Which CPT codes should be billed for a new patient presenting with undiagnosed groin pain when a sectoral renal ultrasound and a non‑contrast CT of the abdomen and pelvis are ordered to rule out a kidney stone?

CPT Coding for New Patient with Undiagnosed Groin Pain

For a new patient presenting with undiagnosed groin pain requiring both renal ultrasound and CT to rule out kidney stones, you should bill the following CPT codes:

Office Visit Code

• 99202-99205 (New patient office visit, level 2-5) - Select the appropriate level based on medical decision-making complexity and time spent. Given the need for ordering multiple imaging studies for undiagnosed groin pain, this would typically qualify for at least a 99203 or 99204 level visit.

Imaging Codes

For the Renal/Sectoral Ultrasound:

• 76770 - Ultrasound, retroperitoneal (includes renal), real-time with image documentation; complete
  • OR 76775 if limited to a specific area
  • If Doppler assessment is performed to evaluate for twinkling artifact (which improves sensitivity for small stones), add 93975 or 93976, though note that targeted Doppler for stone detection does not constitute a full Doppler examination 1

For the CT Abdomen and Pelvis:

• 74176 - CT abdomen and pelvis without contrast material (single code for combined study)
  • Important: Since 2011, CT abdomen and pelvis codes have been bundled together 2, 3. You cannot separately bill CT abdomen (74150) and CT pelvis (72192) - this would be incorrect coding and result in claim denial.

Key Coding Considerations:

Noncontrast CT is the appropriate study for suspected kidney stones. The ACR Appropriateness Criteria establish that noncontrast CT is the reference standard for urolithiasis evaluation, with sensitivity as high as 97% 1. Contrast-enhanced CT is not indicated for initial stone evaluation and would be inappropriate coding for this clinical scenario.

Low-dose CT protocols are equally appropriate and maintain 97% sensitivity and 95% specificity for stone detection while reducing radiation exposure 1. The CPT code remains 74176 regardless of dose protocol used.

Documentation requirements:

• Medical necessity must clearly support both imaging studies
• Document why ultrasound alone is insufficient (e.g., need to definitively rule out stones, assess for alternative diagnoses)
• The clinical scenario of "undiagnosed groin pain" may raise questions about ordering both studies simultaneously - ensure documentation explains the clinical reasoning

Common Pitfalls to Avoid:

• Do not bill separate abdomen and pelvis CT codes - this violates bundling rules implemented in 2011 2
• Do not order contrast-enhanced CT for suspected uncomplicated kidney stones - this is not guideline-concordant 1
• Do not bill a complete Doppler exam code if only using targeted Doppler for twinkling artifact assessment 1
• Ensure the ultrasound order specifies "renal" or "retroperitoneal" to support the 76770 code rather than a more limited study