Use of soy protein supplement and resultant need for increased dose of levothyroxine.

OBJECTIVE: To report a case of difficulty in achieving suppressive serum levels of thyroid hormone because of malabsorption of exogenous levothyroxine attributable to daily ingestion in close temporal relationship to the intake of a soy protein-containing food supplement. METHODS: We present the relevant history and laboratory data of the current case and provide supportive documentation from the literature. RESULTS: A 45-year-old woman who had hypothyroidism after a near-total thyroidectomy and radioactive iodine ablative therapy for papillary carcinoma of the thyroid required unusually high oral doses of levothyroxine to achieve suppressive serum levels of free thyroxine (T(4)) and thyrotropin (thyroid-stimulating hormone or TSH). She had routinely been taking a "soy cocktail" protein supplement immediately after her levothyroxine. Temporal separation of the intake of the soy protein cocktail from the administration of the levothyroxine resulted in attainment of suppressive serum levels of free T(4) and TSH with use of lower doses of levothyroxine. CONCLUSION: Administration of levothyroxine concurrently with a soy protein dietary supplement results in decreased absorption of levothyroxine and the need for higher oral doses of levothyroxine to attain therapeutic serum thyroid hormone levels.

Drugs for cardiovascular risk reduction in the diabetic patient.

The diabetic patient is at increased risk for cardiac events. Lowering hemoglobin A1c levels even within the normal range is associated with less cardiac risk. Oral agents for diabetes that reduce insulin resistance and its associated cardiac risk factors in addition to lowering glucose should be used. Energetic reduction of blood pressure with an emphasis on the use of angiotensin-converting enzyme inhibitors and beta blockers will further reduce cardiac risk. Reduction of low-density lipoprotein and triglyceride levels and elevation of high-density lipoprotein levels through judicious use of statins and other anti-lipid agents is essential and will lower the rate of cardiac events in the diabetic patients even more than in the nondiabetic patients. In addition, aspirin and folic acid supplementation should be utilized. Use of a multiple risk factor management strategy with these drugs will lower morbidity and mortality, improve quality of life, and save cost for the diabetic patient.

Chronic fatigue syndrome update. Findings now point to CNS involvement.

Neither Epstein-Barr virus nor human herpesvirus 6 appears to play a causative role in chronic fatigue syndrome. The possibility that a novel human retrovirus may be present in patients with the syndrome needs further study. A number of abnormalities found in patients with chronic fatigue syndrome point to central nervous system (CNS) involvement. These include immunologic abnormalities, indications of pituitary and hypothalamic involvement, abnormal basal plasma levels of certain neurotransmitter metabolites, and cerebral perfusion abnormalities. The symptom pattern of chronic fatigue syndrome may eventually be explainable in terms of CNS dysfunction.