Browsing by Author "Sharma, Om P. (7202888436)"

PURPOSE OF REVIEW: We will review the role of the eosinophil as an innate immune cell. There have been recent advances in the regulatory mechanisms of the eosinophil, in terms of priming and migration. Additionally, we will discuss certain pulmonary diseases that are associated with eosinophilia. RECENT FINDINGS: Rapid binding of immunoglobulin A-coated beads can prime the eosinophil cell in the trafficking process. Tissue factor has been shown to be expressed within eosinophil granules. It is believed to serve as a critical eosinophil mediator within the peripheral bloodstream. Interleukin-8 serves as a chemoattractant through IL8RA and IL8RB receptors, but patients with an IL8RA-B ht2 have peripheral eosinophilia. Interleukin-10 and eotaxin correlate with eosinophilia and an active infection prior to therapy. After therapy, interleukin-5 and 6 correlated appropriately with eosinophilia. A wide differential diagnosis exists for peripheral eosinophilia. One study has shown that 86 out of 103 patients with unknown causes for peripheral eosinophilia had positive toxocara enzyme-linked immunosorbent assay results. SUMMARY: The effect of the cytotoxic eosinophil cell is not only harmful to foreign invaders within the body, but through an intricate immunological pathway, eosinophils can become detrimental to the host organs. © 2007 Lippincott Williams & Wilkins, Inc.

In sarcoidosis, the thyroid and the kidneys are infrequently affected. Clinically recognizable thyroid involvement occurs in < 1% of sarcoidosis patients. Hyperthyroidism, myxodema, and thyroid occur with an equal frequency. It is important to distinguish sarcoidosis of the thyroid from other infections and disorders of the gland. Renal involvement may present as granulomatous infiltration of the renal parenchyma, glomerulonephritis, renal arteritis, and nephrocalcinosis or renal stones. The latter are due to abnormalities of calcium metabolism. Hypercalcemia occurs in about 10 to 13% of sarcoidosis patients; hypercalciuria is three times more frequent. Calcium abnormalities may precede, follow, or occur at any time during the course of sarcoidosis. An endogenous overproduction of 1,25-dihydroxyvitamin D [1,25-(OH 2 )-D 3 ] by granulomatous tissue and activated macrophages results in an increase of intestinal absorption of calcium. Corticosteriods, chloroquine, and hydroxychloroquine subdue 1,25-(OH 2 )-D 3 production and correct hypercalcemia and hypercalciuria.

A granuloma is a focal collection of inflammatory cells that include mononuclear cells, macrophages, and giant cells along with a number of lymphocytes, plasma cells, and fibroblasts. Granulomatous reactions may be classified functionally into two major categories (1). The first group consists of lesions characterized by delayed-type hypersensitivity, antigen- specific response. These granulomas have a high rate of cell turnover, are very active lesions, and are seen in tuberculosis, sarcoidosis, hypersensitivity pneumonitis, and schistosomiasis. The second type is a foreign body granuloma that lacks an antigen-specific response and often is an inactive, minimally destructive lesion. These low-turnover granulomas are seen in berylliosis, where the offending agent is inanimate and inert. The composition of the causative irritant and its degradability and immunogenecity are decisive factors in the development of a granuloma (2). © 2006 by Taylor and Francis Group, LLC.