Does a glomerular cause of renal disease always present with proteinuria or hematuria?

From the Guidelines

No, glomerular causes of renal disease do not always present with proteinuria or hematuria, although these are common findings. While proteinuria and hematuria are hallmark signs of glomerular damage, some glomerular diseases may be subclinical or in early stages where these manifestations are not yet detectable by routine testing. For example, early diabetic nephropathy may have minimal proteinuria below the detection threshold of standard dipstick tests, requiring more sensitive albumin-to-creatinine ratio measurements. Similarly, some forms of focal segmental glomerulosclerosis or membranous nephropathy may initially present with minimal or intermittent proteinuria. Hematuria can also be absent in certain glomerular conditions or may be intermittent, making it possible to miss during testing. Additionally, the sensitivity of testing methods matters - microscopic hematuria might be present but not detected with less sensitive methods.

Key Points to Consider

• The presence of significant proteinuria, red cell casts, or renal insufficiency should prompt an evaluation for renal parenchymal disease 1.
• Patients with microscopic hematuria and no evidence of glomerular bleeding are considered to have isolated hematuria, but still require follow-up for the development of hypertension, renal insufficiency, or proteinuria 1.
• The kidney biopsy is the gold standard for diagnostic evaluation of glomerular diseases and should be performed if the biopsy result is expected to modify treatment and/or if additional prognostic information is needed 1.
• A patient-centered discussion on the utility of a kidney biopsy for definitive diagnosis is necessary for patients with preserved eGFR, lower levels of proteinuria, and a low suspicion for other glomerular disorders 1. Therefore, while the absence of proteinuria and hematuria makes glomerular disease less likely, it does not definitively rule it out, especially in early or mild cases. The most recent guideline recommends a kidney biopsy if it is expected to modify treatment or provide additional prognostic information 1.

From the Research

Glomerular Disease and Renal Impairment

• Glomerular disease is a complex and evolving topic, and its diagnosis can be challenging 2.
• The presence of urinary abnormalities, such as proteinuria and haematuria, is a key feature of glomerulonephritis 3.
• However, not all patients with glomerular disease may present with proteinuria or haematuria, as the disease can manifest in different ways.

Diagnostic Approaches

• Diagnostic algorithms based on quantitative measures can help navigate the diagnosis of glomerular disease 2.
• The use of biomarkers, such as the urinary albumin-to-total-protein ratio, can help differentiate between glomerular and nonglomerular bleeding 4.
• Plasma and urine biomarkers, such as kidney injury molecule-1 and monocyte chemoattractant protein-1, can also be used to characterize CKD and predict progression 5.

Clinical Implications

• Timely diagnosis and treatment of glomerulonephritis are essential to minimize complications and slow disease progression 3.
• Patients with glomerulonephritis should be managed according to CKD guidelines, with regular measurement of renal function, blood pressure, and proteinuria 3.
• The treatment of glomerulonephritis should be individualized and may involve a combination of symptomatic treatment, angiotensin-converting enzyme inhibitors, and immunosuppressive therapy 6.