A 40-year-old housewife was referred to our hospital for evaluation of a thyrotoxic state. A month after rubella infection, she developed heat intolerance. Physical examination revealed a hard and non-tender goiter with no signs or symptoms of inflammation. Free thyroid hormones were high and TSH was undetectable. 123I-thyroidal uptake was suppressed. Antithyroglobulin and anti-microsomal antibodies were negative throughout the course. A serologic study revealed high levels of anti-rubella antibodies. After a month without any treatment, she became euthyroid. Free thyroid hormones and TSH gradually became normal and the antibodies to rubella decreased. 123I-thyroidal uptake increased. From the clinical course, the patient was diagnosed as having silent thyroiditis. We suggest that viral infection such as rubella could cause the development of silent thyroiditis.

Plasma renin activity (PRA) and inactive renin(IR, activated by trypsin) were measured in the plasma of 15 type II diabetics with autonomic neuropathy (group 3), 15 type II diabetics without (group 2), and 14 nondiabetic control subjects (group 1) in the recumbent position. There were no significant differences between the 3 groups with respect to age, ideal body weight, supine resting mean blood pressure, serum creatinine, daily urinary excretion of sodium, or renin substrate at the time of study. Autonomic neuropathy (AN) was assessed by measurement of the ratio of the longest to the shortest R-R interval during deep breathing (E/I-ratio) and by postural hypotension. PRA was significantly lower in group 3 than in group 1 (p less than 0.05). The IR level was significantly higher in group 3 than in groups 2 and 1 (p less than 0.005 for both comparisons). The ratio of active renin to total renin (TR) (PRA/(IR + PRA)) was significantly lower in group 3 than in groups 2 and 1 (p less than 0.001 for both comparisons). The IR level and PRA/(IR + PRA) were significantly correlated with E/I-ratio (r = -0.498, p less than 0.01 and r = 0.588, p less than 0.001, respectively) and with the severity of postural hypotension (r = 0.383, p less than 0.05 and r = 0.401, p less than 0.05, respectively), but not with the daily urinary excretion of protein or 24 h-creatinine clearance (24 h-Ccr) in the whole diabetics. From these results, we conclude that autonomic neuropathy might be a more important factor than nephropathy in the lower PRA and higher IR level in type II diabetics with AN.

A variety of abnormality has been reported in the cation transport systems in erythrocytes in essential hypertension. To determine the existence of similar abnormality in diabetics with hypertension, sodium (Na+) influx into erythrocytes in the presence of ouabain (measured by using 22Na+), and the Na+ and potassium (K+) content in intact erythrocytes were examined. Subjects, all of whom were Japanese, were divided into 4 groups; 23 nondiabetic, normotensive control subjects without family history of hypertension (control group), 20 patients with essential hypertension (group 1), 21 normotensive diabetics without family history of hypertension (group 2) and 15 hypertensive diabetics (group 3). Na+-K+ pump activity (measured by using 86Rb+) was studied in some of them, too. Na+ influx in group 1 was 0.451 +/- 0.111 m mol/Kg erythrocytes/h, significantly more elevated than that in the control group (0.345 +/- 0.080, p less than 0.001). Na+ influx in group 2 (0.435 +/- 0.094) was significantly greater than that in the control group (p less than 0.005), but no significant difference was found between groups 1 and 2. Na+ influx in group 3 (0.551 +/- 0.128) was significantly higher than that in the control group (p less than 0.001), in group 1 (p less than 0.02), or in group 2 (p less than 0.005). There were no significant differences in Na+-K+ pump activity, or Na+ and K+ content among the 4 groups. These findings suggested that: Na+ influx into ouabain-treated erythrocytes was higher in patients with essential hypertension than in control subjects in Japanese, diabetes mellitus per se might increase Na+ influx, and the elevation of blood pressure in hypertensive diabetics as well as in essential hypertensives might be related to the increased Na+ influx.

No abstract

An 11-year-old-girl with silent thyroiditis associated with a transient increase in serum IgM and thyroid hormone is described. The levels of serum IgM decreased from 4.38 g/L to 3.35 g/L after 1.5 months at the same time as thyroid hormones returned to normal. An unidentified antecedent infection or exposure to antigen causing the increase in serum IgM might have triggered the occurrence of silent thyroiditis in this patient, although a search for viral antibodies revealed no significant titer changes during the course of the disease.