Primary care and nephrology rely largely on routine kidney findings to guide referral and biopsy decisions. However, because these findings are not specific to IgAN and, to date, no validated serum or urine biomarker can confirm the disease, clinicians must determine which abnormalities warrant further investigation and specialist assessment.

Findings from Ipsos’ IgAN Therapy Monitor in the US reflects this diagnostic reality. Nephrologists who took part in this study reported regularly using established measures such as proteinuria and eGFR to support the diagnosis of IgAN, while specialised tests such as Gd-IgA1, serum IgA and complement tests are used less frequently. These tests likely serve different purposes within the diagnostic assessment and cannot currently replace kidney biopsy.

Routine urine and kidney function tests remain the mainstay of assessment, reinforcing that the signal-to-specialist pathway still depends heavily on recognising and appropriately escalating routine kidney abnormalities. Until a validated non-invasive biomarker becomes available, narrowing this gap will depend on making the connection between routine kidney signals and specialist assessment more reliable.