PANCREATIC DISORDERS
Embryologically, pancreas develops as an evagination from primitive duodenum and drains in it via a main duct, i.e. duct of Wirsung, though an accessory duct, i.e. duct of Santorini is also present in 15% population.
Physiologically, pancreas has endocrinal function to secrete insulin from islets of Langerhans as well as exocrine function to secrete over twenty digestive and absorptive enzymes, e.g. lipase (for fat), trypsin and chymotrypsin (for proteins). Clinical features of malabsorption appear only after ~90% of pancreatic activity is lost. Pancreatic enzymes, specially lipase, are low in newborns, leading to poor fat tolerance in them.
Exocrinal pancreatic insufficiency is commonly seen in cystic fibrosis, though other causes include pancreatitis, severe malnutrition, Schwachman syndrome (neutropenia, failure to thrive and malabsorption) and inherited enzyme deficiencies.
Acute pancreatitis in children is usually caused by: (a) viral infections, e.g. mumps, (b) blunt abdominal trauma, or (c) drugs, e.g. antiretrovirals agents.
Clinically, it presents with acute epigastric pain, persistent vomiting, fever and significant fluid-electrolyte imbalance. Acute hemorrhagic pancreatitis, seen in adults with shock, is rare in children.
Diagnosis depends on the presence of any two of the following three findings: (a) abdominal pain compatible with pancreatic origin, (b) elevation of serum amylase/ lipase gt;3 times of the upper normal limit, and (c) imaging studies suggestive of acute pancreatitis. Presence of organ failure, e.g. respiratory distress, shock, DIC and renal failure suggests moderate to severe disease.
Management is mainly conservative with nasogastric suction, fluid and electrolyte correction and pain relief with NSAIDs or paracetamol. Antibiotics are not required except in acute infected necrotizing pancreatitis and surgery is rarely indicated in acute phase, except to drain an abscess.
Uncomplicated cases usually recover in 3-4 days.However, many children are prone for recurrent pancreatitis, i.e. more than two episodes with at least one-month symptom-free interval.
Pseudocyst of pancreas is a sequel of acute pancreatitis, though uncommon in children. These cases present with palpable abdominal mass with/without ascites or jaundice, after 2-4 weeks of acute illness. Diagnosed on USG/CT, no treatment is necessary for small lesions, while large pseudocysts need percutaneous or laparoscopic drainage.
Chronic or recurrent pancreatitis in children may be idiopathic, e.g. juvenile tropical pancreatitis or secondary to autoimmune, hereditary (cystic fibrosis) or metabolic disorders or congenital malformations. Many of them present with fat malabsorption (exocrine dysfunction) or diabetes mellitus (endocrinal dysfunction).
Diagnosis of chronic pancreatitis requires suggestive imaging finding, e.g. altered echotexture of pancreas with/ without calcifications and dilatation, strictures or calculi of the pancreatic duct, along with one of the following three criteria: (a) abdominal pain consistent with pancreatic origin, (b) evidence of exocrine pancreatic insufficiency, or (c) evidence of endocrinal pancreatic insufficiency.
Etiological evaluation also includes sweat chloride test, USG/CT, magnetic resonance cholangiopancreatography (MRCP) and endoscopic retrograde cholangiopancreatography (ERCP).
Treatment depends on the cause, along with supportive therapy, oral pancreatic enzyme replacement and management of diabetes. Endoscopic treatment may be required for pseudocysts, ductal lesions and calculi.
Juvenile tropical pancreatitis is the commonest cause of chronic pancreatitis in children or adolescents of developing countries. In India, maximum cases have been reported from Kerala, though the incidence has declined in recent years.
Etiology is uncertain, probably related to pancreatic injury in malnutrition, trace-element deficiencies, e.g. Vitamin A, C, zinc, copper, manganese, selenium; or consumption of an unidentified substance in cassava tapioca-staple diet in endemic areas.
Clinically, these cases present with recurrent abdominal pain in childhood and pancreatic calculi and/or diabetes mellitus in adolescence. While persistent steatorrhea is uncommon due to poor dietary intake in affected population, fat intolerance is obvious on excessive intake. On examination, these children are typically emaciated with distended abdomen, parotid enlargement and sometimes, a cyanotic hue on lips.
Diagnosis is often missed as functional abdominal pain, till pancreatic calculi are visible on abdominal X-rays. Confirmation requires USG/ CT/MRI and ERCP (dilated pancreatic duct).
Treatment is largely supportive including avoidance of fat in diet, oral pancreatic enzyme replacement and management of Diabetes. Endoscopic treatment may be required for ductal lesions and calculi.
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