Primary intussusception is most common in infants and young children within two years of age, and is most common between 6 and 12 months of age. It is characterized by sudden onset, with paroxysmal crying abdominal pain, vomiting, bloody stools, and abdominal masses as typical manifestations.
First, since infants under one year of age do not complain of abdominal pain, they mostly present with sudden onset of paroxysmal crying, leg flexion, pallor, and refusal to eat, and each attack can last from several minutes to tens of minutes. More attention should be paid.
Secondly, when repeated episodes of abdominal pain, vomiting soon appears, initially as milk lumps or food residues, and later with bile-like yellow liquid, and in the late stage can vomit fecal-like liquid.
Thirdly, there may be one or two normal stools at the beginning of the illness, and about eight to twelve hours later there may be dark red blood stool or a mixture of blood and mucus, so it is called jam-like stool.
Fourth, there is a swelling in the abdomen, the size of which varies depending on the location of the intussusception and the degree of entrapment. Most of them occur in the area of ascending colon, transverse colon or descending colon. In the early stage of the disease, the abdomen is soft and soft, and the sausage-like mass can be palpated under the right upper abdomen or umbilicus, while the right lower abdomen is soft and has a feeling of emptiness.