The consequence of low blood protein depends on how low the protein becomes, which protein is low, and the cause of the low protein. Having a correct level of protein in the blood is essential for life. Each protein has specific functions. Some of these proteins like albumin are vital for maintaining blood volume and transporting other substances. Other proteins are involved with the immune system and some with blood clotting. Still others are part of a group of signaling proteins that aid communication between cells. Many, but not all, of the blood proteins are made in the liver.

Albumin is the most abundant protein. It helps keep fluid in the blood vessels. When albumin becomes too low, fluid is not properly pulled back into the bloodstream from the tissues. This can result in fluid buildup in the tissues, abdomen, and chest. If severe, depending on where the fluid has built up, there may be difficulty breathing, the abdomen can be distended, vomiting and diarrhea can occur, and the limbs can become swollen.

There are many reasons why blood protein levels can become low, ranging from inadequate diet, intestinal disease, liver disease, or kidney disease with protein loss into the urine.

Therapy is directed at controlling the consequence of the low protein like draining excess fluid from the chest or abdomen if needed. Additional therapy is determined by identifying the cause of the low protein. This involves a complete evaluation including the history of the problem, reviewing the regular diet, performing a physical examination, and running specific diagnostic tests. Diagnostic testing could include blood and urine tests, radiographs, ultrasound and even biopsies if indicated.

One place that protein can be lost is the kidney (protein losing nephropathy). The kidney has multiple functions including filtering the blood, influencing blood pressure, regulating fluid and body acid-base balance, red blood cell production, and converting vitamin D to its active form. These functions are vital for maintaining health.

During the blood filtration process large proteins are not allowed to pass into the urine normally. When the kidney filtration barrier is damaged, protein can leak into the urine. However, it is important to note that not all protein in urine is caused by leakage through the filtration process. Other causes for protein in the urine that are not leakage from the kidney include urinary tract infections, inflammation in the urinary bladder caused by stones, and issues with the reproductive tract.

Long term diets high in protein don’t cause increase urine protein but may contribute to increased stress on the kidney that weakens its normal function over time. Other problems that contribute to kidney stress and protein leakage include metabolic diseases, hypertension, inflammatory conditions like pancreatitis and infectious problems like tick borne diseases, and cancer.

It should be clear that simply finding protein in the urine does not give a complete picture. The source of the problem needs to be identified so that appropriate steps can be taken. Keep in mind that some causes of increased urine protein associated with the kidney are transient, therefore, depending on the complete situation with the pet, the recommendation may be to repeat the urine test in 2-3 weeks to see if the problem is still present.

Therapy is dependent on the final diagnosis and identification of the cause of protein loss through the kidney. This may include specific diet changes, medication for managing blood pressure, anti-inflammatory drugs, and fluid removal from body cavities.

Integrative support therapies include fish oil which contains omega 3 fatty acids that are considered anti-inflammatory and may have kidney protective properties that can decrease the progression of kidney failure. Kidney extracts containing bioactive factors that are specific for kidneys that may help the kidney meet its increased need for these factors during times of functional stress. Adaptogen herbs like astragalus (Astragalus membranaceus) and mushrooms like reishi (Ganoderma lucidum) can support kidney function by improving blood flow and reducing proteinuria. They also have properties that aid the body’s ability to address stress. Acupuncture and manual therapies tailored to the individual needs of the pet can enhance the benefits of the overall support plan.

If you have a pet that you suspect has a kidney or other health problem, contact your veterinarian.

Ron Carsten, DVM, PhD, CVA, CCRT was one of the first veterinarians in Colorado to use the integrative approach, has lectured widely to veterinarians, and has been a pioneer in the therapeutic use of food concentrates to manage clinical problems. He is also the founder of Colorado Animal Rescue (CARE). In addition to his Doctor of Veterinary Medicine, he holds a PhD in Cell and Molecular Biology and is a Certified Veterinary Acupuncturist and Certified Canine Rehabilitation Therapist. He practices integrative veterinary medicine in Glenwood Springs. Dr. Carsten is the 2022 Colorado Veterinary Medical Association Distinguished Service Award recipient.