Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: UMLS:C0019621 (Langerhans cell histiocytosis)
 3,250 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

A histochemical study of enzymatic activities was undertaken in five cases of histiocytosis X (two localized bone forms, two generalized forms, and one involving mainly the skin), each of which revealed characteristic structural features at the optical and ultrastructural levels. A confirmation was made of the original assumption of high acid alpha-D-mannosidase activity, i.e. activity described in human Langerhans intraepidermal cells (Elleder, 1975). In the control group of tumors, with the exception of urticaria pigmentosa, enzyme activity was either at trace level or altogether absent. Acid alpha-D-mannosidase activity therefore appears to be the first biochemical feature common to both histiocytosis X and the Langerhans cells. The significance of the finding for the present theory of the histogenesis of the above tumors is discussed.
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PMID:alpha-D-mannosidase activity in histiocytosis X. 41 26

An 11-year old Caucasian female with a remote history of urticaria pigmentosa presented with a neck mass. A biopsy demonstrated a large intradermal nodule composed of unusually large epithelioid mast cells, including a prominent subset with bi-lobed and multi-lobed nuclei. By immunohistochemistry, the cells expressed CD117 (C-Kit), mast cell tryptase, CD68, and CD25, and were negative for CD163, CD1a, and S-100, confirming the diagnosis of mastocytoma. Equally prominent was an admixed infiltrate of CD68 and CD163-positive xanthomatous histiocytes that included Touton-type giant cells. Eosinophils were abundant. At 7 months follow-up, there was no recurrence of the lesion following complete excision. However, given the unusual cytologic features, close clinical observation is warranted, as the long-term biologic potential of mastocytoma with this degree of cytologic atypia is uncertain. Awareness of this unusual morphologic variant is also important as the histologic features may mimic such childhood neoplasms as juvenile xanthogranuloma and Langerhans cell histiocytosis.
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PMID:Histiocyte-rich pleomorphic mastocytoma: an uncommon variant mimicking juvenile xanthogranuloma and Langerhans cell histiocytosis. 1960 70

Juvenile xanthogranuloma (JXG) is one of the most common forms of non-Langerhans cell histiocytosis in children. Although it usually presents as a self-limited skin lesion with typical histopathology, JXG can be challenging to diagnose due to an atypical initial presentation with corresponding variable histopathology for different stages of development. We present challenging cases of JXG from Sydney Children's Hospital, collected over 10 years - two with multisystem involvement and concomitant urticaria, one associated with neurofibromatosis, and one case of giant JXG with an initial histopathological challenge. Although JXG has been reported with urticaria pigmentosa, in two of our cases persistent urticaria, in association with JXG is discussed.
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PMID:Juvenile xanthogranuloma: challenges in complicated cases. 2207 Jul 4

Scabies is a common parasitic human infection in infants and children. However, diagnostic pitfalls are frequent in infants, in whom the clinical presentation is usually atypical and different from that in adults. In nodular scabies, lesions may be clinically or histologically misdiagnosed as Langerhans cell histiocytosis, insect bite reaction, non-Langerhans cell histiocytosis, lymphoma, or urticaria pigmentosa. We report two misleading cases of young infants (10- and 12-month-old infants) who presented with pruritic brown-red lesions on their trunks and showing a positive Darier's sign, suggestive of urticaria pigmentosa.
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PMID:Scabies mimicking mastocytosis in two infants. 2438 36

Scabies, a mite infestation caused by 'Sarcoptes scabiei', most commonly presents as pruritic linear burrows where the mite has invaded the skin. Scabies variant such as bullous, crusted, hidden, incognito, nodular and scalp-mimic the other conditions. In addition, atypical presentations of scabies can masquerade as dermatitis herpetiformis, ecchymosis, Langerhans cell histiocytosis, systemic lupus erythematosus, urticaria, and urticaria pigmentosa. A 59-year-old male presented with non-pruritic papulosquamous plaques on his chest, abdomen, and back resembling lesions of pityriasis rosea in morphology and distribution. The complete cutaneous examination also demonstrated burrows on his finger webs. A mineral oil preparation of skin scrapings showed scabies mites, ova, and scybala. His infestation resolved after the treatment with topical permethrin 5% cream and oral ivermectin 15 mg on days one and eight. In conclusion, scabies surrepticius is a term that has recently been established to unify not only the numerous variants but also the atypical presentations of scabies. The inaccurate diagnosis of scabies infestation can lead to increased medical costs and the side effects of unnecessary tests and the treatment. Pityriasis rosea-like scabies can be added to the list of atypical presentations that are included under the unifying designation scabies surrepticius.
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PMID:Scabies Surrepticius: Scabies Masquerading as Pityriasis Rosea. 2949 50