What is the clinical interpretation of a patient with normal complete blood count (CBC), normal urinalysis, normal vitamin B12, normal folate, and low prostate-specific antigen (PSA) levels?

Clinical Interpretation of Laboratory Results

These laboratory results are entirely reassuring and indicate no acute pathology requiring intervention. The patient demonstrates normal hematologic function, no evidence of urinary tract disease, adequate nutritional status, and a low prostate cancer risk profile.

Complete Blood Count Analysis

The CBC reveals mild microcytosis without anemia, which is clinically insignificant in this context.

• Hemoglobin (14.6 g/dL) and hematocrit (45.0%) are normal, excluding anemia as a concern 1
• MCV of 79.8 fL indicates mild microcytosis (normal range typically 80-100 fL), but this is not accompanied by anemia 1
• MCH (25.9 pg) and MCHC (32.4 g/dL) are proportionally reduced, consistent with the mild microcytosis 1
• White blood cell count (5.0 K/uL) with normal differential excludes infection, bone marrow dysfunction, or hematologic malignancy 1
• Platelet count (357 K/uL) is normal, indicating adequate bone marrow function 1

The mild microcytosis without anemia typically represents either early iron deficiency, thalassemia trait, or chronic disease. Given normal B12 and folate levels, macrocytic causes are excluded 1. This finding alone does not warrant aggressive investigation in an asymptomatic patient.

Urinalysis Interpretation

The urinalysis is completely normal, effectively excluding urinary tract infection, hematuria, proteinuria, and bladder pathology.

• Negative leukocyte esterase and nitrites with no WBCs exclude urinary tract infection 1
• Negative occult blood with no RBCs exclude hematuria from bladder cancer, stones, or infection 1
• Negative protein excludes significant renal disease 1
• No bacteria or casts further confirm absence of infection or renal pathology 1

According to AUA guidelines, a normal urinalysis makes bladder cancer, carcinoma in situ, urethral strictures, and bladder stones significantly less likely in men presenting with lower urinary tract symptoms 1.

Vitamin B12 and Folate Assessment

Both vitamin B12 (321 pg/mL) and folate (5.9 ng/mL) are within normal ranges, excluding deficiency states.

• Vitamin B12 of 321 pg/mL is adequate (normal typically >200 pg/mL), excluding megaloblastic anemia and neurologic complications of B12 deficiency 2
• Folate of 5.9 ng/mL is borderline but acceptable (normal >5 nmol/L), though borderline folate (5-7 nmol/L) with elevated homocysteine would indicate high risk of deficiency 2
• The normal CBC with normochromic indices confirms functional adequacy of these vitamins 1

These levels exclude vitamin deficiency as a cause of the mild microcytosis observed 1, 3.

Prostate-Specific Antigen Interpretation

A PSA of 0.60 ng/mL is exceptionally low and indicates minimal prostate cancer risk.

• PSA <1.0 ng/mL at baseline is associated with <0.3% lifetime risk of prostate cancer death, according to NCCN guidelines 1
• This level is well below the 2.5-4.0 ng/mL threshold where prostate biopsy consideration begins 1, 4
• Men with PSA <1.0 ng/mL require less intensive screening, as 90% of prostate cancer deaths occur in men in the top 10% for PSA 1
• The low PSA also suggests minimal benign prostatic hyperplasia, as PSA correlates with prostate tissue volume 1, 5

This patient can be reassured that prostate cancer risk is extremely low, and routine PSA screening intervals can be extended 1.

Clinical Significance and Management

No immediate intervention is required based on these laboratory results.

For the Mild Microcytosis:

• Consider iron studies (ferritin, TIBC, serum iron) if clinically indicated by symptoms of fatigue or if the patient has risk factors for iron deficiency 1
• Hemoglobin electrophoresis may be considered if family history or ethnicity suggests thalassemia trait 1
• Repeat CBC in 6-12 months to assess for progression toward anemia 1

For Prostate Health:

• Repeat PSA screening can be deferred for 2-4 years given the exceptionally low baseline value 1
• Digital rectal examination should still be performed as part of routine physical examination if the patient has lower urinary tract symptoms 1

Common Pitfalls to Avoid:

• Do not over-investigate mild microcytosis without anemia in asymptomatic patients—this often represents normal variation or thalassemia trait 1
• Do not assume low PSA excludes all urologic pathology—bladder cancer and urethral strictures can occur with normal PSA 1
• Do not interpret borderline folate (5.9 ng/mL) as deficiency without measuring homocysteine or methylmalonic acid if clinical suspicion exists 2