Laboratory Testing Recommendations
Yes, order both a CBC and BMP as part of your initial laboratory evaluation, as these tests provide essential baseline information for assessing multiple organ systems, detecting common metabolic and hematologic abnormalities, and guiding further diagnostic workup. 1, 2
When to Order CBC and BMP Together
Standard Clinical Scenarios Requiring Both Tests
Initial evaluation of suspected metabolic disorders or systemic illness requires a comprehensive metabolic panel (which includes BMP components) plus CBC to assess for anemia, infection, or hematologic disorders 1, 2
Diabetes management specifically requires BMP for glucose and electrolyte monitoring, with CBC recommended annually to screen for complications 1
Suspected renal malignancy or renal mass evaluation mandates both comprehensive metabolic panel (including BMP components) and CBC as part of the standard workup 1
Vascular cognitive impairment or stroke evaluation requires CBC, TSH, B12, calcium, electrolytes (BMP), creatinine, ALT, lipid panel, and HbA1c 1
Weakness evaluation necessitates both comprehensive metabolic panel and CBC with differential as the initial laboratory assessment 2
Disease-Specific Indications
Cancer workup (including renal cell carcinoma and myeloproliferative neoplasms) requires comprehensive metabolic panel for metabolic assessment and CBC for hematologic evaluation 3
Congenital syphilis evaluation in older infants and children requires CBC with differential and platelet count plus metabolic assessment 1
Before initiating DMARDs in suspected juvenile idiopathic arthritis, obtain liver and renal function tests (BMP components) as baseline monitoring 4
Clinical Utility of Each Test
BMP Components Provide
Kidney function assessment through creatinine and blood urea nitrogen 1
Electrolyte status including sodium, potassium, chloride, and carbon dioxide 1, 3
Glucose monitoring for diabetes screening and management 1, 3
Calcium levels for metabolic assessment 1
CBC Components Provide
Anemia detection through red blood cell count, hemoglobin, and hematocrit 5, 6, 7
Infection screening via white blood cell count with differential 2, 6
Hematologic disorder identification including thrombocytopenia or thrombocytosis through platelet count 5, 6
Cardiovascular and metabolic disease risk assessment using neutrophil-to-lymphocyte ratio, red cell distribution width, and mean platelet volume 8
Important Caveats
BMP vs CMP distinction: A comprehensive metabolic panel includes all BMP components plus liver function tests (ALT, AST, total bilirubin, albumin, total protein); order CMP instead of BMP when liver function assessment is needed 3
Lipid panel is separate: Neither BMP nor CMP includes lipid testing; order a fasting lipid profile separately if cardiovascular risk assessment is needed 3
Timing considerations: For diabetes patients, if A1C results are not available within the past 3 months, order it along with CBC and BMP 1
Frequency of monitoring: In patients with chronic kidney disease or on medications affecting kidney function (ACE inhibitors, ARBs, diuretics), BMP may need to be checked more frequently than annually 1