The involuntary twisting of the body of an eight-month-old child may be related to hypocalcemia, phenylketonuria or purulent meningitis. 1. Hypocalcemia: hypocalcemia can be caused by insufficient perinatal vitamin D of the mother, insufficient sunlight or fast growth rate, etc. The child may have twitching of the limbs and involuntary twisting of the body. 2. Phenylketonuria: it is an autosomal recessive genetic disease, and the clinical manifestations of the children are backward intellectual development, light pigmentation of the skin and hair, and foul smell of rat urine, and there may be small seizures, and a few of them have increased muscle tone. 3. Purulent meningitis: Streptococcus pneumoniae, meningococcus and other pathogens can invade the meninges through the bloodstream, adjacent tissue infection and other pathways, clinically acute fever, convulsions, impaired consciousness, and meningeal irritation signs and other manifestations. The children’s body involuntarily twisting in August is recommended to go to the regular hospital specialist in time to improve the electroencephalogram, imaging and other related examinations, to clarify the cause of the disease, and then to the cause of the symptomatic treatment.