MADRID – A late diagnosis of chronic kidney disease is cause for concern. Scientific societies are therefore advocating for screening at younger ages to reverse this trend and slow the progression of the disease. Nearly all patients seen in primary care are candidates for screening because of their risk factors for kidney disease.
During the 29th National Conference of General and Family Medicine of the Spanish Society for General and Family Physicians, Teresa Benedito, MD, family doctor and member of the society’s cardiovascular group, and Roberto Alcázar, MD, nephrologist at the Infanta Leonor University Hospital, Madrid, presented a clinical case encountered in primary care. They used this case to frame a strong argument for the importance of early screening for chronic kidney disease, and they discussed how to properly manage such screening.
The presentation followed the guidelines in the SEMG publication regarding the management and referral of patients with type 2 diabetes. Dr. Benedito explained that the first thing to ask oneself during a patient visit is “whether they present risk factors for kidney disease. If so, we can’t let them leave before we do a kidney screening.” She then listed the factors in question: age older than 60 years, African heritage, family history of chronic kidney disease, decreased kidney mass, weight loss at birth, hypertension, diabetes, smoking, obesity, and low socioeconomic status.
For his part, Dr. Alcázar mentioned how these factors are similar to cardiovascular risk factors, because “the kidneys are a ball of vessels with double capillarization for purifying blood. They’re the organs with the most arteries per unit of weight, so anything that can damage the arteries can damage the kidneys.”
Candidates for screening
“Chronic kidney disease develops in 15% of the adult population in Spain. So, it’s worth asking how many patients have been diagnosed and who should we should be screening.” To the factors listed above, Dr. Alcázar added treatment with nephrotoxic drugs (including nonsteroidal anti-inflammatory drugs) for patients with obstructive urinary tract disease, and a history of acute kidney injury for patients with chronic autoimmune disease or neoplasms. “Thus, nearly all patients seen in primary care would need to be screened.”
Another fundamental question raised was whether patients should be screened before age 60 years. “As a nephrologist, I feel that we have been diagnosing chronic kidney disease late, even though we’ve been doing everything by the book,” said Dr. Alcázar. In his opinion, “the answer to whether we should be screening earlier ... is yes, for two reasons: first, because it’s cost-effective, and second, because it’s very inexpensive.”
Dr. Benedito explained in detail the process for diagnosing this disease. She began by defining the disease as changes in kidney structure and function that last longer than 3 months. These changes are identified by use of two criteria: glomerular filtration rate less than 60 mL/min and kidney injury or lesions with or without reduced filtration rate (renal biopsy, albumin/creatinine ratio greater than 30 mg/g, proteinuria, alterations in urinary sediment or in imaging tests). Thus, “if one of these two criteria persists for more than 3 months, the diagnosis is chronic kidney disease. Also, high creatinine levels are not diagnostic for the disease,” she emphasized.