Chapter 12: The Newborn – Hematology, Neurology, Renal, Eye, Infection, Neoplasia, Metabolic

Anemia/bleeding/polycythemia · Neonatal seizures, HIE, IVH · Renal agenesis, PUV, AKI · Eye: cataract, ROP, glaucoma · Immunity, TORCH, sepsis · Neonatal tumors (neuroblastoma, leukemia) · Inborn errors, hypoglycemia, CAH

📌 Core principles: Neonatal hematology – anemia (hemolytic, iatrogenic), polycythemia, thrombocytopenia, bleeding disorders. Neurology – seizures, HIE, IVH, stroke, metabolic encephalopathy. Renal – congenital anomalies, hydronephrosis, AKI. Eye – ROP screening, congenital cataracts, glaucoma. Infection – early/late sepsis, TORCH, HSV, meningitis. Neoplasia – neuroblastoma, leukemia, sacrococcygeal teratoma. Metabolic – CAH, hypoglycemia, aminoacidopathies, galactosemia.

📖 Core summary: neonatal hematology, neurology, renal, eye, infection, neoplasia, metabolic

🩸 Hematological problems
Anemia: hemolytic (ABO/Rh), iatrogenic, hemorrhage. Polycythemia (Hct >65%): hyperviscosity, thrombosis, hypoglycemia. Thrombocytopenia: immune (NAIT), sepsis, DIC. Hemorrhagic disease (vitamin K deficiency).
🧠 Neonatal neurology
Seizures: subtle, tonic, clonic, myoclonic. HIE (hypothermia). IVH (preterm). Stroke (arterial ischemic, sinovenous). Metabolic encephalopathy (hypoglycemia, electrolyte, inborn errors).
💧 Renal disease
Congenital anomalies: renal agenesis, PUV, hydronephrosis, cystic kidney disease. Acute kidney injury (prerenal, intrinsic, obstructive). Renal vein thrombosis. Hyponatremia, hyperkalemia, acidosis.
👁️ Eye problems
ROP (retinopathy of prematurity) – screen <30 wk or <1500g. Congenital cataract (rubella, metabolic). Glaucoma (buphthalmos, cloudy cornea). Conjunctivitis (chemical, gonococcal, chlamydia).
🦠 Infection & immunity
Early‑onset sepsis (GBS, E. coli). Late‑onset (CoNS, Candida). TORCH: toxoplasmosis, rubella, CMV, HSV, syphilis, VZV, parvovirus. Immune deficiencies (SCID, neutrophil disorders).
🎗️ Neonatal neoplasia
Neuroblastoma (adrenal mass, skin nodules). Leukemia (congenital ALL/AML). Retinoblastoma (leukocoria). Sacrococcygeal teratoma. Renal tumors (mesoblastic nephroma).
⚗️ Metabolic disorders
Hypoglycemia (hyperinsulinism, GSD). CAH (salt‑wasting crisis). Aminoacidopathies (MSUD, PKU, urea cycle). Galactosemia (jaundice, E. coli sepsis). Fatty acid oxidation disorders (cardiomyopathy, hypoketotic hypoglycemia).

📊 Key neonatal screening: Newborn metabolic screen (PKU, MCAD, CAH, galactosemia, CF, hypothyroidism). CCHD pulse oximetry. Hearing screen. ROP exam.

🔍 Approach to neonatal problems

Seizures in newborn – EEG, metabolic panel (glucose, Ca, Mg, Na), blood gas, septic workup, consider HIE, CNS imaging (cranial US, MRI).

Jaundice with conjugated hyperbilirubinemia – Rule out biliary atresia, TORCH, sepsis, metabolic (galactosemia). Ultrasound, liver biopsy, cholangiogram.

Abdominal mass – Ultrasound: neuroblastoma (adrenal), Wilms (rare neonatal), mesoblastic nephroma, multicystic kidney, hydronephrosis.

Poor feeding + lethargy + tachypnea + shock – Consider sepsis, metabolic crisis (CAH, urea cycle defect, galactosemia), ductal‑dependent CHD.

Eye exam for ROP – Initiate at 31 weeks PMA or 4 weeks postnatal age for ELBW. Follow until full vascularization.

📋 Stepwise management protocols

Symptomatic polycythemia (Hct >70%, hyperviscosity) – Partial exchange transfusion (10‑20 mL/kg with saline or plasma).

Neonatal alloimmune thrombocytopenia (NAIT) – Maternal HPA‑1a antibodies. IVIG 1 g/kg/day ×2 days, platelet transfusion (HPA‑1a negative).

Congenital adrenal hyperplasia (salt‑wasting crisis) – IV hydrocortisone, normal saline bolus, dextrose, monitor electrolytes, mineralocorticoid (fludrocortisone).

Suspected congenital toxoplasmosis – Maternal spiramycin, neonatal pyrimethamine + sulfadiazine + folinic acid, eye exam, neuroimaging.

Congenital neuroblastoma – Staging: US, CT/MRI, urine catecholamines (VMA/HVA). Low stage often self‑regress. High stage chemotherapy/surgery.

Hypoglycemia unresponsive to IV dextrose – Consider hyperinsulinism: glucagon 0.03 mg/kg, diazoxide, octreotide. Endocrine consult, genetic testing (ABCC8, KCNJ11).

⚡ Key reminder: Newborn metabolic screening (heel prick) 24‑48h identifies most inborn errors before clinical decompensation. Any sick neonate – think metabolic cause if sepsis ruled out and acidosis/hypoglycemia present.

🧠 Reflex prompts – neonatal subspecialty problems

🩸 Newborn with Hct 72%, jittery, hypoglycemic:
Symptomatic polycythemia → partial exchange transfusion. Also monitor for thrombosis.
🧠 Term newborn with subtle seizures, EEG normal, hypocalcemia (Ca 5.5 mg/dL):
Early‑onset hypocalcemia (preterm, IDM, asphyxia). IV calcium gluconate.
💧 Anuria first 24h, flank mass, single umbilical artery:
Rule out bilateral renal agenesis or obstructive uropathy (PUV). Renal US, VCUG.
👁️ Preterm 26 wk, now 32 wk PMA – indication for ROP exam:
First exam at 31 weeks PMA (or 4 weeks postnatal). ROP treatment if type 1 pre‑plus disease.
🦠 Vesicular rash, thrombocytopenia, elevated transaminases, microcephaly:
Congenital HSV or varicella. IV acyclovir, CSF PCR.
⚗️ Neonate with vomiting, dehydration, hyperkalemia, hyponatremia, shock:
Classic salt‑wasting crisis – congenital adrenal hyperplasia (21‑hydroxylase deficiency). IV steroids, fluids.