Prevalence of kidney damage in Australian adults - the AusDiab Kidney Study

The incidence of ESRD is increasing dramatically. Progression to end-stage may be halted or slowed when kidney damage is detected at an early stage. Kidney damage is frequently asymptomatic but is indicated by the presence of proteinuria, hematuria, or reduced GFR. Population-based studies relating to the prevalence of kidney damage in the community are limited, particularly outside of the United States. Therefore, the prevalence of proteinuria, hematuria, and reduced GFR in the Australian adult population was determined using a cross-sectional study of 11,247 noninstitutionalized Australians aged 25 yr or over, randomly selected using a stratified, cluster method. Subjects were interviewed and tested for proteinuria—spot urine protein to creatinine ratio (abnormal: >=0.20 mg/mg); hematuria—spot urine dipstick (abnormal: 1+ or greater) confirmed by urine microscopy (abnormal: >10,000 red blood cells per milliliter) or dipstick (abnormal: 1+ or greater) on midstream urine sample; and reduced GFR—Cockcroft-Gault estimated GFR (abnormal: <60 ml/min per 1.73 m2). The associations between age, gender, diabetes mellitus, and hypertension, and indicators of kidney damage were examined. Proteinuria was detected in 2.4% of cases (95% CI: 1.6%, 3.1%), hematuria in 4.6% (95% CI: 3.8%, 5.4%), and reduced GFR in 11.2% (95% CI: 8.6%, 13.8%). Approximately 16% had at least one indicator of kidney damage. Age, diabetes mellitus, and hypertension were independently associated with proteinuria; age, gender, and hypertension with hematuria; and age, gender, and hypertension with reduced GFR. Approximately 16% of the Australian adult population has either proteinuria, hematuria, and/or reduced GFR, indicating the presence of kidney damage. Identifying and targeting this section of the population may provide a means to reduce the burden of ESRD.

Renal and gastrointestinal amyloidosis in an HIV-infected injection drug user

A 30-year-old HIV-infected intravenous drug user presented with sepsis, acute renal failure, oedema, proteinuria and iron deficiency anaemia. After extensive investigation, a diagnosis of reactive systemic AA (amyloid, serum amyloid A protein) amyloidosis was made on the basis of renal, gastric and duodenal biopsies.

Effects of exercise on the isoelectric patterns of erythropoietin

Objectives: Recombinant erythropoietin has a strong impact on aerobic power and is therefore one of the most potent doping agents in endurance sports. The anti-doping control of this synthetic hormone relies on the detection, in the urine, of its isoelectric pattern, which differs from that of the corresponding natural hormone, the latter being typically more acidic than the former. However, a small number of natural urinary patterns, referred to as atypical patterns, are less acidic than the dominant form. Based on anecdotal evidence, the occurrence of such patterns seems to be related to particular strenuous exercises. This study aimed to demonstrate this relation using a strenuous exercise protocol.

Design: Seven athletes took part in a training protocol including a series of supramaximal short-duration exercises. Urine and blood samples were collected throughout the protocols.

Settings: World Cycling Center, Aigle, Switzerland, and research laboratories.

Participants: Seven top-level athletes (cyclists) were involved in this study.

Main Outcome Measures: Erythropoietin (EPO) isoelectric patterns were obtained by submitting blood and urine samples to isoelectric focusing. Additional protein dosages were performed.

Results: Supramaximal short-duration exercises induced the transformation of typical urinary natural EPO patterns into atypical ones. None of the obtained atypical patterns fulfilled the 3 criteria mandatory for reporting an adverse analytical finding. Serum EPO patterns were not affected by the exercises that caused the transformation of urinary patterns.

Conclusion: An exercise-induced transient renal dysfunction is proposed as a hypothetic explanation for these observations that rely on parallel investigations of proteinuria in the same samples.