Secondary peritonitis in children

　　小儿继发性腹膜炎是由什么原因引起的：

　　1、周围血象白细胞计数及中性粒细胞比例一般皆有显著增高，但病情严重或机体反应低下时，白细胞计数并不高，仅有中性粒细胞比例升高或核左移及中毒颗粒出现。

　　2、血生化检查可发现酸中毒与电解质紊乱。

　　3、尿检尿液因失水而浓缩，可出现蛋白与管型，尿醋酮可呈阳性。

　　4、腹腔穿刺在诊断继发性腹膜炎时帮助很大，且有助于鉴别原发病见表1所示，腹腔渗液培养常可得致病的病原菌。

　　5、腹部X线检查可见肠腔普遍胀气，并有多个小气液面等肠麻痹征象，胃肠穿孔时，多数可见膈下游离气体存在（应立位透视），这在诊断上具有重要意义，影像学检查可通过X线或在腹腔镜下观察，X线片发现游离气体，多为胃肠道穿孔。

　　6、钡灌肠X线钡灌肠可见结肠空瘪，小肠有液面，对诊断阑尾炎和肠套叠有助，但如等钡剂通过破孔漏到已经感染的腹腔，能使感染加重，因此，如穿孔可能性很大时应避免钡剂检查，水溶性造影剂相对安全。

　　7、超声和CT不仅有助于检查肠道外腹腔内液体和气体，而且能发觉原发疾病，如阑尾炎或肠套叠。

　　小儿继发性腹膜炎可以并发哪些疾病：

　　常并发脱水，酸中毒，局限性脓肿，重者可并发感染性休克，发展成脓毒败血症，多脏器功能衰竭，腹膜炎的并发症和后果根据其起病时间可分为早期和晚期：

　　1、急性期（早期）在急性期常有菌血症，与需氧菌或厌氧菌有关，血行感染可导致休克和DIC，大部分源于细菌和内毒素作用，这种休克和多器官系统衰竭的复合作用与早期死亡率有关。

　　2、晚期晚期后果是脓肿形成，脓性物质可依解剖区域形成脓腔，如盆腔和膈下区域，也可发生粘连，引起血流动力学或神经压迫及阻塞，部分发生吻合口破裂，瘘管形成。

　　一、症状

　　1、腹痛：这是腹膜炎最主要的症状，疼痛的程度随炎症的程度而异，但一般都很剧烈，不能忍受，且呈持续性，深呼吸，咳嗽，转动身体时都可加剧疼痛，故病儿不愿变动体位，疼痛多自原发灶开始，炎症扩散后蔓延至全腹，但仍以原发病变部位较为显著。

　　2. Nausea and vomiting:This is a common early symptom, which starts with reflex nausea and vomiting caused by the stimulation of the peritoneum, with the vomit being gastric contents. In the later stage, when paralytic ileus occurs, the vomit turns yellow-green, containing bile, and even brownish fecal-like intestinal contents. Due to frequent vomiting, severe dehydration and electrolyte imbalance may occur.

　　3. Fever:Acute onset peritonitis may have a normal body temperature at first, and then gradually rise. In weak children, the body temperature may not necessarily rise with the progression of the disease. The pulse usually accelerates with the rise in body temperature. If the pulse accelerates while the body temperature decreases, it is often a sign of deterioration in the condition and effective measures must be taken early.

　　4. Infection and toxicity:When peritonitis enters a severe stage, it often presents with symptoms such as high fever, profuse sweating, dry mouth, rapid pulse, shallow breathing, and systemic toxic manifestations. In the later stage, due to the absorption of a large amount of toxins, patients may appear apathetic, emaciated, sunken eye sockets, cyanotic lips, cold limbs, yellow and cracked tongue, dry skin, rapid breathing, weak pulse, sharp rise or drop in body temperature, decreased blood pressure, shock, and acidosis. If the condition continues to worsen, death may occur due to liver and kidney failure and respiratory and circulatory failure.

　　Second, abdominal signs

　　1. Inspection:It is manifested as weakened or absent abdominal breathing, accompanied by significant abdominal distension. The exacerbation of abdominal distension is often an important sign for judging the progression of the disease.

　　2. Palpation:Pain and rebound tenderness are the main signs of peritonitis, which are always present and usually spread throughout the abdomen, with the primary disease focus being the most significant. The degree of abdominal muscle tension varies with the cause and the overall condition of the patient, and sudden and severe stimulation, such as chemical irritation caused by gastric acid and bile, can cause strong abdominal muscle tension, even presenting as 'wooden-like' rigidity, which is clinically called 'rigid abdomen'. However, in children or extremely weak children, abdominal muscle tension can be very mild and be overlooked.

　　3. Percussion:When the pain in the entire abdomen is severe and it is not easy to identify the location of the primary disease focus by palpation, gentle percussion of the entire abdomen often reveals significant percussion pain at the location of the primary disease focus, which is very helpful for localization diagnosis. Abdominal percussion may present as tympany due to gastrointestinal distension. When gastrointestinal perforation occurs, due to a large amount of free gas in the abdominal cavity, percussion in the supine position often reveals a reduced or absent liver dullness. When there is a lot of fluid in the abdominal cavity, it can produce mobile dullness, which can also be used for necessary localization of abdominal puncture.

　　4. Auscultation:Commonly found is a weakened or absent bowel sound.

　　5. Digital rectal examination:If the anterior fornix of the rectum is full and tender, it indicates the presence of pelvic infection.

　　Early appropriate treatment of intra-abdominal inflammatory diseases that may cause peritonitis is the fundamental measure to prevent peritonitis, such as preventing trauma and diagnosing and treating acute appendicitis as soon as possible, which can prevent the occurrence of secondary peritonitis. Any abdominal surgery, including abdominal puncture, should be performed strictly under sterile conditions; antibiotics should be administered orally before intestinal surgery, and appropriate catheter handling techniques should be adopted to reduce and lower the occurrence of peritonitis related to peritoneal dialysis.

　　1. Peripheral blood count

　　1. General condition:

　　The white blood cell count and the proportion of neutrophils are significantly increased.

　　2. In severe illness or low body response:

　　The white blood cell count is not high, only the proportion of neutrophils is elevated or there is left shift and toxic granules appear.

　　2. Blood biochemical examination

　　Acidosis and electrolyte imbalance may be found.

　　3. Urinalysis

　　Protein and casts may be present, and urinary acetone may be positive.

　　4. Peritoneal puncture

　　Cultures of peritoneal effusion often yield pathogenic bacteria.

　　5. Abdominal X-ray examination

　　1. The intestine is generally distended, with multiple small gas-liquid surfaces and other signs of intestinal paralysis.

　　2. When there is gastrointestinal perforation, free gas is often found below the diaphragm (should be examined in an upright position). This is of great significance in diagnosis.

　　3. Imaging examinations can be performed through X-ray or under laparoscopy. X-ray films show free gas, which is mostly due to gastrointestinal perforation.

　　6. Barium enema

　　Barium enema X-ray shows emptying of the colon and a liquid surface in the small intestine. It is helpful for diagnosing appendicitis and intussusception, but if the barium leaks into the already infected peritoneal cavity after passing through a perforation, it can worsen the infection.

　　7. Ultrasound and CT

　　It not only helps to examine extraintestinal peritoneal fluid and gas, but also can detect primary diseases, such as appendicitis or intussusception.

　　8. Percussion

　　1. When the entire abdomen is severely tender and it is difficult to identify the location of the primary focus using palpation, gentle percussion of the entire abdomen often reveals a significant percussive tenderness at the location of the primary focus, which is very helpful for localization diagnosis.

　　2. Abdominal percussion may present as tympany due to gastrointestinal distension. When there is gastrointestinal perforation, due to a large amount of free gas in the peritoneal cavity, percussion in the supine position often reveals a reduced or absent hepatic dullness. When there is a lot of fluid in the peritoneal cavity, it can produce a shifting dullness, which can also be used for necessary peritoneal puncture localization.

　　9. Auscultation

　　Commonly found is a weakened or absent bowel sound.

　　10. Rectal examination

　　If the anterior fornix of the rectum is full and tender, it indicates the presence of pelvic infection.

　　The dietary principles for children with secondary peritonitis mainly depend on different symptoms, with different dietary requirements. It is recommended to consult a doctor for specific dietary standards tailored to the specific condition.

　　1. Treatment

　　The treatment of acute secondary peritonitis should, in principle, be carried out as soon as possible, with surgery to handle the focus, resect necrotic tissue or repair perforations, and to aspirate and drain the pus in the peritoneal cavity. If the spreading peritonitis has been localized and the condition is trending towards improvement, conservative treatment should be performed. Thorough preparation should be made before surgery, and feverish patients should be cooled down. The specific arrangements should be determined according to the condition of the primary disease. The treatment of acute secondary peritonitis should, in principle, be carried out as soon as possible, and only in a few cases is non-surgical therapy allowed, which should quickly switch to surgical treatment if there is deterioration. The goal of treatment is to actively eliminate the causes of peritonitis and thoroughly clean and aspirate the pus and exudate in the peritoneal cavity, or to promote the rapid absorption and limitation of exudate, or to disappear through drainage. To achieve these goals, different treatment measures should be taken according to different causes, different stages of the disease, and different physical conditions of the patients.

　　1. General supportive therapy

　　(1) Correct hypovolemia and shock, maintain sufficient tissue perfusion and oxygen supply.

　　(2) Effective antibiotics: Secondary peritonitis is often a mixed infection of aerobic and anaerobic bacteria, so it is advisable to use broad-spectrum antibiotics or a combination of several antibiotics. If the pathogenic bacteria can be obtained, antibiotics selected based on the results of drug sensitivity tests are better.

　　(3) Support organ function.

　　(4) Supplement sufficient nutrition.

　　(5) Maintain water, electrolyte, and acid-base balance.

　　2. Surgical treatment

　　(1) Drain pus, eliminate the source of poisoning and shock.

　　(2) Locate the primary focus and treat it, such as removing a perforated appendix, gallbladder, draining the necrotic bile duct, removing necrotic intestinal tissue, removing necrotic gastrointestinal tumors, repairing duodenal perforations, etc.

　　(3) Prevent complications, flush the peritoneal cavity, and drain areas prone to abscess formation such as subphrenic, subhepatic, lesser omentum sac, and pelvic regions.

　　(4) Decompressive stenting, or create a jejunostomy for future enteral nutrition.

　　(5) Definite diagnosis.

　　II. Prognosis

　　Due to the progress in diagnosis and treatment levels, the prognosis of acute peritonitis has improved compared to the past. However, the mortality rate is still between 5% to 10%. Primary peritonitis occurring on the basis of liver cirrhosis ascites can even reach 40%. Poor prognosis is associated with delayed diagnosis, late treatment, and patients with heart, lung, kidney diseases and diabetes. Persistent peritoneal infection is due to residual infection foci, suture line openings, or undetected perforations, commonly leading to abscesses and occasionally to portal vein inflammation. Obstructions caused by incision hernias and intestinal adhesions are rare complications that may appear several years after surgery. Timely and correct diagnosis and treatment result in good prognosis for most patients.