Witch two illnesses feature cramps as one of the symptoms?

Heat stroke is the most severe form of hyperthermia.

Some illnesses that feature cramps as a symptom:

Peripheral Neuropathy  (Nerves malfunctioning due to damage)

Rickets  (Lack of Vitamin D)

Hypokalemia  (low potassium levels in the blood)

Kidney Failure  ( when your kidney stops regulating toxins in your body)

Amyotrophic Lateral Sclerosis (ALS) (degenerative disease that affects the brain and spinal cord. It causes loss of control of voluntary muscles)

Celiac Disease )a digestive disorder caused by an abnormal immune reaction to gluten.