Final answer:
The first-listed diagnosis for the office visit is hypertension since the purpose was to manage the patient's known condition of elevated blood pressure, despite the observation of bruising.
Step-by-step explanation:
The first-listed diagnosis for a female patient seen in the office for a follow-up of hypertension would be hypertension itself. This is because the purpose of the visit was to manage and follow-up on her known chronic condition of elevated blood pressure.
The bruising observed by the nurse may warrant further investigation, but it is not the primary reason for the visit, nor is it necessarily related to hypertension or the medication hydrochlorothiazide, which was prescribed to help manage her blood pressure.
It's important to add that hypertension is a condition where the blood pressure measurements of 140/90 mm Hg or above are considered hypertensive.