Langerhans cell histiocytosis presenting as eosinophilic granuloma of the bilateral forearms in an 8-year-old girl: a case report

Abstract

BackgroundLangerhans cell histiocytosis previously known as histiocytosis X is a rare disease of children and young adults with a very broad clinical spectrum. In children, its annual incidence is estimated between 0.2–0.5 per 100,000.Case representationAn 8-year-old Moroccan girl with no known personal or family history presented to our institution with painful swelling of both forearms. An X-ray and magnetic resonance imaging were inconclusive. We then performed a biopsy curettage (of her left forearm). Microscopic analysis followed by immunohistochemical analysis disclosed a diagnosis of Langerhans cell histiocytosis. No chemotherapy was necessary. Clinical and radiological improvement was achieved after 6 months.ConclusionThe particularity of this observation is the bilaterality of the lesion on both forearms and it has not previously been reported. Langerhans cell histiocytosis should be included in the differential diagnosis of osteomyelitis and Ewing’s sarcoma.

Unusual sites of bone involvement in Langerhans cell histiocytosis: a systematic review of the literature

“…This finding was consistent with previous study findings [ 3 , 6 , 11 ]. However, unlike studies reporting that LCH disease is more prevalent in children, and rare in adults [ 2 , 4 , 6 , 68 ], our findings showed no difference between the two groups [children = 31 cases (48.44%); adults = 33 cases (51.56%)].…”

“…After reviewing the full text of the 264 articles, 113 articles that lacked eligibility information were excluded. Finally, 60 articles encompassing 64 rare cases met the eligibility criteria to enter the study [ 2 – 4 , 6 – 8 , 14 – 67 ]. Figure 1 shows the flow diagram of the literature search.…”

“…Langerhans cell histiocytosis (LCH) is a rare disease with a prevalence of 2–5 cases per million in children and 1–2 cases per million in adults annually [ 1 , 2 ]. The etiology and pathogenesis of the disease remain unclarified; earlier theories stated that LCH is a reactive process, but recent findings based on the identification of oncogenic BRAF or MAP2K1 mutations in most cases of LCH suggest that it is a clonal neoplasm and originates from the uncontrolled proliferation and accumulation of bone marrow-derived immature myeloid dendritic cells [ 3 – 6 ].…”

“…The etiology and pathogenesis of the disease remain unclarified; earlier theories stated that LCH is a reactive process, but recent findings based on the identification of oncogenic BRAF or MAP2K1 mutations in most cases of LCH suggest that it is a clonal neoplasm and originates from the uncontrolled proliferation and accumulation of bone marrow-derived immature myeloid dendritic cells [ 3 – 6 ]. LCH predominantly affects children ages 5 to 15 years, with a mean age of 3 years [ 2 , 3 ] and is more prevalent in male cases than in female cases [ 2 , 6 ]. Its presentation in neonates and adults is rare [ 7 ] and in those older than 50 years is an exception [ 8 ].…”

“…Recently, based on the revised classification of histiocytoses, LCh has been subclassified as follows: single-system LCH, lung LCH and multisystem LCH with or without risk organ involvement (liver, spleen, and bone marrow) [ 10 ]. The most common form of the disease is single-system LCH of the bone (approximately 75–80%) [ 3 , 10 ], which can manifest as a uni- or multifocal form [ 2 , 6 ]. The unifocal form is more common than the multifocal form.…”