Which of the following symptoms would suggest a complication of chronic urinary reflux in a patient?

Chronic urinary reflux, particularly in the context of vesicoureteral reflux, can lead to significant complications primarily due to the resulting damage to the kidneys. Over time, this condition may cause renal scarring and decreased kidney function, which can manifest as hypertension and proteinuria.

Hypertension in this context is often due to increased workload on the renal vasculature and activation of the renin-angiotensin-aldosterone system as a response to kidney injury. Proteinuria indicates that the glomerular filtration barrier is compromised, often a result of nephron damage from chronic reflux nephropathy.

In contrast, acute flank pain typically points to renal calculi or pyelonephritis rather than a complication directly correlated with chronic urinary reflux. Hematuria can have various causes, including infection and trauma, but it is not specific to the complications of urinary reflux. Nausea and vomiting are common symptoms that can arise from kidney issues but are not definitive indicators of chronic urinary reflux complications. Thus, hypertension and proteinuria are direct indicators of the lasting consequences chronic urinary reflux may have on kidney health.