Retrospective study on the epidemiology of antineutrophil cytoplasmic autoantibodies-associated vasculitis in two Australian health districts.

BACKGROUND: Antineutrophil cytoplasmic autoantibodies (ANCA)-associated vasculitis (AAV) is more prevalent in rural Australia compared with metropolitan areas, suggesting a role of environment in disease pathogenesis. However, the prevalence of environmental risk factors in Australian AAV patients has not been described. AIMS: To compare the incidence of AAV between two health districts (Illawarra Shoalhaven Local Health District (ISLHD), a mixed rural/metropolitan region, and South Eastern Sydney Local Health District (SESLHD), a metropolitan region) in Australia and its relationship to environmental exposures. METHODS: Cases of AAV from 2002 to 2017 were retrospectively identified from ISLHD and SESLHD using electronic medical records. Eligible participants were invited to complete a standardised questionnaire examining their exposure to silica, solvents, metal, dust, farming, gardening and sunlight. RESULTS: One hundred and fifty-six cases of AAV were identified from 2002 to 2017. A higher cumulative incidence of AAV was observed in the ISLHD (184.2 (95% confidence interval (CI) 143.6-232.7) per million) compared with SESLHD (102.6 (95% CI 82.1-126.8) per million). Over 50% of the cohort had high levels of silica and solvents exposure, based on self-reported questionnaires. There was no significant relationship between region and exposure to silica (P = 0.96), solvents (P = 0.44), metal (P = 0.33), dust (P = 0.25), farming (P = 0.90), gardening (P = 0.93) or sunlight (P = 0.55). CONCLUSIONS: We found a higher incidence of AAV in ISLHD compared with SESLHD with high levels of exposure to silica and solvents in both regions based on self-reported questionnaires. Prospective systematic collection of data, such as a registry of AAV, is warranted to further explore the relationship between environmental exposures and AAV.

Polyunsaturated fatty acid food frequency questionnaire validation in people with end stage renal disease on dialysis.

AIM: To validate the polyunsaturated food frequency questionnaire (PUFA FFQ) and test for reproducibility in people with end stage renal disease on dialysis treatment. METHODS: Participants (n = 32) completed the PUFA FFQ and three 24-hour recalls. Erythrocyte samples (n = 29) were used for erythrocyte fatty acid analysis. The triangular relationship between the PUFA FFQ, 24-hour recalls and the biomarker was assessed using the method of triads. Agreement between the two dietary methods was also assessed using Bland-Altman plots and classification by quintiles. Reproducibility was tested on a subset of the group (n = 8). RESULTS: The PUFA FFQ was a valid measure of all PUFA except for docosapentaenoic acid (DPA) and arachidonic acid (AA). Strong validity coefficients were found for n-3 long-chain PUFA (LCPUFA), eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA) of 0.914 (95% CI: 0.665, 0.997) and 0.889 (95% CI: 0.706, 0.994), respectively. In the Bland-Altman plots 91-100% of observations fell between the limits of agreement for all PUFA. There were significant correlations between the initial FFQ and the repeat FFQ for all PUFA except DPA and AA. CONCLUSIONS: The PUFA FFQ is a valid tool for assessing PUFA intake in people with end stage renal disease.

Diet quality in patients with end-stage kidney disease undergoing dialysis.

BACKGROUND: People on haemodialysis (HD) are at risk of consuming a poor quality diet. This includes inadequate intake of omega-3 long chain polyunsaturated fatty acids (n-3 LCPUFA). OBJECTIVE: This study aims to investigate diet quality, with a particular focus on n-3 LCPUFA intake, in a population of incentre HD patients. DESIGN: Dietary intake was measured using three 24 hour recalls; the Polyunsaturated food frequency questionnaire (PUFA FFQ) and the Total Diet Score (TDS). Dietary intake was also compared to evidence based practice guidelines (EBPG). Nutritional status was assessed using the Patient Generated Subjective Global Assessment (PG SGA). SUBJECTS: A total of 32 dialysis patients were recruited, from two regional HD centres in New South Wales, Australia. MAIN OUTCOME MEASURE: Diet quality was the main outcome measure. RESULTS: Diet quality of study participants was poor, with the majority not meeting the EBPG for energy, protein and potassium. All participants exceeded the recommended amount of saturated fat. The mean TDS of the dialysis cohort was 10.2, which was significantly higher than the TDS of 9.3 of a healthy disease free cohort (p < 0.05). Positive correlations were found between TDS and LC omega-3 intake (r = 0.392) and TDS and total omega-6 intake (r = 0.363). Only 22% of participants met the suggested dietary target for n-3 LCPUFA intake. CONCLUSION: Dialysis patients in this study had suboptimal diet quality. Improvements are required for better adherence to the EBPG. Increased consumption of n-3 LCPUFA fatty acids may also be of benefit.

Measuring protein excretion in pregnancy.

The recognition and detection of proteinuria has been acknowledged as an important clinical marker of renal disease since 1827 when Richard Bright published his landmark medical case reports. In more recent times, the broader community of clinicians has come to share the enthusiasm of nephrologists in recognizing the importance of protein excretion, not only as a marker of current renal disease but also as a predictor of long-term renal and cardiovascular morbidity and mortality. It is important that methods for detecting and measuring proteinuria are accurate, and this is particularly relevant to diseases that are defined by the detection of proteinuria, such as pre-eclampsia. This review will first discuss current knowledge of protein handling by the normal kidney, then the changes in normal and hypertensive pregnancy, and finally, how recent advances in our understanding of proteinuria may affect our future management of hypertensive pregnancies.

Microscopic hematuria in pregnancy: relevance to pregnancy outcome.

BACKGROUND: The significance of dipstick or microscopic hematuria in pregnancy is uncertain, with some studies suggesting this is associated with a greater risk for preeclampsia. We sought to determine the prevalence and clinical significance of microscopic hematuria during pregnancy. METHODS: This was a prospective case-control study in the antenatal Clinic of St George Hospital, Kogarah, Australia, a teaching hospital without tertiary referral antenatal care, with approximately 2,600 deliveries per year. One thousand pregnant women attending for routine antenatal care were invited to have a routine urinalysis performed and be referred to a nephrology clinic for further investigation if dipstick microscopic hematuria was detected on more than 1 occasion before 32 weeks' gestation. Main outcome measures were the prevalence of dipstick hematuria, prevalence of hematuria confirmed by urine microscopy, and the development of preeclampsia or gestational hypertension or delivery of a small-for-gestational-age baby. RESULTS: One hundred seventy-eight of 902 women (20%) who entered the study had dipstick hematuria on at least 2 occasions in pregnancy; 66 of 126 women (53%) who had hematuria before 32 weeks attended the nephrology clinic, where microscopic hematuria was confirmed in 40 women (61%). Renal imaging results were normal in all except 1 woman, and all women had a serum creatinine level of 0.90 mg/dL or less (< or =80 micromol/L). The development of preeclampsia or gestational hypertension or delivery of a small-for-gestational-age baby were similar in women with and without dipstick hematuria. Microscopic hematuria persisted in half (15 women) of those who attended for follow-up after 3 months postpartum. CONCLUSION: Dipstick hematuria is very common during pregnancy, but rarely signifies a disorder likely to impact on the pregnancy outcome. Postpartum follow-up is recommended to detect women who have persistent hematuria and presumed underlying mild glomerulonephritis.