Pathophysiology of Reno-Ureteral Colic

Clinical characteristics of surgically managed patients with asymptomatic renal stones: Comparison of patients with symptomatic renal stones

PURPOSE

This study aimed to compare the characteristics of asymptomatic and symptomatic nephrolithiasis in patients who underwent surgical treatment for kidney stones.

MATERIALS AND METHODS

Between 2015 and 2019, 245 patients who underwent percutaneous nephrolithotomy or retrograde intrarenal surgery for kidney stones were included. The patients were divided into asymptomatic (n=124) and symptomatic (n=121) groups. All patients underwent blood and urine tests, preoperative non-contrast computed tomography, and postoperative stone composition analysis. We retrospectively analyzed and compared the characteristics of the patients and stones, operation time, stone-free rate, and postoperative complications between the two groups.

RESULTS

In the asymptomatic group, mean body mass index (BMI) was significantly higher (25.7±3.8 kg/m² vs. 24.3±2.8 kg/m², p=0.002) and urine pH was significantly lower (5.6±0.9 vs. 5.9±0.9, p=0.013). The ratio of calcium oxalate dihydrate stones was significantly higher in the symptomatic group (5.3% vs. 15.5%, p=0.023). No significant differences were observed in stone characteristics, postoperative outcomes, or complications. In the multivariate logistic regression analysis for predicting variables for asymptomatic renal stones, BMI (odds ratio [OR], 1.144; 95% confidence interval [CI], 1.038-1.260; p=0.007), and urine pH (OR, 0.608; 95% CI, 0.407-0.910; p=0.016) were independent predictive variables for asymptomatic renal stones.

CONCLUSIONS

This study demonstrated that thorough medical check-ups are needed for the early detection of renal stones in individuals with a high BMI or low urine pH.

Effect of Adjunctive Acupuncture on Pain Relief Among Emergency Department Patients With Acute Renal Colic Due to Urolithiasis: A Randomized Clinical Trial

IMPORTANCE

Renal colic is described as one of the worst types of pain, and effective analgesia in the shortest possible time is of paramount importance.

OBJECTIVES

To examine whether acupuncture, as an adjunctive therapy to analgesics, could accelerate pain relief in patients with acute renal colic.

DESIGN, SETTING, AND PARTICIPANTS

This single-center, sham-controlled, randomized clinical trial was conducted in an emergency department in China between March 2020 and September 2020. Participants with acute renal colic (visual analog scale [VAS] score ≥4) due to urolithiasis were recruited. Data were analyzed from October 2020 to January 2022.

INTERVENTIONS

After diagnosis and randomization, all patients received 50 mg/2 mL of diclofenac sodium intramuscular injection immediately followed by 30-minute acupuncture or sham acupuncture.

MAIN OUTCOMES AND MEASURES

The primary outcome was the response rate at 10 minutes after needle manipulation, which was defined as the proportion of participants whose VAS score decreased by at least 50% from baseline. Secondary outcomes included response rates at 0, 5, 15, 20, 30, 45, and 60 minutes, rescue analgesia, and adverse events.

RESULTS

A total of 115 participants were screened and 80 participants (66 men [82.5%]; mean [SD] age, 45.8 [13.8] years) were enrolled, consisting of 40 per group. The response rates at 10 minutes were 77.5% (31 of 40) and 10.0% (4 of 40) in the acupuncture and sham acupuncture groups, respectively. The between-group differences were 67.5% (95% CI, 51.5% to 83.4%; P < .001). The response rates of acupuncture were also significantly higher than sham acupuncture at 0, 5, 15, 20 and 30 minutes, whereas no significant difference was detected at 45 and 60 minutes. However, there was no difference between the 2 groups in rescue analgesia rate (difference 2.5%; 95% CI -8.8% to 13.2%; P > .99). No adverse events occurred during the trial.

CONCLUSIONS AND RELEVANCE

These findings suggest that acupuncture plus intramuscular injection of diclofenac is safe and provides fast and substantial pain relief for patients with renal colic compared with sham acupuncture in the emergency setting. However, no difference in rescue analgesia was found, possibly because of the ceiling effect caused by subsequent but robust analgesia of diclofenac. Acupuncture can be considered an optional adjunctive therapy in relieving acute renal colic.

TRIAL REGISTRATION

Chinese Clinical Trial Registry: ChiCTR1900025202.

Sterile water injections for management of renal colic pain: a systematic review

BACKGROUND

Since the 1950s a small number of centres have used sterile water injections (SWI) to treat renal colic pain. We undertook this review to determine the efficacy of SWI to manage the pain of renal colic.

METHODS

We searched the electronic databases PubMed, Cochrane Central Register, CINAHL, and Scopus from database inception to 7 November 2021 for randomized controlled trials that met the inclusion criteria.

RESULTS

Six trials were included in the review (n = 894 patients). Two placebo controlled trials were included in the meta-analysis. Other trials compared SWI to Diclofenac, Morphine, or oral Paracetamol. The overall quality of the trial was low. Compared to a placebo SWI demonstrated a significant reduction in self-reported pain at 30 min (Mean difference [MD] = -4.68, 95% Confidence Interval [CI] = -5.21, -4.15. p < 0.001, I² = 0%) and at or beyond 60 min post-injection (MD = -5.34 95% CI = -5.85, -4.82, p ≤ 0.001, I² = 0%). Pain relief provided by SWI was significantly better than oral paracetamol and equivalent to Diclofenac and Morphine. No significant side-effects were attributed to SWI use in any trials.

DISCUSSION/CONCLUSION

SWI could be a suitable alternative for management of renal colic pain where alternatives such as non-steroidal anti-inflammatory and opioid drugs are either unavailable or contraindicated. However, further research is required to establish the role of SWI in renal colic pain management.

Erector spinae plane block vs non-steroidal anti-inflammatory drugs for severe renal colic pain: A pilot clinical feasibility study

AIM

Ultrasound-guided plane blocks are increasingly used in the multi-modal analgesic concept for reducing opioid consumption. The present study was conducted to compare the analgesic effect of intravenous non-steroidal anti-inflammatory drugs (NSAIDs) and erector spinae plane (ESP) block in renal colic patients.

METHODS

In this prospective randomised study, 40 patients with renal colic pain were randomly assigned into two groups: Group NSAID (n = 20) received an intravenous infusion of 50 mg of dexketoprofen trometamol and Group ESP (n = 20) received ultrasound-guided ESP block with 30 ml 0.25% bupivacaine at the T8 level. The pain severity of patients was assessed using the visual analogue scale (VAS) at baseline, 5, 15, 30, 45 and 60 minutes after intervention. Opioid consumption, patient satisfaction and side effects were recorded.

RESULTS

In the ESP group, the VAS scores were significantly lower than the NSAID group at 5, 15, 30, 45 and 60 minutes after the procedure (P < .001). Opioid consumption was significantly higher in the NSAID group compared with the ESP group (10/20 vs 0/20, respectively; P < .001). Patient satisfaction was significantly higher in the ESP group (P < .001).

CONCLUSIONS

ESP block can be an alternative, efficient and safe method for the relief of acute renal colic pain.

“Mirror” ureteric colic caused by proximal ureteric calculus in massively hydronephrotic kidney

Patients with ureteric calculi usually present with ipsilateral “loin to groin” pain. Rarely ureteric colic may present with contralateral pain, which is referred to as “mirror pain”. We report the case notes of a rare presentation of contralateral ureteric colic or “mirror pain” secondary to a ureteric calculus. A comprehensive literature review was also conducted.

“Mirror pain” or contralateral ureteric colic is rare. Urologists should be aware of this unusual clinical presentation and appreciate that upper urinary tract calculi can cause pain on the contralateral side.

Comparative efficacy and safety of analgesics for acute renal colic: A network meta-analysis protocol

INTRODUCTION

Acute renal colic is one of the most common urological emergencies. While previous randomized controlled trials (RCTs) and pairwise meta-analyses only looked at the efficacy of 1 or 2 analgesics. It is not fully understood that the comprehensive ranking of the effectiveness and safeness of analgesics from these published articles. Therefore, this network meta-analysis (NMA) aims to compare and rank the different analgesics for treatment of acute renal colic.

METHODS AND ANALYSIS

We will perform a systematic literature search in PubMed, EMBASE, CINAHL, Web of Science, and Cochrane Library to identify RCTs of different analgesics for acute renal colic. RCTs assessing active analgesics intervention against active comparator or placebo controls for acute renal colic will be included. We will also screen the reference lists of included studies, previous reviews and meta-analyses to identify other relevant trials. The primary outcomes will be pain variance at 30 minutes, need rescue medicine, complete pain relief or at least 50% pain relief at 30 minutes, and pain relapse within 24 hours. We will also assess secondary outcomes for safeness (side effects: dizziness, vomit, allergic, hypotension, cardiac toxicity, and drug dependence). The risk of bias of included RCTs will be assessed by using the Cochrane Collaboration's tool, and the quality of evidence will be assessed by using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) instrument. We will perform pairwise meta-analysis and Bayesian NMA to compare the effectiveness and safeness of different analgesic interventions.

RESULTS

This NMA will compare and rank the different analgesics for treatment of acute renal colic.

CONCLUSION

This is the first systematic review to use the NMA to comprehensively compare and rank analgesics for relieving pain of acute renal colic in adults based on most important factors deciding the choice of initial analgesia, and the results can provide implications for clinical practice and further research.

Pacemaker Mechanisms Driving Pyeloureteric Peristalsis: Modulatory Role of Interstitial Cells

The peristaltic pressure waves in the renal pelvis that propel urine expressed by the kidney into the ureter towards the bladder have long been considered to be 'myogenic', being little affected by blockers of nerve conduction or autonomic neurotransmission, but sustained by the intrinsic release of prostaglandins and sensory neurotransmitters. In uni-papilla mammals, the funnel-shaped renal pelvis consists of a lumen-forming urothelium and a stromal layer enveloped by a plexus of 'typical' smooth muscle cells (TSMCs), in multi-papillae kidneys a number of minor and major calyces fuse into a large renal pelvis. Electron microscopic, electrophysiological and Ca²⁺ imaging studies have established that the pacemaker cells driving pyeloureteric peristalsis are likely to be morphologically distinct 'atypical' smooth muscle cells (ASMCs) that fire Ca²⁺ transients and spontaneous transient depolarizations (STDs) which trigger propagating nifedipine-sensitive action potentials and Ca²⁺ waves in the TSMC layer. In uni-calyceal kidneys, ASMCs predominately locate on the serosal surface of the proximal renal pelvis while in multi-papillae kidneys they locate within the sub-urothelial space. 'Fibroblast-like' interstitial cells (ICs) located in the sub-urothelial space or adventitia are a mixed population of cells, having regional and species-dependent expression of various Cl^-, K⁺, Ca²⁺ and cationic channels. ICs display asynchronous Ca²⁺ transients that periodically synchronize into bursts that accelerate ASMC Ca²⁺ transient firing. This review presents current knowledge of the architecture of the proximal renal pelvis, the role Ca²⁺ plays in renal pelvis peristalsis and the mechanisms by which ICs may sustain/accelerate ASMC pacemaking.

Comparison the analgesic effect of magnesium sulphate and Ketorolac in the treatment of renal colic patients: Double-blind clinical trial study

BACKGROUND

Ureter muscles contraction movements caused pain in renal colic. Magnesium sulphate could influence the pain by reducing acetylcholine in the nerve terminals. We have aimed to evaluate the analgesic effects of magnesium sulphate on acute renal colic pain.

METHOD

In this double-blind clinical trial study, the patients with renal colic pain were randomly divided into 2 groups; Group I received an intravenous infusion of 30 mg of Ketorolac and normal saline as placebo, Group II 50 mg/kg magnesium sulphate 50%/100 ml normal plus 30 mg of Ketorolac. The pain severity of patients was assessed using the visual analog scale (VAS) at baseline, and 15 and 30 min after intervention.

RESULTS

Baseline pain score and demographic characteristics did not significantly different between the groups. After 30 min the pain score significantly reduced in both groups. While, at 15 and 30 min, mean pain score did not show statistically significant differences.

CONCLUSION

Our findings indicated that Magnesium sulphate did not influence renal colic pain relief.

Elevated Renal Pelvic Pressures during Percutaneous Nephrolithotomy Risk Higher Postoperative Pain and Longer Hospital Stay

PURPOSE

Renal pelvic pressure may vary during percutaneous nephrolithotomy. We sought to determine the relationship of postoperative pain to endoscope caliber, renal pelvic pressure and hospital stay.

MATERIALS AND METHODS

We reviewed the records of 20 percutaneous nephrolithotomies done under ureteroscopic guidance with renal pelvic pressure monitoring. The ureteroscope working channel was connected to a pressure transducer and used to determine renal pelvic pressure at baseline, when irrigating with a 26Fr rigid nephroscope and a 16Fr flexible nephroscope, and during suction. Patient demographics, operative characteristics, Likert pain scores and length of hospital stay were compared as stratified by average renal pelvic pressure. The Mann-Whitney U and Fisher exact tests were used with p <0.05 considered significant.

RESULTS

A total of 220 measurements were recorded in 20 patients undergoing single access percutaneous nephrolithotomy. Mean patient age was 55.2 years (range 20 to 77) and mean body mass index was 32.4 kg/m² (range 18 to 53.3). Rigid nephroscopy resulted in significantly higher average renal pelvic pressure than flexible nephroscopy (30.3 vs 12.9 mm Hg, p = 0.007). Average renal pelvic pressure was 30 mm Hg or greater in 7 patients (35%) undergoing rigid nephroscopy and in none (0%) undergoing flexible nephroscopy (p <0.01). Patients exposed to an average renal pelvic pressure of 30 mm Hg or greater during rigid nephroscopy had significantly higher average pain scores (p = 0.004) and longer hospital stays (p = 0.04) than patients with renal pelvic pressure less than 30 mm Hg. Average renal pelvic pressure 30 mm Hg or greater during rigid nephroscopy was also associated with a longer skin to calyx distance (105.5 vs 79.7 mm, p = 0.03).

CONCLUSIONS

Knowledge of the factors that influence renal pelvic pressure and methods to control pressure extremes may improve patient outcomes during percutaneous nephrolithotomy.

Predicting procedural pain after ureteroscopy: does hydrodistention play a role?

Purpose:

To identify perioperative predictors of immediate pain after ureteroscopy, specifically evaluating the impact of hydrodistention from irrigation on pain.

Materials and Methods:

We retrospectively identified patients who underwent ureteroscopy for the treatment of calculi. Data recorded for these patients included their maximum pain score in the post-anesthesia care unit (PACU), average flow rate of irrigant used during the procedure, patient and stone characteristics, operative procedure, and details of patients' immediate, post-operative course. Spearman's rho was used to determine the relationship between non-parametric, continuous variables. Then, a linear regression was performed to assess which variables could predict the peak pain score.

Results:

A total of 131 patients were included in the study. A non-parametric correlation analysis revealed that maximum pain score was negatively correlated with being male (r = −0.18, p=0.04), age (r = −0.34, p<0.001), and post-op foley placement (r = −0.20, p=0.02) but positively correlated with the preoperative pain score (r = 0.41, p<0.001), time in the PACU (r = 0.19, p = 0.03), and the morphine equivalent dose (MED) of narcotics administered in the PACU (r = 0.67, p<0.001). On linear regression, the significant variables were age, preoperative pain score, and stent placement. For every ten-year increase in age post-operative pain score decreased by 4/10 of a point (p = 0.03). For every 1 point increase in preoperative pain score there was a 3/10 of a point increase in the maximum pain score (p = 0.01), and leaving a stent in place post-operatively was associated with a 1.6 point increase in the maximum pain score.

Conclusions:

Hydrodistention does not play a role in post-ureteroscopy pain. Patients who are younger, have higher preoperative pain scores, or who are stented will experience more post-operative pain after ureteroscopy.

Urolithiasis in the emergency department

Urolithiasis commonly presents to the emergency department with acute, severe, unilateral flank pain. Patients with a suspected first-time stone or atypical presentation should be evaluated with a noncontrast computed tomography scan to confirm the diagnosis and rule out alternative diagnoses. Narcotics remain the mainstay of pain management but in select patients, nonsteroidal anti-inflammatories alone or in combination with narcotics provide safe and effective analgesia in the emergency department. Whereas most kidney stones can be managed with pain control and expectant management, obstructing kidney stones with a suspected proximal urinary tract infection are urological emergencies requiring emergent decompression, antibiotics, and resuscitation.

Contractile effects of endothelins on isolated human ureter

The aim of our study was to investigate mechanism of action of endothelins 1, 2 and 3 on spontaneous activity, tone and intraluminal pressure of human ureter. Both longitudinal tension and intraluminal pressure were recorded from the isolated segments of proximal human ureter. Endothelins 1, 2 and 3 (5.35x10(-11) M - 5.05x10(-8) M) produced concentration-dependent tonic contraction and sustained increase in intraluminal pressure of isolated preparations of human ureter. Endothelins 1 and 3 produced also concentration-dependent inhibition of spontaneous, phasic contractions of the isolated preparations. Selective antagonist of ET(A) receptors BQ123 and selective antagonist of ET(B) receptors BQ788 produced significant inhibition of endothelin-1-induced tonic contraction (pA(2)=8.80 and 6.55, respectively) and increase in intraluminal pressure (pA(2)=8.68 and 7.02, respectively), while they did not affect endothelin-1-induced inhibition of spontaneous activity. Endothelin 1 produces increase in tone and intraluminal pressure of isolated human ureter acting on both ET(A) and ET(B) receptors, the first one being functionally more important. Only endothelins 1 and 3 inhibit spontaneous, phasic activity of human ureter, but this effect was not blocked by selective antagonists of ET(A) and ET(B) receptors.

Role of papaverine hydrochloride administration in patients with intractable renal colic: randomized prospective trial

OBJECTIVES

To evaluate the therapeutic effect of papaverine hydrochloride in the treatment of patients with renal colic pain unresponsive to conventional treatment.

METHODS

From March 2007 to January 2008, a total of 561 patients with severe renal colic pain due to a ureteral stone were treated with conventional agents (hyoscine-N-butylbromide and diclofenac sodium) in the emergency and urology departments. Of these 561 patients, 110, with no response to the treatment and persistent severe pain, were randomized into 3 groups for additional treatment. The patients in group 1 (n = 37) received intravenous hyoscine-N-butylbromide, those in group 2 (n = 37) received papaverine hydrochloride, and those in group 3 (n = 36) received pethidine. Before and after treatment, all patients completed a visual analog scale (VAS) questionnaire, with a scale of 0 (no pain) to 10 (maximal complaint), to measure their subjective pain. The mean VAS score of each group was compared with that of the other groups.

RESULTS

The pretreatment mean VAS scores of all 3 groups were not significantly different statistically from each other (4.02 +/- 1.20, 4.36 +/- 1.97, and 4.27 +/- 1.50; P > .05). However, after treatment, the mean VAS scores of the patients treated with papaverine (0.93 +/- 0.29) and pethidine (0.81 +/- 0.38) were significantly different from those of the hycosine group (3.67 +/- 2.21; P < .001). However, the mean VAS scores of groups 2 and 3 were comparable (P = .67). Unlike opioids, no papaverine-related severe side effects were observed.

CONCLUSIONS

Our results indicate that papaverine hydrochloride can used in an effective manner in the management of renal colic pain in patients unresponsive to commonly used conventional agents.

[Diagnosis and therapy of acute ureteral colic]

Acute ureteral colic presents with a complex of acute and characteristic flank pain that usually indicates the presence of a stone in the urinary tract. Diagnosis and management of renal colic have undergone considerable evolution and advancement in recent years. The application of noncontrast helical computed tomography (CT) in patients with suspected ureteral colic is one major advance in the primary diagnostic process. The superior sensitivity and specificity of helical CT allow ureterolithiasis to be diagnosed without the potential side effects of contrast media. Initial management is based on three key concepts: (A) rational and fast diagnostic process (B) effective pain control (C) and understanding of the impact of stone location and size on the natural course of the disease and definitive urologic management. These concepts are discussed in this review with reference to contemporary literature.

Epidemiology and risk factors in urolithiasis

Stone formation in the urinary tract affects about 5-10% of the population in industrialized countries, although it is very rare in other countries such as Greenland or Japan. The high incidence and recurrence rate contribute to making the urolithiasis a serious social problem. Nowadays, urolithiasis must be considered a 'disease in evolution' for several reasons, such as epidemiological changes, evolution of the methods used for diagnosis, and the treatment and prophylaxis of the population considered 'at risk' of stone disease. Some features of stone disease have changed over the last few years due to many social, economical and cultural factors that are described here. The increased prevalence of small urinary calculi has brought about a change in clinical symptoms, with frequent episodes of renal-ureteral colic, persistent pain and hydronephrosis. Similarly, the presence of residual fragments after extracorporeal shock wave lithotripsy has induced a radical change in the management of small calculi through the use of mini-invasive surgical techniques.

Temporal changes in renal endoglin and TGF-beta1 expression following ureteral obstruction in rats

Chronic renal disease is characterized by the accumulation of extracellular matrix proteins in the kidney and a loss of renal function. Tubulointerstitial fibrosis has been reported to play an important role in the progression of chronic renal diseases. Transforming growth factor-beta1 (TGF-beta1) is a profibrotic cytokine playing a major contribution to fibrotic kidney disease. Endoglin is a membrane glycoprotein of the TGF-beta1 receptor system. The aim of this work was to determine the time-course expression of renal type I and IV collagens, endoglin and TGF-beta1 in a rat model of induced tubulointerstitial fibrosis at 1, 3, 10 and 17 days after unilateral ureteral obstruction (UUO). In 17 days-ligated (L)-renal samples, a marked interstitial fibrosis was detected by Masson's trichromic and Sirius red staining, accompanied by an increase in type I collagen expression as shown by immunohistochemical analysis. Northern blot studies revealed a progressive increase in collagen alpha2(I), TGF-beta1 and endoglin mRNA expression in L kidneys when compared with the corresponding non-ligated (NL) kidneys from the animals subjected to left UUO. Seventeen days after UUO, significant increases in collagen alpha2(I), collagen alpha1(IV), TGF-beta1 and endoglin mRNA levels were detected in L kidneys vs NL kidneys. Significantly higher levels of the protein endoglin were found in L kidneys than in NL kidneys 10 and 17 days following obstruction. A marked increase expression for endoglin and TGF-beta1 was localized in renal interstitium by immunohistochemical studies 17 days after obstruction. In conclusion, this work reports the upregulation of endoglin coincident to that of its ligand TGF-beta1 in the kidneys of rats with progressive tubulointerstitial fibrosis induced by UUO.

Cólico renal: Revisión de la literatura y evidencia científica

In recent years diagnosis and treatment of acute renal colic have changed thanks to the introduction of new radiological procedures that allow with high reliability to establish obstructive cause and a better treatment. In the other hand, there are multiple clinical studies that show the most effective treatments for acute crisis. The aim of this revision is to update the diagnostic and therapeutic aspects of renal colic which were modified recently, and allowed to break some classic concepts without scientific evidence.