What is a severe form of adult hypothyroidism caused by a deficiency of T₃ and T₄ characterized by facial puffiness?

The severe form of adult hypothyroidism caused by a deficiency of T₃ (Triiodothyronine) and T₄ (Thyroxine) and characterized by facial puffiness is known as Myxedema.

Here are the steps to understand this:

1. Hypothyroidism is a condition where the thyroid gland doesn't produce enough thyroid hormones.

2. The thyroid hormones include T₃ (Triiodothyronine) and T₄ (Thyroxine). These hormones are crucial for the body's metabolism and energy production.

3. When there is a severe deficiency of these hormones, it can lead to a condition called Myxedema.

4. Myxedema is a severe form of hypothyroidism that is characterized by swelling of the skin and underlying tissues, giving a waxy consistency. Facial puffiness is one of the common symptoms of this condition.

5. Other symptoms of Myxedema can include fatigue, weight gain, cold intolerance, joint and muscle pain, constipation, dry skin, thinning hair, decreased sweating, heavy or irregular menstrual periods, and fertility issues.

6. Myxedema is a serious condition that requires immediate medical attention as it can lead to life-threatening complications if left untreated.