#06 Newsletter December 18, 2021

Hello and welcome to the stone newsletter, where we discuss every 2 months the most recent and relevant studies in stone disease.

Suscribe now

Themes introduction

Welcome to this last edition of the 2021 Stone News cycle. In this issue we will be focusing on contributing factors for stone formation (especially uric acid stones) and most important recurrence prevention with the use of new technologies. Also, as stone disease if often related to reduced renal function, we will see how PCNL and SWL can affect those patients with renal insufficiency which is a common question among urologists.
I hope that this edition of Stone News will provide you with more tools to help patients with stone recurrence and choosing the proper treatment approaches in patients with urolithiasis.

img The impact of metabolic syndrome components on urinary parameters and risk of stone formation. img 3'
https://pubmed.ncbi.nlm.nih.gov/34264364/ img

Metabolic syndrome (MS) is highly prevalent, reaching up to one quarter of the world's population. MS is defined as the presence of three or more of the five following coexisting conditions: obesity, hyperlipidemia (HLD), hypertriglyceridemia (HTG), diabetes mellitus (DM), hypertension of which insulin resistance (and DM) has been related to decreased urinary pH thus stone formation. In such patients a 24h urine study must be performed in order to evaluate further metabolic alterations that are related to stones recurrence.

In this study the authors compared the association of MS coexisting conditions with the 24h urine sample. In the study 495 patients were included and evaluated regarding their MS severity scores (ranging from 0: less severe, to 5: most severe). The interesting findings of this study reflects that not only DM and insulin resistance but also HTG, hypertension and obesity were independently associated with changes in urinary parameters, especially low urinary pH. Usually in this patients, a mixed Calcium Oxalate Monohydrated stone and a uric acid stone is seen, this was reflected in the study showing how Calcium Oxalate Monohydrated stones were present in 79% in patients with low grade MS while increasing MS severity increased uric acid stones due to decreased urinary pH and an upward trend of urinary uric acid supersaturation.

Finally, we need to be aware that urinary stones are another symptom of a large problem. We need to be aware of the MS patient’s pH changes and evaluate them with 24h urine samples and stone analysis to provide them the best of cares. Also to encourage the patient to be treated of each one of the MS components to decrease stone formation.

img Pilot study of the usability and functionality of a smart pH meter and a mobile medical application for urine ph monitoring. img 3'
https://pubmed.ncbi.nlm.nih.gov/34472438/ img

As we saw previously, pH monitoring is crucial in some stone formers, specially, uric acid stones, cystine stones and struvite stones were urinary pHs have been shown to decrease crystal formation and even stone dissolution.

Nowadays new technologies are emerging to allow patients better control of their disease with more reliable monitoring methods specially for pH measurements were the accuracy is crucial to ensure a proper treatment response.

For these healthy volunteers portable pH-meters have been found to be reliable. In this study the Lit-Control® pH Meter was tested in 21 patients between (26 and 61 years of age) for 14 days. The pH meter included a mobile app to download and control the monitoring by Bluetooth. Subjects had to monitor their urine pH three times a day that resulted on a yielded average values of 5.72. Only 72% of all recordings were done being performed mostly in the mornings, shows us how real life measurements will are. This information is highly valuable as this give us perspective on how to counsel patients in order to have the best adherence to the treatment/monitoring (Better to tell them to measure the pH in the morning or at night rather than at midday).

Also 73% of the subjects were able to download and use correctly the app. We must trust that our patients nowadays (and in the near future) finds easy the use of new technologies; Also as seen in the study this app allows the patients to include remainders, passwords to protect for personal data and easy uploading of data witch were seen of great value.

Is good to mention that we are seeing more and more tools that allows our patients to ensure better and easier monitoring (control of their own disease) with the possible benefit of increasing treatment adherence thus lowering stone recurrence.

img Percutaneous nephrolithotomy versus extracorporeal shock wave lithotripsy for renal insufficiency. img 3'
https://pubmed.ncbi.nlm.nih.gov/34076752/ img

Urolithiasis is a disease linked to renal insufficiency which may appear because of a lack of proper follow up or chronic or silent urinary obstruction and infection. As treatments have been developed urologists have always tried to avoid treatment related renal injuries and renal insufficiency. The objective of his randomized controlled trial was to compare patients with renal insufficiency (eGFR < 60 ml/min/1.73 m2) undergoing PCNL or SWL to evaluate treatment effects and outcomes.

With similar demographics among groups the stone size was 23 mm for the PCNL group and 22 mm for the SWL group (which is recommended as second line of treatment according to the EAU guidelines). This is probably why the stone free rate was 92% for the PCNL group and 26.6% for the SWL group (even considering stone free patients with 3 mm fragments) after a single SWL session.

After 3 months of PCNL and SWL a 9.1% and 8.7% of serum creatinine improvement was seen respectively. This finding are in accordance with clinical recommendations. Even if you may access the kidney or give them shock waves the improvement of renal function by treating a stone is greater than the possible harm.

Also, it was interesting to see that PCNL (the most invasive treatment) had a better renal function improvement (creatinine clearance) than the least invasive technique; Although GFR was higher for the PCNL group (5.6 vs 2.6) it was not statistically significant. We need to remember that not also stone free rates but also the preservation of kidney function is one of the main objectives of our treatments.

This study is another example of how PCNL and SWL can be safely used in patients with renal insufficiency, and even more, improve patients renal function.

facebook twiter youtube instagram
Aviso Legal | Política de privacidada
Este mail ha sido enviado a {{ contact.email }} por Devicare Lit Control.
Si quiere darse de baja de las comunicaciones de la Stone News puede enviarnos un correo electrónico a
dop@devicare.com o pinchar aquí.
Av. Can Domènech s/n | Eureka Building UAB Research Park | 08193 Cerdanyola del Vallès,
Barcelona | España
Copyright (c) 2021 Devicare Lit-Control.