*2.3.4 Severity assessment*

Commonly used scoring systems (Ranson, modified Glasgow and pediatric acute pancreatitis severity) have demonstrated limited ability to predict disease severity in children and adolescents with acute pancreatitis. The sensitivity and negative predictive value of the above scores are insufficient to guide decision making in pediatric patients. Therefore better methods are needed for risk stratification. Anyway, in a logistic regression model [12], only white blood cell count at admission more than 18,500/mcL, trough calcium less than 8.3 mg/dL and blood urea nitrogen greater than 5 mg/dL appear to correspond independently with a poor outcome.

The lack of an accurate scoring system could cause delays in appropriate clinical management and increase the risk of progressive life-threatening complications. In recent years Suzuki [13] has investigated a modified score that reflects pediatric SIRS (systemic inflammatory response syndrome) score, age and weight (**Figure 3**) and it has proved a more adequate scoring system in children, helping to improve treatment outcome in these patients.


#### **Figure 3.**

*Japanese scoring system to assess severity of acute pancreatitis.*

#### *2.3.5 Complications*

The most frequent complication of acute pancreatitis in pediatric age is represented by the development of pseudocysts and occurs in 13% of patients (**Figure 4**). This is a delayed complication and occurs 4 weeks after the onset of the acute inflammatory process. Pseudocysts probably arise from disruption of the main pancreatic duct, leading to an oval fluid collection with a well-defined wall in the peripancreatic tissues. The early alteration that involves pancreatic tissue in the setting of an interstitial edematous pancreatitis (IEP) is the formation of peripancreatic fluid collections that may resolve spontaneously. A necrotizing process arising in the pancreatic parenchyma or in adjacent tissues results in the development of multiple necrotic collections walled-off with an increased risk of infection.

Vascular complications may involve the arterial or venous system and are caused by extravasated pancreatic enzymes with the loss of vessel wall integrity. Thus hemorrhage secondary to the rupture of a pseudoaneurysm or erosion of a major artery may occur. Moreover, in the venous system, thrombosis is a complication that commonly affects the splenic vein. Pancreatic ascites and pancreaticopleural fistulas are two uncommon types of internal pancreatic fistulas resulting from pancreatic duct disruption with leakage of pancreatic fluid. Since complications are similar to those occurring in adults the revised Atlanta classification (**Figure 5**) is useful in children too [11].

Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare in children with severe acute pancreatitis but still have high mortality rates.

The increased abdominal pressure leads to alteration in microvasculature determining ischemia, congestion and edema of the organs. Thus the consequent

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dysfunction syndrome [14].

**2.4 Treatment**

**Figure 5.**

**Figure 4.**

*2.4.1 Drug therapy*

bacterial shift into the bloodstream causes bacteremia, systemic inflammatory response and hemodynamic instability. The purpose of management of critical pediatric patients is to avoid ACS progression and the development of multi-organ

*peripancreatic fluid collection; ANC: acute necrotic collection; WON: walled-off necrosis.*

*Revised Atlanta classification of complications in AP. IEP: interstitial edematous pancreatitis; APFC: acute* 

Children with AP should be resuscitated with crystalloids and be provided 1.5–2 times maintenance intravenous fluids with monitoring of urine output

*Pediatric Pancreatitis: Not a Rare Entity DOI: http://dx.doi.org/10.5772/intechopen.85370*

*Pancreatic pseudocyst at contrast-enhanced CT scan in a 6-year old patient.*

*Pediatric Pancreatitis: Not a Rare Entity DOI: http://dx.doi.org/10.5772/intechopen.85370*

#### **Figure 4.**

*Pancreatitis*

*2.3.5 Complications*

*Japanese scoring system to assess severity of acute pancreatitis.*

**Figure 3.**

The most frequent complication of acute pancreatitis in pediatric age is represented by the development of pseudocysts and occurs in 13% of patients (**Figure 4**). This is a delayed complication and occurs 4 weeks after the onset of the acute inflammatory process. Pseudocysts probably arise from disruption of the main pancreatic duct, leading to an oval fluid collection with a well-defined wall in the peripancreatic tissues. The early alteration that involves pancreatic tissue in the setting of an interstitial edematous pancreatitis (IEP) is the formation of peripancreatic fluid collections that may resolve spontaneously. A necrotizing process arising in the pancreatic parenchyma or in adjacent tissues results in the development of multiple necrotic collections walled-off with an increased risk of infection.

Vascular complications may involve the arterial or venous system and are caused by extravasated pancreatic enzymes with the loss of vessel wall integrity. Thus hemorrhage secondary to the rupture of a pseudoaneurysm or erosion of a major artery may occur. Moreover, in the venous system, thrombosis is a complication that commonly affects the splenic vein. Pancreatic ascites and pancreaticopleural fistulas are two uncommon types of internal pancreatic fistulas resulting from pancreatic duct disruption with leakage of pancreatic fluid. Since complications are similar to those occurring in adults the revised Atlanta classification (**Figure 5**) is useful in children too [11]. Intra-abdominal hypertension (IAH) and abdominal compartment syndrome (ACS) are rare in children with severe acute pancreatitis but still have high mortal-

The increased abdominal pressure leads to alteration in microvasculature determining ischemia, congestion and edema of the organs. Thus the consequent

**72**

ity rates.

*Pancreatic pseudocyst at contrast-enhanced CT scan in a 6-year old patient.*

#### **Figure 5.**

*Revised Atlanta classification of complications in AP. IEP: interstitial edematous pancreatitis; APFC: acute peripancreatic fluid collection; ANC: acute necrotic collection; WON: walled-off necrosis.*

bacterial shift into the bloodstream causes bacteremia, systemic inflammatory response and hemodynamic instability. The purpose of management of critical pediatric patients is to avoid ACS progression and the development of multi-organ dysfunction syndrome [14].

#### **2.4 Treatment**

### *2.4.1 Drug therapy*

Children with AP should be resuscitated with crystalloids and be provided 1.5–2 times maintenance intravenous fluids with monitoring of urine output

over the next 24–48 h. Monitoring of patients with acute pancreatitis can provide indicators of complications arising, including SIRS and organ dysfunction/failure. Cardiac, respiratory, and renal status should be followed particularly closely within the first 48 h. Opioid analgesics in oral or parenteral forms are required for pain control in acute pancreatitis. Despite previous contentions, there is no evidence about the paradoxical contraction of the sphincter of Oddi induced by morphin and it should be used for acute pancreatitis pain not responding to acetaminophen or NSAIDs (non steroids anti-inflammatory drugs). In pediatric patients with a diagnosis of mild acute pancreatitis oral feedings or enteral nutrition (EN) can be started within 24–48 h. Parenteral nutrition (PN) should be considered in cases where EN is not possible for a prolonged period (longer than 5–7 days) such as in ileus, complex fistulae, abdominal compartment syndrome, to reduce the catabolic state of the body.

Antibiotics should not be used in the management of AP, except in the presence of documented infected necrosis, or in patients with necrotizing pancreatitis who are not improving clinically without antibiotic use. Antibiotics known to penetrate necrotic tissue (such as carbapenems, quinolones and metronidazole) should be used in management of infected pancreatic necrosis as these may delay surgical intervention and decrease morbidity and mortality. Instead antiprotease or antioxidants are not recommended in the management of acute pancreatitis in children [15].

#### *2.4.2 Nutritional strategy*

In severe pancreatitis an earlier oral re-feeding reduces the incidence of infections and contributes to a shorter hospitalization. Serum pancreatic enzymes' level tips the balance in the enteral feeding strategy. If serum amylase and lipase are decreasing liquid intake can be started, according with clinical conditions, while if they are minor than two times the upper normal values, an hypolipidic diet should be considered [13].

#### *2.4.3 Endoscopic and surgical treatment*

Undoubtedly anatomic abnormalities are an indication for surgery while ampulla of Vater anomalies or pancreatic divisum may be eligible for an endoscopic sphincterotomy. In patients with infected necrosis of the pancreatic gland a necrosectomy is mandatory in case of worsening clinical conditions and unresponsiveness to therapeutic measures. However this procedure (percutaneous, endoscopic or laparoscopic necrosectomy) has an high mortality rate and should be performed in hemodynamically stable patients.

Pancreatic pseudocysts are cysts that develop due to injury of the pancreatic duct and extravasation of fluid. These occur 4 weeks or later after the onset of pancreatitis. Treatment is indicated for pseudocysts if their size does not decrease, if they are accompanied by abdominal pain, or if there are complications of infection or hemorrhage. Whereas endoscopic ultrasound-guided transgastric drainage can safely be considered in case of growing pancreatic pseudocysts or in case of hemorrhagic complications [13].

### **3. Acute recurrent pancreatitis**

Approximately 10–20% of pediatric patients experience recurrent episodes of acute pancreatitis beneath which it is possible to identify an idiopathic or structural

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*Pediatric Pancreatitis: Not a Rare Entity DOI: http://dx.doi.org/10.5772/intechopen.85370*

gene and SPINK1-gene mutations.

**3.1 Etiology**

"idiopathic" is used.

*3.1.1 Genetic causes*

childhood.

*3.1.2 Anatomical anomalies*

sphincter hypertone [19].

*3.1.3 Metabolic disorders*

6-mercaptopurine) [17].

from acute pancreatitis in children [16].

etiology. ARP may evolve in the chronic form that is clinically indistinguishable

Risk factors that predispose to ARP can be categorized according the following frequency in: genetic, obstructive, metabolic and autoimmune [17]. However the etiology of ARP remains unexplained in 30% of cases and can be classified as

Genetic conditions that predispose to recurrent episodes of pancreatitis are the cystic fibrosis transmembrane conductance regulator-gene (CFTR-gene), PRSS1-

**CFTR-gene** mutations occur in about 5% of Western populations and cause an altered function of the product of this gene with a defect in the transmembrane epithelial chloride ion transfer. This dysregulation affects different organs including the pancreas and results in an abnormal production of viscous exocrine secretions that lead to ductal obstructions. Mutations in the cationic trypsinogen gene (**PRSS1-gene**) have been matched in patients with hereditary pancreatitis. The pancreas is unable to contrast an excessive trypsin activation because of the lack of protective mechanism predisposing patients to recurrent episodes of pancreatitis in

**SPINK1-gene** mutations predispose to the development pancreatitis and involve the serine protease inhibitor Kazal type I gene (SPINK1). This mutation results in a defect of the protective action in the pancreas mediated by SPINK1 protein that represents a feedback inhibitor of trypsin activation. Approximately 16–23% of patients with idiopathic pancreatitis have SPINK1 mutations instead [18].

Pancreas divisum is the most frequent anatomical variant and has an incidence

near to 12% in general population. As a result of this incomplete fusion of the ventral and dorsal ducts pancreatic juices cause ductal hypertension. Patients may experience recurrent pain after food intake, an alteration in serum content of pancreatic enzymes, or acute recurrent pancreatitis. Annular pancreas is another anatomical variant that may be related with duodenal or biliary obstructive symptoms. Ductal abnormalities such as a common pancreatico-biliary channel may determine a bile or pancreatic juices reflux and can be diagnosed with ERCP. Sphincter of Oddi dysfunction (SOD) is another factor predisposing to ARP and is probably the most common cause of the idiopathic form. This dysfunction includes two clinical forms: SO increased basal pressure related to a structural fibrotic alteration of the sphincter and SO dyskinesia, caused by

Toxic and metabolic factors such as hypercalcemia, hypertriglyceridemia, diabetes, porphyria and Wilson's disease can predispose to the development of acute recurrent episodes of pancreatitis as well as medications (i.e., azathioprine and

etiology. ARP may evolve in the chronic form that is clinically indistinguishable from acute pancreatitis in children [16].
