Pediatric acute appendicitis is one of the most common acute abdominal diseases in pediatric surgery. Because of its rapid onset, atypical history and signs, uncooperative physical examination, and inaccurate medical history provided by the child or his relatives, early diagnosis is difficult, and once the diagnosis is delayed, postoperative complications are more frequent and can be life-threatening in serious cases. The experience of diagnosing pediatric acute appendicitis is summarized, and we hope it can be helpful. The characteristics of pediatric appendicitis: Pediatric appendicitis is rapidly developing compared to adults, with atypical symptoms and signs. It is very common for different physicians or the same physician to examine the child at different times, with widely varying results. Therefore, it is important to repeat the examination and review the abdominal signs regularly, which can make the less certain and less typical signs clear. In general, the younger the pediatric population, the less chance of appendicitis developing, but the greater the chance of appendiceal variation, the difficulty of confirming the diagnosis, and the chance of severe and advanced lesions appearing. Pediatric appendicitis usually starts with a low-grade fever, and later the temperature may rise quickly to 38°C to 39°C as the disease progresses, with persistent hyperthermia if the appendix is perforated with peritonitis. In children with appendicitis and subsequent peritonitis, abdominal muscle tension may not be evident because the abdominal muscles are not well developed. Therefore, care should be taken to prevent two extremes in the abdominal examination. At one extreme, the abdominal muscles are always tense on examination because of the child’s crying and restlessness, and it is easy to mistake total abdominal muscle tension for diffuse peritonitis; at the other extreme, in children with weak abdominal muscles, there is no obvious muscle tension despite the presence of peritonitis, and the determination of the degree of “muscle tension” at this time is particularly important for general practitioners who often deal with The determination of the degree of “muscle tension” is often difficult to grasp, especially for general surgeons who often deal with adults, and can easily be misclassified as “abdominal tenderness”. In the first case, the physician’s sense of the child’s hand between inspirations is particularly important, because in the absence of peritoneal inflammation, the abdomen will suddenly become soft at the moment of inspiration despite the child’s continued crying, whereas in the case of peritoneal inflammation, the abdomen does not relax significantly between inspirations. In the second case, experience is more important and care is taken to remain alert to the peculiarities of abdominal examination in this particular population, but one point may be more practical: muscle tension may not be evident in peritonitis, but a larger range of pressure pain and a distant rebound eliciting an abnormal pain response often suggest the presence of abdominal inflammation. Neonatal appendicitis: Neonatal appendicitis is rare, sometimes we use the term “minimal”. The reason for this is that the process of transforming the appendix from a conical tube to a true canal shape is still ongoing after birth, and the conical lumen is certainly less likely to become obstructed. And when it does occur, it is difficult to show any specific signs other than crying, fever or vomiting, or refusal to eat, which alarm the parents: the child will not indicate that his crying is due to abdominal pain, certainly not the so-called metastatic right lower abdominal pain, and the vomiting combined with fever will make most pediatricians consider it to be related to a gastrointestinal cold or other discomfort. Therefore, when a pediatric surgeon approaches a child, there is often already a perforated appendix or diffuse peritonitis, and the child presents with abdominal distention, diarrhea (rectal irritation sign), or signs of intestinal obstruction. The most important thing at this time is an abdominal examination to determine the presence of signs of peritoneal irritation and, if necessary, a diagnostic laparotomy, abdominal radiograph or ultrasonography. Despite this, a definitive preoperative diagnosis of appendicitis is difficult. As a result, these newborns are often brought to the operating room with significant diffuse membranous inflammation and undergo a dissection. Appendicitis in infants and young children (from a few months to 3-4 years of age before they are able to express themselves clearly) can be detected under careful parental observation by abnormal bouts of crying, or by the phrase “belly pain”, or by a specific position of holding the abdomen in the hand, decreased appetite and occasional vomiting (stomach contents), followed by fever. If this is the case, the first thing the doctor needs to do is to try to keep the child calm and quiet, for example, without the parents releasing him or her and placing him or her alone on a white sheet, or lying flat on the bed with someone closest to the child stroking his or her upper body. For children who often visit the hospital, there is a reflexive fear of the white bed, which requires more patience and cooperation with parents to try various ways to calm them down, such as: let them hug their relatives, turn their backs to the doctor, let their relatives lull them to sleep, or let their relatives first put one hand on the child’s abdomen and say “oh oh oh, Daddy rubs his belly”. Then, after he or she falls asleep or is quiet, quietly switch the doctor’s hand to the child’s abdomen, gently feel the whole abdomen first, then slowly apply light pressure from the lower left abdomen to experience the resistance, and gradually move to the lower right abdomen. Generally, the abdominal pressure pain can be detected from this. However, if the child is extremely uncooperative and crying due to panic and discomfort, the examination becomes more difficult and less reliable. At this time should: 1, continue to make efforts to quiet the child; 2, prolong the abdominal examination time, simply the examiner’s hand fixed in the child’s abdomen, so that its crying and restlessness in a kind of retreat to adapt, after adapting to begin to search, to appreciate the different reactions of the child when each search, if repeatedly in the same area of the search pressure are triggered by the child crying and resistance to the obvious increase, that should be the location of the lesion; 3. If necessary, use a small amount of sedation, to be examined after the child falls asleep, at this time, such as internal diseases, often no pressure pain, and such as deep pressure on a place when the child always appear painful expression, or even crying and wake up, that is, pressure pain, suggesting the location of the lesion; 4, change the time, and then change the time, repeated examination, comparison. However, due to the difficulty and inaccuracy of the above examinations, as well as the difficulty in understanding and grasping them, it may be difficult to get an early diagnosis of appendicitis, even if the child is seen early for some gastrointestinal symptoms. In children of this age, appendicitis is often seen as total peritonitis, right lower abdominal mass or abscess, intestinal obstruction, or referral from pediatrics to pediatric surgery because of the underdevelopment of the appendix and inadequate function of the greater omentum. Given the high incidence of appendicitis, it is also reasonable to speculate conversely that appendicitis may be the first consideration when a pediatric patient in this age group presents with total peritonitis or a painful mass in the right lower abdomen, or intestinal obstruction with signs of infection such as fever and elevated white blood cells. Talking but disobedient children are about 3 to 7 years old, characterized by their ability to express abdominal pain and other discomforts to their parents, but they easily lose patience and refuse to cooperate with the doctor under the interference of disease discomfort and strong stimuli such as repeated examinations and blood draws by the doctor, and sometimes the parents also comply with the child and refuse to repeat the examination by the doctor during observation, etc. In this group of children, it is very important to ask the parents carefully about all the complaints and manifestations of the child before he/she lost patience. Sometimes, attentive parents with general health knowledge can even provide an important medical history of metastatic right lower abdominal pain. With the child, the primary concern remains to try to calm him, with the friendly tone of the doctor or nurse, promises of safety, promises that cooperation will be rewarded, and any temptation to calm or distract him (but please be careful to avoid deception, as this psychological trauma brings future distrust of the doctor as well as the parents that is more difficult to overcome and outweighs the benefits of cooperation in the current examination). In the case of cooperation, the check-up procedure is similar to that of adults. Better still, the doctor’s hand takes one of the child’s hands and teaches him to look into all parts of the abdomen as if he were a student. This not only increases the doctor’s affinity and distracts the child, but more importantly, when there is real pressure pain present, your hand can clearly feel that his hand appears to resist pressure in a certain area, and if he is not throwing a tantrum or happens to have an episode of intestinal spasm at this time, that is the pressure point. If the child is very temperamental and always cries, you can also ask the parents to control his right hand from moving freely and let his left hand go, and the doctor will look for him according to the usual procedure. If there is no pressure pain, the child cries but does not necessarily grab your hand. The factor of certainty is higher when he does not grab your hand when pressing on the left side but comes to grab it when you press on the right lower abdomen. Older children are mainly those who are able to talk and also basically listen, have some restraint and the ability to cooperate with the doctor, usually above the age of 4 to 5 years and up to prepubertal age (around 12 years). The clinical manifestations of appendicitis in these children are close to those of adults, and early diagnosis is relatively easy. However, compared to adults, the progression of the lesion toward suppuration and perforation is still faster due to the anatomical structure, so the propensity to choose surgical treatment after the diagnosis of appendicitis is higher than that of adults. The requirements for examination and abdominal examination of these pediatric patients are generally the same as those of adults. However, special attention should be paid to the fact that they are likely to lie and pretend not to be sick, and their language is often unclear and imprecise, especially with regard to the time of appearance of symptoms and changes in their condition. Therefore, in addition to repeatedly confirming the symptoms and their changes with the children themselves, it is still necessary to ask the parents about some timing issues, as well as the manifestation of symptoms during history taking. In addition to asking questions about pressure and pain, the child’s expression and answers should be taken more seriously. If the child answers that there is no pain when pressure is applied to a certain area but shows protective aspiration, unusual impatience or even painful expressions, it is important to consider whether the child may wish to conceal a physical illness due to fear of injections, hospitalization or surgery. The abdominal examination described above addresses only a portion of palpation and does not fully address all aspects of pediatric appendicitis. For most children with appendicitis, there is no specific change in abdominal appearance or color, abdominal distention is not specific, and there is no specific diagnostic value of active bowel sounds for appendicitis itself. Therefore, the most important (not only important) thing in pediatric appendicitis should be abdominal palpation.