What further imaging and laboratory tests are indicated at this time?

Recommended Imaging and Laboratory Tests

For patients with suspected disease requiring further evaluation, a comprehensive workup should include CT or MRI of the abdomen and pelvis, chest imaging, and laboratory studies including complete blood count, chemistry panel, and specific disease markers based on clinical presentation. 1

Imaging Recommendations

Initial Imaging Studies

• CT scan with contrast of abdomen and pelvis: First-line imaging study for most conditions due to its wide availability, accuracy, and detailed anatomic information 1
• Chest X-ray or CT: Essential to rule out mediastinal masses, pleural effusion, or pulmonary involvement 1
• MRI with gadolinium: Alternative when CT contrast is contraindicated or for better soft tissue characterization 1

Condition-Specific Imaging

• For suspected aortic disease: CT is the preferred initial diagnostic imaging modality due to its wide availability, accuracy, speed, and anatomic detail 1
• For suspected malignancy: Consider whole-body PET/CT if lymphoblastic lymphoma is suspected 1
• For suspected valvular heart disease: Echocardiogram for assessment of left ventricular function, especially if anthracycline therapy is planned 1

Laboratory Studies

Basic Laboratory Panel

• Complete blood count (CBC) with differential and platelets 1
• Comprehensive metabolic panel including:
  • Liver function tests
  • Renal function tests
  • Electrolytes
  • Calcium, phosphorus 1

Disease-Specific Laboratory Tests

• Tumor lysis syndrome panel: Lactate dehydrogenase (LDH), uric acid, potassium, calcium, phosphorus 1
• Coagulation studies: D-dimer, fibrinogen, prothrombin time (PT), partial thromboplastin time (PTT) 1
• For suspected cardiac involvement: Cardiac biomarkers and assessment of left ventricular function 1

Special Considerations

For Suspected Malignancy

• Bone marrow evaluation may be necessary for suspected hematologic malignancies
• Lumbar puncture with CSF analysis if neurologic symptoms are present or CNS involvement is suspected 1
• Fertility preservation considerations should be addressed before initiating treatments that may affect fertility 1

For Suspected Aortic Disease

• Measure blood pressure in both arms and lower extremities to detect pressure differentials 1
• D-dimer testing may help exclude aortic dissection in low-risk patients 1

Algorithmic Approach to Further Testing

1. Identify primary organ system involvement based on presenting symptoms
2. Obtain appropriate cross-sectional imaging (CT or MRI) of the involved area
3. Perform targeted laboratory testing based on suspected diagnosis
4. Consider specialized testing based on initial results:
   • For renal masses: Consider renal ultrasound or CT urogram 1
   • For cardiac abnormalities: Echocardiogram or cardiac MRI 1
   • For suspected genetic disorders: Consider genetic testing 1

Common Pitfalls to Avoid

• Overreliance on laboratory screening without clinical correlation can lead to unnecessary follow-up testing 2
• Inadequate imaging protocols that fail to capture the full extent of disease 1
• Failure to consider patient-specific factors such as radiation exposure, contrast allergies, or renal function when selecting imaging modalities
• Missing surveillance opportunities for patients with established disease who require regular monitoring 1

By following this structured approach to further imaging and laboratory testing, clinicians can efficiently diagnose and monitor patients while minimizing unnecessary testing and radiation exposure.