Who Should Get Routine Labs?

If you have chronic diseases, such as high blood pressure or diabetes (among others), you should have your blood work checked every 3-6 months. If well controlled, 6 months is acceptable, but if not, then every 3 months would be better. Both of these conditions are accompanied by another chronic disease called chronic kidney disease. Many patients are surprised to see this in their records and are startled by the scary connotations associated with it's name.

Fear not! Anyone who has a condition that increases their risk of kidney damage (such as high blood pressure, diabetes, polycystic kidney disease, and many others) already has chronic kidney disease. The STAGE of the kidney disease is what one needs to know. Without having any blood work or urine tests to check for protein in the urine, staging cannot be performed. The following indicates the stages of chronic kidney disease:

• Stage 1 - Normal GFR (glomerular filtration rate) on blood work and a normal urine microalbumin to creatinine ratio (no protein leaking from the kidneys). A normal GFR if greater than 90; however, many labs cannot accurately calculate this level and simply note a normal level as being above 60, which is perfectly fine since it does not change management.

  
  

• Stage 2 - Normal GFR on blood work (but generally 60-89) with a urine microalbumin to creatinine ratio greater than 30 or a urine sample that shows protein in the urine. The urine testing should be when one is well and not when a urinary tract infection is present since that alone can cause protein in the urine. Women should also not be on their menstrual cycle when collecting as this can create a false positive as well.

  
  

• Stage 3 - Decreased GFR between 30-59 +/- protein in the urine. This is the stage when the kidney becomes impaired to the point that it cannot make hormones normally. Conversion of vitamin D into it's active form occurs in the kidneys. Because of this, vitamin D levels will drop and continue to drop unless supplements are taken. Not all supplements are created equal. Also, the bone marrow may not produce red blood cells normally which can lead to anemia. This can cause one to feel tired/weak. Injections of a hormone produced by the kidney, erythropoietin (EPO), are needed if your hemoglobin drops below 10. One must have enough iron stores for EPO to work properly so iron studies need to be monitored. If you have CKD Stage 3 and anemia, you should be seeing a kidney doctor. You can ask your provider for a referral at anytime. They will either address these issues themselves or refer you to a nephrologist. I have found that even though I can manage these conditions myself, special medications such as EPO are covered better by insurance if prescribed by a specialist.

  • Stage 3a - GFR 45-59 indicating a mild to moderate loss of kidney function

  • Stage 3b - GFR 30-44 indicating moderate to severe loss of kidney function

    
    

• Stage 4 - Decreased GFR 15-29 +/- protein in the urine. This stage indicates severe loss of kidney function and is the stage when you should be seeing a kidney doctor (Nephrologist) since this is the stage just before "End Stage" and when one must decide whether they want to start dialysis if symptoms of fluid overload develop and cannot be controlled with water pills (diuretics) or if their potassium levels cannot be controlled with diet modifications and medications.

  
  

• Stage 5 - End stage chronic kidney disease or kidney failure with a GFR less than 15. At this stage, your kidneys are not functioning normally and cannot rid the body of normal electrolytes, medications, toxins, or even water! Because of this, potassium levels can become very elevated and lead to irregular heart rhythms which can cause the heart to stop, excess water will cause swelling throughout the body including visible places like the legs, hands, and face as well as other places like the abdomen (causing abdominal pain, nausea, and bloating) and lungs (causing shortness of breath either at rest or with activity, an inability to lie flat due to worsening shortness of breath). Anyone with CKD and edema should be on a water pill (diuretic) to limit excess water from accumulating in the body. These medications cause frequent urination and electrolyte abnormalities such as low potassium since it is flushed from the body when the water leaves. More frequent lab monitoring is needed at this stage in addition to self monitoring of weight, blood pressure, and symptoms.

To answer the original question of who should get labs, consider getting annual labs starting at age 40 such as a CBC (complete blood count) to ensure normal blood counts and CMP (comprehensive metabolic panel) that checks your electrolytes, kidney function, and liver function at least once a year if you are healthy and have no symptoms. If you are younger and have symptoms such as no energy, dizziness, abdominal pain, nausea, or other symptoms, you should get at least these labs checked and see a provider for further evaluation as you may need others as well including urine tests. These would not be considered routine tests. If you have chronic diseases such as high blood pressure, diabetes, or CKD you should have them checked every 3 months.

Cholesterol should be checked once starting at age 21 (or sooner in some with genetic conditions). If normal at that time, it can be checked every 5 years.

Men have the option of checking a screening PSA (prostate test) starting at the age of 40. Screenings are for those without symptoms. If there is a family history of aggressive prostate cancer, I would recommend checking this annually even if no symptoms are present. If symptoms are present, even in younger men, such as changes in urination then a diagnostic PSA should be checked. Prostatitis can cause an elevated PSA as well and is treated with antibiotics for 2 weeks if a recent infection though some can have chronic prostatitis that requires up to 4 weeks of antibiotics. It can be scary thinking you have prostate cancer when an infection may be the cause of the abnormal test so seeing a provider to help evaluate you is very important if this test returns elevated.

Diabetics: Typical labs checked every 3 months include CBC, CMP, A1c. Labs checked once a year include TSH, LIPID panel, urine protein.

Those with high BP: Consider CBC, CMP every 3-6 months. Once a year, check LIPID panel. At initial diagnosis, other tests may need to be performed to rule out secondary causes.

There are multiple other reasons to have labs checked; however, medical guidance is recommended, especially if you have abnormal results.