Insulin resistance in nodular thyroid disease.

BACKGROUND: Insulin had been shown to have a mitogenic effect on thyroid cell cultures. The aim of this study was to investigate insulin resistance in patients with euthyroid nodular goiter. METHODS: Sixty-three patients with nodular thyroid disease and 83 healthy controls were included in the study. Both the patient and the control group were euthyroid, euglycemic and normotensive. None of the study subjects had risk factors for insulin resistance. All the study subjects were evaluated by serum insulin levels and biochemical parameters and thyroid ultrasound. All subjects with thyroid nodules greater than 1cm (n = 36) were offered to undergo thyroid fine needle aspiration biopsy. RESULTS: The two groups were similar with respect to age, gender, BMI, waist circumference, serum lipid levels, serum fT3, fT4 and TSH levels. But HOMA was found to be significantly higher in the patient group (p: 0.007) and thyroid volume was significantly greater in the patient group (p = 0.03). In the patient group there was a significant correlation between HOMA and nodule volume (p < 0.001) while there was not a significant correlation between HOMA and number of thyroid nodules. Thyroid cancer was diagnosed in 3 of the 36 patients (8.33 %). CONCLUSIONS: Insulin resistance may induce increased thyroid proliferation and nodule volume and nodule formation. Therefore, insulin resistance may be a risk factor for euthyoid nodular goiter.

Mean platelet volume in patients with subclinical hypothyroidism.

Subclinical hypothyroidism (SCH) is frequently encountered in the general population. Since it is generally asymptomatic, these patients are mostly identified through routine screening or evaluation of non-specific symptoms. It has been suggested as a risk factor for cardiovascular disease. On the other hand, mean platelet volume (MPV), which is a determinant of platelet function, is an independent risk factor for cardiovascular disease. The aim of this study was to evaluate MPV values in subclinical hypothyroidic patients when they were subclinical hypothyroidic and became euthyroidic after 12 weeks of levothyroxine replacement therapy. Sixty patients with subclinical hypothyroidism and 78 euthyroid healthy subjects matched for age, gender and body mass index were enrolled in the study. None of the study subject had diabetes, hypertension or dyslipidemia. All the study subjects were evaluated by biochemical and platelet parameters. Subclinical hypothyroidic patients were then reevaluated with the same parameters when they became euthyroid after 12 weeks of levothyroxine treatment. Platelet counts and metabolic parameters, except serum triglyceride and high density lipoprotein cholesterol (HDLC) levels, were similar between the two groups. Serum triglyceride and MPV values were significantly higher (pTG=0.007 and pMPV<0.001) while HDLC levels were lower (pHDLC=0.008) in the subclinical hypothyroidic group. MPV was found to be correlated with only antithyroid peroxidase (anti-TPO) antibody levels (P<0.001). MPV values were decreased after subclinical hypothyroidic patients became eythyroid. However, post-treatment MPV values were still higher (p=0.035) in the patient group than in control group. These results suggest that subjects with SCH are susceptible to increased platelet activation and increased MPV values which contribute to increased risk of cardiovascular complications.

Erythema multiforme associated with gemfibrozil monotherapy.

BACKGROUND: A case of erythema multiforme associated with gemfibrozil monotherapy. METHODS AND RESULTS: A 46-year-old man with hyperlipidemia was treated with 600 mg gemfibrozil twice a day. On the fifth day of treatment, skin lesions consistent with erythema multiforme appeared. With the discontinuation of the treatment and start of a topical steroid treatment, the lesions recovered after 4 weeks. After 6 months, when gemfibrozil therapy was restarted, lesions reappeared on the fourth day of therapy. Lesions recovered again following the previous treatment strategies after 4 weeks. An objective casualty assessment suggests that erythema multiforme was probably related to gemfibrozil monotherapy. CONCLUSION: Patients starting gemfibrozil therapy should be warned about the occurrence of erythema multiforme in addition to previous reported and established side effects.

Clomiphene citrate-induced severe hypertriglyceridemia.

OBJECTIVE: To report a case of severe hypertriglyceridemia associated with clomiphene citrate (CC) treatment. DESIGN: Case report. SETTING: A patient referred to an endocrinology clinic of a state hospital. PATIENT(S): A 29-year-old, overweight woman with a history of polycystic ovary syndrome who had been given clomiphene citrate (CC) for ovulation induction and presented with severe hypertriglyceridemia. She had a family history of type 2 diabetes and hyperlipidemia. INTERVENTION(S): Clomiphene citrate treatment was discontinued, and gemfibrozil treatment at a dose of 1,200 mg/d was started. MAIN OUTCOME MEASURE(S): Serum lipid levels. RESULT(S): With the discontinuation of CC treatment and start of a specific lipid-lowering agent, the patient's lipid profile improved. After 3 months, CC therapy was restarted, and again severe hypertriglyceridemia developed, which resolved with the previous treatment strategies. CONCLUSION(S): Clomiphene citrate should be used cautiously in women having risk factors for dyslipidemia, and, even in the presence of a normal lipid profile, lipid levels should be closely monitored when CC treatment is instituted.