A study coming out in the November issue of the Clinical Journal of the American Society of Nephrology is reporting that type 2 men whose blood contained a high count of eosinophils, a sign of allergic inflammation, also had albumin in their urine, which is an early indication of kidney disease. Eosinophils are white blood cells that increase in number during an allergic reaction. Albumin is a protein in the blood that helps regulate blood volume and acts as a carrier for other molecules. Albumin is not normally found in the urine, however, because when healthy kidneys filter the blood, they retain what the body needs (like proteins) and allow only smaller "impurities" into the urine. But during diabetes, too much blood sugar can damage the filtering structures of the kidneys, causing them to thicken and become scarred. Eventually, they begin to leak, and protein (albumin) begins to pass into the urine.

Michiaki Fukui, MD, of the Kyoto Prefectural University of Medicine in Japan, and his colleagues were surprised to find that the connection between the eosinophil count and the albumin excretion rate was even stronger than the connection between albumin excretion and other risk factors like high blood pressure and poor diabetes control. However, the eosinophil count did not correlate to albumin excretion in women with diabetes.

The study can't prove a cause-and-effect relationship between eosinophil count and albumin excretion rate. More research will be needed to determine why the relationship was found only in men, and whether a similar link is also present in patients without diabetes.

The idea of a connection between these two findings is interesting in that some of the anti-inflammatory treatments used by patients with allergies can lower the eosinophil count, and it's possible that these treatments could also benefit male patients with diabetes, Fukui believes. Speaking to EurekAlert, he noted that "the intriguing concept of a role for eosinophils in diabetic nephropathy holds great promise for the development of new preventive measures involving anti-allergic agents."

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Sources: 

Mayo Clinic

Medline Plus

EurekAlert