Thyroid blocking antibodies

This hot antibody is linked to radioactive iodine and binds to the CD20 receptor present on B lymphocytes (see Rituximab above). Tositumomab has shown activity in non-Hodgkin s lymphoma. Hematologic toxicity occurs several weeks after administration and may persist for months. Since radioactive iodine may have adverse effects on the thyroid, all patients must receive thyroid-blocking agents. 

Congenital (cretinism) Athyreosis or ectopic thyroid, iodine deficiency TSH receptor-blocking antibodies Absent or present Severe... 

Hypothyroidism, known as myxedema in adults, when severe, is the most common disorder of the thyroid gland. Worldwide, hypothyroidism is most often the result of endemic iodine deficiency. In nonendemic areas, where iodine is sufficient in the diet, chronic autoimmune thyroiditis (Hashimoto s thyroiditis) accounts for the majority of cases. This disorder is primarily characterized by high levels of circulating antibodies against a key enzyme (thyroid peroxidase) in the processing of iodine in the thyroid gland. Blocking antibodies directed at the TSH receptor may also be present. Thyroid destruction may also occur via apoptotic cell death. 

In addition, there is now a keen controversy over the possible role of thyroid-growth-blocking antibodies of maternal origin in the etiology of sporadic congenital hypothyroidism (39-41). 

Studies Acetylcholine receptor binding and blocking antibodies were positive, as was the anti-striated-muscle antibody. Other immunological parameters were normal, as were thyroid function tests. Repetitive nerve stimulation at low-frequency (3 Hz) showed an 18% decremental response of the compound-motor-unit potential indicating MG (normal is < 11 % decrement). Nerve conduction studies were normal. Computed tomography (with contrast) of the mediastinum revealed a mass, presumably thymoma. 

Human chorionic gonadotropin and thus LH, at high concentrations activates the cAMP cascade and consequently proliferation in FRTL-5 cells (Davies and Platzer, 1986 Yoshimura et al., 1990 Yosmmura et al., 1991) and human thyroid cells (Pekonen et al., 1988). As these effects are inhibited by TSH receptor blocking antibodies they are mediated by this receptor (Yoshikawa et al., 1990). The concentrations reached in patients with trophoblastic tumors or even in pregnancy (Pekonen et al., 1988 Yoshimura et al., 1991) are sufficient to activate the human thyroid (Hershman et al., 1988 Kasagi et al., 1989 Yoshikawa et al., 1989). 

Takasu, N., Yamada, T., Takasu, M., Komiya, I., Nagasawa, Y., Asawa, T., Shinoda, T., Aizawa, T., and Kozizumi, Y., Disappearance of thyrotropin-blocking antibodies and spontaneous recovery from hypothyroidism in autoimmune thyroiditis, N. Engl. J. Med. 326 513 (1992). 

Studies Serum IgM anti-GMl antibody titers were elevated. Serum blood counts, general chemistries, vitamin levels, and thyroid and parathyroid tests were normal. CSF protein was 68 mg/dL (normal up to 45 mg/dL). Nerve conductions showed an asymmetric dysschwannian motor polyneuropathy, with "conduction blocks" involving his upper more than... 

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