Marine-Lenhart Syndrome

Excerpt

A 47-year-old female with a prolonged history of Graves’ disease with ophthalmopathy as well as a left multinodular retrosternal goiter presents with subclinical hyperthyroidism having a low TSH of 0.006 uIU/ml (0.4–5.0 uIU/ml) with a normal free thyroxine at 1.5 ng/dl (0.7–1.6 ng/dl) and free tri-iodothyronine at 2.5 pg/dl (2.3–4.2 pg/dl). Thyroid-stimulating immunoglobulin was elevated at 456 % (≤122 %). She was previously treated with radioactive iodine therapy 5 years earlier followed by retreatment with 34.1 mCi ¹³¹I 15 months prior to admission due to recurrence of hyperthyroidism. Thyroid scintigraphy prior to her second radioactive iodine treatment was elevated with a 32 % (~5–15 %) 5-hour and 60.7 % (~15–35 %) 23-hour uptake having significant substernal extension with a heterogenous overall uptake (Fig. 1a). Repeat thyroid scintigraphy done (Fig. 1b) as well as a thyroid ultrasound showed a dominant nodule on the midpole of the thyroid measuring 2.7 × 2.3 × 3.1 cm (Fig. 1c). Her 4-hour and 24-hour thyroid uptake were slightly below the normal range at 4.3 and 14.3 %, respectively. There was a redemonstration of multiple photopenic areas involving the left thyroid lobe which may represent focal areas of suppressed activity related to the increased uptake of the substernal left thyroid nodule. The right thyroid lobe was not clearly visualized, which is likely suppressed by the left thyroid nodule (Fig. 1b). The left thyroid nodule was smaller compared with an ultrasound done 14 months earlier. Our patient who had refractory Graves’ disease presented with subclinical hyperthyroidism due to an autonomously functioning thyroid nodule consistent with the diagnosis of Marine-Lenhart syndrome.

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