You must be logged in to vote!
mousie
Anion Gap: Na - (Cl + HCO3) = normally around 10-12
+5
seagull
good to know. I keep looking up the urine values but all it said was "varies", then I threw my computer and yelled "does that vary Mother F****ers. I do feel better now.
+80
_yeetmasterflex
glad I wasn't the only one who got very pissed off at the urine values
+4
fulminant_life
Usually the first thing I look at is whether or not the Cl- is high. Generally if the Cl- is high its going to be a normal gap
+9
henoch schonlein
i think they gave you the urine values bc you can calculate the URINE anion gap which is (Na + K - Cl). In this case the Urine Anion Gap is positive (5). Boards and Beyond mentions that a positive UAG is due to Renal Tubular Acidosis Type 1 (inability of alpha intercalated cells to secrete hydrogen ions). just another approach to answer this q
+23
270onstep1
Actually diarrhea is the "D" in "HARDASS"(reason why I was stuck between Chron's and RTA). Ended up getting it right with RTA..
+1
talha_s
So the reason this is not Crohn's disease is actually what BnB explains in Renal Tubular acidosis video. Anytime there is a Metabolic Acidosis with intact kidney secretion of H+, the URINARY Anion gap (Na+K-Cl) is NEGATIVE. This is because the excess NH4 that is secreted into urine is combined with Cl-. Therefore, in Crohn's disease and Type 2 Renal Tubular Acidosis, the urinary anion gap is NEGATIVE.
In this question, the urinary anion gap is POSITIVE so this would be an example of Type 1 RTA because the kidney can not excrete H+.
I got it right by chance, definitely did not understand it in this much detail when I was answering it lol
+11
You must be logged in to vote!
You must be logged in to vote!
You must be logged in to vote!
subclaviansteele
My take is that hes not super acidotic and the K is at the low end.
+
nwinkelmann
see the comment by @zbird, which explains that the urine anion gap is important (which I took to interpret as more important than the serum K+ level, lol, because the normal K threw me off too).
+
You must be logged in to vote!
krewfoo99
Why would the urine Potassium be so high if it is type 1 ? Shouldnt it be type 2?
+
drpatinoire
@krewfoo99 I think it's RTA2 (Fanconi syndrome), he is losing all kinds of Na, K, Cl which should be reabsorbed in PCT.
+1
misterdoctor69
@Drpatinoire: it can't be RTA2 because the urine anion gap (UAG) is positive (+), which implies that the patient is unable to secrete H+ (via NH4+, which couples w/ Cl-). RTA2 on the other hand has a negative (-) UAG because RTA2 affects only the proximal tubule's ability to reabsorb bicarbonate (i.e. H+ secretion via NH4+ in the distal convoluted tubule is unaffected).
+
You must be logged in to vote!
drpatinoire
If she has Crohn, she has already lost a lot of K, HCO3-, then the compensatory system wouldn't let her keep losing electrolytes in her urine.
+1
You must be logged in to vote!
daddyyikes
other than the patient not haveing any sxs of crohn's i dont see any reason why its not crohn's. we differ crohn's and rta by urine anion gap. in chronic diarrhoea it is negative while in rta its +ve but in question the anion gap was normal
+
You must be logged in to vote!
submitted by โbrethren_md(105)
Requires knowing how to calculate an anion gap - look it up. In this case, it is a normal anion gap metabolic acidosis. Know the mneumonics MUDPILES and HARDASS. Renal Tubular acidosis is the only answer choice that is an example of a normal anion metabolic acidosis.