[Neuro-Langerhans cell histiocytosis].
Langerhans cell histiocytosis (LCH) is a rare multisystemic disease. LCH is characterized by proliferation of myeloid progenitors with altered differentiation program and similar phenotypic features to epidermal dendritic cells termed Langerhans cell. LCH cells express CD1a+ and langerin and exhibit BRAF V600E mutation in ∼50% of cases. Neurological involvement or neuro-LCH is observed in 5 to 10% of cases. Three subtypes of neuro-LCH are individualized. The tumor type, accounting for 45% of neuro-LCH, affect mainly young adults. Tumor neuro-LCH is characterized by space occupying lesion(s) with contrast enhancement on MRI. Clinical symptoms are due to tumor brain location(s). Pathological examination of tumor neuro-LCH lesions reveals typical features of LCH. Treatment relies on surgical resection with/without chemotherapy. Degenerative neuro-LCH, accounting for 45% of cases, is usually revealed, mostly in children, by: (i) a cerebellar syndrome, (ii) a pyramidal syndrome, (iii) a pseubulbar palsy, and/or (iv) cognitive disorders. On MRI, several signs may coexist: (i) cortex atrophy, (ii) white matter T2 hyperintensities, and (iii) deep gray matter T1 hyperintensities. Pathological analysis of degenerative neuro-LCH lesions have been rarely performed and have never detected CD1a+ histiocytes but unspecific lesions (i.e. gliosis, neuronal loss and/or demyelination). Treatment of degenerative neuro-LCH patients is poorly standardized and poorly efficient. Functional rehabilitation and socio-educational care of these young patients are crucial. The mixed subtype of neuro-LCH combines clinico-radio-pathological characteristics of the first two first forms in the same patient, and represents 10% of neuro-HL. Neuro-HL, therefore, includes three very distinct entities with epidemiological, clinical, radiological and histological specific features requiring specific medical management.
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neurologie 2-Mazarin, Paris, France.
Loïc
L
Le Guennec
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neuroradiologie, Paris, France.
Nadine
N
Martin-Duverneuil
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neuropathologie, Paris, France.
Karima
K
Mokhtari
CHU de Tours, service de médecine nucléaire, Tours, France.
Maria
M
Santiago-Ribeiro
UGECAM-IdF, groupe hospitalier Pitié-Salpêtrière, service de médecine physique et de réadaptation, Paris, France.
Eléonore
E
Bayen
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de psychiatrie adulte, Paris, France.
Antoine
A
Del Cul
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neurologie 2-Mazarin, Paris, France.
Daniel
D
Delgadillo
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de médecine nucléaire, Paris, France.
Aurélie
A
Kas
AP-HP, groupe hospitalier Pitié-Salpêtrière, service d'endocrinologie et médecine de la reproduction, Paris, France.
Carine
C
Courtillot
AP-HP, groupe hospitalier Pitié-Salpêtrière, institut E3M, service de médecine Interne 2, Paris, France.
Julien
J
Haroche
AP-HP, groupe hospitalier Pitié-Salpêtrière, institut E3M, service de médecine Interne 2, Paris, France.
Fleur
F
Cohen
AP-HP, hôpital Trousseau, service d'oncologie hématologie pédiatrique, Paris, France.
Jean
J
Donadieu
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neurologie 2-Mazarin, Paris, France; Université Pierre-et-Marie-Curie - Paris 6, centre de recherche de l'institut du cerveau et de la moelle épinière (CRICM), UMRS 975, Paris, France; Inserm U 975, Paris, France; CNRS, UMR 7225, Paris, France.
Khê
K
Hoang-Xuan
AP-HP, groupe hospitalier Pitié-Salpêtrière, service de neurologie 2-Mazarin, Paris, France; Université Pierre-et-Marie-Curie - Paris 6, centre de recherche de l'institut du cerveau et de la moelle épinière (CRICM), UMRS 975, Paris, France; Inserm U 975, Paris, France; CNRS, UMR 7225, Paris, France. Electronic address: ahmed.idbaih@gmail.com.
Ahmed
A
Idbaih
D000328:Adult; D017668:Age of Onset; D001927:Brain Diseases / Q000453:epidemiology / Q000209:etiology / Q000473:pathology; D002648:Child; D002675:Child, Preschool; D006646:Histiocytosis, Langerhans-Cell / Q000145:classification / Q000150:complications / Q000453:epidemiology / Q000473:pathology; D006801:Humans; D009410:Nerve Degeneration / Q000150:complications / Q000453:epidemiology / Q000473:pathology; D055815:Young Adult