#paediatric nephrology

[mdrambles]

PGY-3 Pearl #3: A Rolling Stone Gathers No Moss

One of our peds nephrologists told me today

“There are only 2 things you need to know about nephrolithiasis in children for your Pediatric Specialty Exam:

The most common type of stone in children is calcium oxalate

The most common type of stone in children with IBD is calcium oxalate”

One of my colleagues later helped explain why children with IBD have an increased propensity for kidney stones, particularly of the calcium oxalate variety:

“Normally, there is enterohepatic circulation of oxalate which binds to calcium in the bowel and is excreted. In IBD, there is less nutrient absorption, and in particular, excess fat traps calcium in the gut, thereby increasing the amount of free oxalate that is later reabsorbed in the colon. This same physiology occurs in IBD and other conditions with steatorrhea (e.g. CF), as well as in short bowel syndrome.”

[mdrambles]

PGY-2 Pearl #21

When you have identified a patient requiring pharmacologic hypertension management (ie/meets criteria for stage II hypertension or critical hypertension per AAP 2017 pediatric hypertension guidelines, and/or symptomatic from hypertension), think about the underlying mechanism for hypertension in that patient.

Then, think about the ABCD’s of hypertension:

A: ACE inhibitors (for increased RAAS activation, decreased vascular tone; will decrease GFR and via decreased kidney perfusion by vasconstricting afferent arteriole of the glomerulus)

B: beta blockers (decreases HR --> decreases cardiac output --> decreases BP)

C: calcium channel blockers (e.g. amlodipine, nifedipine; decreases peripheral vascular resistance) typically a safe choice if the underlying mechanism of hypertension is not clear/unknown

D: diuretics (decreases fluid volume to decrease preload)