Aquifer Pediatrics: Case 15 - Two siblings with vomiting

Differential Diagnosis for Recurrent Emesis in the Infant

Gastroesophageal reflux Milk Protein Allergy Viral Gastroenteritis Malrotation +/- volvulus Inborn error of metabolism Pyloric stenosis Intussusception CNS disease UTI

Intussusception

Infants with intussusception typically have bilious emesis and crampy or severe intermittent abdominal pain. The classic "currant jelly" stool of intussusception occurs late and may be mis-identified in the history as diarrhea. The abdominal exam in children with intussusception often shows the presence of a "sausage-like" mass due to the telescoped bowel.

malrotation +/- volvulus

Malrotation may be present without volvulus (twisting of the intestine on itself) and by itself it does not necessarily cause symptoms. However, malrotation may result in volvulus, with acute onset vomiting and other signs of bowel obstruction. Bilious emesis is common with intestinal volvulus. Blood may be seen in the stool but not typically in the vomitus. Bowel ischemia from volvulus can cause significant abdominal pain. Infants with malrotation and volvulus may present with shock, which may initially be difficult to distinguish from dehydration.

Milk Protein Allergy

Milk protein allergy may present with vomiting immediately after eating but more typically will present with a rash or loose stools; it does not typically cause dehydration.

Dx work-up of possible pyloric stenosis

Pyloric ultrasound In experienced hands, a pyloric ultrasound is the study of choice to confirm pyloric hypertrophy. Upper GI contrast study If ultrasound is unavailable, an upper GI contrast study will demonstrate a very narrow pyloric channel (the "string sign"), indentation of the hypertrophied pylorus on the antrum of the stomach, and delayed gastric emptying. If there is significant concern for malrotation or volvulus, the upper GI study should include imaging of contrast passing through the small intestine as well. (The absence of bilious emesis suggests no obstruction beyond the pylorus.) Electrolytes Pyloric stenosis is typically associated with electrolyte abnormalities because of loss of stomach fluid and inadequate fluid intake. These abnormalities include hypochloremia, hypokalemia, and alkalosis. (There may also be some metabolic acidosis related to lactic acidosis from dehydration, but the primary abnormality is typically metabolic alkalosis.) Correction of metabolic status is necessary before corrective surgery can be performed.

GERD

Regurgitation/spitting up may be difficult to distinguish from true vomiting. Infants who reflux with overfeeding may sometimes have forceful vomiting. Severe esophagitis may result in blood-streaked emesis. Pain from reflux or esophagitis may lead to feeding aversion when gastroesophageal reflux is severe. An infant who is dehydrated due to severe GE reflux should also have significant failure to thrive.

You are seeing a 1-month-old infant who is < 3rd percentile for weight. He is breastfed every 2 hours and latches on well. However, he has frequent non-bilious episodes of vomiting that have been increasing over the past week despite his mother taking "reflux precautions." He does not have mucus or blood in his stool. Physical exam reveals a small, olive-sized mass in his abdomen. What is the most likely diagnosis? The best option is indicated below. Your selections are indicated by the shaded boxes. A. Cleft palate B. Pyloric stenosis C. Cystic fibrosis D. Non-organic failure to thrive E. Munchausen syndrome by proxy

B. Choice B is correct because the history of frequent vomiting, poor weight gain, and the finding of an abdominal mass are consistent with pyloric stenosis. Children with pyloric stenosis often present at 3 weeks of age.

What is your immediate management plan (acute dehydration of 8wk infant)? Choose the single best answer. The best option is indicated below. Your selections are indicated by the shaded boxes. A. Continue ORS, using smaller volumes than originally given by the ED staff B. Order electrolytes to assess the serum sodium prior to giving IV fluids C. Give an IV bolus of normal saline (20mL/kg) 100mL as fast as possible D. Begin maintenance fluids with D5 1/4NS at 22 mL/hour E. Await the results of the surgical consult before making any management decisions

The correct answer is C. As you learned from the handout on fluid management from Dr. Whitman, IV bolus therapy (C) is the primary therapy for severe dehydration, using 20 mL/kg aliquots of normal saline, lactated Ringer's, or balanced electrolyte solution such as Plasmalyte or Normosol.

Dr. Whitman agrees with you that Caleb is mildly to moderately dehydrated. She asks how you would like to provide rehydration. Choose the single best answer. A. Send him home with instructions to begin oral rehydration with a commercially prepared solution B. Send him home with instructions to encourage fluids including diluted formula and sports beverages C. Begin oral rehydration with a commercially prepared solution while monitoring Caleb in the pediatric clinic D. Begin IV fluids in the pediatric clinic E. Arrange for hospital admission for IV fluids

The correct answer is C. In Caleb's case, it is reasonable to begin ORT under supervision (C), to confirm that he will drink the glucose-electrolyte solution and that he improves appropriately.

Fluid Therapy for Severe Dehydration

The primary recommended mode of therapy for severe dehydration is to provide volume restoration via IV bolus therapy with an isotonic saline solution. Repeated 10-20 mL /kg boluses of normal saline are given (up to three times, reassessing after each bolus) until the patient has improved to only mild dehydration or normal fluid status. Normal saline is the preferred fluid choice in pyloric stenosis because of its high chloride content - and because it does not contain lactate, a base which could worsen the alkalosis. Rehydration can then be completed either orally (if vomiting has resolved) or with ongoing IV fluids.

Calculating Rehydration Volume in Mild-Moderate Dehydration

The recommended fluid replacement volume for mild-moderate dehydration is 50-100 mL/kg, to be replaced over 2-4 hours. Example: Patient's weight = approx. 18 kg 50 mL/kg = 900 mL 100 mL/kg = 1800 mL Total replacement volume should be 900-1800 mL (30-60 oz.), to be given over 2-4 hours.

UTI

UTI is an important extraintestinal cause of vomiting in children. In infants, symptoms of UTI are non-specific and may include fever, poor feeding and vomiting, leading to dehydration if not identified and treated. Infants with a UTI are unlikely to have watery diarrhea but loose stools may be seen in the setting of significant infection.

Inborn Error of Metabolism

Although uncommon, metabolic disorders should be considered, particularly in infants with recurrent emesis. Symptoms may be triggered by intercurrent illness such as gastroenteritis or infections. Infants with inborn errors may present with diminished oral intake for a variety of reasons, including lethargy and irritability. Metabolic disorders may also present with shock, which may be difficult to distinguish from severe dehydration.

Pyloric Stenosis

An escalating pattern of forceful (projectile), non-bilious vomiting is a hallmark of pyloric stenosis. Bilious emesis is not typical because the obstruction is above the ligament of Treitz. Infants with pyloric stenosis can have rapid dehydration due to inadequate fluid absorption, but they typically have a vigorous appetite until late in the clinical course. Infants with pyloric stenosis often present with mild-moderate dehydration due to persistent vomiting. The presence of hypochloremic, hypokalemic metabolic alkalosis with dehydration is another hallmark of pyloric stenosis. Bloody emesis is sometimes seen in pyloric stenosis and other causes of forceful emesis due to the development of Mallory-Weiss tears in the esophagus. Infants with pyloric stenosis may demonstrate a visible peristaltic wave (particularly just after eating). A palpable "olive" (the hypertrophic pyloric muscle) in the epigastric region very strongly suggests the diagnosis but is often difficult to appreciate.

Rashid is a 5-week-old infant who presents to clinic with 4 days of repeated, forceful, non-bilious, non-bloody vomiting without diarrhea. He has 8 to 9 episodes of vomiting per day immediately following breastfeeding. The episodes started 2 weeks after the entire family suffered from severe viral gastroenteritis. His birth history is uncomplicated (full term, NSVD, unremarkable 30-week ultrasound) and birth weight was 3.6 kg (50th percentile). On exam, his vitals are: T 36.7°C, HR 185, BP 85/45, RR 36, Wt 4.1 kg (25th percentile). On exam, his eyes are moderately sunken without production of tears, his lips are cracked, and his throat is without erythema. His capillary refill is ~3 seconds, and his pulse is thready. What is your first step in management? The best option is indicated below. Your selections are indicated by the shaded boxes. A. Close observation in the office for 6 hours and encourage PO intake until vitals normalize. B. Intravenous lactated Ringer's solution of 20mL/kg boluses until baseline clinical status is achieved, then 100 mL/kg oral rehydration solutions over next 4 hours. C. Intravenous 20 mL/kg boluses of ¼ normal saline solution until baseline clinical status is achieved, then closely monitor vitals for 6 hours while encouraging PO formula intake. D. Observe for 6 hours with normal PO intake and administer 60-120 mL of oral rehydration solution for every episode of vomiting. E. Administer 75 mL/kg of oral rehydration solution over 3-4 hours and 60-120 mL of oral rehydration solution for every episode of vomiting.

B. Lactated Ringer's solution or normal saline in 20 mL/kg boluses until urine output is established and mental status improves, then 100 mL/kg oral rehydration solutions over next 4 hours. This follows current CDC guidelines for treating a severely dehydrated child. Intravenous hydration with 5% dextrose ½ normal saline at twice maintenance fluid rates may be substituted for the oral rehydration solution if the child is not tolerating PO intake. To replace ongoing losses, the CDC recommends 60-120mL of oral rehydration solution per diarrheal/emetic episode (through a nasogastric tube, if necessary).

A 6-month-old infant comes to clinic because of several weeks of vomiting after large feedings. The vomiting has become blood-streaked, which is when the mom became concerned and brought him in. The baby's PO intake has been down and he has been losing weight. Abdominal exam is normal, with no masses palpated. What is the most likely diagnosis? The best option is indicated below. Your selections are indicated by the shaded boxes. A. Pyloric stenosis B. Gastroenteritis C. GERD D. Volvulus E. Intussusception

C. Choice C is correct because regurgitation/spitting up may be difficult to distinguish from true vomiting. Infants who reflux with overfeeding may sometimes have forceful vomiting. Severe esophagitis may result in blood-streaked emesis. Pain from reflux or esophagitis may lead to feeding aversion when gastroesophageal reflux is severe.

Which of the following defines the best fluid management plan for Ben (hypokalemic, hypochloremic metabolic alkalosis)? Choose the single best answer. The best option is indicated below. Your selections are indicated by the shaded boxes. A. Complete IV hydration to match an estimated fluid deficit of 10%, then switch to ORS B. Begin IV fluids including ammonium chloride for correction of alkalosis C. Administer repeated IV normal saline boluses (20 mL/kg) until there is significant clinical improvement, then continue IV fluids (dextrose, sodium chloride and potassium) until after surgery D. Bolus with hypertonic (3%) sodium chloride to effect rapid correction of hypochloremia E. Defer fluid management to the Pediatrics Surgery team

C; Ben should not receive oral fluids until after the pyloric stenosis has been surgically corrected, so he will need IV fluids designed to provide energy needs (dextrose) and to continue correction of his metabolic abnormalities (sodium chloride and potassium chloride) as well as his dehydration.

CNS Disease

CNS diseases causing increased intracranial pressure -such as hydrocephalus, intracranial neoplasm, and trauma (accidental or non-accidental)-must be considered in vomiting children, especially in the absence of fever and diarrhea.

Johnny is a 25-month-old male who presents to the ED with a 2-day history of vomiting and diarrhea. Dad relays a history of abrupt onset of vomiting that started yesterday around 1 pm. Johnny has had 6 episodes of emesis since yesterday and 3 episodes of diarrhea. The emesis is non-bilious and the diarrhea is described as watery with specks of blood throughout the diarrhea. There are no sick contacts in the home. Vital signs: T 37.1, P 102, R 20, BP 90/60. Physical examination is normal and Johnny has still been tolerating some PO feeds without instant vomiting. What is the most immediate intervention for this patient? The best option is indicated below. Your selections are indicated by the shaded boxes. A. IV bolus with D5W B. IV bolus with 0.9% saline C. CT scan and surgical consult D. random glucose test E. no immediate intervention is necessary

E. At this point the patient is most likely suffering from a case of viral gastroenteritis. Because he is still tolerating some PO feeds, has no obvious signs of dehydration, and has normal vital signs, there is no need for aggressive IV fluid administration or diagnostic work up. Strict return precautions should be given and it should be advised that Johnny maintains fluids as much as possible.

A 15-month-old boy presents to the ED in January with a 3-day history of diarrhea. His current weight is 11 kg. He was born at 39 weeks, without any perinatal complications. There is no significant history of travel, sick contacts, or recent changes in diet. The mother notes that he has had only 2 diaper changes over the last day. Physical exam is remarkable for an irritable but consolable infant with tachycardia and normal blood pressure. He is crying without tears and his mucous membranes are dry. His abdominal exam is benign. There is no tenting, and capillary refill is 2 seconds. He is diagnosed with gastroenteritis and started on rehydration therapy. Which of the following statements is true? The best option is indicated below. Your selections are indicated by the shaded boxes. A. The patient is mildly dehydrated and should be managed with oral rehydration (Pedialyte). B. The patient is moderately dehydrated and should be managed with oral rehydration (Gatorade). C. The patient should be rehydrated with clear liquids and then transitioned to a lactose-free diet until his diarrhea resolves. D. The patient is moderately dehydrated and should be bolused with 220 ccs of D5 ½ normal saline for emergency phase correction, to ensure hemodynamic stability. E. ) The work-up for infectious diarrhea for this patient should include a Wright's stain for fecal WBCs, a stool Rotazyme, and a stool sample for culture and sensitivity.

E. In addition to correcting this patient's hydration status, a work-up for the infectious causes of this patient's diarrhea might include a stool Wright's stain for fecal WBCs (which would suggest a bacterial cause if this is infectious diarrhea), a Rotazyme test (given the high incidence of rotavirus in the winter months), and a stool sample for culture and sensitivity. Additional studies might include stool guaiac (for occult blood) and a check for stool C. diff toxin

Viral Gastroenteritis

Early in the course of the infection there may be isolated vomiting, but large watery stools are the hallmark of infectious gastroenteritis. Dehydration due to fluid losses often accompanies gastroenteritis. Bilious emesis is not typically seen with gastroenteritis or a GI tract obstruction above the ligament of Treitz, but small amounts of bile may be seen with repetitive vomiting. "Enteritis" is not truly present if diarrhea is not present.

List items in your broad working differential diagnosis for Caleb's symptoms (diarrhea > vomiting)

Viral gastroenteritis Bacterial gastroenteritis Surgical process (e.g., small bowel obstruction, appendicitis) Inflammatory bowel disease Viral gastroenteritis is a common diagnosis in children, typically presenting with both vomiting and diarrhea. Bacterial gastroenteritis classically presents with bloody or profuse diarrhea Small bowel obstruction would most likely have vomiting and not diarrhea. Emesis may be bilious if the obstruction is below the Ampulla of Vater, as is often the case in volvulus. Appendicitis typically presents with abdominal pain as the primary feature, but patients may also have vomiting and diarrhea, and often have fever. Inflammatory bowel disease would present with chronic diarrhea, often bloody, and usually not with vomiting Regardless of the suspected diagnosis, it is always essential to evaluate for dehydration in a child with vomiting and/or diarrhea.