Paeds GI Flashcards
List features suggest pathological causes of jaundice.
Jaundice occurring in <24hrs of life
Prolonged jaundice >2 weeks
Conjugated bilirubinemia
Pale stools and dark urine (biliary obstruction)
Unwell/febrile/hemodynamically compromised baby
What are the risk factors for severe hyperbilirubinemia?
Prematurity
Early onset jaundice
Parent or sibling requiring phototherapy or exchange transfusion.
ABO or Rh incompatibility
Fhx of inherited hemolytic disorder
○ hereditary spherocytosis
○ glucose-6-phosphate dehydrogenase (G6PD) deficiency’
Isoimmune-mediated hemolysis
Sepsis
Cephalohematomas
Dehydration
What are the consequences of untreated severe hyperbilirubinemia?
Unconjugated bilirubin can cross blood brain barrier (lipid soluble unlike water soluble conjugated bilirubin)
Deposited in brain tissue, mainly basal ganglia and brain stem nuclei for oculomotor and auditory function causing:
Bilirubin induced neurological dysfunction (BIND) including the acute bilirubin encephalopathy (reversible if treated early enough) and irreversible chronic version kernicterus.
What are the clinical features of acute severe hyperbilirubinemia?
Jaundiced
Acute bilirubin encephalopathy
Early:
- Drowsy but rousable
- Mild to moderate hypotonia
- High pitched cry
Intermediate:
- Irritable and jittery with strong suck
OR
- Febrile and lethargic with poor suck
- Shrill cry
- Hypertonia with backwards arching od the neck (retrocollis) and trunk (opisthotonos) with stimulation
- Emergent exchange transfusion can prevent permanent bind
Advanced:
- Apnea
- Hypertonicity with persistent retrocollis and opisthotonos
- Seizures
- Coma
- Death due to respiratory failure or intractable seizures
What are the signs of kernicterus?
Becomes evident in the first year of life
Choreo-athertoid cerebreal pasly
Gaze paralysis (often upward)
Hearing loss
Enamel dysplasia of deciduous teeth
List the causes of early jaundice.
Sepsis
Haemolysis
- isoimmunisation (ABO and Rh alloantibodies
- RBC enzyme defects (G6PD, hereditary spherocystosis, alpha thalassemia)
- Haemorrhage
- Blood extravasation (bruising/birth trauma)
What is physiological jaundice and some of its causes?
- Usually first seen on day two of life
- Peaks on day three in term babies and days five to six in preterm babies
- Usually resolves in the first week to 10 days of life in a term baby or within three weeks in a preterm baby
Causes include:
- Increased bilirubin levels secondary to an increase in the volume and a
decrease in the life span of RBC and an immature liver with reduced enzyme activity
- Normal population variation in maturation of bile metabolism after birth
- More common in breastfed baby where there is inadequate milk intake
List the causes of conjugated and unconjugated jaundice.
Conjugated causes: (ALWAYS PATHOLOGICAL)
a. TORCH infections (Congenitally acquired infections including Toxoplasmosis, Other
(which isn’t very helpful but can include syphilis, varicella-zoster, parvovirus B19),
Rubella, CMV, and Herpes infections)
b. Sepsis / bacterial infection of any site
c. Viral infections
d. Drugs/toxins
e. Bile duct atresia/stenosis
f. Cystic fibrosis
- Unconjugated causes:
a. Physiologic jaundice (>50% of cases of jaundice!) Onset at 2-7 days of life.
b. Breast milk jaundice (2nd most common cause)
i. hormonally mediated or related to increased enterohepatic reabsorption of bilirubin. Typically presents after the first three to five days of life, peaking within two weeks after birth
c. Hemolysis:
i. ABO incompat.
ii. Cephalohematoma
iii. Breakdown diseases: spherocytosis, thalassemia, G6PD
d. Obstructive:
i. Meconium ileus
ii. Pyloric stenosis
e. Infectious
f. Metabolic
i. Congenital hypothyroidism
What are the indications for the investigation neonatal jaundice?
- Jaundice in first 24 hours of life
- Any elevated directed serum bilirubin level
- Rapidly rising total bilirubin level unexplained by history and physical
- Total serum bilirubin approaching exchange level or not responding to phototherapy
- Jaundice persisting beyond 3 weeks of age
- Sick appearing infant
What are the differential diagnoses of pediatric vomiting
Answer to be broken down into Mechanical, Inflammatory/infectious, Genitourinary, CNS, Metabolic and Other causes and then by age
What is the typical presentation from Hypertrophic pyloric stenosis?
- First few weeks of like (2-6 weeks but can be up to 20) as infants as born with normal pylorus with hypertrophies over time
Progressive gastric outlet obstruction causes
- Recurrent and progressively more forceful vomiting shortly after feeds
- Non bilious
- Infant remains hungry post feeds
- Later stages can exhibit visible waves of abdominal peristalsis in response to intense contractions against obstruction
- Palpable pylorus ‘olive’ in RUQ at lateral edge of rectus abdominis (settled infant lying flat and moving hand left to right)
- Hydrogen and chloride losses for gastric acid cause kidneys attempt to reabsorb hydrogen for potassium –> Hypochloremic Hypokalemic metabolic alkalosis
- May appear dehydrated, with poor weight gain or weight loss and FT
Not a true surgical emergency but may be fluid and electrolyte emergency.
Managed with pyloromyotomy.
What are the risk factors for hypertrophic pyloric stenosis?
- Male (up to 85%)
- First born
- Parental hx (especially maternal)
- Preterm
- Young maternal age
- Maternal smoking during prengnacy
- Post natal exposure to macrolides (maternal in first 2 weeks if breast feeding)
- Young maternal age
How is hypertrophic pyloric stenosis diagnosed?
Xray - String sign reflecting passage of contrast material through narrowed pyloric sphincter. In advanced stages on distended air-filled stomach seen with a modified double bubble sign or caterpillar sign
Ultrasound - Pylorus appears thickened (pyloric muscle thickness > 4 mm; pyloric diameter > 14 mm) and elongated (>19 mm)
What is malrotation with midgut volvulus?
Normally during embryological development the GI tract rotates around SMA with duodenum then fixed to retroperitoneum in LUQ at ligament of Trietz. Similarly, Caecum to retroperitoneum in RLQ.
They are held in place by Ladds bands
In malrotation there is no rotation and the duodenum and caecum are near each other with a short stalk of vasculature.
Not fixed anywhere in the abdomen so can easily rotate on itself.
Causes duodenal and SMA/SMV obstruction
Vascular compression results in ischemic of the bowel in 1-2 hours if not rapidly reversed.
What is the presentation of malrotation with midgut volvulus?
Typically, within the first month of life but majority within the first year
More commonly male
Sudden onset bilious vomit (bile initially yellow and turns green with time and oxidative exposure)
Hx of intermittent milder episodes
Abdominal distention if obstruction low enough in GI tract
May present very ill or in shock
Need urgent NG, surgical review, gas and bloods, IVF for hydration and imaging.
Piptaz or amp, gent and clinda/metro for septic children
How is malrotation with midgut volvulus diagnosed?
Diagnostic procedure of choice is the upper gastrointestinal series
Shows abnormal position of the duodenal C-loop and small bowel with a characteristic corkscrew appearance
Requires experienced technician or a radiologist
Plain AXR:
- air-fluid levels, dilated loops overlying the liver, and a paucity of small bowel gas distally
- “double bubble sign” may be present. The classic double bubble represents a dilated stomach and obstructed proximal duodenum and is seen with duodenal atresia and malrotation with midgut volvulus
Abdo US:
- abnormal positioning of the duodenal C-loop and inverted positioning of SMA/SMV (vein is abnormally positioned anteriorly or to the left of the artery)
- a “whirlpool sign” is described with the spiraled mesentery causing an echogenic twisting pattern.
- Place of US yet to be determined
How does NEC present and what are its Xray findings?
PRESENTATIONS
Typically, premature in the first few weeks of life. In full term it presents in first week of life
Feeding intolerance and vomiting (either bilious or non-bilious)
Can cause abdominal distention and palpable individual bowel loops.
In late or severe cases infants are extremely ill with hematemesis, hematochezia and shock.
AXR
Loss of symmetrical gas pattern
Variable degree of dilation
Pneumatosis intestinalis, gastralis and portal vein gas
Pneumoperitoneum
Intramural air is pathognomonic for NEC and present in 75% of all pts
What are the high risk features of an ingested foreign body? (FB, child and duration)
FB specific
- Button batteries lodged in esophagus (can erode mucosa in <2 hrs and cause severe burns and mediastinitis)
- Large object >6cm long +/- 2cm wide (entrapped in pylorus)
- Sharp object in esophagus
- Superabsorbent polymers (impaction)
- Magnet with metal or multiple magnets
- Toxic objects (lead)
Child specific
- Preexisting GI abnormalities
- Esoinophilic oesophagitis
- Neuromuscular disease
- Exam findings for signs of peritonism or obstruction
- Oropharynx FB (drooling, coughing, pain on swallowing, reduced oral intake)
Time specific
- Eosophageal FB for >24hrs or unknown time
- Button batteries that failed to pass from stomach after 48hrs
