What is the possible diagnosis for a female with vaginal itching, dysuria, and urinalysis results indicating proteinuria, hematuria, and alkaline pH?

Possible Diagnosis: Vulvovaginal Candidiasis (Vaginal Yeast Infection)

The most likely diagnosis is vulvovaginal candidiasis (vaginal yeast infection), not a urinary tract infection, based on the predominant vaginal symptoms (itching, burning, irritation) combined with negative leukocyte esterase and nitrites on urinalysis. 1, 2

Key Diagnostic Reasoning

Why This Is NOT a UTI

• Negative leukocyte esterase and nitrites effectively rule out UTI in this symptomatic patient, as these are the most reliable dipstick indicators for bacteriuria requiring therapy 2, 3
• Nitrites have particularly high specificity for UTI, and their absence makes bacterial cystitis unlikely 2
• The absence of pyuria (negative leukocyte esterase) has excellent negative predictive value (91.84%) for ruling out UTI even when symptoms are present 4
• Dysuria in the presence of vaginal irritation has >90% accuracy for a non-UTI cause such as vaginitis 1, 2

Why This IS Vulvovaginal Candidiasis

• The triad of vaginal itching, burning, and dysuria without pyuria is classic for vulvovaginal candidiasis 5, 6
• Vaginal discharge and irritation decrease the probability of UTI (likelihood ratio 0.65) and redirect diagnosis toward vaginitis 7
• Women with vulvovaginal symptoms should be evaluated for vaginitis rather than treated empirically for UTI 6
• Approximately 75% of adult women will experience at least one vaginal yeast infection during their lifetime 5

Urinalysis Findings Explained

The Hematuria and Proteinuria

• Moderate blood (hematuria) and trace protein (30 mg/dL) in a 56-year-old woman require consideration of menstruation as a benign cause 8
• If menstruating, repeat urinalysis 48 hours after cessation of menses is recommended before pursuing urologic workup 8
• Menstruation commonly causes both hematuria and proteinuria that do not require immediate investigation 8

The Alkaline pH

• pH of 8.0 is elevated but nonspecific and can occur with various conditions including specimen contamination, dietary factors, or certain infections 3
• Alkaline urine alone does not establish a diagnosis but should be noted for context 3

Critical Management Algorithm

Immediate Steps

1. Perform pelvic examination to assess for vaginal discharge characteristics (thick, white, cottage cheese-like appearance suggests candidiasis) 5, 6
2. Obtain vaginal pH and wet mount microscopy if available to confirm yeast infection 6
3. Assess menstrual history to determine if hematuria/proteinuria warrant repeat testing 8

Treatment Approach

• If clinical diagnosis of vulvovaginal candidiasis is confirmed, treat with fluconazole 150 mg single oral dose or topical azole therapy 5
• Do NOT treat empirically for UTI given negative leukocyte esterase and nitrites 1, 2, 4

Follow-Up Required

• If patient is menstruating or recently menstruated, repeat urinalysis after menses to reassess hematuria and proteinuria 8
• If hematuria persists on repeat testing (≥3 RBCs per high-power field on microscopy), further evaluation for glomerular or urologic causes is warranted 1, 8
• Cystoscopy and upper tract imaging are NOT routinely indicated for isolated hematuria without risk factors for malignancy 1

Important Caveats

Do Not Overtreat

• Empiric antibiotic treatment based on symptoms alone leads to overtreatment in >50% of cases 4
• Symptoms have low diagnostic accuracy without confirmatory testing, and unnecessary antibiotics contribute to antimicrobial resistance 1, 4

Red Flags That Would Change Management

• Fever, flank pain, or systemic symptoms would suggest pyelonephritis requiring urine culture and different management 1
• Persistent hematuria after excluding menstruation requires evaluation for malignancy, especially with risk factors (age >35, smoking history) 1
• Recurrent symptoms after appropriate treatment warrant urine culture and consideration of complicated infection 1