What tests are included in a complete panel for a patient?

Complete Panel Testing for Patient Evaluation

A complete panel for a patient consists of a complete blood count (CBC) with differential and a comprehensive metabolic panel (CMP), which together provide essential baseline information about hematologic, renal, hepatic, and metabolic function. 1

Core Components

Complete Blood Count (CBC) with Differential

The CBC with differential white blood cell count should be obtained upon initiation of care and includes: 1

• Total white blood cell count with differential - identifies anemia, leukopenia, thrombocytopenia, and abnormal cell populations 1
• Hemoglobin and hematocrit - assesses for anemia, which is common in many disease states 1
• Platelet count - evaluates thrombocytopenia or thrombocytosis 1
• Red blood cell indices (MCV, MCH, MCHC) - characterizes type of anemia if present 2
• Peripheral blood smear review - essential when abnormalities are detected to assess for dysplasia, blasts, or other morphologic changes 1

The CBC is critical because it calculates the total CD4 cell count in immunocompromised patients and provides baseline data before initiating medications with myelosuppressive effects. 1

Comprehensive Metabolic Panel (CMP)

The chemistry panel is an essential tool to assess renal and hepatic function and includes: 1, 3

• Electrolytes: sodium, potassium, chloride, carbon dioxide (bicarbonate) 3
• Kidney function markers: blood urea nitrogen (BUN) and creatinine 1, 3
• Liver function tests: albumin, total protein, alkaline phosphatase, ALT, AST, total bilirubin 1, 3
• Glucose - screens for glucose intolerance and diabetes 1, 3
• Calcium - detects hypercalcemia or hypocalcemia 1, 3

The CMP provides baseline information necessary before initiating therapeutic agents that may have nephrotoxic or hepatotoxic effects, or those requiring dosage adjustment in renal or hepatic dysfunction. 1

Additional Essential Tests Based on Clinical Context

Fasting Metabolic Studies

• Fasting lipid profile (total cholesterol, LDL, HDL, triglycerides) should be obtained upon initiation of care, as many conditions and medications affect lipid metabolism 1
• Fasting glucose and/or hemoglobin A1c (HbA1c) - recommended to screen for glucose intolerance and diabetes, especially given increased prevalence in many patient populations 1

Coagulation Assessment

When coagulopathy is suspected, additional testing includes: 4

• Prothrombin time (PT/INR) and activated partial thromboplastin time (aPTT) - evaluates coagulation pathways 4
• Disseminated intravascular coagulation panel including D-dimer, fibrinogen, PT, and aPTT when clinically indicated 1

Prognostic and Specialized Markers

• Lactate dehydrogenase (LDH) - critical prognostic marker for lymphoma, hemolysis, and tissue damage 1, 4
• Uric acid - part of tumor lysis syndrome panel when malignancy suspected 1
• Serum protein electrophoresis (SPEP) - evaluates for paraproteinemia when monoclonal gammopathy suspected 1
• Quantitative immunoglobulins - assesses immune function and detects monoclonal proteins 1

Clinical Utility and Timing

The complete panel provides baseline information that is necessary before initiating therapeutic agents and allows monitoring for drug-related toxicities. 1 These tests should be performed at initial evaluation and repeated as clinically indicated based on:

• Disease progression or treatment response 1
• Medication changes, particularly those with known hematologic, renal, or hepatic toxicity 1
• Development of new symptoms or complications 1

Common Pitfalls to Avoid

• Failing to obtain fasting samples when lipid profile or glucose assessment is needed - nonfasting values may be misleading, though in young children fasting studies are more problematic and nonfasting levels can be obtained first 1
• Not reviewing the peripheral blood smear when CBC abnormalities are present - morphologic examination is essential for proper interpretation 1
• Overlooking the need for additional specialized testing when initial panel results are abnormal - bone marrow evaluation, flow cytometry, or molecular testing may be necessary 1, 4
• Ordering unnecessary tests without clinical indication - the complete panel should be tailored based on clinical presentation, though CBC and CMP form the essential core 1