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J A Winkelstein

Publications and source records attributed to J A Winkelstein.

154 records · Page 9Linked to original sources

The role of complement in the host's defense against Streptococcus pneumoniae.

In recent years there has been a growing realization that the complement systems plays an important role in the host's defense against infection and that it plays an especially critical role in both natural and acquired immunity to Streptococcus pneumoniae. The terminal components of the complement system, C3-C9, are responsible for most protective functions of the complement system. However, in order to subserve their protective functions, C3-C9 must first be activated. In vitro studies have shown that pneumococci are able to activate the terminal components of complement, C3-C9, by at least two different mechanisms, the classical and alternative pathways. Regardless of the pathway of their activation, C3-C9 produce anaphylatoxic, chemotactic, and opsonic activities in serum, each of which has the potential to play an important protective role in pneumococcal infections. Studies with experimental animals and the experience gained from study of complement deficiencies in humans have each fulfilled the promise of the in vitro studies by demonstrating that the complement system plays a biologically significant role in vivo in the host's defense against S. pneumoniae.

Animals↗

Lymphoid malignancy as a presenting sign of ataxia-telangiectasia.

Ataxia-telangiectasia (AT) is an uncommon genetic disorder characterized by cerebellar ataxia, oculocutaneous telangiectasias, progressive immunodeficiency, and a predisposition to lymphoid malignancy. The genetic defect in AT predisposes not only to malignancy but also to severe toxicity from anti-neoplastic therapies. It is important to consider the diagnosis of AT in any child with a lymphoid malignancy at a younger than expected age, or who has a pre-existing ataxia, to anticipate unusually severe toxicities from the antineoplastic therapy, to avoid confusing the development of ataxia with toxicity from therapy, and to provide appropriate genetic counseling. We describe two children at a young age with a lymphoid malignancy diagnosed before the diagnosis of AT. One patient had severe toxicity from his chemotherapy, requiring truncation of the planned course of treatment. The other child was able to tolerate his entire planned course of therapy, but ataxia that was initially interpreted as toxicity from chemotherapy rather than as a sign of his AT developed. Lymphoid malignancy may be the presenting sign of AT. Making this diagnosis may influence therapy of the malignancy. The neurologic manifestations of the disease can be misinterpreted as toxicities of the chemotherapy, and diagnosis of AT allows appropriate genetic counseling for the family.

Ataxia Telangiectasia↗