024

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Langerhans cell histiocytosis: Current concepts in dentistry and case report

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Langerhans cell histiocytosis (LCH), which is a rare granulomatous pediatric disease of unknown etiology, is characterized by the idiopathic proliferation and accumulation of abnormal and clonal Langerhans cells or their marrow precursors, resulting in localized, solitary or multiple destructive lesions. These lesions are most commonly eosinophilic granuloma, which are found in craniofacial bone structures such as the skull and mandible, skin and other organs. In children, the disease has a variable initial presentation, and the clinical course, prognosis and survival are unpredictable. The aims of this report were to present an LCH case in a girl aged 2 years, 8 months and her clinicopathological features, to describe the bucodental management provided, and to discuss special dental considerations of this disease.

Introduction

Langerhans cell histiocytosis (LCH), previously named histiocytosis X, is an uncommon hematological disease that predominantly affects infants and young children. LCH is characterized by a proliferation, infiltration and accumulation of a specific histiocyte, namely, the pathological Langerhans cell, which is considered to be a special type of dendritic mononuclear cell, within a variety of tissues and organs. Such dendritic mononuclear cells are derived from the bone marrow and possess important immunologic functions, particularly in antigen development of T-lymphocytes . The monoclonal infiltration of Langerhans cells, together with other immune effector cells, causes localized destructive tissue lesions as a result of the cellular infiltration, which replaces bone and invades skin, mucosa and internal organs .

The disease was firstly described in 1865 by Dr. Thomas Smith, who reported the case of a 4 years old child with impetigo and three large bone defects on the calvary. In 1868, the German physiologist Paul Langerhans observed several non-pigmented dendritic cells in the epidermis and mucous membrane, which he initially considered to be neuronal, and then corrected himself. Subsequently and independently of each other, Dr. Alfred Hand, Dr. Artur Schüller and Dr. Henry Christian described similar cases. In 1953, Dr. Louis Lichtenstein introduced the term ‘histiocytosis X,’ which characterized the disease as a proliferation of histiocytes of unclear etiology, and it was unknown whether it should be classified as a neoplastic, inflammatory or lipid disorder (9,10). In 1987, the Histiocyte Society was founded with the collaboration of several international research organizations; since then, the society has established diverse standards regarding the definition, classification and general management of LCH.

The pathogenesis of LCH remains unclear and poorly understood; however, according to Merglová et al., various etiologic factors have been proposed, such as neonatal infections, a skipped vaccination, exposure to solvents, and thyroid diseases. Approximately 200 new cases of LCH are diagnosed each year in the US, whereas in Western Europe, it is estimated that LCH occurs at a rate of 2 to 5 cases per million per year, primarily in children under the age of 15 (the incidence peaks between 1 year and 4 years, although some cases have been reported in newborns); 80% are Caucasian, and boys are affected more than girls, with a reported male:female ratio ranging from 2:1 to 4.6:1. Approximately 99% of patients are diagnosed with type I or II variety. Its incidence is approximately 10% that of acute childhood leukemias.

Search strategy

This review was based on a Medline-PubMed, Scopus, and Web of Knowledge searching, which was conducted to obtain papers published in English and Spanish languages, between June 1999 and December 2014, using the following MESH terms or key words, in different combinations: “Langerhans”, “histiocytosis”, “children”, “dental management”. We also conducted a ma-nual searching of relevant papers published in four major oral surgery journals (Journal of Craniomaxillofacial Surgery, Oral Maxillofacial Surgery, Oral Surgery Oral Medicine Oral Pathology Oral Radiology Endodontology, and Medicina Oral Patología Oral Cirugía Bucal), and three pediatric dentistry journals (Pediatric Dentistry, Journal of Clinical Pediatric Dentistry, International Journal of Paediatric Dentistry). Both electronic and manual searching yielded in total sixty-seven potentially relevant papers, based on the review of the corresponding abstracts. Then, following the full-text critical evaluation, thirty-three studies were finally included in the review.

Authors: Efraín Ramos-Gutiérrez, Francisco Alejo-González, Socorro Ruiz-Rodríguez, José-Arturo Garrocho-Rangel, and Amaury Pozos-Guilléncorresponding author

Source: https://www.ncbi.nlm.nih.gov/