Haematuria associated with incident CKD in new AJKD study

Patients with haematuria may be at increased risk of chronic kidney disease (CKD)—that is the conclusion of a new study in the American Journal of Kidney Diseases (AJKD). Led my Yoo Jin Um (Seoul National University Hospital, Seoul, South Korea), the study authors performed a retrospective cohort analysis to investigate the risk of developing CKD associated with microscopic blood in a patient’s urine.

THE RETROSPECTIVE COHORT STUDY EXAMINED THE DATA OF 232,220 patients from the Kankbuk Samsung Health Study. The patients received “comprehensive health examinations” at least twice between 2011 and 2018, with a follow-up before the end of 2020. This examination included blood pressure, estimated glomerular filtration rate (eGFR), serum creatinine and other measurements. Urinalysis of protein and blood cells was performed of “fresh and midstream spot urine samples” of all patients, and haematuria changes were determined at baseline and follow-up. The primary endpoint of the study was incident CKD, while secondary endpoints included decreased eGFR and proteinuria.

The results showed a statistically significant association. Male patients who experienced persistent haematuria had an 8.3-fold increased risk of developing CKD, while those who developed it had a 4.4-fold increased risk and those whose haematuria regressed had a 2.2-fold increased risk. Women with persistent haematuria had a 4.4-fold increased risk and those who developed it had a 2.5-fold increased risk. Both were statistically significant, and the authors said it reflected that microscopic haematuria was “significantly associated with subsequent CKD incidence[…] in both sexes,” despite a stronger association for men.

One point the team noted is those microscopic haematuria in premenopausal women was “commonly considered a benign finding,” something brought into question by the results of their study. They call the reason for the sex-based differences “unclear,” requiring exploration in further studies. Finally, they note limitations, including the lack of renal biopsies among the patient cohort, which limited their data, as well as the overall low number of incident CKD in their study, something which they suggested should prompt further study. Nevertheless, they say such further study could build on the strengths of their own to determine “whether appropriate management of haematuria can help decrease subsequent CKD risk and progression to renal failure”.

Miniaturised Holly implantable dialysis device offers patients greater freedom

Dirk M Hentschel (Harvard Medical School, Cambridge, USA), president of the Vascular Access Society of the Americas (VASA), has presented on the new Holly portable device (Nephrodite) for haemodialysis. Designed as an “implantable continuous dialysis haemofiltration device blending haemodialysis and peritoneal dialysis in one device,” it purports to offer patients more freedom than both in-centre and home dialysis treatments.

THE PRESENTATION AT VEITHSYMPOSIUM (15–19 November, New York City, USA) began with a question—“why bother?” What makes an implantable device worth the investment for clinicians and their patients? The answer was multipronged, with Hentschel acclaiming the mobility gained and time saved by utilising products like Holly. The core of Holly’s utility is the freedom it gives to patients, he said. The ambition behind the device is to provide something “approaching continuous dialysis,” he continued, and that patients using the device “should reach stage 4 CKD kidney function (eGFR > 15ml/min)”. He outlined the core concepts behind the device, including miniaturisation of dialysis technology to allow it to be portable as well as the reuse of dialysate.

Hentschel was not afraid to outline the many challenges in designing a successful implantable dialysis device. Building a body-device connection was among them, as were the multiple risks associated with use of the device, which included both thrombosis and infection. There were also questions, Hentschel said, about how best to control the parameters of dialysis on the device after implantation.

He had answers to these questions, however. For controlling dialysis, he mooted the twin possibilities of an external device for controlling dialytic parameters as well as an internal one requiring a “biological kidney equivalent.” Holly itself, he said, operates on a hybrid system blending both of these approaches. Using a catheter coming out of the skin, it will connect to a wearable bag of dialysate fluid which patients can change themselves every four to six hours. This will give patients a new level of freedom even compared to existing home dialysis systems, Hentschel suggested.

Holly’s system brings its own challenges, however. Hentschel sketched a few of them, including those brought by the external reservoir connected to the system. The membrane of the device is subject to ageing and may mean it needs to be replaced, he said, while control of the micropump at the centre of Holly’s design also demands a solution and the dialysate needs to be monitored.

Disclosures: Dirk M Hentschel is a member of Nephrodite’s advisory board and has held equity in the company, as well as in BluegrassVascular.