Medical Therapy of Urolithiasis

Herbal remedies for urinary stones used in India and China: A review

ETHANOPHARMACOLOGICAL RELEVANCE

The process of formation or appearance of a urinary stone anywhere in the renal tract is known as urolithiasis. It is a longstanding health problem, known to exist since early age of civilization. Records about symptoms, signs and treatment strategies of urinary stones diseases are found in the several ancient texts of traditional medicines such as Ayurveda, Traditional Chinese Medicine (TCM), Siddha and Unani. In Ayurveda, urolithiasis has been considered as one of the eight most troublesome diseases. Ayurvedic management and cure of urinary stone involves herbal formulas, alkaline liquids and surgical procedures. Whereas, TCM recommends polyherbal drugs, acupuncture and mexibustion for treatment of the urinary stones. Among these therapies, herbal remedies are in practice till today for the treatment and cure urinary stone diseases.

MATERIALS AND METHODS

A comprehensive review of the scientific literature about pathophysiology of urinary stones and antiurolithiatic plants was undertaken using the following bibliographic databases: MEDLINE/PubMed, Scopus, Web of Knowledge and Google Scholar. The search was conducted from publications from all years until Dec., 2015 by combination of the search terms and Boolean operators; 'urinary stone' OR 'kidney stone' AND 'plant' OR 'medicine' OR 'antiurolithiatic plants'. Outputs were restricted to those completed studies only published in English. In this review, literatures about plants which are used as diuretic and/or in treatment urinary tract infections have not also been considered. The Plant List and Royal Botanical Garden, Kew databases were used to authenticate botanical names of plants. Books and monographs published in English were used to collect information about historical records of antiurolithiatic plants.

RESULTS

Recent pharmacological interventions accredited ancient antiurolithiatic claims to several plants and their formulations. The majority of antiurolithiatic plants were found to either dissolve the stones or inhibit the process of urinary stone formation. Plants such as Phyllanthus niruri L. and Elymus repens (L.) Gould, as well as herbal products including 'Wu-Ling-San' formula, 'Cystone' and 'Herbmed' have been proved their utility as promising antiurolithiatic medicines in the different phases of clinical trials. In addition, some of the isolated phytochemicals such as berberine, lupeol, khelin, visnagin, 7-hydroxy-2',4',5'-trimethoxyisoflavone and 7-hydroxy-4'-methoxyisoflavone were reported to have potent antiurolithiatic activity.

CONCLUSION

In ancient medicinal texts, antiurolithiatic potential has been ascribed to several plants and their formulations. Present scientific studies provide scientific evidences for few of these claims however, they are insufficient to establish many of these plants and herbal formulations as therapeutic remedies for the treatment and management of urinary stones. Conversely, findings of pre-clinical and clinical studies about some plants and herbal formulations are promising, which underlines the utility of herbal remedies as alternative medicines for the treatment and management of urinary stones in the future.

A retrospective analysis of nebulized versus intravenous fentanyl for renal colic

STUDY OBJECTIVE

To assess the effectiveness of nebulized fentanyl used for analgesia in renal colic.

MATERIALS/METHODS

This research was planned as a randomized, blinded study in which prospectively collected data were analyzed retrospectively to compare nebulized and intravenous (iv) fentanyl therapies. Patients with renal colic with 'moderate' or worse pain on a four-point verbal pain score (VPS) or with pain of 20mm or above on a 100-mm visual analogue score (VAS) at time of presentation were randomized into iv fentanyl (n=62) or nebulized fentanyl (n=53) study groups. Decreases in VAS and VPS scores at 15 and 30min compared to baseline, rescue analgesia requirements and side-effects between the groups were compared.

RESULTS

Both iv fentanyl and nebulized fentanyl provided effective analgesia in renal colic patients at the end of 30min. However, iv fentanyl provided more rapid and more effective analgesia than nebulized fentanyl. Patients receiving iv fentanyl had lower rescue analgesia requirements than those receiving nebulized fentanyl (37.1% vs 54.7%), although the difference was not statistically significant (p=0.058). In addition, side-effects were more common in the iv fentanyl group compared to the nebulized fentanyl group (22.1% vs 9.4%), although the difference was also not significant (p=0.058).

CONCLUSION

Nebulized fentanyl provides effective analgesia in patients with renal colic. However, iv fentanyl exhibits more rapid and more powerful analgesic effects than nebulized fentanyl. Nonetheless, due to its ease of use and few potential risks and side-effects the nebulized form can be used as an alternative in renal colic.

Urolithiasis--an interdisciplinary diagnostic, therapeutic and secondary preventive challenge

BACKGROUND

The prevalence of urolithiasis in Germany is 4.7%; its incidence has trebled in the last three decades. The risk of recurrence is 50-80%, depending on the type of stone, unless secondary prevention is instituted. Risk-adapted secondary prevention lowers this risk to 10-15%.

METHODS

This review is based on publications retrieved by a selective search in PubMed using the key words "urolithiasis," "urinary stones," "epidemiology," "lithogenesis," "biominerals," "risk factors," and "diagnosis, therapy, metaphylaxis." These publications were evaluated with the aid of the urolithiasis guideline of the European Association of Urology.

RESULTS

Acute renal colic can usually be diagnosed without sophisticated equipment. Stones can be dealt with by a variety of techniques depending on their size and location, including extracorporeal shock-wave lithotripsy, ureterorenoscopy, percutaneous nephrolitholapaxy, and open surgery. Most ureteric stones of diameter up to 5 mm pass spontaneously. 75% of patients have no complications. The basic evaluation needed for secondary prevention can be carried out by any physician on an ambulatory basis. In the 25% of patients who have complications, a more extensive interdisciplinary evaluation of metabolic parameters should be performed in a clinical center for urinary stones.

CONCLUSION

Urolithiasis has many causes and can be treated in many different ways. An extensive metabolic work-up is often necessary for secondary prevention. The various treatment options must be considered for their suitability in each individual patient. Robust data are now available on surgical and interventional methods, but there are as yet no high-quality trials of secondary prevention. Further research should concentrate on the etiology and pathogenesis of urolithiasis.

Recent finding and new technologies in nephrolitiasis: a review of the recent literature

This review summarizes recent literature on advances regarding renal and ureteral calculi, with particular focus in areas of recent advances in the overall field of urolithiasis. Clinical management in everyday practice requires a complete understanding of the issues regarding metabolic evaluation and subgrouping of stone-forming patients, diagnostic procedures, effective treatment regime in acute stone colic, medical expulsive therapy, and active stone removal. In this review we focus on new perspectives in managing nephrolitihiasis and discuss recentadvances, including medical expulsive therapy, new technologies, and refinements of classical therapy such as shock wave lithotripsy, give a fundamental modification of nephrolithiasis management. Overall, this field appears to be the most promising, capable of new developments in ureterorenoscopy and percutaneous approaches. Further improvements are expected from robotic-assisted procedures, such as flexible robotics in ureterorenoscopy.

Hyperoxaluria-induced tubular ischemia: the effects of verapamil and vitamin E on apoptotic changes with an emphasis on renal papilla in rat model

An experimental study in rats was performed to evaluate the presence and the degree of both tubular apoptotic changes and crystallization at cortical, medullar and papillary regions of the kidney during hyperoxaluric phase and assess the possible protective effects of vitamin E and verapamil on these pathologic changes (particularly in papillary part of the affected kidneys). A total of 32 rats have been included into the study program. Hyperoxaluria was induced by continuous administration of ethylene glycol (0.75%). In addition to hyperoxaluria induction, animals in Groups 2 and 3 did receive a calcium channel-blocking agent (verapamil) and vitamin E, respectively. Histologic alterations of the kidneys including crystal formation together with apoptotic changes were evaluated on days 1, 14 and 28, respectively. Both apoptotic changes and the presence and degree of crystallization were assessed separately in renal cortical region, medulla and particularly papillary parts of the removed kidneys. Although verapamil did well limit the degree of crystal formation and apoptosis and brought it to the same levels observed in control group animals in all parts of the kidneys during intermediate phase, addition of vitamin E was failed to show the same protective effect during both intermediate and late phase evaluations. As demonstrated in our study, the limitation of both crystal deposition and apoptotic changes might be instituted by calcium channel-blocking agents. Clinical application of such agents in the prophylaxis of stone disease might limit the formation of urinary calculi, especially in recurrent stone formers.

1,2,3,4,6-penta-O-galloyl-beta-D-glucose attenuates renal cell migration, hyaluronan expression, and crystal adhesion

Calcium oxalate monohydrate (COM) crystals bind avidly to the surface of proliferating and migrating renal endothelial cells, and oxalate-induced peroxidative injury can promote crystal attachment to renal epithelial cells. 1,2,3,4,6-penta-O-galloyl-beta-D-glucose (PGG), isolated from a traditional herbal remedy, inhibits vascular endothelial growth factor (VEGF) stimulated proliferation and migration of human umbilical vein endothelial cells (HUVECs) and has antioxidant activity. This study was performed to determine if PGG altered calcium oxalate monohydrate (COM) crystal adhesion to cells, perhaps via a change in cell surface properties. PGG significantly decreased COM crystal adhesion to cultured MDCK I cells at a low concentration (<10 microM) which was not cytotoxic. PGG exerted anti-adhesion effects whether cells or crystals were pre-coated. PGG also inhibited cell migration after scrape-wounding, decreased subsequent adhesion of crystals to proliferating and migrating cells, and decreased expression of the crystal binding molecule hyaluronan. These findings suggest that PGG represents a potential urolithiasis prevention compound. Anti-crystal adhesion effects appear multifaceted involving crystal coating by PGG, as well as decreased cell migration and the associated surface expression of hyaluronan. The latter represents a novel mechanism of nephrolithiasis prevention.

Oxalate in renal stone disease: the terminal metabolite that just won't go away

The incidence of calcium oxalate nephrolithiasis in the US has been increasing throughout the past three decades. Biopsy studies show that both calcium oxalate nephrolithiasis and nephrocalcinosis probably occur by different mechanisms in different subsets of patients. Before more-effective medical therapies can be developed for these conditions, we must understand the mechanisms governing the transport and excretion of oxalate and the interactions of the ion in general and renal physiology. Blood oxalate derives from diet, degradation of ascorbate, and production by the liver and erythrocytes. In mammals, oxalate is a terminal metabolite that must be excreted or sequestered. The kidneys are the primary route of excretion and the site of oxalate's only known function. Oxalate stimulates the uptake of chloride, water, and sodium by the proximal tubule through the exchange of oxalate for sulfate or chloride via the solute carrier SLC26A6. Fecal excretion of oxalate is stimulated by hyperoxalemia in rodents, but no similar phenomenon has been observed in humans. Studies in which rats were treated with (14)C-oxalate have shown that less than 2% of a chronic oxalate load accumulates in the internal organs, plasma, and skeleton. These studies have also demonstrated that there is interindividual variability in the accumulation of oxalate, especially by the kidney. This Review summarizes the transport and function of oxalate in mammalian physiology and the ion's potential roles in nephrolithiasis and nephrocalcinosis.

A systematic review of medical therapy to facilitate passage of ureteral calculi

STUDY OBJECTIVE

Acute renal colic is a common presenting complaint to the emergency department. Recently, medical expulsive therapy using alpha-antagonists or calcium channel blockers has been shown to augment stone passage rates of moderately sized, distal, ureteral stones. Herein is a systematic evaluation of the use of medical expulsive therapy to facilitate ureteral stone expulsion.

METHODS

We searched the databases of MEDLINE, EMBASE, and the Cochrane Controlled Trials Register. Additional sources included key urologic journals and bibliographies of selected articles. We included studies that incorporated a randomized or controlled clinical trial design, patients older than 18 years, treatment in which an alpha-antagonist or calcium channel blocker was compared to a standard therapy group, and studies that reported stone expulsion rates. A random effects model was used to obtain summary risk ratios (RRs) and 95% confidence intervals (CIs) for stone expulsion rate.

RESULTS

A pooled analysis of 16 studies using an alpha-antagonist and 9 studies using a calcium channel blocker suggested that the addition of these agents compared to standard therapy significantly improved spontaneous stone expulsion (alpha-antagonist RR 1.59; 95% CI 1.44 to 1.75; number needed to treat 3.3 [95% CI 2.1 to 4.5]; calcium channel blocker RR 1.50; 95% CI 1.34 to 1.68; number needed to treat 3.9 [95% CI 3.2 to 4.6]) in patients with distal ureteral stones. Subgroup analysis of trials using concomitant medications (ie, low-dose steroids, antibiotics, and elimination of trials using an anticholinergic agent) yielded a similar improvement in stone expulsion rate. Adverse effects were noted in 4% of patients receiving alpha-antagonist and in 15.2% of patients receiving calcium channel blockers.

CONCLUSION

Our results suggest that "medical expulsive therapy," using either alpha-antagonists or calcium channel blockers, augments the stone expulsion rate compared to standard therapy for moderately sized distal ureteral stones.