Differential diagnosis (exclusionary diseases) | Acquired hypothyroidism

Differential diagnosis (exclusionary diseases)

An important diagnosis to distinguish from hypothyroidism is low T3/Low T4 syndrome, in which both T3 and T4 are decreased. This syndrome can occur in critically ill patients in intensive care units. In contrast to hypothyroidism, this syndrome does not require hormone substitution with thyroxine.

Therapy

The therapy of hypothyroidism consists of a continuous replacement (=substitution) of the thyroid hormone T4 (L-thyroxine) and regular check-ups by the doctor. In the case of a pronounced hypothyroidism, the hormone dosage should be slowly increased up to the necessary dose, because an overdose of thyroid hormones can lead to cardiac arrhythmia. The optimal dose of hormone administration is determined on the basis of the clinical condition (general condition) of the patient and the value of TSH. The therapy is successful if the patient is free of symptoms and the TSH value is between 0.5-2.0 mU/l.

Complications

Generalized myxedema with water retention in the entire body, including the pericardium (=pericardial effusion), is a serious complication of hypothyroidism and should be treated under intensive medical supervision. It is important to ensure the patient’s breathing and keep the vital parameters (heart rate, blood pressure) stable. The patient receives infusions with glucocorticoids, glucose and salts (=electrolytes).

The thyroid hormone T4 is also replaced by an infusion (=i. v. administration, intravenous administration). If the patient is hypothermic, he should be carefully reheated.