Review – Kaplan Pediatrics: Newborn Specific Disorders

Endocrine Disorders

Infants of diabetic mothers

fetal hyperinsulinemia
increase in size of all organs except the brain
hypoglycemia, hypocalcemia, hypomagnesemia
large for gestational age and plethoric (ruddy)
Cardiomegaly—asymmetric septal hypertrophy.
Polycythemia (and hyperviscosity) → hyperbilirubinemia → jaundice
Renal vein thrombosis (flank mass, hematuria, and thrombocytopenia) from polycythemia
Increased incidence of congenital anomalies:
- Cardiac—especially VSD, ASD, transposition
- Small left colon syndrome (transient delay in development of left side of colon; presents with abdominal distention)
- Caudal regression syndrome: spectrum of structural neurologic defects of the caudal region of spinal cord which may result in neurologic impairment (hypo, aplasia of pelvis & LE)

Respiratory Disorders

RDS: respiratory distress syndrome
TTN: transient tachypnea of the newborn
MAS: meconium aspiration syndrome
Diaphragmatic hernia

Gastrointestinal and Hepatobiliary Disorders

Physiologic Jaundice	Pathologic Jaundice
Appears on second to third DOL (term)	May appear in first 24 hours of life
Disappears by fifth DOL (term)—7th	Variable
Peaks at second to third DOL	Variable
Peak bilirubin <13 mg/dL (term)	Unlimited
Rate of bilirubin rise <5 mg/dL/d	Usually >5 mg/dL/d

Note. Work up for possible pathologic hyperbilirubinemia when:

It appears on the first day of life
Bilirubin rises >5 mg/dL/day
Bilirubin >13 mg/dL in term infant
Direct bilirubin >2 mg/dL at any time

Breast-Feeding Jaundice versus Breast-Milk Jaundice

Breast-feeding jaundice means that a baby is not nursing well and so not getting many calories. This is frequent in first-time breast-feeding mothers. The infant may become dehydrated; however, it is lack of calories that causes the jaundice. The treatment is to obtain a lactation consultation and rehydrate the baby. The jaundice occurs in the first days of life.
Breast-milk jaundice occurs due to a glucoronidase present in some breast milk. Infants become jaundiced in week 2 of life. Diagnosis and treatment is phototherapy if needed. Although the bilirubin may rise again, it will not rise to the previous level. The baby may then be safely breast fed. Problem gone by 2–3 months.

Hyperbilirubinemia and Jaundice

Etiology	Reason for increased bilirubin	Hyperbilirubinemia	Hgb, Hct/ Reticulocytes	Other labs	Treatment
Excessive bruising/ cephalohematoma	RBCs → Hgb → Bilirubin	Indirect	• Normal to slightly low Hgb/Hct • Normal to slight increase in reticulocytes		Phototherapy
Immune hemolysis • Rh • ABO • Minor blood groups	Anti-Rh, anti-A, anti-B, anti-minor blood group Abs	Indirect	• Low Hgb/Hct (anemia) • Increased reticulocytes	• Rh negative mother and Rh positive baby • Type O mother and type A or B baby • Direct Coombs positive • Decreased RBCs	Phototherapy + possible exchange transfusion
Polycythemia	High Hct, Hgb → high bilirubin	Indirect	High (Hct >65)/ normal	Increased RBCs	Phototherapy + partial exchange transfusion
Non-immune hemolysis	Abnormal RBC → splenic removal	Indirect	Low (anemia)/ increased	• If no membrane defect → G6PD, PK activity • Characteristic RBCs if membrane defect • Decreased RBCs	Phototherapy + transfusion
Displacement of bound bilirubin from albumin	Free bilirubin in circulation	Indirect	Normal		Treat underlying problem
Familial nonhemolytic hyperbilirubinemia (Crigler-Najjar syndrome)	Absence of glucuronyl transferase (type I) vs. small amount of inducible GT (type II)	Indirect	Normal	GT activity	Phototherapy + exchange transfusion
Extrahepatic obstruction—biliary atresia	Bilirubin cannot leave the biliary system	Direct	Normal	Ultrasound, liver biopsy	Portojejunostomy, then later liver transplant
Cholestasis (TORCH, sepsis, metabolic, endocrine)	Abnormal hepatic function → decrease bilirubin excretion	Direct	Normal	With H and P, other select labs suggestive of underlying etiology	Treat underlying problem
Bowel obstruction	Increased enterohepatic recirculation	Indirect	Normal		Relieve obstruction + phototherapy
Breast feeding jaundice	Increased enterohepatic recirculation	Indirect	Normal		Phototherapy + hydration + teach breast feeding
Breast milk jaundice	Increased enterohepatic recirculation	Indirect	Normal		Phototherapy + continued breast feeding

INFECTIONS

Neonatal Sepsis

Most common organisms: group B Streptococcus, coli, and Listeria monocytogenes.

Transplacental Intrauterine Infections (TORCH)

Most TORCH infections are acquired in first or second trimester. Most infants have IUGR.

Toxoplasmosis; Other (syphilis, varicella, HIV, and parvovirus B19); Rubella; Cytomegalovirus (CMV); Herpes

TORCH Infections

Many of the findings of the TORCH infections are very similar, so the following gives the most likely presentation:

Toxoplasmosis—hydrocephalus with generalized calcifications and chorioretinitis
Rubella—the classic findings of cataracts, deafness, and heart defects
CMV—microcephaly with periventricular calcifications; petechiae with thrombo- cytopenia
Herpes—skin vesicles, keratoconjunctivitis, acute meningoencephalitis
Syphilis—osteochondritis and periostitis; skin rash involving palms and soles and is desquamating; snuffles (mucopurulent rhinitis)

SUBSTANCE ABUSE AND NEONATAL WITHDRAWAL

Neonatal Features of Maternal Major Illicit Drug Use

Opiates	Cocaine
High incidence LBW, most with intrauterine growth restriction	No classic withdrawal symptoms
Increased rate of stillborns	Preterm labor, abruption, asphyxia
No increase in congenital abnormalities	Intrauterine growth restriction
Early withdrawal symptoms, within 48 hours	Impaired auditory processing, developmental delay, learning disabilities
Tremors and hyperirritability	High degree of polysubstance abuse
Diarrhea, apnea, poor feeding, high-pitched cry, suck, weight loss, tachypnea, hyperacusis, seizures, others	CNS ischemic and hemorrhagic lesions
Increased risk of SIDS	Vasoconstriction → other malformations

Definition of abbreviations: CNS, central nervous system; LBW, low birth weight; SIDS, sudden infant death syndrome.