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Hypothyroid case
Cardiac Pharmacology: Anti-arrhythmia Drugs
Initial Antimicrobial Therapy
Pharmacology of the Autonomic Nervous System
Electrical Injuries


A. Annular Pancreas/Pancreas Divisum

The pancreas develops from an anterior and posterior anlage of the foregut early during gestation (28 days). The anterior bud leads to the liver and body and tail of the pancreas. The posterior diverticulum develops into the head of the pancreas. This bud rotates anteriorly and later fuses to achieve the relationship to the rest of the pancreas. Development of the pancreas in embryonic life requires a trophic stimulus from the associated mesenchyme. Under the influence of this mesenchyme the mature organ develops, being mainly composed of ductal, exocrine and endocrine cells. Exocrine and ductal pancreas is derived from the endoderm of the foregut. Recent evidence suggests that the endocrine cells derive also from the endoderm of the foregut as evidenced by the expression of the genes responsible for hormonal production. This challenges the theory that endocrine cells may originate from the neural crest cells (neuroectodermal) of the embryo reinforced by the enunciation of the amine precursor uptake decarboxylase (APUD) theory.

Annular pancreas is the most common congenital malformation of the pancreas in association with duodenal atresia. Embryologically the ring formation (annulus) originates from the ventral pancreas primordium (Lecco's theory). The pancreatic duct of the annular tissue passed from the anterior portion to the lateral and posterior portion finally joining with the main pancreatic duct. Two types of annular pancreas are recognized: 1) Extramural ‑ causing high gastrointestinal obstruction; vomiting is the most common presenting symptom, and 2) Intramural ‑ producing duodenal ulceration. Presentation at birth is affected by the degree of duodenal obstruction and coexistent anomalies. Polyhydramnios usually accompanies complete high intestinal obstruction in annular pancreas. Associated anomalies can range from malrotation, intrinsic duodenal obstruction, Down syndrome and duodenal bands. ERCP is the most important procedure to find the characteristic features and establish the therapeutic strategy in cases of annular pancreas. Experience militates against any direct attack on the offending annulus. Therefore, all children with this abnormality are generally treated with a bypass procedure, preferably a duodeno‑duodenostomy. Long‑term complications may include cholestatic jaundice, upper gastrointestinal motility disorder, failure to thrive, chronic diarrhea and chronic relapsing pancreatitis due to an incomplete divisum anomaly.

Pancreas divisum (PD), believed the most common congenital anomaly of the pancreas, is an embryologic variation of pancreas development where the dorsal (Santorini) and ventral portions (Wirsung) ducts drain separately. Diagnosis is made with ERCP (short duct of Wirsung that does not communicate with main pancreatic duct of Santorini). Not everybody with this ductal anomaly develops pancreatitis. Likewise with the minor papilla draining the bulk of the pancreas in PD, a small orifice size (< 0.75 mm) plays a role in outflow obstruction and development of pancreatitis. Children with PD and recurrent episodes of pancreatitis will need endoscopic sphincterotomy of the minor and sometimes major papilla. If not feasible technically, surgical sphincteroplasty of both papillae along with cholecystectomy (bile stasis leads to gallstones) is indicated. Intraoperative pancreatogram will help determine if both papillas are stenotic. Once chronic pancreatitis is established, ductal drainage or resection may be necessary.

B- Pancreatitis

1. Acute Pancreatitis

Acute pancreatitis (AP) is unusual in the pediatric patient, can affect all age groups and should be considered in children presenting with acute abdominal complaints Causes are diversely and clinical course less severe. The three most common etiological factors are: trauma, drug‑induced, and biliary tract disorders. Other factors to consider are: infections (mumps, ascaris, adenovirus), metabolic (branched‑chain organic acidemias), structural defects (anomalous union of pancreatico‑biliary ductal system), and hereditary. Blunt abdominal trauma is the leading cause (20‑30%) of AP by crushing the fixed organ between the spine. Drugs associated to the development of AP are: steroids, L‑asparaginase, valproic acid, acetaminophen (drug withdrawal is treatment of choice). Biliary disorders related to AP are gallstone and choledochal cysts by causing transient ductal obstruction. Most common complaint of children with AP is abdominal pain. Diagnosis is confirmed with elevated amylase/lipase in serum and urine (lipase is more specific since pancreas is major source). Imaging studies of utility are US, CT‑Scan and ERCP. The use of ERCP in previously idiopathic cases of AP have increased the yield of diagnosing anomalous pancreatico‑biliary junctional defects. Management during early phase is supportive with IV therapy, NG decompression, NPO (to decrease acid stimulation and prevent secretin release), and nutritional (TPN). Surgery is rarely required except complications such as abscess and pseudocyst formation.

Uncommon disorder in childhood. Trauma (compressed injury against spinal column) and biliary tract disorders (choledochal cyst, cholelithiasis) are most common cause of pancreatitis. The most common congenital ductal anomaly leading to pancreatitis is pancreas divisum. Most common complaint is mid-epigastric abdominal trauma associated with nausea and vomiting. Diagnosis is confirmed with elevated levels of amylase and lipase. Ultrasound is useful to determine degree of edema and presence of pseudocyst formation. Treatment consists of: NPO, NG decompression, decrease acid stimulation (H-2 blockers), aprotinin, glucagon, and anticholinergics. Pain is relieved with meperidine. When pancreatic serum enzymes level return to near normal level patient is started in low-fat diet. Antibiotic prophylaxis use is controversial. Surgery is indicated for: abscess formation and pseudocyst. Pseudocysts are the result of major ductal disruptions or minor lacerations. Observation allows spontaneous resolution in 40-60% of cases. Percutaneous aspiration and catheter drainage is another alternative in management. Follow-up studies permit determine if cavity is decreasing in size. This can be done outpatient teaching parents to irrigate the catheter at home to assure patency. Persistency beyond 6 months may need resectional therapy. Additional option is internal drainage (cyst-gastrostomy, cyst-jejunostomy). Abscess should be drained and debride.

Pancreatic pseudocyst formation is an uncommon complication of pancreatic inflammatory disease (pancreatitis) or trauma in children. More than half cases are caused by blunt abdominal trauma. Ultrasound is the most effective and non‑invasive way of diagnosing pancreatic pseudocysts. Acute pseudocysts are managed expectantly for 4‑6 wk. until spontaneous resolution occurs. 25‑50% will undergo spontaneous resolution. Medical therapy consists of decreasing pancreatic stimulation and giving nutritional support. Rupture is the major complication of conservative management. Chronic pseudocysts (> three mo.) will benefit from prompt operation and internal drainage since resolution is rare. Percutaneous catheter drainage under local anesthesia using Ultrasound or CT guided technique is an appropriate method of first‑line therapy for non‑resolving (chronic) or enlarging pancreatic pseudocysts. The approach is transgastric or transcutaneous. Those cysts that fail to resolve with percutaneous drainage should go investigation of ductal anatomy to rule out disruption of the main pancreatic duct. The need for further surgery (drainage or resectional) will depend on the status of the duct of Wirsung. 

2. Chronic Pancreatitis

Chronic pancreatitis is an unusual condition seen in children. In contrast to adults, chronic pancreatitis has significant lifelong morbidity. Most common etiology of chronic pancreatitis in children consists of trauma, cystic fibrosis, hyperparathyroidism, hyperlipidemia, aminoaciduria, hereditary, congenital ductal anomalies and choledochal cyst. Main symptoms are recurrent abdominal (epigastric) pain associated with nausea and vomiting.  A transient elevation of amylase and lipase is associated with the pain. Once the diagnosis of chronic pancreatitis is suspected, the anatomy of the pancreatic duct should be defined using ERCP or MRCP (less invasive). In chronic pancreatitis, the pancreatic duct is frequently dilated with one or more obstructive lesions. Ongoing attacks of pancreatitis may lead to diabetes, steatorrhea and pancreatic stones. Early endoscopic sphincterotomy can slow the progressive nature of the disease and has been suggested as initial choice of treatment.  With continued symptoms, lateral pancreaticojejunostomy (Puestow procedure) in dilated and obstructed ductal anatomy has been found to decrease significantly the pancreatitis episodes, relieve the recurring abdominal pain and arrest the progression of exocrine and endocrine insufficiency. Recently, the Frey procedure adding pancreatic head coring to the pancreaticojejunostomy has provided pain relieve in more than 85% of children with chronic pancreatitis.

C. Hepatic Cysts

Hepatic cysts (HC) can be either parasitic (echinococcal) following infestation in endemic regions, acquired (after trauma or inflammatory processes), or nonparasitic (congenital) in nature. Congenital nonparasitic HC are uncommon, solitary, benign lesions that arise from aberrant development of intrahepatic biliary radicals after ischemic thrombo‑embolic phenomena (vascular disruption theory). The cyst is lined with cuboidal or squamous epithelium, and there is a female and white children predominance. Although generally asymptomatic, children may manifest increased abdominal girth, vague abdominal discomfort, infection, or obstructive jaundice. Ultrasound and CT‑Scan are diagnostic tools. Management may consist of: simple unroofing, complete removal by enucleation or hepatic lobectomy, internal roux‑en‑Y drainage, or percutaneous aspiration and sclerosis (alcohol, minocycline). The surgical alternative to use will depend on size, location (central, peripheral or dumbbell), and presence of communication with biliary system of the cyst (see figure). Some cases diagnosed prenatally or during the neonatal period have undergone slow spontaneous regression.

D. Biliary Atresia

Persistent conjugated hyperbilirubinemia (greater than 20% of total or 1.5 mg %) should be urgently evaluated. Initial evaluation should include a well‑taken history and physical exam, partial and total bilirubin determination, type and blood group, Combsí test, reticulocyte cell count and a peripheral smear.

Cholestasis means a reduction in bile flow in the liver, which depends on the biliary excretion of the conjugated portion. Reduce flow causes retention of biliary lipoproteins that stimulates hypercholesterolemia causing progressive damage to the hepatic cell, fibrosis, cirrhosis and altered liver function tests.

Biliary Atresia (BA) is the most common cause of persistently direct (conjugated) hyperbilirubinemia in the first three months of life. It is characterized by progressive inflammatory obliteration of the extrahepatic bile ducts, an estimated incidence of one in 15,000 live births, and predominance of female patients. The disease is the result of an acquired inflammatory process with gradual degeneration of the epithelium of the extrahepatic biliary ducts causing luminal obliteration, cholestasis, and biliary cirrhosis.  The timing of the insult after birth suggests a viral etiology obtained transplacentally. Almost 20% of patients have associated anomalies such as: polysplenia, malrotation, situs inversus, pre-duodenal portal vein and absent inferior vena cava. Histopathology is distinguished by an inflammatory process in several dynamic stages with progressive destruction, scar formation, and chronic granulation tissue of bile ducts. Physiologic jaundice of the newborn is a common, benign, and self-limiting condition.

In BA the patient develops insidious jaundice by the second week of life. The baby looks active, not acutely ill and progressively develops acholic stools, choluria and hepatomegaly. Non-surgical source of cholestasis shows a sick, low weight infant who is jaundiced since birth. The diagnostic evaluation of the cholestatic infant should include a series of lab tests that can exclude perinatal infectious (TORCH titers, hepatitis profile), metabolic (alpha-1-antitrypsin levels), systemic and hereditary causes. Total bilirubin in BA babies is around 6-10 mg%, with 50-80% conjugated. Liver function tests are nonspecific. Lipoprotein-X levels greater than 300 mg% and Gamma Glutamyl Transpeptidase (GGT) above 200 units% suggest the diagnosis. The presence of the yellow bilirubin pigment in the aspirate of duodenal content excludes the diagnosis of BA. Ultrasound study of the abdomen should be the first diagnostic imaging study done to cholestatic infants to evaluate the presence of a gallbladder, identify intra or extrahepatic bile ducts dilatation, and liver parenchyma echogenicity. The postprandial contraction of the gallbladder eliminates the possibility of BA even when nuclear studies are positive. Nuclear studies of bilio-enteric excretion (DISIDA) after pre-stimulation of the microsomal hepatic system with phenobarbital for 3-5 days are the diagnostic imaging test of choice. The presence of the radio-isotope in the GI tract excludes the diagnosis of BA. Percutaneous liver biopsy should be the next diagnostic step. The mini-laparotomy is the final diagnostic alternative. Those infant with radiographic evidence of patent extrahepatic biliary tract has no BA. Medical management of BA is uniformly fatal. Kasai portoenterostomy has decreased the mortality of BA during the last 30 years. Kasai procedure consists of removing the obliterated extrahepatic biliary system, and anastomosing the most proximal part to a bowel segment. Almost three-fourth of patients will develop portal hypertension in spite of adequate postoperative bile flow. They will manifest esophageal varices, hypersplenism, and ascites. Hepatic transplantation is reserved for those patients with failed portoenterostomy, progressive liver failure or late-referral to surgery.

E. Biliary Hypoplasia

Biliary hypoplasia is a rare cause of persistent neonatal conjugated hyperbilirubinemia. Pathologically, affected children have absent or reduced number of bile ductules with normal distribution of branches of the portal vein and hepatic artery within the liver parenchyma. Biliary hypoplasia is also identified as paucity of interlobular bile ducts (PILBD). Two types of PILBD are recognized: 1) syndromic (arteriohepatic dysplasia or Alagille's syndrome) with characteristic extrahepatic abnormalities (fascial appearance, pulmonic artery stenosis, vertebral anomalies, embryotoxon and delayed weight‑height development), and 2) non‑syndromic biliary hypoplasia. Biliary hypoplasia is clinically indistinguishable from biliary atresia and can sometimes be confused. A definitive diagnosis is difficult to make in early infancy. Differentiation between biliary atresia, hypoplasia and neonatal hepatitis continues to require direct visualization of the biliary ducts. This mean laparoscopic or open intra‑operative cholangiography and liver biopsy. The cholangiogram will show diminutive intra‑ and extra‑hepatic biliary tree. Attempts to establish biliary flow by means of hepatic porto‑enterostomy (Kasai procedures) in children with PILBD have been unsuccessful and contraindicated. Management is conservative and include predigested formulas, ursodeoxycholic acids (10 mg/kg/day), phenobarbital and A, D, K, E vitamin replacement. Non‑syndromic PILBD have better long‑term prognosis. Children with syndromic PILBD identified in infancy because of cholestasis have a 50% probability of long‑term survival without liver transplantation.

F. Choledochal Cyst & Choledochocele

Choledochal cyst is a rare dilatation of the common bile duct, prevalent in oriental patients (Japan), where >60% of patients are less than 10 years old. The etiology is related to an abnormal pancreatic-biliary junction (common channel theory) causing reflux of pancreatic enzymes into the common bile duct (trypsin and amylase). Symptoms are: abdominal pain, obstructive jaundice, a palpable abdominal mass, cholangitis, and pancreatitis. Infants develop jaundice more frequently, causing diagnostic problems with Biliary Atresia. Older children may show abdominal pain and mass. Jaundice is less severe and intermittent. Diagnosis is confirmed with Ultrasound and corroborated with a HIDA (or DISIDA) Scan. Choledochal cysts are classified depending on morphology and localization. Management is surgical and consist of cyst excision and roux-en-Y hepatico-jejunostomy reconstruction. Cyst retention penalties paid are: stricture, cholangitis, stone formation, pancreatitis, biliary cirrhosis, and malignancy. Long-term follow-up after surgery is advised.

In 1985, a new variant of choledochal cyst known as forme fruste was described in the pediatric literature. Forme fruste choledochal cyst (FFCC) is characterized by minimal dilatation of the extrahepatic bile duct which does not grow with time. The normal diameter of the common bile duct in children ranges between two and 6 mm. FFCC is associated with a diameter above six mm and below 10 mm. Most patients with FFCC have a long common channel, in which the common bile duct-pancreatic duct junction is away from the duodenal papilla, with partial obstruction of the terminal common bile duct. FFCC is associated with fever, jaundice, abdominal pain, recurrent pancreatitis and altered liver function tests. Histologically FFCC demonstrates thickened fibrous connective tissue, absent muscular layer with flattened, ulcerated and dysplastic mucosa. Diagnosis is established with ultrasound. ERCP or better yet MRCP can help delineate the anatomy and presence of a long common pancreaticobiliary channel in FFCC. Management consists of cyst excision and Roux-en-y hepaticojejunostomy. Due to the small size the anastomosis is technically difficult and should be performed carefully to avoid stricture and postoperative cholangitis. To maintain ductal anastomosis patency it is imperative that diseased ductal tissue not be incorporated in the anastomosis, the circumstance most likely responsible for the high incidence of anastomotic stricture in choledochal cyst past drainage operations.

Choledochocele is an extremely rare variant of choledochal cysts classified as type III by Alonso-Lej. The cystic dilatation occurs in the distal portion of the common bile duct most commonly in an intrapancreatic fashion protruding toward the duodenum. Patients with choledochocele can develop intermittent colic abdominal pain, obstructive jaundice and recurrent bouts of pancreatitis. Nearly half of the patients have previously undergone cholecystectomy. Diagnosis is suggested by ultrasonography and confirmed with HIDA scan, MRCP or ERCP. In the most common variety the ampulla opens into the choledochocele which in turns communicates with the duodenum via another small opening. Cyst distension explains the episodes of colicky pain. Adenocarcinoma has been reported arising from choledochocele, though some researchers believe choledochocele does not share the strong premalignant potential of the more common types of choledochal cysts. The mucosa lining of choledochocele is usually duodenal, arguing that the cyst is a duodenal duplication. Successful endoscopic management (papillotomy) of choledochocele has been reported when the lesion is small. Surgical management entails excision of the duodenal luminal portion of the cyst leaving the medial portion containing the ampulla intact. Prognosis after surgery is good.

G. Cholelithiasis, Choledocholithiasis, Gallbladder Hydrops & Gallstone Ileus

With the increase use of sonography in the work-up of abdominal pain, cholelithiasis is diagnosed more frequent in children. Gallstones occur as consequence of loss of solubility of bile constituents. Two types are recognized: cholesterol and bilirubin. Those of cholesterol are caused by supersaturation of bile (lithogenic) by cholesterol overproduction or bile salt deficiency. Bilirubin stones occur due to hemolysis (Sickle Cell, thalassemia) or bacterial infection of bile. Other etiologies include: Ascaris Lumbricoides infestation, drug-induced (Ceftriaxone), ileal resection, TPN. etc. Gallbladder sludge is a clinical entity that when it persists can be a predisposing factor for cholelithiasis and cholecystitis.

Laparoscopic Cholecystectomy (LC) has become the procedure of choice for the removal of the disease gallbladder of children. The benefit of this procedure in children is obvious: is safe, effective, well tolerated, it produces a short hospital stay, early return to activity and reduced hospital bill. Several technical differences between the pediatric and adult patient are: lower intraabdominal insufflation pressure, smaller trocar size and more lateral position of placement. Complications are related to the initial trocar entrance as vascular and bowel injury and those related to the procedure itself; bile duct injury or leak. Three 5 mm ports and one 10 mm umbilical port is used. Pneumoperitoneum is obtained with Veress needle insufflation or using direct insertion of blunt trocar and cannula. Cholangiography before any dissection of the triangle of Calot is advised by some workers to avoid iatrogenic common bile duct injuries during dissection due to anomalous anatomy, it also remains the best method to detect common bile ducts stones. Treatment may consist of: (1) endoscopic sphincterotomy, (2) opened or laparoscopic choledochotomy, or (3) transcystic choledochoscopy and stone extraction. Children with hemolytic disorders, i.e. Sickle cell disease, have a high incidence of cholelithiasis and benefit from LC with a shorter length of postop stay and reduced morbidity.

Cholelithiasis is a frequent complication of Sickle Cell Disease (SCD) in children. Prevalence of developing pigmented stones can range from thirty to 50%. Even the prevalence of developing common bile duct stones in children with SCD is higher than the general population. Complications related to cholelithiasis include biliary colic, pancreatitis, cholecystitis and obstructive jaundice. Children with SCD should be screened for cholelithiasis since the age of eight years using abdominal ultrasound. Once cholelithiasis is identified removal of the sick gallbladder should be accomplished regardless if the child is asymptomatic or not. Preoperative transfusion reduces the morbidity of the surgical procedure.  Elective laparoscopic cholecystectomy should be the gold standard in children with SCD and asymptomatic cholelithiasis to prevent the potential complications of biliary colic, acute cholecystitis, and choledocholithiasis, which lead to major risks, discomfort, and longer hospital stay. A laparoscopic cholecystectomy result in a shorter hospital stay with fewer postoperative complications than open operation in patients with sickle cell disease and is the procedure of choice in the treatment of cholelithiasis in such patients.

Acalculous cholecystitis (AC) is more commonly found in children than adults. Two‑third of cases appear as a complication of other illness: trauma, shock, burns, sepsis, and operative procedures. Contributing causes mentioned are: obstruction, congenital tortuosity or narrowing of the cystic duct, decreased blood flow to the gallbladder, and long‑term parenteral nutrition. Males are more commonly affected than females. Fever, nausea, vomiting, diarrhea, dehydration and marked subhepatic tenderness are the most common symptoms. Other less common sx are jaundice, and abdominal mass. Labs show leucocytosis and abnormal liver function tests. Recently (APSA 95), two distinct forms of this disease have been recognized: acute, with symptom duration less than one month and chronic, with sx greater than three months. US is diagnostic by demonstrating hydrops of gallbladder, increase wall thickness and sludge. HIDA scan with CCK stimulation may help diagnose chronic cases. In both situations management consist of early cholecystectomy which can be executed using laparoscopic techniques.

Laparoscopic cholecystectomy (LC) has replaced the open procedure as the treatment of choice in gallbladder disorders. With the lap technique an increase two- to threefold in the incidence (0.5%) of bile duct injuries (BDI) has also occurred. Inappropriate anatomy identification and aberrant situations are the most common cause of BDI. BDI can be classified into transection, lacerations, leaks or strictures. Disease complexity, increasing age, male gender and admission to a teaching hospital are associated with an increase risk of injury. Classic injuries involve clipping & dividing the CBD for the cystic duct. Other BDI may result from stenting injury, thermal injury; lose cystic duct clip or an accessory 'Luschka' duct. Such injuries cause two principal clinical manifestations: 1) bile leaks with pain and secondary bile peritonitis, and 2) biliary obstruction due to partial or complete hepatic or common duct ligation (jaundice) or late stricture formation. US, HIDA scan or CT-Scan followed by ERCP or PTC may help diagnosed and define the exact location and nature of the BDI. Complete proximal obstruction may need transhepatic biliary catheters in each radical duct to relieve obstruction. A bile leak may need percutaneous drainage for sepsis control. Cystic or accessory ducts leaks can be dealt with endoscopic ampullary stenting or re-laparoscopic ligation if identified early. The most effective means of reconstructing a major BDI is using roux-en-y hepaticojejunostomy after inflammation and adhesions of the initial insult have subsided. Intraoperative cholangiography appears to protect against BDI by preventing misidentification of anatomy. Conversion to open cholecystectomy is essential in avoiding these injuries when the anatomy remains uncertain.

The finding of gallstones in neonates and infants is no longer rare. With the widespread use of abdominal sonography in a growing population of prematures TPN-fed survivals more cases of cholelithiasis in infants are reported. Stone formation increases with the duration of TPN. Other lithogenic factors are prolonged fasting, ileal resection, cystic fibrosis, polycythemia, multiple blood transfusions and inflammatory bowel disease. Approximately 80% of gallstones in children are not due to hemolytic disease. Clinically, the symptomatic infant with gallstone can develop colicky abdominal pain, postprandial nausea/vomiting, fatty-food intolerance and failure to thrive. Severe complications are seen in almost one-third of the infants with gallstones including jaundice by common bile duct obstruction, pancreatitis and perforation with bile peritonitis. Surgery is the treatment of choice for infants presenting with symptomatic cholelithiasis. Resolution of gallstones is seen in most asymptomatic infants between six months and one year of oral intake justifying a period of observation. Ursodeoxycholic acid is not effective in the treatment of pigmented stones. Laparoscopic cholecystectomy is recommended for the asymptomatic child younger than three years of age when echogenic shadows have been present for at least 12 months following resumption of oral feedings or when the gallstones are radiopaque (calcified).

A polypoid lesion identified in the gallbladder of a child is a very rare event. It represents an elevated lesion of the mucosal surface of the gallbladder which in most instances causes parental concern. Fortunately, most polypoid lesions identified in gallbladders are benign (90%). Histologically they are adenomatous, hyperplastic, gastric heterotopia or cholesterol polyps. The prevalence of such polyps is greater among males and obese children. Ultrasonography is the image method of choice in diagnosing gallbladders polyps in children and adults. They are seen as pedunculated or sessile echogenic lesions attached to the gallbladder wall protruding toward the lumen and fixed in changed of posture. Gallbladder polyps can be associated with acalculous cholecystitis. Lesions smaller than 10 mm do not progress to malignancy or development of stones, and none produces symptoms or complications of biliary disease. Surgical management of gallbladder polyps is indicated when the size of the polypoid lesion is above 10 mm in diameter, when associated with gallstones and when the child has consistent biliary symptoms. Treatment consists of laparoscopic cholecystectomy. Asymptomatic small polyps (< 10 mm) should be maintained under ultrasonographic surveillance.

Common bile ducts stones (choledocholithiasis) are usually secondary stones from the gallbladder that migrate through the cystic duct causing acute or chronic biliary tract obstruction (obstructive jaundice), pancreatitis or cholangitis.  Most common bile duct stones in children pass spontaneously without significant complications. Rarely, children can also develop primary common bile ducts stones. Up to 15% of children harboring gallstones can harbor asymptomatic common bile duct stones. Recurrent right upper quadrant pain is the most common clinical presentation. Most children have idiopathic gallstones. Ultrasound is the first study which will reveal whether the child has common bile duct dilatation with the presence of stones. This is accompanied with measurement of liver function tests and pancreatic enzyme. Once dilatation of the common bile duct or stones is suspected, an MRCP is indicated. With good sonographic evidence of common bile ducts stones or a positive MRCP an ERCP should be performed to accomplish endoscopic sphincterotomy with extraction of the biliary duct stones. This is followed in the next few days with laparoscopic removal of the gallbladder. The endoscopic approach to choledocholithiasis produces less morbidity, less possibility of long term common bile duct stenosis, and permits preop visualization of the biliary tree.  If the endoscopic stone extraction cannot be accomplished with ERCP, then open or laparoscopic common bile duct exploration is indicated.

Acute distension of the gallbladder in the absence of stones, bacteria, or congenital malformations is known as gallbladder hydrops. This condition has a vascular origin such as transient arteritis or ischemia. In older children hydrops will present with fever, nausea, vomiting, right upper quadrant mass and abdominal tenderness, while neonates and infants might show only a palpable mass. Gallbladder hydrops in neonates or infants is caused by systemic sepsis, while Kawasaki disease (mucocutaneous lymph node syndrome), scarlet fever, leptospirosis and trauma are the most common cause of hydrops in older children. The diagnosis of hydrops is established using abdominal ultrasound demonstrating normal biliary ducts and a distended gallbladder without calculi or congenital malformation. The treatment of hydrops is conservative. Management consists of systemic antibiotics and early enteral feeding to stimulate gallbladder function and decompression. Should pain and distension persists, open or percutaneous cholecystostomy may be helpful depending on the medical condition of the child.

Gallstone ileus is a very rare disorder characterized by mechanical obstruction of the gastrointestinal tract due to incipient impacted gallstones that passes through a bilio-enteric fistula. Impaction followed by obstruction can occur at the ileum, duodenum or stomach (Bouveret's syndrome). Diagnosis is usually delayed due to lack of specific signs of biliary disease. The classic triad of Rigler (small bowel obstruction, ectopic gallstones and air in the biliary tree) is visualized on abdominal plain films in only one-thirds of cases. Age ranges from 13 to 87 years with most cases seen in older patients. Most bilio-enteric fistulas are cholecystoduodenal type, with a few choledochoduodenal. Work-up includes ultrasound, upper gastrointestinal series with water soluble contrast medium and contrast enhanced computed tomography (CT). Preoperative diagnosis of gallstone ileus significantly increases by combining plain film and US findings. Management consists initially of simple enterotomy (enterolithotomy) which can be done laparoscopically assisted. This is followed by takedown of the bilioenteric fistula and cholecystectomy in a later stage procedure if the medical condition of the patient permits and he continues symptomatic. Some reports encourage enterolithotomy, repair of the fistula and cholecystectomy in one procedure. Other workers report that enterolithotomy alone is adequate treatment in the elderly, and subsequent cholecystectomy is not mandatory. Early diagnosis and treatment improve the outcome.

H. Idiopathic Perforation of Bile Ducts

Spontaneous perforation of the common bile duct is the second cause of surgical jaundice in infants. The perforation is generally identified at the junction of the cystic and common bile ducts. Most infants develop slowly progressive bilious ascites, jaundice, and clay-colored stools. Other patients develop an acute bile peritonitis.

Diagnosis is by ultrasound or HIDA scan showing extravasation. Paracentesis confirms the nature of the ascitic fluid. Management consist of intraoperative cholangiogram (to demonstrate area of leak), and adequate simple drainage of area. Periportal inflammation precludes vigorous surgical efforts that could be disastrous. Tube cholecystostomy placement help for post-op follow-up studies. The leak generally seals spontaneously during the ensuing 2-3 weeks. Prognosis is good with no long term biliary sequelae.

I. Splenic Cyst & Abscess, Splenoptosis, Spherocytosis and Asplenia

Splenic cysts in children are either considered true epidermal (congenital), pseudocysts

(post‑traumatic), or infectious (echinococcus) in etiology. They are rare, benign, solitary cysts often producing few symptoms. They may present as a palpable mass in the left side of the abdomen or during evaluation for another abdominal problem. Ultrasound (large unilocular sonolucent cyst) is the most important diagnostic method, and can be supplemented by CT‑Scan. The lining of the cyst is a flattened endothelium surrounded by fibrous tissue. This mesothelium can produce carcinoembryonic antigen (CEA). Indications for surgery are: (1) risk of complications (rupture, bleeding), (2) size greater than 5 cm., (3) infectious etiology, and a (4) symptomatic child (pain, mass or splenomegaly). Their management formerly total splenectomy has changed to: interventional sonography with fluid aspiration (catheter placement), or partial splenic decapsulation (cystectomy); the result of recognition of the physiologic importance (hematologic and immunologic) of the spleen, together with the development of radiological imaging and operative surgery. Long term follow‑up with radionuclide scans is recommended.

Splenic abscess is an uncommon event identified during the pediatric age. Nevertheless, is a potentially fatal disorder if not diagnosed and managed in a timely fashion. Children harboring a splenic abscess present with fever, leukocytosis and left upper quadrant abdominal pain. Simple chest films could be associated with a left pleural effusion or basal atelectasis. Most children with splenic abscess have an associated predisposing medical condition such as sickle cell disease, immune deficiency (HIV), leukemia, aplastic anemia, perforated bowel, typhoid fever, endocarditis, otitis media, appendicitis or trauma. Staphylococci, Salmonella and Escherichia coli are the most common etiologic agents in single abscess, while Candida species predominates in multiple splenic abscess. Many children are septic before the diagnosis is made. Blood cultures are seldom positive. Diagnosis is made with abdominal ultrasound or CT-Scan. Initial management incorporating the strategy of preserving the spleen consists of CT-guided percutaneous drainage and antibiotics. This combined approach is effective in two-thirds of cases. If the child does not improve, splenectomy follows. Children with immune deficiency and splenic abscess have rapid resolution of symptoms with immediate splenectomy. Some cases with splenic abscess will completely resolve with antibiotics alone.

Splenoptosis (Wandering spleen) is a rare congenital fusion anomaly of the dorsal mesogastrium of the spleen that results in failure and laxity of its normal attachment to the diaphragm, retroperitoneum and colon. Relatively more common in children than adults, and females outnumber males. The child presents with an asymptomatic mass (splenomegaly), mass and subacute gastrointestinal complaints or with acute abdominal symptoms. These are the result of torsion of the pedicle, ischemia and splenic sequestration. 50% of spleens are lost to acute ischemia from torsion. Other complications are: pancreatitis, hypersplenism and cyst formation. Lab tests are nonspecific, but may occasionally reveal evidence of hypersplenism or functional asplenia. Diagnosis needs a high index of suspicion, and is achieved with: Ultrasound, CT, and Scintigram. Management consists of splenectomy for frank splenic infarct, or splenopexy for viable organs. Splenopexy is achieved by creating an extraperitoneal pocket or wrapping the spleen in absorbable mesh and anchoring to the retroperitoneum (splenic nood).

Hereditary spherocytosis is a clinically heterogenous autosomal dominant red blood cell membrane disorder that causes anemia. The genetic defect results in deficiency of spectrin, the largest and most abundant structural protein of the erythrocyte membrane skeleton. The affected RBC loses its biconcave shape, strength and flexibility to the stress of circulation, becomes round and is trapped and destructs early in the spleen. Initial symptoms are those of pallor, jaundice and chronic anemia, followed by splenomegaly. Hemolytic crises are triggered by intercurrent infections. Pigment gallstones are common after the first decade of life. Labs' findings are those of many spherocytes in the peripheral smear, 8‑10 mg% hemoglobin, elevated reticulocyte count, increase erythropoiesis in the bone marrow, and negative Combsí test. Erythrocytes' shows increased osmotic fragility with autohemolysis in hypotonic solutions. Definitive therapy consists of splenectomy. This condition is the most common indication for elective splenectomy in children. The risk of overwhelming postsplenectomy sepsis makes it advisable to delay splenectomy until after six years of age unless the child becomes transfusion dependent. At the time of splenectomy, it is important to identify and remove accessory spleens. If gallstones are present, cholecystectomy should be done. A low content of spectrin and high percentage of microcyte has been used as determinants of early splenectomy as judge by the clinical severity of the disease process. Howell‑Jolly bodies in erythrocyte are identified after total splenectomy.

The absence of the spleen (asplenia) occurs after surgical removal, following chronic conditions or congenital. Trauma is the most common cause of removing the spleen in children and sickle cell disease is the most common cause of functional asplenia in children. Congenital absence of the spleen is usually associated with serious malformations, primarily cardiovascular and abdominal heterotaxia. The spleen contributes importantly to the normal and pathologic removal of blood cells from the circulation and to defense against infection with encapsulated bacteria. Asplenia increases the risk of fulminant bacteremia (post‑splenectomy sepsis) and mortality with these organisms. This risk is also increased by the underlying condition that caused the removal of the spleen, i.e., trauma, malignancy or hematologic disease. Several recommendations have been given when dealing with an asplenic individual. These are to vaccinate the child against pneumococcus (Pneumovax vaccine), hemophilus influenza type b and meningococcus. Regarding Pneumovax use revaccination after 3‑5 years is recommended for children with asplenia who are 10 years of age or younger and for older children and adults who were immunized at least five years before. Duration of vaccine‑induced antibodies is unknown but may be shorter than that in normal persons. Long‑term antimicrobial prophylaxis is also used. This carries the problem of compliance and for how long. Significant febrile episodes should be managed aggressively, and probably most important, the patient and family should be carefully educated about this complication (name tag). Most deaths from hyposplenia‑related septicemia are preventable.

Splenectomy impairs the immune response to bacterial infections. Such impaired immunologic functions include: formation of antibodies, deficiency of opsonization, lower IgM levels, deficiency in bacterial clearing and tuftsin deficient phagocytosis. Overwhelming post-splenectomy infection (OPSI) refers to a constellation of fast-developing symptoms (high fever, hypotension, rigor, bacteremia, and leucocytosis) that leads to death in patients that have undergo removal of the spleen. Mortality rates after OPSI is established are 50%. When obtainable, blood cultures grow encapsulated organisms (pneumococcus, meningococcus, hemophilus, etc.). The vulnerability of OPSI is greatest within the first two years after the splenectomy, and it persists throughout life. The clinical appearance of OPSI can go from a mild event to death from sepsis with pulmonary complications as the most common morbidity. OPSI is more commonly identified after spleen removal for Hodgkin and trauma. Immunization against pneumococcus, H. Influenza and meningococcus should be given to all children who undergo splenectomy since these are the most common organisms associated with OPSI. In the elective situation the vaccine should be given two weeks prior to removal of the spleen. In setting of trauma it should be given as soon as possible, Though several studies have found better functional antibody responses with delayed (14-day) vaccination in the setting of trauma we will continue to administer the vaccine as soon as possible until well-randomized trials are done.

It is estimated that 10% of the general population carries an accessory spleen. Accessory spleens are situated on the hilum of the spleen, splenic artery, pancreas, splenocolic ligament, greater omentum, mesenterium, adnexal region and scrotum. Trauma, torsion and hematologic hemolytic conditions affect an accessory spleen. A careful search should be made for accessory spleens, as they should be removed at the time of primary splenectomy to avoid a second operation later in life. Torsion with infarction of an accessory spleen must be considered as a rare cause of acute abdominal pain in childhood. Accessory splenic torsion causes acute diffuse or localized (left upper quadrant) abdominal pain sometimes indistinguishable from that caused by acute appendicitis or intussusception. Most affected children develop an intraperitoneal inflammatory mass.  Preoperative diagnostic imaging is unable to point to the diagnosis. Ultrasound shows a round, hypoechoic, solid mass. CT Scan demonstrates a low-density mass with peripheral enhancement after intravenous contrast medium. MRI can be helpful in the differential diagnosis of infarction by suggesting hemorrhagic necrosis on the T2-weighted images. Diagnosis is corroborated during laparoscopy or laparotomy. Accessory splenectomy is curative.

Removal of the spleen in children is considered necessary in some hemolytic diseases and trauma. Hemolytic disease where splenectomy is therapeutic includes idiopathic thrombocytopenic purpura, congenital spherocytosis and Sickle cell disease. Removal of the spleen with its attendant immunologic shortness can cause overwhelming sepsis. Overwhelming postsplenectomy infection is a fulminant process that carries a poor prognosis. The risk of serious infection is highest among young children, in immunologically compromised individuals and in the first few years after splenectomy. Current guidelines for children undergoing elective splenectomy include immunization for pneumococcus, meningococcus and hemophilus at least two weeks prior to the procedure. After emergency splenectomy the immunization protocol is the same, except that the amnestic response of the host is lower. Another guideline for splenectomized children includes the use of continuous antibiotic prophylaxis (penicillin) until the age of twelve years. Compliance with this antibiotic regimen is poor. It is recommended that parents be advised to bring the postsplenectomy child to the hospital anytime an illness or fever develops that might require an immediate loading dose of an appropriate antibiotic.

Splenic artery embolization as an alternative for splenectomy is a minimally invasive technique that has been utilized for the past 25 years. The procedure is done under local anesthesia, sedation or general anesthesia. Partial splenic artery embolization has been used in cases of thalassemia major to reduce transfusion requirements with variable results. Also in children with secondary hypersplenism or massive spleens due to portal hypertension, variceal bleeding (portal vein thrombosis, biliary atresia and biliary cirrhosis) or myelodysplastic disorders. The leukopenia and thrombocytopenia is corrected temporarily and variceal hemorrhage is ameliorated in most cases. Objective is to embolize at least two-third of the splenic circulation. After splenic artery embolization the child develops prolonged fever, pain in the left hypochondrium, leukocytosis and ileus. If the embolization causes total shutdown of the arterial circulation the child might develop a subcapsular hematoma with effusion, abscess formation or need for open splenectomy. Embolization allows for safe surgical splenectomy. Long term follow-up shows evidence of partial splenic regeneration. Partial splenic embolization is a useful method for reducing serum bilirubin concentrations in patients with hypersplenism following the Kasai procedure for biliary atresia, has also been found safe and effective minimally invasive treatment for patients with bleeding from a blocked distal splenorenal shunt, and as therapy for post-traumatic splenic artery pseudoaneurysm.

J. Adrenal Incidentaloma

With the advent of potent imaging studies during the eighties a group of adult patients was found with incidentally discovered adrenal masses, hence the term coined of adrenal Incidentaloma. At the time, masses below a size of three centimeters were observed with follow-up studies for spontaneous regression. Most cases resulted in benign non-functioning adenomas which disappeared with time. The situation in children is different. A mass identified in the adrenal gland is cause for concern. In infancy and childhood the most common adrenal mass is the neuroblastoma, a malignant neural crest tumor. Initial diagnosis of an adrenal mass in a child is made with Ultrasound, which is also used to document regression of uncomplicated neonatal adrenal hemorrhage. Further radiological assessment of an adrenal incidentaloma in a child should include CT-Scan and MRI. MRI can accurately distinguish adrenal adenomas from adenocarcinoma, pheochromocytoma and neuroblastomas. Endocrine tests evaluating pituitary-adrenal function (urinary excretion of 17-hydroxycorticosteroids, 17-ketosteroids and catecholamines, plasma concentrations of ACTH, cortisol, DHEAS, androstenedione and testosterone, dexamethasone suppression test and corticotrophin-releasing hormone stimulation test) should be part of the work-up. Should biochemical studies revealed no hormonal related disease (Cushing, hyperaldosteronism, pheochromocytoma, etc.) a histological diagnosis should be obtained by either CT-guided fine needle biopsy or surgical resection. In the event of no diagnosis, adrenal tumor resection should be done.

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