What are the initial labs and imaging for a patient with suprapubic (above the pubic bone) pain and nausea for one week?

From the Guidelines

For a patient with suprapubic pain and nausea for one week, the initial workup should include urinalysis, complete blood count (CBC), comprehensive metabolic panel (CMP), and urinary pregnancy test for females of reproductive age, followed by imaging with a pelvic ultrasound as the first-line choice, which can be complemented with CT Abdomen and Pelvis With IV Contrast if initial findings are inconclusive or if a life-threatening diagnosis is suspected, as recommended by the most recent guidelines 1.

When evaluating a patient with suprapubic pain and nausea, it's crucial to consider a broad range of potential causes, including urinary, gynecologic, and intestinal pathologies. The initial laboratory tests such as urinalysis, CBC, and CMP are essential for identifying signs of infection, inflammation, or electrolyte imbalances that could point towards specific diagnoses like urinary tract infections, kidney stones, or appendicitis.

• The CBC can help detect infection or inflammation through elevated white blood cells.
• The CMP assesses kidney function and electrolyte balance, which is vital for patients presenting with nausea and suprapubic pain.
• A urinary pregnancy test is critical for females of reproductive age to rule out ectopic pregnancy or other pregnancy-related complications.

Imaging plays a pivotal role in the diagnosis, with pelvic ultrasound being the preferred initial imaging modality due to its non-invasive nature and ability to identify a variety of pathologies, including ovarian cysts, pelvic inflammatory disease, and intestinal issues. However, CT Abdomen and Pelvis With IV Contrast may be considered if the initial ultrasound is inconclusive or if there's a suspicion of a life-threatening condition, as it can provide detailed images of the abdominal and pelvic organs, helping to diagnose conditions such as adnexal torsion, tubo-ovarian abscess, or complications related to endometriosis, with a sensitivity of 74% to 95% and a specificity of 80% to 90% for adnexal torsion 1.

The choice of imaging should be guided by the clinical presentation and the findings of the initial laboratory tests, always keeping in mind the principle of minimizing radiation exposure, especially in younger patients. The recent update from the American College of Radiology Appropriateness Criteria supports the use of CT abdomen and pelvis with IV contrast in specific scenarios where initial imaging is inconclusive or when life-threatening diagnoses are considered 1.

From the Research

Initial Evaluation

For a patient presenting with suprapubic pain and nausea for one week, the initial evaluation should include:

• A thorough medical history to identify potential causes of the symptoms
• Physical examination to assess for signs of infection, inflammation, or other conditions
• Laboratory tests to help diagnose the underlying cause of the symptoms

Laboratory Tests

The following laboratory tests may be ordered:

• Urinalysis to check for signs of urinary tract infection (UTI), such as leukocyte esterase, nitrite, and blood in the urine 2, 3
• Urine culture to confirm the presence of a UTI and guide antibiotic treatment 4
• Complete blood count (CBC) to check for signs of infection or inflammation
• Blood chemistry tests to evaluate kidney function and check for other potential causes of the symptoms

Imaging Studies

Imaging studies may be ordered to further evaluate the cause of the symptoms, such as:

• Ultrasound of the kidneys and bladder to check for signs of infection, obstruction, or other conditions
• Computed tomography (CT) scan of the abdomen and pelvis to evaluate the kidneys, bladder, and surrounding tissues

Diagnostic Approach

The diagnostic approach should be guided by the patient's symptoms, medical history, and laboratory test results. For example:

• If the patient has a positive urinalysis and symptoms consistent with a UTI, antibiotic treatment may be initiated without further testing 2, 4
• If the patient has persistent or severe symptoms, further testing such as imaging studies or specialty consultation may be necessary to rule out other conditions 4