Pediatric surgery

1. Pediatric surgery By Pr. Dr. Ayman Reda

2. Pediatric surgery Children are not small adults. They suffer from different disorders and their physical and psychological responses are different. Their capacity for adaptation is greater but they must endure any consequences of disease and its management for longer. In contrast to adults they rarely have comorbidity from degenerative diseases or lifestyle problems but they can suffer the unique consequences of congenital malformations. Children must be treated within the context of their families

3. ANATOMY AND PHYSIOLOGY Anatomical differences between adults and children are important in surgery. Infants and small children have a wider abdomen, a broader costal margin and a shallower pelvis. Thus, the edge of the liver is more easily palpable below the costal margin and the urinary bladder is an intra-abdominal organ. The ribs are more horizontal and respiratory function is more dependent on diaphragmatic movement. The umbilicus is relatively low lying. In the small child, transverse supraumbilical incisions are preferred to vertical midline ones for laparotomy. Abdominal scars grow with the child and may migrate – a gastrostomy sited in the epigastrium of the infant may end up as a scar over the costal margin.

4. Special features that must be considered in children when preparing for surgery ProblemAction Thermoregulation Warm fluids, warm theatre, insulate child HypoglycaemiaMaintain glucose level Clotting Give intramuscular vitamin K preoperatively to neonates Fluid and electrolyteAllow for higher sodium and fluid balance needs Less postoperativeCatabolismRelatively lower postoperative energy requirements Gastro-oesophageal refluxUse a nasogastric tube to prevent aspiration Atypical presentations of infectionHigh index of suspicion PsychologyTrained staff, day surgery for minor operations

5. Special features of surgical technique in children ■ Gentle tissue handling ■ Bipolar diathermy is preferred to unipolar during dissection ■ Abdominal incisions can be closed with delayed absorbable sutures( vic. ■ Bowel can be anastomosed with interrupted single-layer extramucosal sutures ■ Skin can be closed with absorbable subcuticular sutures

6. Esophageal Atresia and Tracheoesophageal Fistula • Esophageal atresia (EA) is a congenital interruption or discontinuity of the esophagus resulting in esophageal obstruction. • Tracheoesophageal fistula (TEF) is an abnormal communication (fistula) between the esophagus and trachea. EA may be present with or without a TEF. Alternatively, a TEF can occur without EA. • There is association of anomalies in patients with EA/TEF that must be considered under the acronym VACTERL (vertebral, anorectal, cardiac, tracheal, esophageal, renal,limb).

8. Diagnosis • The diagnosis of EA should be entertained in an infant with excessive salivation along with coughing or choking during the first oral feeding. A maternal history of polyhydramnios is often present. The inability to pass a nasogastric tube into the stomach of the neonate is a cardinal feature for the diagnosis of EA. Inability to pass a nasogastric tube in an infant with absent radiographic evidence for gastrointestinal gas is virtually diagnostic of an isolated EA without TEF • On the other hand, if gas is present in the gastrointestinal tract below the diaphragm, an associated TEF is confirmed. These simple rules provide the correct diagnosis in most cases. Occasionally, a small amount of isotonic contrast may be given by mouth to demonstrate the level of the proximal EA pouch and/or the presence of a TEF, but this is rarely necessary. In fact, the risk of aspiration with studies of this type is generally high

10. Management • The immediate care of an infant with EA/TEF includes IV fluid ,continuous suction of the proximal EA pouch and manipulation of the endotracheal tube distal to the TEF may minimize the leak and permit adequate ventilation. Further, placement of an occlusive balloon (Fogarty) catheter into the fistula via a bronchoscope may be useful. • Finally, urgent thoracotomy with direct ligation of the fistula after rapid preoperative preparation (exclude VACTERL)

11. Hypertrophic Pyloric Stenosis • It is one of the most common gastrointestinal disorders during early infancy, with an incidence of 1:3000 to 4000 live births. • This condition is most common between the ages of 2 and 8 weeks. In HPS, hypertrophy of the circular muscle of the pylorus results in constriction and obstruction of the gastric outlet. • Gastric outlet obstruction leads to nonbilious, projectile emesis, loss of hydrochloric acid with the development of hypochloremic, metabolic alkalosis, and ultimate dehydration.Visible gastric peristalsis may be seen as a wave of contraction from the left upper quadrant to the epigastrium. The infants usually feed vigorously between episodes of vomiting. Palpation of the pyloric tumor (also called the olive) in the epigastrium or right upper quadrant by a skilled examiner is pathognomonic. • Ultrasound is diagnostic .

12. Hypertrophic Pyloric Stenosis • The treatment of this condition is by surgical mechanical distraction of the pyloric ring (by a pyloromyotomy). • Prior to surgery,it is important that the infant is hydrated with intravenous fluids to establish a normal urine output. It is important that the underlying metabolic alkalosis is slowly corrected. • Postoperatively, infants are usually allowed to resume enteral feedings.

13. Duodenal Atresia • In contrast with more distal intestinal atresias, duodenal atresia (DA) is believed to occur as a result of failure of vacuolization of the duodenum from it solid cord stage. DA is associated with several conditions, including prematurity, Down syndrome, maternal polyhydramnios, malrotation, annular pancreas, and biliary atresia (BA). • The classic plain abdominal radiograph of DA is termed the double-bubble sign (air-filled stomach and duodenal bulb). • The treatment of DA is by surgical bypass of the duodenal obstruction by duodenoduodenostomy.

14. Jejunoileal Atresia • Intrauterine focal mesenteric vascular accident. The clinical presentation is typically dependent on the level of obstruction. • The treatment of JIA is to re-establish intestinal continuity.

15. Anomalies of Intestinal Rotation/Fixation • Midgut volvulus is a true surgical emergency since delay in operative correction is associated with a high risk of intestinal necrosis and subsequent death. The sudden appearance of bilious emesis in a newborn is the classic presentation.

16. Meconium Syndromes • The meconium syndromes of infancy represent a complex group of gastrointestinal conditions associated with CF( cystic fibrosis) • Meconium Plug is a frequent cause of neonatal intestinal obstruction and associated with multiple conditions including Hirschsprung’s disease, maternal diabetes, hypothyroidism, and CF. Typically, affected infants are often preterm and present with signs and symptoms of distal intestinal obstruction. Plain abdominal radiographs reveal multiple dilated loops of intestine. The diagnostic and therapeutic procedure of choice is a water-soluble contrast enema. This often results in the passage of a plug of meconium and relief of the obstruction. The operative management of simple meconium ileus is required when the obstruction cannot be relieved with contrast enema. • Complicated Meconium IleusMeconium ileus is considered complicated when perforation of the intestine has taken place.

17. Intussusception • Intussusception is the telescoping of one portion of the intestine into the other and is the most common cause of intestinal obstruction in early childhood. • In most pediatric intussusceptions, the cause is unknown, the location is at the ileocecal junction, and there is no identifiable pathologic lead point. Invariably, there is marked swelling of the lymphoid tissue within the region of the ileocecal valve. • The incidence of a pathologic lead point is up to 12% in most pediatric series and increases directly with age. The most common lead point for intussusception is a Meckel’s diverticulum; however, other causes must be considered including polyps, the appendix, intestinal neoplasm, submucosal hemorrhage associated with Henoch-Schönlein purpura, foreign body, ectopic pancreatic or gastric tissue, and intestinal duplication.

18. Clinically • Intussusception classically produces severe, cramping abdominal pain in an otherwise healthy child. The child often draws his or her legs up during the pain episodes and is usually quiet during the intervening periods. After some time, the child becomes lethargic. Vomiting is almost universal. Although frequent bowel movements may occur with the onset of pain, the progression of the obstruction results in bowel ischemia with passage of dark blood clots mixed with mucus, commonly referred to as “currant jelly” stool. An abdominal mass may be palpated. • In about half of cases, the diagnosis of intussusception can be suspected on plain abdominal radiographs. Suggestive radiographic abnormalities include the presence of a mass, sparse gas within the colon, or complete distal small bowel obstruction. In cases where there is a low index of suspicion for intussusception based on clinical findings, an abdominal ultrasound may be the initial diagnostic test. Ultrasonography can be diagnostic.

19. Management • When the clinical index of suspicion for intussusception is high, hydrostatic reduction by contrast agent or air enema is the diagnostic and therapeutic procedure of choice. • Contraindications to this study include the presence of peritonitis or hemodynamic instability. • Further, an intussusception that is located entirely within the small intestine is unlikely to be reached by enema and more likely to have an associated lead point. Hydrostatic reduction using barium has been the mainstay of therapy; however, more recently, the use of air enema has become more widespread. • Successful reduction is accomplished in more than 80% of cases and is confirmed by resolution of the mass, along with reflux of air into the proximal ileum. • To avoid radiation exposure altogether, intussusception reduction by saline enema under ultrasound surveillance may be employed. • Recurrence rates after hydrostatic reduction are about 11% and usually occur within the first 24 hours. Recurrence is usually managed by another attempt at hydrostatic reduction. A third recurrence is usually an indication for operative management.

20. Air enema reduction of an intussusception

21. Acute appendicitis Remember the following ■ Loose stools may be present ■ Tenderness and guarding in the right iliac fossa is characteristic ■ Exclude referred pain from right lower lobe pneumonia ■ Take special care in diagnosing appendicitis in the preschool child ■ Surgery is the treatment but only after fluid resuscitation and antibiotics

22. Hirschsprung’s Disease • Hirschsprung’s Disease is characterized pathologically by absent ganglion cells in the myenteric (Auerbach’s) and submucosal (Meissner’s) plexus. This neurogenic abnormality is associated with muscular spasm of the distal colon and internal anal sphincter resulting in a functional obstruction. Hence, the abnormal bowel is the contracted, distal segment, whereas the normal bowel is the proximal, dilated portion. • The area between the dilated and contracted segments is referred to as the transition zone. In this area, ganglion cells begin to appear, but in reduced numbers. • The aganglionosis always involves the distal rectum and extends proximally for variable distances. The rectosigmoid is affected in about 75% of cases, splenic flexure or transverse colon in 17%, and the entire colon with variable extension into the small bowel in 8%. • The risk for Hirschsprung’s disease is greater if there is a positive family history and in patients with Down syndrome.

23. Presentation and complication • In most, infants are symptomatic within the first 24 hours of life with progressive abdominal distention and bilious emesis. Failure to pass meconium in the first 24 hours is highly significant and a cardinal feature of this condition. In some infants, diarrhea may develop due to the presence of enterocolitis. • The diagnosis of Hirschsprung’s disease may also be overlooked for prolonged periods. In these cases, older children may present with a history of poor feeding, chronic abdominal distention, and a history of significant constipation. Since constipation is a frequent problem among normal children, referral for surgical biopsy to exclude Hirschsprung’s disease is relatively frequent. • Enterocolitis is the most common cause of death in patients with uncorrected Hirschsprung’s disease and may present with diarrhea alternating with periods of obstipation, abdominal distention, fevers, hematochezia, and peritonitis.

24. Investigation • The initial diagnostic step in a newborn with radiographic evidence for a distal bowel obstruction is a barium enema. Prior to this study, rectal examination and enemas should be avoided so as not to interfere with the identification of a transition zone. In a normal barium enema study, the rectum is wider than the sigmoid colon. In patients with Hirschsprung’s disease, spasm of the distal rectum usually results in a smaller caliber when compared with the more proximal sigmoid colon. Failure to completely evacuate the instilled contrast material after 24 hours would also be consistent with Hirschsprung’s disease and may provide additional diagnostic yield. • Anorectal manometry may also suggest the diagnosis of Hirschsprung’s disease. The classic finding is failure of the internal sphincter to relax when the rectum is distended with a balloon.This is more often useful in an older patient and is seldom used in neonates. • A rectal biopsyis the gold standard for the diagnosis of Hirschsprung’s disease. In the newborn period, this is done at the bedside with minimal morbidity using a special suction rectal biopsy instrument. It is important to obtain the sample at least 2 cm above the dentate line so as to avoid sampling the normal transition from ganglionated bowel to the paucity or absence of ganglia in the region of the internal sphincter.

26. Treatment • Traditionally, in mangement of intestinal obstruction caused by this a leveling procedure is done, followed by proximal diversion. • A definitive procedure is performed later and involves variations of pull through procedures among three main procedures. • In the Swensonprocedure, the aganglionic bowel is removed down to the level of the internal sphincters and a coloanal anastomosis is performed on the perineum. • In the Duhamel procedure, the aganglionic rectal stump is left in place and the ganglionated, normal colon is pulled behind this stump. A GIA stapler is then inserted through the anus with one arm within the normal, ganglionated bowel posteriorly and the other in the aganglionic rectum anteriorly. Firing of the stapler therefore results in formation of a neorectum that empties normally, due to the posterior patch of ganglionated bowel. • Finally, the Soave technique involves an endorectal mucosal dissection within the aganglionic distal rectum. The normally ganglionated colon is then pulled through the remnant muscular cuff and a coloanal anastomosis is performed. • More recently, the Soave procedure has been performed in the newborn period as a primary procedure and without an initial colostomy.

27. Anorectal malformations • The spectrum of anorectal malformations ranges from simple anal stenosis to the persistence of a cloaca. • By 6 weeks’ gestation, the urorectal septum moves caudally to divide the cloaca into the anterior urogenital sinus and posterior anorectal canal. • Failure of this septum to form results in a fistula between the bowel and urinary tract (in boys) or the vagina (in girls). • Complete or partial failure of the anal membrane to resorb results in an anal membrane or stenosis. • Breakdown of the cloacal membrane anywhere along its course results in the external anal opening being anterior to the external sphincter (i.e., anteriorly displaced anus). • An anatomic classification of anorectal anomalies is based on the level at which the blind-ending rectal pouch ends in relationship to the levator ani musculature . Historically, the level of the end of the rectal pouch was determined by obtaining a lateral pelvic radiograph (i.e., invertogram) after the infant is held upside down for several minutes to allow air to pass into the rectal pouch.

29. Clinical picture and investigation • Inspection of the perineum alone determines the pouch level in 80% of boys and 90% of girls. Clinically, if an anocutaneous fistula is seen anywhere on the perineal skin of a boy or external to the hymen of a girl, a low lesion can be assumed, which allows a primary perineal repair procedure to be performed, without the need for a stoma. • Most all other lesions are high or intermediate, and they require proximal diversion by a sigmoid colostomy. This is followed by a definitive repair procedure at a later date. If required, the level of the rectal pouch can be detailed more definitively by ultrasonography or MRI.

30. Abdominal Wall Defects • During normal development of the human embryo, the midgut herniates outward through the umbilical ring and continues to grow. By the 11th week of gestation, the midgut returns back into the abdominal cavity and undergoes normal rotation and fixation, along with closure of the umbilical ring. If the intestine fails to return, the infant is born with abdominal contents protruding directly through the umbilical ring and is termed an omphalocele . Most commonly, a sac is still covering the bowel, thus protecting it from the surrounding amniotic fluid. Occasionally, the sac may be torn at some point in utero, thus creating confusion with the other major type of abdominal wall defect termed gastroschisis. In contrast with omphalocele, the defect seen with gastroschisis is always on the right side of the umbilical ring with an intact umbilical cord, and there is never a sac covering the abdominal contents. The major morbidity and mortality with either anomaly are not as much with surgical repair of the abdominal defect as they are with the associated abnormalities. In the absence of other major anomalies, the long-term survival is excellent.

32. Treatment • The treatment of an omphalocele consists of a nasogastric or orogastric tube decompression for prevention of visceral distention due to swallowed air. An intravenous line should be secured for administration of fluids and broad-spectrum antibiotics. The sac should be covered with a sterile, moist dressing and the infant transported to a tertiary care pediatric surgery facility. • Prior to operative repair, the infant should be evaluated for potential chromosomal and developmental anomalies by a careful physical examination, plain chest radiograph, echocardiography if the physical examination suggests underlying congenital heart disease, and renal ultrasonography. Since the viscera are covered by a sac, operative repair of the defect may be delayed so as to allow thorough evaluation of the infant. • Several options exist for the surgical management of an omphalocele and are largely dictated by the size of the defect. In most cases, the contents within the sac are reduced back into the abdomen, the sac is excised with care to individually ligate the umbilical vessels, and the fascia and skin are closed. • Fascial closure may be facilitated by stretching the anterior abdominal wall as well as milking out the contents of the bowel proximally and distally.

33. In giant omphaloceles, the degree of visceroabdominal disproportion prevents primary closure and the operative management becomes more challenging. Construction of a Silastic silo allows for gradual reduction of the viscera into the abdominal cavity over several days. Monitoring of intraabdominal pressure during reduction may prevent the development of an abdominal compartment syndrome. Once the abdominal contents are returned to the abdomen, the infant is taken back to the operating room for formal fascia and/or skin closure. • Occasionally, closure of the fascia may be impossible. In these cases, the skin is closed and a large hernia is accepted. This is repaired after 1 or 2 years. When the skin cannot be closed over the defect, several options exist, including the topical application of an antimicrobial solution to the outside of the sac such as silver nitrate or silver sulfadiazine. Over time, this results in granulation tissue and subsequent epithelialization of the sac. A repair of the large hernia is then performed a few years after this.

34. Inguinal Hernia in the pediatric age group • Repair of an inguinal hernia (IH) represents one of the most frequent surgical procedures performed in the pediatric age group. Virtually all IH in children are indirect and congenital in origin. • Most IH present as a bulge in the region of the external ring extending downward for varying distances to the scrotum or labia. Often, the hernia is detected by a pediatrician during a routine physical examination or observed by the parents. Inguinal pain may also be a presenting complaint. • Incarceration and possible strangulation are the most feared consequences of IH and occur more frequently in premature infants. Because of the risk for these complications, all IH in children should be repaired.

35. IH repair in premature infants • The timing for IH repair in premature infants is controversial. Early repair may be associated with a higher risk for injury to the cord structures, greater recurrence rate, and anesthetic-related apnea. These factors must be weighed against the higher risk for incarceration and strangulation, the potential for losing the patient during follow-up, and the development of a larger IH with loss of domain in the abdominal cavity. Taking these factors into account, most pediatric surgeons perform herniorrhaphy before the neonate is discharged to home from the nursery. • If the infant has already been discharged home, most pediatric surgeons wait until the infant is older than 60 weeks postconception (gestational age + postnatal age). After this age, the risk for postoperative apnea is diminished.

36. In patients with incarcerated IH containing bowel, attempts should be made to reduce the hernia, unless there is clinical evidence of peritonitis. • This may require intravenous sedation and careful monitoring. • If the reduction is successful, the child is admitted and observed for 24 to 48 hours. The IH repair should be done after the period of observation to allow for tissue edema to subside. • On the other hand, if the IH cannot be reduced, the child should be promptly taken to the operating room for inguinal exploration.

37. Biliary Atresia BA • BA is characterized by progressive (not static) obliteration of the extrahepatic and intrahepatic bile ducts. The cause is presently unknown. Patients who are not offered surgical treatment uniformly develop biliarycirrhosis, portal hypertension, and death by 2 years of age. • Pathologically, the biliary tracts contain inflammatory and fibrous cells surrounding minuscule ducts that are probably remnants of the original ductal system. Bile duct proliferation, severe cholestasis with plugging, and inflammatory cell infiltrate are the pathologic hallmarks of this disease. This histology is usually distinct from the giant cell transformation and hepatocellular necrosis that are characteristic of neonatal hepatitis, the other major cause of direct hyperbilirubinemia in the newborn. • A serum direct bilirubin level higher than 2.0 mg/dL or greater than 15% of the total bilirubin level defines cholestasisand is distinctly abnormal, and further evaluation is mandatory. Delay in diagnosis of BA is associated with a worse prognosis. Thus, the initial opportunity for success in the management of this disease relies on the early recognition of abnormal direct hyperbilirubinemia.

38. Investigation • In addition to a careful history and physical examination, blood and urine should be obtained for bacterial and viral cultures, reducing substances in the urine to rule out galactosemia, serum IgM titers for syphilis, cytomegalovirus, herpes, and hepatitis B, serum α1 -antitrypsin level and phenotype, serum thyroxine level, and a sweat chloride test done to exclude CF • Ultrasonography of the liver and gallbladder is important in the evaluation of the infant with cholestasis. In BA, the gallbladder is typically shrunken or absent, and the extrahepatic bile ducts cannot be visualized. • The next diagnostic step is to perform a percutaneous liver biopsy if the hepatic synthetic function is normal. This is well tolerated under local anesthesia, and the diagnostic accuracy is in the range of 90%.

39. Treatment • If the needle biopsy and/or the abdominal ultrasound are consistent with BA, exploratory laparotomy (laparoscopy) is then performed expeditiously. • The initial goal at surgery is to confirm the diagnosis. This requires the demonstration of the fibrotic biliary remnant and definition of absent proximal and distal bile duct patency by cholecystocholangiography. • The classic technique for correction of BA is the Kasai hepatoportoenterostomy. In this procedure, the distal bile duct is transected and dissected proximally up to the level of the liver capsule, whereby it is excised, along with the gallbladder remnant . A Roux-en-Yhepaticojejunostomy is then constructed by anastomosis of the jejunal Roux-limb to the fibrous plate above the portal vein.

40. Choledochal Cyst • A cystic enlargement of the common bile duct is referred to as a choledochal cyst. • Types Type I cysts represent 80% to 90% of cases and are simply cystic dilations of the common bile duct. Type II cysts are represented as a diverticulum arising from the common bile duct. Type III cysts are also referred to as choledochoceles and are isolated to the intrapancreatic portion of the common bile duct and frequently involve the ampulla. Type IV cysts are second in frequency and represent dilation of both intrahepatic and extrahepatic bile ducts. In type V cysts, only the intrahepatic ducts are dilated. • The pathophysiology of choledochal cysts remains poorly understood.

41. Clinical picture and investigation • Although choledochal cysts can produce symptoms in any age group, most become clinically evident within the 1st decade of life. The triad of a right upper quadrant mass, abdominal pain, and jaundice is highly suggestive of the diagnosis. • In some patients, pancreatitis may bepresent. • In older children and adults, the presentation may be more insidious and include choledocholithiasis, cholangitis, and cirrhosis with progression to portal hypertension. • Malignant degeneration is also found in up to 16% of adults with choledochal cysts. • In addition to routine measurement of serum bilirubin, alkaline phosphatase, and amylase levels, the most useful diagnostic test for choledochal cysts is ultrasonography. Once dilation of the extrahepatic biliary ducts is demonstrated, no further testing is usually necessary in children. • Although seldom necessary, preoperative endoscopic retrograde cholecystopancreatography may provide additional information regarding the pancreaticobiliary ductal anatomy to guide intraoperative decision making.

42. Treatment • Total cyst excision with Roux-en-Y hepaticojejunostomy is the definitive procedure for management of types I and II choledochal cysts. • In cases whereby there is significant inflammation, it may be impossible to safely dissect the entire cyst way from the anterior surface of the portal vein. In these circumstances, the internal lining of the cyst can be excised, leaving the external portion of the cyst wall intact. • Type III cysts are typically approached by opening the duodenum, resecting the cyst wall with care to reconstruct and marsupialize the remnant pancreaticobiliary ducts to the duodenal mucosa. • In type IV cysts, the bile duct excision is coupled with a lateral hilar dissection to perform a jejunal anastomosis to the lowermost intrahepatic cysts. • If the intrahepatic cysts are confined to a single lobe or segment, hepatic resection may be indicated. • The treatment of type V cysts involving both lobes is usually palliative with transhepatic or U tubes until liver transplantation can be performed. • The postoperative outcomes following excision of choledochal cysts are excellent

43. Neuroblastoma • Neuroblastoma (NBL), the most common abdominal malignancy in children. • These tumors are of neural crest origin and, as a result, may arise anywhere along the sympathetic ganglia or within the adrenal medulla. • Although these tumors may occur at any site from the brain to the pelvis, 75% originate within the abdomen or pelvis, and half of these occur within the adrenal medulla. Twenty percent of NBLs originate within the posterior mediastinum, and 5% are within the neck. • The median age at diagnosis is 2 years. • Approximately 25% of patients present with a solitary mass that may be cured by surgical therapy, whereas most present with extensive locoregional or metastatic disease.

44. Clinical picture • The presenting symptoms of NBL are dependent on several factors, including the site of the primary tumor, the presence of metastatic disease, the age of the patient, as well as the metabolic activity of the tumor. • The most common presentation is a fixed, lobular mass extending from the flank toward the midline of the abdomen. Although the abdominal mass may be noted in an otherwise asymptomatic child, patients may complain of abdominal pain,distention, weight loss, or anorexia. Bowel or bladder dysfunction may arise from direct compression of these structures by the tumor. • Cervical tumors may be discovered as a palpable or visible mass or be associated with stridor or dysphagia. • Posterior mediastinal masses are usually detected by plain chest radiographs in a child with Horner’s syndrome, dyspnea, or pneumonia. • Further, the tumor may extend into the neural foramina and cause symptoms of spinal cord compression. • Marrow replacement by tumor may result in anemia and weakness. • Numerous paraneoplastic syndromes can occur in conjunction with NBL. Cerebellar ataxia, involuntary movements, and nystagmus are the hallmark of the “dancing eyes and feet” syndrome. Excess secretion of vasoactive intestinal polypeptide may stimulate an intractable watery diarrhea. Hypertension may be significant, owing to excessive catecholamine production by the tumor.

45. Management • A spot urine should be tested for the catecholamine metabolites homovanillic and vanillylmandelic acid. • A serum lactate dehydrogenase level higher than 1500 IU/mL, serum ferritin level higher than 142 ng/mL, and neuron-specific enolase levels higher than 100 ng/mL correlate with advanced disease and reduced survival. • CT and/or MRI are the preferred modalities for characterizing the location and extent of the NBL. This tumor frequently infiltrates through vascular structures . As such, many tumors that cross the midline are generally not resectable. • A CT scan of the chest should be done to exclude pulmonary metastasis, and a bone scan should be done to identify potential bone metastasis. • In addition, radiolabeled metaiodobenzyl guanidine (MIBG) is one of the single best studies to document the presence of metastatic disease. • Finally, a bone marrow aspirate . • Current therapy for NBL is multimodal: incorporating surgery, chemotherapy, radiation, and occasionally immunotherapy.

46. Teratoma • Teratomas are tumors that contain elements derived from more than one of the three embryonic germ layers. In addition, teratomas must contain tissue that is foreign to the anatomic site in which they occur. Teratomas can occur anywhere in the body and present as cystic, solid, or mixed lesions. When they occur during infancy and early childhood, they are most commonly extragonadal. In contrast, in older children teratomas most frequently involve the gonads. • Teratomas occur most frequently in the neonatal period and the sacrococcygeal region is the most common site. Sacrococcygeal teratoma (SCT) is four times more common in females and is most often an obvious external presacral mass.

47. Diaphragmatic Hernia, Congenital • 80% are left-sided • Symptoms and signs include dyspnea, chest retractions, decreased breath sounds on affected side • Prenatal ultrasound is accurate in 40–90% of cases, showing herniation of abdominal contents in thorax ,chest film, arterial blood gas measurements, echocardiogram; ultrasound for neural tube defects. • The posterolateral location of this hernia is known as Bochdalek’s hernia and distinguished from the congenital hernia of the anteromedial, retrosternal • diaphragm, which is known as Morgagni’s hernia. • Primary repair or mesh repair once respiratory status has been optimized

48. Hypospadias Failure of complete urethral tubularisation in the male fetus results in hypospadias, a common congenital anomaly affecting about one in every 200–300 boys. In most cases the urethra opens just proximal to the glans penis but in severe cases the meatus may be on the penile shaft or in the perineum. The dorsal foreskin is hooded and there is a variable degree of chordee (a ventral curvature of the penis most apparent on erection) . Glanular hypospadias may be a solely cosmetic concern but more proximal varieties interfere with micturition and erection. In severe forms of hypospadias, additional genitourinary anomalies and intersex disorders should be excluded. Surgical correction of distal hypospadias is frequently undertaken before 2 years of age, often as a single-stage operation. Proximal varieties may require complex staged procedures. Surgery aims to achieve a terminal urethral meatus so that the boy can stand to micturate with a normal stream, a straight erection and a penis that looks normal. Ritual circumcision must be avoided in infants with hypospadias because the foreskin is often required for later reconstructive surgery.