LANGERHANS CELL
HISTIOCYTOSIS INVOLVING THYROID GLAND
G. Kale, Z. Akcoren, M. Caglar, N. Yordam, S.
Muftuoglu,
ME. Senocak, N. Kandemir, F. Kaymaz.
Hacettepe University Ihsan Dogramaci Children’s
Hospital,
Ankara, Turkey
Involvement of the thyroid gland by Langerhans cell
histiocytosis (LCH) is rare. A small number of cases have been described,
and most of them were previously known as having LCH. A 16-year-old girl
had been followed up since the age of 12, with a diagnosis of diabetes
insipidus (DI) for which no specific aetiology could be shown. One year
prior to her last admission, a multinodular goitre was detected with normal
thyroid function tests. Antimicrosomal and antithyroglobulin antibodies
were found to be increased. Physical examination on her last admission
revealed a multinodular, firm thyroid gland, and the patient underwent a
subtotal thyroidectomy with the initial diagnosis of Hashimoto thyroiditis.
Microscopic examination revealed marked disruption of the thyroid by an
infiltrate consisting of clusters and sheets of histiocytes, prominent
eosinophils, and a small number of lymphocytes separated by a dense
fibrovascular stroma. Small foci of necrosis were seen within the
infiltrate and fibrous tissue. Histiocytes showed pale eosinophilic
cytoplasm and oval vesicular nuclei, and stained positively with S-100
protein. Electron microscopy revealed characteristic Birbeck granules
within the cytoplasm of these cells. Thyroid antibodies were found to be
increased, but histologically only fibrosis and a mild lymphocytic
infiltration were detected in our patient, and these findings do not
suggest Hashimoto thyroiditis. Although DI is the most frequently
encountered endocrinologic abnormality in LCH, involvement of the thyroid
gland, though quite uncommon, may also occur in this disease and may lead
to goitre.