Pierre-Robin Sequence

pierre-robin-sequence

Pierre-Robin Sequence is not a syndrome, it’s a sequence. While it is a collection of features, one happens because of the one that came before.

The features are:

  • Retrognathia/micrognathia (posterior mandible or very small mandible)
  • Glossoptosis (downwards/posterior displacement of the tongue due to the small mandible
  • Airway obstruction (because the tongue is in the way)

Pierre-Robin Sequence is associated with cleft palate (50% of children with the sequence have cleft palate). There are two proposed theories:

  1. The first is that the tongue simply gets in the way of the palate from fusing
  2. The second is that the tongue prevents the newly fused palate from staying fused (this is currently the more popular theory)

PRS, though not a syndrome itself, is associated with multiple syndromes including Stickler Syndrome, velocardiofacial syndrome, fetal alcohol syndrome and Treacher Collins Syndrome.

PHACE Syndrome (hemangiomas)

PHACE_syndromeThere are no shortage of congenital syndromes that are acronyms arranged into some sort of vaguely pronounceable word. There will be lots of doodles about these, but we’ll start off with a more uncommon one – PHACE Syndrome.

PHACE Syndrome is a collection of findings that go along with large infantile hemangiomas. They’re the more worrisome (but less obviously disfiguring) things you need to look for when you see a baby with a large hemangioma on the face or multiple hemangiomas.

  • Posterior fossa brain malformations
  • Hemangiomas
  • Arterial anomalies
  • Cardiac anomalies and coarctation of the aorta
  • Eye abnormalities
  • Sternal cleft

The most common symptom of PHACE is cerebrovascular abnormalities, followed by cardiac anomalies (coarctation, aortic arch anomalies, VSDs). If you suspect PHACE, do clinical exam of the skin and eyes and MRI of the head, neck and chest.

Other cool facts

  • PHACE occurs in full-term normal birth weight infants (other hemangiomas tend to occur in preterm infants)
  • Quite common, more girls than boys (8:1)
  • Don’t confuse it with Strurge-Weber (port wine stain, associated with the facial dermatomes)
    • Port wine stains don’t proliferate and then regress like an infantile hemangioma

Maculopapular Childhood Rashes

rashes

BUY THIS AS A STUDY CARD

A kid without a rash just isn’t a kid.

Chicken Pox

  • Incubation: 10-21d, infective until crusted over
  • Rash: vesicles on macules (dewdrops on rosepetals),
  • Very pruritic!
  • Other symptoms: 1-3d prodrome of fever and respiratory symptoms
  • Treatment: supportive, acyclovir for severe disease, VZIG for post-exposure prophylaxis
  • Complications: 1st or 2nd trimester = congenital varicella syndrome

Roseola

  • Incubation: 5-15d
  • Rash: pink macules and maculopapules, starts on neck.
  • Non-pruritic!
  • Other symptoms: HIGH FEVER, cough, respiratory symptoms, erythematous pharynx, tonsils & TMs
  • Treatment: supportive
  • Complications: febrile seizures
  • * Generally affects kids <5 years old

Measles

  • Incubation: 10-14d, dx with measles IgM
  • Rash: maculopapular, starts on face.
  • Non-pruritic!
  • Other symptoms: the 3 Cs
    • 1) Cough 2) Coryza (runny nose) 3) Conjunctivitis
    • Koplik spots in mouth 1-2d before rash
  • Treatment: supportive, prophylactic Ig
  • Complications: secondary bacterial infection, encephalitis (1:1000), subacute sclerosing panencephalitis (1:100000)

Rubella aka German Measles

  • Incubation: 14-21d, infective 5d before rash and 7d after
  • Rash: pink maculopapular, starts on face.
  • Pruritic!
  • Other symptoms: non-specific
  • Treatment: supportive
  • Complications: congenital rubella syndrome (very bad*), first four months of pregnancy highest risk (this is why we check rubella immunity status in prenatal screening)

* Congenital Rubella Syndrome
“Blueberry muffin baby” (purpura). Cataracts/congenital glaucoma, congenital heart disease, hepatosplenomegaly, jaundice, microcephaly, developmental delay

Fifth Disease aka Erythema Infectiosum

  • Incubation: 4-14d, infective prior to onset of rash
  • Rash: slapped cheeks (raised uniform maculopapular lesions on cheeks), may appear on extensor surfaces
  • Usually not pruritic
  • Other symptoms: flu-like illness ~3d prior to rash
  • Treatment: supportive, blood transfusions if aplastic crisis
  • Complications: arthritis (10%), vasculitis
    • Aplastic crisis: reticulocytopenia, not bad in normal people, very bad anemia if you already have chronic hemolytic anemia
    • During pregnancy: fetal hydrops/fetal loss

* This is a good one to actually know the virus name! PARVOVIRUS B19

Other rash descriptors to think about

  • Sandpaper rash: scarlet fever (Group A Strep), they also have strawberry tongue, fever and sore throat
  • Pink macules with central clearing: erythema marginatum (one of the major Jones criteria for rheumatic fever)
  • Palpable purpura: Henoch-Schonlein Purpura
  • Non-blanching petechiae: BAD (meningococcal disease), could be other things too, but need to rule out meningitis

Acyanotic vs Cyanotic Congenital Heart Defects

You separate congenital heart defects into acyanotic and cyanotic. Basically, is the baby (or kid) nice and pink, or is he or she dusky as they like to say. Sometimes the blueishness only happens when they’re working really hard, like feeding and crying (or thinking about the pathophysiological mechanisms of heart disease).

One of the important things to remember is that acyanotic heart defects can switch over if they’re left alone for too long because of pulmonary hypertension caused by the extra flow. This is called Eisenmenger Syndrome.

It’s also important to realize that many of the cyanotic lesions are duct dependent, meaning that as long as the ductus arteriosus is open, they are happy and pink. The problems start in that time 6-24h after delivery when the ductus closes. Thankfully you can keep it open by giving prostaglandin E1.

Need the ductus for systemic circulation:

  • Coarctation of the aorta
  • Critical aortic stenosis
  • Hypoplastic left heart syndrome

Need the ductus for pulmonary circulation:

  • Pulmonary atresia
  • Critical pulmonary stenosis
  • Tricuspid atresia
  • Tetralogy of fallot

Also, I realize that the 5 Ts of cyanotic heart lesions are a pentad of 6 (plus some), but mnemonics can only do so much, and the T thing is just so catchy.

For a more detailed illustration of PDAs, you can check out this doodle!

Anatomy of the ear

Who knew that the ear could have so many parts to it? This is getting into some detailed anatomy, but you will be able to impress your staff person with your incredible knowledge.

As a side note, you may also be able to impress your local piercer, as most of the more unusual ear piercings are simply named after the bit of ear the hole is going through.

Patent ductus arteriosus

Normal fetal circulation

The ductus arteriosus is a connection between the aorta and pulmonary artery present in the fetal circulation. Since the pulmonary vascular pressure is higher than the systemic pressure, blood is shunted through the ductus from the right to the left, bypassing the lungs.

 

When the baby is born, the resistance in the pulmonary vascular falls and more of the blood goes through the lungs. In conjunction with this the fall in the level of circulating prostaglandins causes the contraction of the ductus arteriosus.

Patent ductus arteriosus

In some babies, particularly those born prematurely, the ductus fails to close and the shunt becomes left to right.

This gives you the classic “continuous machine-like murmur