From the Guidelines
Elevated protein levels in the blood, or hyperproteinemia, are most commonly caused by dehydration, infections or inflammation, certain cancers, liver diseases, and autoimmune disorders, with kidney diseases also playing a significant role in altering protein levels and metabolism. When considering the causes of hyperproteinemia, it's essential to evaluate the patient's overall health and potential underlying conditions. Dehydration concentrates proteins in the bloodstream, while infections or inflammation trigger increased production of antibodies and other immune proteins [ 1 ]. Certain cancers like multiple myeloma or lymphoma cause overproduction of immunoglobulins, and liver diseases such as cirrhosis alter protein metabolism [ 1 ]. Autoimmune disorders like lupus or rheumatoid arthritis stimulate antibody production, and kidney diseases can elevate protein levels in the blood while causing protein to appear in urine. Some key points to consider when evaluating hyperproteinemia include:
- Dehydration can be addressed by increasing fluid intake to normalize protein levels
- Infections require appropriate antibiotics or antivirals
- Cancer-related protein elevations need oncology treatment
- Autoimmune conditions typically require immunosuppressive medications
- Elevated proteins often serve as important diagnostic markers, reflecting the body's response to disease processes through increased production of antibodies, inflammatory mediators, or abnormal proteins [ 1 ]. In terms of specific conditions, liver diseases such as nonalcoholic fatty liver disease (NAFLD) and alcohol-induced liver disease are common causes of mild increases in aminotransferases, which can be associated with hyperproteinemia [ 1 ]. The AST:ALT ratio can help differentiate between alcohol-induced fatty liver disease and metabolic disease-related fatty liver, with a ratio generally >2 in alcohol-induced fatty liver disease and <1 in metabolic disease-related fatty liver [ 1 ]. Overall, a comprehensive evaluation of the patient's health and underlying conditions is necessary to determine the cause of hyperproteinemia and develop an effective treatment plan.
From the Research
Causes of Elevated Protein Levels
Elevated protein levels, specifically hyperproteinemia, can be caused by various factors. Some of the possible causes include:
- Liver diseases, such as hepatocellular carcinoma (HCC) 2
- Chronic kidney disease (CKD), which can lead to increased urine protein excretion 3
- Inflammation, as indicated by elevated C-reactive protein (CRP) levels, which can be associated with an increased risk of chronic kidney disease (CKD) 4
- Cancer, as elevated CRP levels have been linked to an increased risk of certain types of cancer, such as lung cancer 5
- Metabolic dysfunction-associated steatotic liver disease (MASLD) and alcoholic liver disease, which are common causes of mildly elevated liver transaminase levels 6
Associated Conditions
Hyperproteinemia can be associated with various conditions, including:
- Hepatocellular damage, as reflected by elevated alanine aminotransferase levels 2
- Kidney damage, as indicated by decreased glomerular filtration rate (GFR) and increased urine albumin excretion 3
- Inflammatory processes, as evidenced by elevated CRP levels 4, 5
- Liver disease, as suggested by elevated liver transaminase levels 6
Biomarkers
Certain biomarkers can be used to diagnose and monitor hyperproteinemia, including:
- Liver-type fatty acid-binding protein (L-FABP), which can serve as a biomarker for liver diseases 2
- C-reactive protein (CRP), which can indicate inflammation and be associated with an increased risk of CKD and cancer 4, 5
- Urine albumin excretion and urine protein excretion, which can be used to monitor kidney function and detect kidney damage 3