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Childhood immunologic disorder characterized by
pathologic proliferation of histiocytes caused by the Langerhans cells.
Involves mainly the skin, bones, brain, lungs, spleen, and liver. The presence
of diabetes insipidus must be considered. Presents
nonmalignant growths that represent accumulation of histiocytes. Poor
prognosis (70% mortality).
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Letterer-Siwe Syndrome; Abt-Letterer-Siwe Syndrome; Siwe Disease.
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Reported between 1:200,000 and 1:3,300,000 live births.
Most cases are sporadic.
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Evidence supporting both autosomal dominant
and recessive inheritance in different families.
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Letterer-Siwe
disease (LSD) is one of the
Langerhans cell histiocytoses (LCH). Physiologically, Langerhans cells
detect non-self-antigens and present them to the cells of the immune system
(T cells), thus allowing an appropriate immune response from the body. They
are normally found in the epidermis of the skin, but in LSD they spread to
bone and other tissues and become associated with eosinophils. Lesions arise
in many organs, including bone, skin, spleen, liver, lungs, lymph nodes, and
brain. Granulomatous inflammatory lesions develop and may proliferate and
become destructive. These lesions later become less cellular, necrotic, and
fibrotic.
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The hallmark of LSD is the presence of pathologic
Langerhans cells in involved tissues. Specific histochemical, immunologic,
and protein markers have been identified (Birbeck granules or positive S-100
beta protein and CD Ia antigen). These biochemical findings in addition to
multiorgan involvement help make the diagnosis.
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Although LSD has been described in adult
patients, it is predominantly a condition affecting children age 2 months to
3 years. Clinical features include fever, anemia, thrombocytopenia, and the
manifestations of histiocyte proliferation, including skin disorders
(seborrheic, eczematous, pustular or nodular lesions particularly on the
scalp), lytic lesions of the bones, and splenogenic thrombocytopenia. The
lungs can be involved (nonproductive cough, dyspnea, pleural effusion,
interstitial pneumonitis, and spontaneous pneumothorax). Hypothalamic
involvement resulting in diabetes insipidus (DI). Eye protrusion may be
present. The clinical course is very variable, and spontaneous remissions
have occurred. Prognosis is generally poor. Treatment may include use of
glucocorticoids, chemotherapeutic agents, bone marrow transplantation, and
desmopressin for DI.
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Blood examination: cell blood count, platelet
count must be
obtained. Determine whether DI is present; evaluate electrolytes. Evidence of long
bone involvement should be sought. Consider perioperative glucocorticoid
coverage. A chest x-ray film should be obtained. Coagulation profile and bleeding
time must be available.
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Correction of anemia and
thrombocytopenia may be necessary. Be vigilant for presence of DI. Care
should be taken when moving patients to prevent pathologic fractures where
bony lesions are present. In the presence of lung involvement, the
potential for pneumothorax, and/or pleural fusion, mechanical ventilation
must be used judiciously.
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Perioperative glucocorticoid coverage
may be necessary. Consider side effects of chemotherapeutic agents.
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Histiocytosis: Rare spectrum of disorders characterized by
proliferation and accumulation of histiocyte in various lesions within the
body. Lesions may include Langerhans cells, monocytes, and eosinophils. Most
affected individuals have single or multiple bone ...