Pediatric Cardiology and Hematology Flashcards
The NEW, FANCY test for hereditary spherocytosis
- Eosin-5-maleimide binding test
- Analyzes the interaction between a dye and certain proteins on the RBC surface through flow cytometry
- Fast, highly sensitive, highly specific
- Now preferred to the osmotic fragility study for diagnosis of hereditary spherocytosis
Bleeding time is a simple but sensitive marker of ___
Bleeding time is a simple but sensitive marker of platelet function
Do not confuse this for a coagulation test
Eisenmenger syndrome may occur in. . .
- VSD (within months of birth)
- ASD (later in life, often young adulthood)
- Patent ductus arteriosus
- The three forms of acyanotic congenital heart disease
Why doesn’t VSD have fixed split S2?
Think about it this way:
An ASD allows for an increase in RV preload
A VSD does not increase RV preload by as much since the AV valve has closed and precludes the RV from filling through the pulmonary vein by way of the LA
You close an ASD with ___.
You close a VSD with ___.
You close an ASD with a device (interventional radiology).
You close a VSD with surgery.
Tetralogy of Fallot is a ___ associated with ___.
Transposition of the great vessels is a ___ associated with ___.
Tetralogy of Fallot is an endocardial cushion defect associated with Down syndrome.
Transposition of the great vessels is a failure of embryologic heart twisting associated with diabetes mellitus (not gestational).
TET spell
Kid who is blue and then pinks up when he squats
Pathognomonic for tetralogy of Fallot
Claudication in a child is highly suggestive of. . .
. . . coarctation of the aorta
Hemoglobin A2
Alpha2 Delta2
Found at low levels in normal adult human blood
Embryonic hemoglobin
- Four types:
- Hb Gower I: ζ2ε2
- Hb Gower II: α2ε2
- Hb Portland I: ζ2γ2
- Hb Portland II: ζ2β2
- The Gower forms are the main ones produce in the yolk sac blood islands during embryonic development
- The Portland forms are more scarce and unstable, present at only small amounts during embryonic and fetal development
A patient with sickle cell disease is expected to have a ___ creatinine
A patient with sickle cell disease is expected to have a low creatinine
This is due to the hyperfiltration that occurs in the early stages of sickle cell disease due to episodic microvascular renal obstruction from sickled cells, particularly in the medulla.
If a patient with sickle cell disease has a high-normal creatinine, it may indicate an AKI
A patient with sickle cell disease is much more likely to have __ gallstones
A patient with sickle cell disease is much more likely to have pigmented gallstones
What labs do you probably want baselines for in your sickle cell patients?
- Bili
- Hgb
- Retic count
- LDH
- Cr
Deferoxamine
Strong chelator of iron and aluminum
Given to patients with iron overload from chronic transfusions, such as sickle cell or thalassemia major patients
Transfusing 1 unit of red cells is roughly equivalent to having ___ worth of iron supplements
Transfusing 1 unit of red cells is roughly equivalent to having 1 years worth worth of iron supplements
So, if someone is getting transfused, they should NOT take supplemental iron
For all intents and purposes, you should assume that any patient with sickle cell disease has no ___.
For all intents and purposes, you should assume that any patient with sickle cell disease has no spleen.
Penicillin prophylaxis in sickle cell disease
Given from birth to age 5 due to poor splenic function
Some may need it until adulthood. They will also need full pneumococcal vaccination (13-valent and 23-valent).
How to think about osteomyelitis etiologies and sickle cell
Someone with sickle cell who gets osteomyelitis is still most likely to have Staph aureus, just like everybody else. S. aureus is just the most common cause of osteomyelitis in everyone, far and away. Salmonella is the second most common cause in those with sickle cell disease.
However, if someone presents with Salmonella osteomyelitis, you should ask yourself if they have sickle cell disease. Only people with sickle cell disease get Salmonella osteomyelitis. But, not every sickle celler with osteomyelitis has Salmonella.
Managing avascular necrosis of bone in sickle cell patients
- Often will involve the hip
-
Conservative management for 4-6 months (crutches, NSAIDs) is the approach of choice
- If no improvement, go to surgery
Indications for exchange transfusion in sickle cell disease
- Stroke
- Acute chest (chest pain, dyspnea,lung infiltrate)
- +/- Priapism (try drainage of penis first)
Treating sickle cell crisis
- Exchange transfusion emergently if indicated (acute chest, stroke, +/- priapism)
- Otherwise (most cases):
- IV fluids
- Oxygen
- Pain control
- If evidence of infection, treat appropriately
- Follow-up with psychosocial stressors if presenting in crisis with normal labs
Hb SC disease
Low Hb, but no or extremely rare sickle cell crises
Hb Sβ+
- One copy S, one β+ (β with slightly lower expression)
- Mild form of SS disease
Hb Sβ0
- One copy Hb S, one absent β allele
- Most severe form of SS disease
Who should get PGE1 therapy? (congenital heart disease)
- All unstable infants with suspected CHD of any etiology
Tricuspid atresia
- Type of cyanotic congenital heart disease
- Will present as soon as ductus arteriosus begins to close (first 4 days of life)
- LVH will usually be present
- Treat w/ PGE1 as bridge to surgery
Duke criteria
Howell-Jolly bodies
Red cells with nuclear remnants. Seen in patients with asplenia or poor spleen function (as in sickle cell, for example)
Diagram of congenital platelet defects
HUS vs aHUS vs TTP
- HUS Triad: Acute renal failure, MAHA, thrombocytopenia in the setting of recent dysentery and without fever, in children
- aHUS Pentad: Prominent acute renal failure,MAHA, thrombocytopenia, fever, and sometimes neurologic symptoms,in adults without Hx dysentery
- TTP Pentad: Sometimes acute renal failure, MAHA, thrombocytopenia, fever, and prominent neurologic symptoms, in adults without Hx dysentery
- Neurologic symptoms = AMS
