Normal BUN and Creatinine, but abnormal ration

[drderf]

I know partially wrong topic, but any thing to worry about if my 9yo WM had a nigh normal BUN, Low Normal Creatinine, resulting in a high ratio?

He has has persistent fracture and join pain in one ankle.  All other blood work normal.
(ANA) not back yet.

Medical History + for asthma; stable now. and occasional nosebleeds

[Deanna L Aftab Guy, MD]

repeated fractures are worrisome, however in the same ankle make me think more of an anatomical problem or risk versus an endocrine problem, is he seeing a pediatric orthopedist and be sure that the xrays are accurately diagnosing and they are true fractures. Poor kid!

[drderf]

Thank you for the reply, it does make me feel better.  I should have mention that the he has had approximately 4 to 5  fractures in the same ankle over the past year as well

[Deanna L Aftab Guy, MD]

the ratio is deceiving and not usually something to pay much attention to, the absolute bun reflects blood urea nitrogen and can reflect the concentration of the blood or even body muscle mass, so when slightly elevated we think a little less fluid on board as our first impression.
Creatinine normal as is bun regardless of high or low normal it is in normal range.
The joint pain and fracture of his ankle should be addressed by ortho to see if he has joint instability, endocrine wise as this is my area, I would assess but not aggressively unless we see other reasons, looking at bone issues like parathyroid hormone, vitamin D levels and an enzyme called alk phos, as well as calcium, phosphorus and even thyroid.
The nosebleeds sound allergy related given he has asthma and unless he is on mega doses of steroids for asthma there is an unlikely chance that the asthma is related to the ankle fracture.
My bet is he is just having simple injury to the ankle with pain related to the healing and may need some physical therapy and assessment of his footwear (orthotics?)