Case 4

Since we are unsure how consistently Miss Kitty has been getting her methimazole, you decide to leave her current dose the same but to try a transdermal formulation instead. It is important to continue to monitor her renal values as her thyroid concentrations are normalized, so you recommend she return in a couple of weeks for reevaluation.

At her next visit, the owner reports that Miss Kitty is still doing well. She is active, eating well, and is maybe drinking less water, although in the interim the family has acquired a new kitten and has not been able to monitor water intake as well. Miss Kitty has gained 1 lb since her initial visit! These are her bloodwork results:

CBC

Unchanged

Serum chemistry panel

Patient values

Reference range

BUN (mg/dl)

53

14-36

Creatinine (mg/dl)

3

0.6-2.4

Phosphorus (mg/dl)

9

2.4-8.2

T4 (µg/dl)

1.8

1-4

(Her bladder was empty so you were unable to obtain a urine sample at this time.)

QUESTION 5

Which of the following recommendations would you make at this time based on this new information?

a) Recommend that the methimazole dose stay the same but add calcitriol to her treatment.

b) Discontinue the methimazole treatment at this time and recheck her again in one month.

c) Recommend no changes at this time. She is doing well clinically despite the elevation of her renal values and her hyperthyroidism is regulated, so continue the current regimen.

d) Discuss I-131 treatment with the owner since that will have less of an effect on her renal perfusion.

<< Back | Next Step >>