Thyrotoxic Periodic Paralysis Causing Back Pain and Leg Weakness: An Unusual Presentation of Hyperthyroidism

Table 1

Initial laboratory investigations.

Lab	Value	Reference	Units
Potassium	1.7	3.5–5.0	mmol/L
Magnesium	1.3	1.5–2.2	mEq/L
Phosphorus	1.5	2.6–4.9	mg/dL
TSH	0.010	0.450–5.330	mIU/ml
Free T4	2.98	0.58–1.64	ng/mL
Total T3	399	76–181	ng/dL
TSI	278	<140	% of baseline
Thyroglobulin antibodies	20.0	≤1	IU/mL
Thyroid peroxidase antibodies	180.0	<9	IU/mL