Neonatology Flashcards
Investigation for biliary atresia*
> Blood
- FBC: anemia of chronic disease
- LFT
- Coagulation profile: decrease VitK dependent clotting factor -> PT increase
> Imaging
- Abdominal ultrasound: triangular cord sign, gallbladder ghost sign
- Hepatobiliary scintigraphy
> Definitive
- Percutaneous liver biopsy: bile duct proliferation, perilobular edema, fibrosis
- IntraOp cholangiogram
Describe Kasai procedure**
- Jejunum is anastomosed to patent ducts of portal hepatis with removal of gallbladder and bile duct
- The distal duodenum is anastomosed to the jejunal limb to create a Roux-en-Y configuration
Why Kasai best done before 2 months old
- Excessive backflow of bile will injure hepatocytes thus causing permanent hepatic injury
- Success rate for establishing good bile flow is much higher
Conjugated vs Unconjugated bilirubin
> Conjugated (with glucuronic acid)
- Soluble in water, insoluble in fat and alcohol
- Present in bile
- Not toxic to tissue
> Unconjugated
- Insoluble in water, soluble in fat and alcohol
- Not present in bile
- Toxic to tissue, can lead to kernicterus
Etiology of neonatal jaundice***
< 24 hours
- Unconjugated: ABO/ Rhesus incompatibility, G6PD/ Pyruvate kinase deficiency
- Conjugated: TORCHES
24 hours - 2 weeks
- Unconjugated: physiological, breastfeeding jaundice, hemorrhage, septicemia
- Conjugated: TORCHES
> 2 weeks (Prolonged)
- Unconjugated: congenital hypothyroidism, infection, breastmilk jaundice
- Conjugated: biliary atresia, TORCHES
Investigation for neonatal jaundice**
> Acertain underlying cause and extend of hemolysis (eg: severe, early onset)
- G6PD testing
- Mother’s and baby’s blood group
- Direct Coombs test - Rh incompatibility
- Full blood count + peripheral blood picture
- Reticulocyte count
- Septic workup (IF infection is suspected)
> TORCHES screening - antibody test
Ultrasound: choledochal cyst, gallstones
HIDA Scan (Hepatobiliary iminodiacetic acid)
What is HIDA scan
- Radioactive tracer is injected into a vein in arm, travels through bloodstream to liver, then travels with the bile into gallbladder and through bile duct into small intestine
Complication of Kasai procedure
- Cholangitis
- GI bleeding form varices
- Intestinal obstruction
Signs of neonatal sepsis*
- Hypo/ Hyperthermia
- Behavior change: lethargy, irritability, change in tone
- Skin: poor perfusion, pallor, jaundice, petechiae
- Feeding problem: poor feeding, vomiting, diarrhea
- Cardiovascular: tachycardia, hypotension
- Respiratory: tachypnea, cyanosis, respiratory distress
- Metabolic: hypo/ hyperglycemia, metabolic acidosis
Risk factor for acute bilirubin encephalopathy/ Kernicterus
- Hemolytic disease
- Sepsis
- Low gestational age
Complication of G6PD
- Severe neonatal hyperbilirubinemia -> Kernicterus
- Kidney failure
- Splenomegaly
- Cholelithiasis
Management of acute hemolysis in G6PD
- Inciting agent should be removed as soon as possible
- Aggressive hydration for acute intravascular hemolysis or transfusion for severe anemia -> prevent possible kidney damage from the precipitation
- Blood electrolyte should be checked and correction of abnormalities made
- Metabolic acidosis is usually observed but mostly resolved by transfusion support and fluid therapy
Advice for patient with G6PD
- Avoidance of unsafe drugs and chemicals (eg: Primaquine, chloroquine, hydroxychloroquine)
- Dietary restriction (eg: Fava bean, bitter melon)
- If have symptoms caused by medication taken, inform doctor or nurse and stop taking the medication
Neonatal jaundice can be detected clinically at which level
- Serum bilirubin rises above 5mg/dl
Causes of neonatal hypoglycemia*
> Inadequate glucose supply
- Inadequate glycogen store (eg: prematurity)
> Impaired glucose utilization
- Excessive insulin secretion
- Sepsis
Management of neonatal jaundice*
> Phototherapy
- For TB >20mg/dL, administered continuously until falls below this level
- Once reached, can be interrupted for feeding or parental holding
> Exchange transfusion
Indication:
- symptomatic infants with sign of bilirubin-induced neurologic dysfunction
- when intensive phototherapy fails to effectively reduce TB in infants
- TB >25mg/dL
- Isoimmune hemolysis - remove circulating antibodies and sensitized RBC
Complication of phototherapy
- Hyperthermia, hypovolemia
- “Bronze baby syndrome” - deposition of bronze-color photoisomers; usually resolve without sequelae within weeks
- Seizure
- Childhood cancer
- Skin manifestation - café-au-lait?
Complication of neonatal jaundice
- Liver cirrhosis
- Acute bilirubin encephalopathy
- Kernicterus (chronic)
Definition of failure to thrive
- Persistently below 3rd percentile
- Deceleration that crosses two major percentile
Pathophysiology of breast milk jaundice
- Human milk contains high concentrations of beta-glucuronidase, which catalyzes the hydrolysis of beta-D-glucuronic acid
- The loss of beta-D-glucuronic acid due to increased degradation is thought to promote an increase in intestinal absorption of unconjugated bilirubin
How to diagnosis neonatal sepsis*
- Elevated I/T ratio (>=0.2): immature to total neutrophil counts
- Total WBC count in neonate is physiological higher -> less sensitive?
Which medication can increase breast milk production
- Domperidone
- MOA: increases the level of hormone prolactin which is involve in breast milk production
Conditions associated with Down syndrome*
- Congenital cataract, squint and glaucoma
- Congenital heart defect (AVSD most common, VSD, PDA, ASD, TOF)
- Duodenal atresia, pyloric stenosis, tracheoesophageal fistula
- Hypothyroidism, hypogonadism
Causes of Down syndrome**
- Non-disjunction (95%): paired chromosome 21 failed to separate -> fertilization of gamete with 2 chr 21 -> trisomy 21
- Translocation (4%): result from unbalanced Robertsonian translocation where extra chr21 translocated onto chr14
- Mosaicism (1%)
Clinical features of Down syndrome*
> Facial
- Round face and short neck
- Flat occiput (brachycephaly and third fontanelle)
- Hypertelorism
- Bilateral upward slanting of eyes
- Flat nasal bridge
- Big, wrinkled tongue
> Upper and lower limbs
- Single palmar crease (simian crease)
- Clinodactyly
- Short, stubby fingers
- Hypotonia
- Sandal gap between big toe and second toe
Management of Down syndrome
- Careful examination to look for associated complications
- Investigations
§ Echocardiogram by 2 week (if clinical examination or ECG were abnormal) or 6 weeks
§ Chromosomal analysis
§ T4/ TSH at birth or by 1-2 weeks of life - Early intervention program should begin at diagnosis if health conditions permit
- Assess strength and needs of family
- Health surveillance and monitoring
Describe Kramer’s rule
- Blanching skin with slight finger pressure & noting underlying color of skin
- Area of body (mg/dL)
Hand and neck: 4-8
Upper trunk (above umbilicus): 5-12
Lower trunk (below umbilicus) 8-16
Arms and lower legs: 11-18
Palms & soles: >=18
Causes of FTT
> Inadequate intake
- Cleft lip, cleft platelet
- Inadequate frequency of feeding
> Inadequate absorption
- Inborn error of metabolism
- Pyloric stenosis
- GI atresia
- IBD/ Celiac disease (older children)
> Excessive loss
- Chronic diarrhea
- Parasitic infestation
> Increase demand for energy
- Chronic illness
- Thyroid disorder
- Malignancy
Features of common chromosomal defect
- Turner
- Klinefelter
- Edward
- Patau
> Turner (XO)
- Short stature, “shield” chest (widely spaced nipple, a short and webbed neck)
> Klinefelter (XXY)
- Neonatal: micropenis, hypospadias, or cryptorchidism
- Teenage: delayed puberty
- Men: small testes, androgen deficiency, infertility
> Edward (Trisomy 18)
- Small physical size, decreased muscle tone
- Low-set ears, overlapping fingers, clubfeet
- Heart/ lung abnormalities
> Patau (Trisomy 13)
- Small head, absent eyebrows, cleft lip/ platelet
- Dysplastic/ malformed ears
- Clenched hands and polydactyly
- Undescended testes
Clinical features for malnutritient
> Marasmus
- Inadequate energy intake including protein
- Low weight-for-height
- Reduced mid-upper arm circumference
> Kwashiorkor
- Protein deficiency with adequate energy intake
- Symmetric peripheral pitting edema
Prolonged jaundice in term vs preterm
> Term: >2 weeks
> Preterm: >3 weeks
Definition of direct and indirect bilirubin
- Direct = Conjugated
- Direct/ Total bilirubin ratio >15-20% -> conjugated hyperbilirubinemia
Cut off point for
- Low birth weight
- Very low birth weight
- Extremely low birth weight
- Small for gestational age
- LBW: <2500g
- VLBW: <1500g
- ELBW: <1000g
- SGA: <10 centile of birth weight for age
