A Case of Thyrotoxicosis During Lithium Therapy / 대한내분비학회지

Lithium has been established as a drug useful for the treatment of manic depressive disorder. It is now well recognized that long-term administration of this drug is associated with various antithyroid effects such as goiter, and subclinical and overt hypothyroidism. However, it has been associated less commonly with thyrotoxicosis. Recently we experienced a case of thyroitoxicosis during lithium therapy. A 24-year-old man treated with lithium carbonate 900 mg-1,200 mg/day for manic-depressive illness for four weeks. He then complained of nervousness, palpitation, tremor, heat intolerance, and sweating. Neck pain was not noted. At that time the results of thyroid function test were consistent with hyperthyroidism: T3 568.8 ng/dL, TSH 0.01 mU/mL, FT4 6.0 ng/dL, but 24 hr radioiodine uptake was 0.3%. We suspected this case as lithium induced thyrotoxicosis and discontinued lithium administration. After discontinuation of lithium thyrotoxic symptoms were subsided. One month later, thyroid hormon levels became normalized: T 100.2 ng/dL, TSH 0.06 mU/mL, FT4 0.97 ng/dL and 24hr radioiodine uptake was 16%. We report this case with review of literatures.

The Effects of Handgrip and Cold Pressor Test on Mitral Flow in Patients with Left Ventricular Hypertrophy

BACKGROUND: Handgrip and cold pressor test may increase the afterload of the heart. And in left ventricular hypertrophy, it is known that mitral flow pattern is affected by decreased left ventricular compliance. We investigated the effects of handgrip and cold pressor test on mitral flow pattern in patients with left ventricular hypertrophy. METHODS: Handgrip and cold pressor test were performed in 12 subjects with left ventricular hypertrophy and in 14 healthy normal subjects. In supine position, blood pressure, heart rate and Doppler echocardiographic parameters(early peak flow velocity : E, atrial peak flow velocity : A) were obtained at rest, 1 and 3 minutes after the onset of tests respectively. RESULTS: In both groups, handgrip and cold pressor test increased blood pressure slightly without a statistical significance. In left ventricular hypertrophy group, there were significant increments in heart rates at 1 minute of handgrip (78+/-12min-1, p<0.001) and cold pressor test(77+/-7min-1, p<0.05) as compared to that at rest (73+/-12min-1). Mitral flow velocities did not show significant change after the tests in control group. A waves after 1 minute of handgrip(85.2+/-18.4cm/sec, p<0.05) and cold pressor test (87.3+/-17.8cm/sec, p<0.001) showed significant increases as compared to that at rest (79.1+/-14.9cm/sec) in left ventricular hypertrophy group whereas E waves did not. CONCLUSION: Although handgrip and cold pressor tests did not affect the mitral flow significantly in control group, each test raised A waves in left ventricular hypertrophy group. These results suggest that increased A waves may be due to a rise in afterload and decreased left ventricular compliance caused by handgrip and cold pressor test in left ventricular hypertrophy group.