Pop Quiz: Mind the (protein) Gap

Below you will find a brief pop quiz in follow up to Dr Doan's wonderful case of Multiple Myeloma presenting as profound AKI (Cr 8!).

1) What two labs do you need to identify a protein gap?

2) Name two infectious causes of an elevated protein gap?

3) What is the most common presenting symptom of the CRAB criteria?

4) What are the two "magic numbers" for abnormal values of the CRAB criteria?

5) What is the "money" finding of multiple myeloma on peripheral smear?



1) serum protein - serum albumin = protein gap 2) HIV, Hep C 3) Bone Pain (CRAB is written in least to most common order of symptoms: #1 bone pain, #2 renal failure, #3 anemia, #4 hypercalcemia) 4) 10 and 2! (Ca > 10.2, Hg < 10, sCr >2) 5) Rouleax Formation (French for "cylindrical roll of coins")

How'd you do?