Pancreatic abscess

　　Pancreatic abscess is caused by necrotic tissue from acute pancreatitis or secondary infection of pseudocysts, and can occur at any part of the pancreas. The main pathogenic bacteria are enteric bacteria. The abscess rupture and corrosion of adjacent organs can cause intestinal fistula or hemorrhage.

　　If not treated promptly, pancreatic abscess can lead to serious complications. Common complications include perforation of the transverse colon and hemorrhage in the lower gastrointestinal tract, massive intra-abdominal hemorrhage, and multiple intra-abdominal abscesses. The specific introduction is as follows:

　　1. Perforation of the transverse colon and hemorrhage in the lower gastrointestinal tract

　　It is one of the serious complications of pancreatic abscess, often occurring in the acute phase of the disease. The development process initially involves secondary infection and hemorrhage in the pancreatic abscess or pseudocyst, eventually leading to necrosis and perforation of the colon. The mortality rate is over 60%, and 85% of perforations occur in the transverse colon or sigmoid colon. The reasons are as follows:

　　(1) Thrombosis of mesenteric blood vessels in the colon due to pancreatic necrosis and infection.

　　(2) Digestive action of pancreatic enzymes.

　　(3) Necrotic hemorrhage of blood vessels in the pancreas or the wall of the abscess leads to a dramatic increase in intracavitary pressure within the abscess, compressing the colon wall and causing inflammation and infiltration damage.

　　(4) The blood supply to the sigmoid colon is naturally poor, and this segment of the colon is adjacent to the pancreas that is affected by the disease.

　　Clinically, it is first the occurrence of pancreatic abscess leading to colonic fistula, followed by hemorrhage and hematochezia. Clinical manifestations include high fever, exacerbation of abdominal pain, abdominal mass, and hematochezia. If there is significant hemorrhage, timely colostomy should be performed to temporarily divert and drain the abscess. Small colonic fistulas without hemorrhage can be cured by fasting and anti-infection.

　　2. Massive hemorrhage in the abdomen

　　Caused by invasion of abscess into blood vessels such as splenic artery, left gastric artery, or gastroduodenal artery, superior mesenteric vein, etc.

　　3. Multiple abdominal abscesses

　　Due to the spread of pancreatic abscess along the retroperitoneum to both sides, it can extend upwards to below the diaphragm and even the mediastinum, and downwards along the paracolic sulcus or below the psoas muscle to the inguinal region.

　　4. Complications with fistula

　　Duodenal fistula, jejunal fistula, gastric fistula, pancreatic fistula, etc.

　　5. Other

　　Gastric emptying delay; diabetes.

　　Pancreatic abscess can present in a concealed or explosive manner. At this time, the patient may present with persistent tachycardia, increased respiratory rate, intestinal paralysis, exacerbation of abdominal pain, accompanied by lumbar and back pain, elevated peripheral blood leukocytes, toxic symptoms in the patient, gradual rise in body temperature, occasional gastrointestinal symptoms (such as nausea, vomiting, and anorexia), and a few patients may have symptoms of diabetes.

　　Physical examination shows upper abdominal or whole abdominal tenderness, palpable mass. However, in a few patients, there may be no fever, only persistent tachycardia, mild anorexia, atelectasis, and mild liver function abnormalities. In the course of acute pancreatitis, if there are symptoms such as high fever, significant elevation and left shift of peripheral blood leukocytes, exacerbation of abdominal pain, abdominal mass, and systemic toxic symptoms, the possibility of pancreatic abscess should be suspected.

　　Serum amylase levels are elevated in 1/3 to 2/3 of cases. Liver function damage may occur, manifested by elevated serum transaminases and alkaline phosphatase, seen in about 40% of surviving cases and 60% of cases who die from pancreatic abscess. 40% to 48% of cases may have renal function damage, with increased serum urea nitrogen and creatinine. Chest X-ray examination in 35% of patients may show pneumonia, atelectasis, pleural reaction, pleurisy, or diaphragmatic elevation. Abdominal X-ray film may show localized retrogastric bubble sign, bubble sign between the stomach and transverse colon, extraintestinal gas with forward displacement of the stomach, and gas-liquid level in the lesser omentum.

　　The prevention of pancreatic abscess should include active treatment of biliary tract diseases, smoking cessation, and avoiding overeating and drinking. For infectious diseases, antibiotic treatment should be strengthened. This disease is a complication that occurs after acute pancreatitis or pancreatic injury. Therefore, the key to the prevention of this disease is to make an early diagnosis of acute pancreatitis or pancreatic injury and to make proper treatment in a timely manner.

　　Pancreatic abscess is formed by focal necrosis and liquefaction of necrotic pancreatitis or peripancreatic fat, followed by secondary infection. Clinical manifestations include persistent tachycardia, increased respiratory rate, intestinal paralysis, exacerbation of abdominal pain, accompanied by lumbar and back pain. The general examinations required for this disease are as follows:

　　1. Laboratory examination

　　The white blood cell count is significantly elevated, often reaching (20～50)×10^9/L, blood culture may show bacterial growth, and serum and urine amylase levels are persistently elevated, lasting for more than a week.

　　2. Imaging examination

　　(1) CT examination: CT images show the accumulation of fluid, especially the presence of gas in the accumulated fluid is a pathological feature of abscess formation, and the presence of gas in the abscess is the main indicator.

　　(2) B-ultrasound examination: B-ultrasound examination can show the presence, size, number, and location of pancreatic abscess, but it has certain limitations for severe acute pancreatitis.

　　(3) X-ray Thoracentesis: It can show the elevation of the left diaphragm, atelectasis of the left lower lung, and some may have significant pleural effusion.

　　(4) Abdominal X-ray: Many small bubble shadows are found in the pancreatic area, which is the small bubble sign or air-liquid cavity (caused by gas-producing bacteria in the abscess). In addition, there is also paresis of the transverse colon, and the air in the gastrointestinal tract presents a similar

　　(5) Gastrointestinal Barium Meal Examination: It can show the signs of pancreatic area enlargement, the widening of the duodenal ring, and the displacement of the stomach and transverse colon to varying degrees and directions according to the different locations and sizes of the abscess.

　　(6) Magnetic Resonance Imaging (MRI): It can show the signs of pancreatic enlargement and sparse blood vessels in the area of pancreatic abscess, but it is expensive.

　　The occurrence of pancreatic abscess indicates that the pancreas tissue has necrotic infection, which is closely related to enterobacteria. In the end, any human diet must pass through the intestines for excretion, so diet has a great impact on our condition. Below, we will introduce the dietary precautions for patients with pancreatic abscess.

　　1. Strengthening nutrition is something we all need to pay attention to

　　Many people diet to lose weight for a slim and attractive appearance, which ultimately leads to malnutrition. Moreover, the body's consumption after the occurrence of disease is very great: due to the consumption of the disease and the decrease in digestion and absorption function, most patients will experience malnutrition. Therefore, food should contain enough carbohydrates and foods rich in protein to supplement strength and improve immunity.

　　2. Healthy diet is very important, and it is also necessary to eat regularly

　　Food must be eaten at regular intervals and in proper amounts, choosing easily digestible foods. It is necessary to avoid greasy foods and not to overeat or binge. After suffering from a pancreatic abscess, the secretory function of the pancreas has been damaged to varying degrees, especially the digestive ability for fatty and protein foods has decreased. Some patients may still experience decreased appetite or characteristic fatty diarrhea after discharge. Therefore, if fat droplets are found in the stool, it is necessary to go to the hospital for a follow-up visit in a timely manner.

　　3. Pay attention to fasting

　　Patients with pancreatic abscesses are very prone to abdominal pain, so patients at this time must do a good job of fasting, waiting to eat after the symptoms disappear. If the symptoms do not disappear, it is necessary to go to the hospital for treatment in a timely manner to avoid the aggravation of the disease. Many patients often experience abdominal pain again after resuming their diet. In the past, it was necessary to wait for the patient's abdominal pain to disappear and the amylase in urine and blood to be completely restored to normal before starting to eat liquid food (such as congee, vegetable soup without oil, etc.). However, in clinical practice, it has been found that many patients have no symptoms or signs, but the amylase in urine and blood is still higher than the normal value, and it may take several months to return to normal. For such patients, we still allow the intake of liquid food, but it should be closely observed, and if there is any discomfort, go to the hospital for treatment at any time.

　　In recent years, there have been many discussions about the treatment of pancreatic abscesses, with significant differences in outcomes. The reason is that infectious pancreatic necrosis is included in the discussion of pancreatic abscesses, which has affected the evaluation of treatment. The treatment method must be surgical operation or drainage.

　　1. Percutaneous Drainage

　　Percutaneous puncture of the abscess under the guidance of ultrasound or CT, followed by the placement of a catheter for drainage, can be used as initial or single abscess accumulation treatment for pancreatic abscess, but the catheters placed percutaneously are thin, and it is difficult to drain the necrotic debris and thick pus. Often, multiple drainage catheters are needed, with a drainage success rate of 9% to 15%, so they cannot replace surgical drainage.

　　2. Surgical Treatment

　　The earlier the treatment of pancreatic abscess, the better the effect. Finding all abscesses and performing thorough drainage is a prerequisite for successful treatment. The main reasons for the persistence and recurrence of abscesses after surgery are often poor drainage.

　　Surgical treatment is usually debridement. The operation should fully expose the entire pancreas, duodenum, and retrocolonic area, and sometimes it is necessary to examine the root of the mesentery and the retroperitoneum. The main method of surgery is to remove necrotic tissue, and debridement should be thorough. As much as possible, the gray, brown, and black necrotic pancreas tissue should be removed. After debridement, the local area should be flushed, and cigars or drainage tubes should be placed in the omental sac and debridement sites for external drainage. Often, multiple drainage tubes and continuous lavage are needed, and the tubes should be sutured and fixed to the abdominal wall. Every day, the peritoneal cavity is flushed with normal saline and diluted antibiotic solution, often requiring thousands of milliliters of peritoneal lavage fluid until the lavage fluid is negative for bacteria on smears, and nursing and monitoring work should be done to close the abscess cavity as soon as possible.

　　The effectiveness of surgical treatment largely depends on whether the diagnosis is timely. If the diagnosis is delayed, the mortality rate often increases significantly. The cause of death is often sepsis caused by necrotic tissue, followed by etiology and complications. However, a successful operation, if necessary, can be operated on again, and postoperative drainage and lavage, active anti-infection and supportive treatment, are sure to cure the pancreatic abscess.