A healthy 14-year-old female has a dipstick urinalysis positive for 5-6 RBCs per high-power field but otherwise normal. What is the first question the PCPNP should ask?

A healthy 14-year-old female has a dipstick urinalysis positive for 5-6 RBCs per high-power field but otherwise normal. What is the first question the PCPNP should ask?

• A. Are you sexually active?
• B. Are you taking any medications?
• C. Have you had a recent fever?
• D. When was your last menstrual period?

Answer: (D)

Contamination from menstrual blood is the most common pitfall when interpreting a urinalysis in a teenage girl. A sample collected around the time of a period can show red blood cells on microscopy or appear positive for blood on the dipstick, even if there isn’t a urinary tract issue. So the first question should determine when the last menstrual period occurred to assess whether the sample could be contaminated. If menses are or recently were occurring, plan a repeat clean-catch urine sample away from menses to confirm whether true microscopic hematuria is present. If the sample isn’t associated with menses, then you’d pursue further evaluation for true hematuria as indicated. While questions about sexual activity, medications, or recent fever can be relevant later, they don’t directly address the likelihood of contamination and misinterpretation of the current urine result.

Contamination from menstrual blood is the most common pitfall when interpreting a urinalysis in a teenage girl. A sample collected around the time of a period can show red blood cells on microscopy or appear positive for blood on the dipstick, even if there isn’t a urinary tract issue. So the first question should determine when the last menstrual period occurred to assess whether the sample could be contaminated. If menses are or recently were occurring, plan a repeat clean-catch urine sample away from menses to confirm whether true microscopic hematuria is present. If the sample isn’t associated with menses, then you’d pursue further evaluation for true hematuria as indicated. While questions about sexual activity, medications, or recent fever can be relevant later, they don’t directly address the likelihood of contamination and misinterpretation of the current urine result.