Acute appendicitis is the most common disease in pediatric abdominal surgery. The age of onset is 6 to 12 years old, accounting for 90% of cases; it is rare under 3 years old and rare in newborns. The incidence is slightly higher in boys than in girls. In recent years, due to the progress of medical technology, the mortality rate of pediatric acute appendicitis has decreased significantly, mostly to less than 0.1% at home and abroad. However, infants and young children have difficulty in diagnosis, high perforation rate and many postoperative complications, and the mortality rate is about 2% as reported in the domestic literature.
A. Characteristics of pediatric appendicitis
1, low incidence The incidence of pediatric appendicitis is lower than that of adults, and the incidence of infants is even lower. Because of the large opening of the appendix in infants and children, the appendix is funnel-shaped, and the appendix cavity should not be obstructed; in addition, infants eat milk, food residue less, etc..
2, easy to perforate Poor systemic defense function and low resistance in children. Appendiceal wall is thin, such as inflammation is easy to perforate.
3, easy to complicate peritonitis Pediatric omentum is not fully developed, shorter and thinner, perforation of the inflammation should not be limited, often resulting in diffuse peritonitis.
4, systemic symptoms heavy infants and children after the onset of systemic toxic symptoms. The perforation rate is high, and there are many postoperative complications.
The appendix is relatively high, free and mobile, and the appendiceal tract is relatively long, so the site of pressure pain may not always be at the McDonald’s point.
6.High misdiagnosis rate The younger the child is, the more inaccurate the medical history is, the symptoms are not typical, and the examination is not cooperative, so it is also misdiagnosed.
The incidence of ectopic appendicitis in children is high, and parasitic appendicitis is also more common than in adults.
Clinical manifestations
The main symptoms of acute appendicitis are similar to those of adults, but due to the different age and clinical pathology of each type of appendicitis in children, there are differences in their symptoms, signs and physical examination methods.
(A) Appendicitis in children
1.Symptoms
(1) Abdominal pain
The typical abdominal pain is periumbilical or epigastric pain, which shifts to the right lower abdominal pain after a few hours, that is, metastatic abdominal pain. The nature of abdominal pain is mostly persistent dull pain, which may be accompanied by paroxysmal intensification. Children with appendicular cavity obstruction may have severe paroxysmal colic. In a small number of children, the abdominal pain is initially located in the right lower abdomen. The formation of diffuse peritonitis after perforation may lead to total abdominal pain.
(2) Gastrointestinal symptoms
There is vomiting within a few hours after the onset of abdominal pain, usually not many times, and the vomiting is the stomach contents. Late vomiting is most often caused by peritonitis of appendix perforation or intestinal obstruction. Some children may have constipation, and a few have diarrhea.
(3) Fever
The fever is usually low at first, not exceeding 38℃. Most of them have abdominal pain followed by fever. If the appendix is perforated, peritonitis or appendiceal abscess formation, there may be high fever. In addition, children may also have symptoms such as mental depression, drowsiness or anorexia.
2.Signs
(1) Systemic condition
Low fever may be present in the early stage. Late appendiceal perforation may show symptoms of toxicity, such as high fever and rapid and weak pulse. If vomiting is frequent, there may be dehydration and acidosis.
(2) Examination method
Before examining the abdomen, approach the sick child patiently to gain trust and cooperation. If appendicitis is suspected, the lower left abdomen should be examined first, followed by the upper left abdomen, upper right abdomen, and finally the lower right abdomen. During the examination, the abdomen should be first shallowly searched to understand the general situation and then deeply searched, and then the abdominal muscles on both sides should be compared to see if there is muscle tension and rebound pain. And must repeat the examination several times to clarify the site.
(3) Abdominal signs
Early manifestations are fixed pressure pain in the right lower abdomen, no tension or mild tension in the abdominal muscles, and the pressure pain points are not always located at the McKinsey point, and often change with the variation of the appendix position. The degree of abdominal muscle tension is also balanced with the severity of inflammation. If there is much intra-abdominal inflammatory exudate, the pressure pain is expanded in response. If diffuse peritonitis develops, whole abdominal tenderness and muscle tension may be present, but the right lower abdominal tenderness is still the most pronounced and may be accompanied by abdominal distension. Mobile turbid sounds may be present on percussion. Bowel sounds are diminished or absent. If an appendiceal abscess has formed, a painful mass can be found in the right lower abdomen, which is inactive, with indistinct margins in the early stage and clear borders in the late stage.
(4) Other physical signs
A positive rebound pain (Blumberg’s sign) indicates the presence of peritonitis; a positive colonic inflation test supports the diagnosis of appendicitis; a positive psoas major muscle test indicates that the appendix may be posterior; a positive closed-hole muscle test indicates a low appendix position (pelvic position).
(ii) Appendicitis in infants and children
Appendicitis in infants and children generally refers to children within 3 or 5 years of age, accounting for about 10% of the cases. The symptoms are atypical, the examination is uncooperative, the disease develops rapidly, and it is easy to be misdiagnosed. The rate of perforation is high.
1.Symptoms
(1) Abdominal pain
It is often manifested as crying and restlessness, but cannot point out the exact site of abdominal pain. When the abdomen is tapped or bumped, the crying intensifies and refusal to vibrate and tap occurs.
(2) Gastrointestinal symptoms
Early onset of vomiting, some infants and children vomiting can appear before the abdominal pain, initially reflex vomiting, later earth bile-like material. Vomiting can be frequent in diffuse peritonitis after perforation, and accompanied by abdominal distension. Diarrhea is more common in infants and children and can be due to irritation of the rectum by the pelvic appendix or intra-pelvic exudate.
(3) Fever
Early onset of the disease can have fever, some are high fever. 50% of the body temperature is above 38.5 ℃, in addition to irritability, lethargy, drowsiness, refusal to eat and other symptoms.
2.Signs
(1) General condition
High fever with symptoms of intoxication, mental depression, refusal to eat, pulse rate increased significantly, some children have dehydration and acidosis.
(2) Abdominal examination methods and signs
Infants and young children have weak abdominal wall muscles, muscle tension is not obvious. The examination should follow the principle of “first no pain (area) and then pain (area), first light pressure and then heavy pressure, compare both sides and repeat several times”. If the examination is still difficult, wait for the child to fall asleep or add sedation before examination. If the appendix is perforated, the abdomen is distended like a sphere, with pressure pain and muscle tension, and there may be signs of diffuse peritonitis such as mobile turbid sounds and diminished bowel sounds. In a small number of children, a periappendiceal abscess may be limited and a painful mass may be found in the right lower abdomen. Rectal palpation is of great diagnostic value in infants and young children with appendicitis, and a duplex examination can be performed, which shows right upper rectal tenderness and a palpable inflammatory mass. In children with peritonitis, right lower abdominal laparotomy is performed, and if purulent exudate is withdrawn, the diagnosis can be confirmed by picture microscopy.
(iii) Neonatal appendicitis
This type is rare, and there are only case reports in China. Due to the difficulty in diagnosis, the rate of perforation and mortality are high. The clinical manifestations are mainly crying, refusal of milk, fever and vomiting. The abdominal signs include abdominal distension and total abdominal pressure pain. Abdominal muscle tension is more difficult to appreciate. However, neonatal peritonitis may show erythema and even edema of the abdominal wall, bulging sounds on percussion, mobile turbid sounds, and loss of bowel sounds. Inflammatory exudate may be aspirated by laparotomy. In some children, free gas can be seen under the diaphragm on plain radiographs of the abdomen. It has been reported that congenital megacolon can be complicated by neonatal appendiceal perforation. It is also believed that neonatal appendicitis is a manifestation of necrotizing small bowel colitis in the appendix. The diagnosis of neonatal appendicitis should not be confirmed preoperatively, but is often confirmed intraoperatively by peritonitis dissection.
III. Treatment
(A) Surgical treatment
Indications for surgery
(1) Acute simple appendicitis, purulent appendicitis and gangrenous appendicitis
(2) Appendiceal perforation complicated by limited or diffuse peritonitis.
(3) Recurrent appendicitis.
(4) Acute attack of chronic appendicitis.
(5) Acute appendicitis caused by parasites.
Laparoscopic appendectomy
The application of laparoscopy in pediatric appendectomy has been carried out in China for a long time, which has advantages and disadvantages.
1. Advantages: laparoscopy can reduce the rate of appendiceal miscutting and facilitate comprehensive exploration of the abdominal cavity. The postoperative wound scar is small, which can reduce postoperative pain and shorten the hospital stay, and can also avoid the complications that may be caused by open surgery.
2.Disadvantages: For those with perforated appendix combined with peritonitis and serious adhesions, laparoscopic removal of appendix has some difficulties. The cost is higher.
(II) Non-surgical treatment
Indications
(1) Acute simple appendicitis with mild inflammation, and the patient has some reasons not to agree to surgery.
(2) Those who have limited periappendiceal abscess.