EVALUATION OF ASYMPTOMATIC HAEMATURIA OR PROTEINURIA IN A HIGH RISK POPULATION: IS ULTRASOUND USEFUL?

Abstract

Background: Rates of renal failure in some Aboriginal communities in the Northern Territory are among the highest in the world. Haematuria and proteinuria is also very common but the frequency of structural and parenchymal abnormalities associated with these findings is unclear. Ultrasound examination is common practice for investigation of haematuria/proteinuria. This involves considerable logistic problems and costs for people from remote communities. We conducted a population survey using renal ultrasound in a remote coastal community with high rates of renal disease, to delineate the frequency of abnormal findings.Methods: Urine dipstick analysis and albumin:creatinine ratio (ACR) were measured in people over 5 years old and a detailed renal ultrasound examination performed.Results: Forty percent of the population (n = 664) were included, 286 children aged 5‐18 yr (males 152, females 134) and 377 adults aged 19‐70 yr (males 195 females 182) with a representative sample from all age groups. 11% of children and 10.9% of adults had haematuria ( ≥ 1 + ) and 9.8% of children and 43.8% of adults had proteinuria ( ≥ 1 + ) on urinalysis. Macroalbuminuria (ACR ≥ 34) was present in 21% of adults and 1.4% of children. Microalbuminuria (ACR ≥ 3.4) was present in 49% of adults and in 6.9% of children On ultrasound exam, no abnormal echotexture, medullary abnormalities, poor cortico‐medullary differentiation, marked L/R differ‐ences in size, or dilatation of the collecting system were found. Seven structural abnormalities were identified (2 simple cysts, 1 scar on an upper pole, 1 right dysplastic kidney and 3 people with polycystic kidneys, already recognised). None of these abnormal findings led to a change in management.Conclusion: In view of the low yield of abnormal findings the use of routine ultrasounds for asymptomatic urinary abnormalities in such population might be re‐evaluated. Ultrasound might be reserved for people with special features, such as gross haematuria, rapid change in renal function, severe hypertension, elevated creatinine, clinical symptoms etc or in anticipation of a renal biopsy.