The must-know core facts per system that the Saudi/Gulf pediatric Prometric tests again and again, aligned with the question bank's answer keys.
| Normal / reassure | Red flag / act |
|---|---|
| Acrocyanosis (hands, feet) in first 24–48 h | Central cyanosis → pulse oximetry, echo |
| Moulding, caput, subconjunctival hemorrhage | Absent or white red reflex → ophthalmology before discharge (cataract, retinoblastoma, glaucoma) |
| Epstein pearls, breast engorgement, 'witch's milk', pseudomenses, vaginal tag | Weak/absent femoral pulses → coarctation, duct-dependent lesion |
| Small sacral dimple: <5 mm, <2.5 cm from anus, base visible | Dimple >5 mm or high, hair tuft, hemangioma, skin tag → spinal US/MRI |
| Preauricular pit (check hearing screen) | Midline scalp/nasal swelling enlarging with crying → encephalocele: MRI before any needle |
| Positional foot, flexible metatarsus adductus | Ortolani/Barlow positive → hip US and orthopedics |
| Umbilical hernia, non-communicating hydrocele | Bilateral impalpable testes or ambiguous genitalia → karyotype + 17-OHP (CAH) |
Also not normal: jaundice in the first 24 h, no meconium by 48 h, bilious vomiting, no urine by 24 h, single umbilical artery with other anomalies (renal/cardiac search).
| Lesion | Timing / site | Key clue |
|---|---|---|
| Erythema toxicum | Day 1–3, face/trunk, spares palms/soles | Red blotches with central pustule, eosinophils, well baby |
| Transient pustular melanosis | Present at birth, darker skin, chin/neck/shins | Fragile pustules → collarette → brown macules; neutrophils |
| Milia | Nose, chin | Pearly white keratin papules; resolve in weeks |
| Miliaria | Flexures, overheating | Clear vesicles or red papules; cool the baby |
| Neonatal acne | 2–4 weeks, cheeks | No comedones; self-limiting |
| Mongolian spot | Sacrum/buttocks from birth | Blue-grey, fades in childhood; document (not a bruise) |
| Salmon patch | Nape, eyelids, glabella | Fades (nape may persist) |
Not benign: vesicles (HSV → acyclovir), V1 port-wine stain (Sturge–Weber → eye and brain review), ≥6 café-au-lait macules (NF1), ash-leaf macules (tuberous sclerosis), rapidly growing hemangioma near eye/airway/beard area (propranolol).
| Fetal structure | Function | Closure / remnant |
|---|---|---|
| Umbilical vein (1) | Oxygenated blood from placenta (highest SpO2) | Ligamentum teres |
| Ductus venosus | Umbilical vein → IVC, bypasses liver | Ligamentum venosum |
| Foramen ovale | RA → LA | Functional closure in minutes–hours (LA pressure > RA); fossa ovalis; probe-patent in ~25% adults |
| Ductus arteriosus | Pulmonary trunk → descending aorta (distal to left subclavian) | Functional closure 1–3 days, anatomical 2–3 weeks; ligamentum arteriosum |
| Umbilical arteries (2) | Deoxygenated blood to placenta | Medial umbilical ligaments |
Failure of PVR to fall = PPHN (persistent fetal circulation): pre-ductal SpO2 higher than post-ductal, structurally normal heart → oxygen, ventilation, inhaled nitric oxide.