Comparison of stone size and response to analgesic treatment in predicting outcome of patients with renal colic

CT imaging history for patients presenting to the ED with renal colic--evidence from a multi-hospital database

Background

Patients with renal colic have a 7% chance of annual recurrence. Previous studies evaluating cumulative Abbreviations: computed tomography (CT) exposure for renal colic patients were typically from single centers.

Methods

This was an observational cohort study. Inner-city ED patients with a final diagnosis of renal colic were prospectively identified (1/10/16–10/16/16). Authors conducted structured electronic record reviews from a 6-hospital system encompassing over 192,000 annual ED visits. Categorical data analyzed by chi-square; continuous data by t-tests. Primary outcome measure was the proportion of study group patients with prior history CT abdomen/pelvis CT.

Results

Two hundred thirteen patients in the study group; 59% male, age 38+/− 10 years, 67% Hispanic, 62% prior stone history, flank pain (78%), dysuria (22%), UA (+) blood (75%). 60% (95% CI = 53–66%) of patients received an EDCV CT; hydronephrosis seen in 55% (95% CI = 46–63%), stone in 90%(95% CI = 83–94%). No significant differences observed in the proportion of EDCV patients who received CT with respect to: female vs. male (62% vs. 56%; p = 0.4), mean age (37+/− 9 years vs. 39+/− 11 years; p = 0.2), and Hispanic vs. non-Hispanic white (63% vs.63%; p = 0.96). Patients with a prior stone history were more likely than those with no history to receive an EDCV CT (88% vs. 16%; p < 0.001). 118 (55%; 95% CI = 49–62%) of patients had at least one prior CT, 46 (22%; 95% CI = 16–28%) had ≥3 prior CTs; 29 (14%; 95% CI = 10–19%), ≥ 10 prior CTs. Patients who did not receive an EDCV CT had a significantly higher mean prior number of CTs than those who had EDCV CT (5.1+/− 7.7 vs 2.2+/− 4.9; p < 0.001). Patients with prior stone were more likely to receive only U/S during EDCV (33% vs. 15%; p = 0.003).

Conclusions

Within our EDCV cohort of renal colic patients, 55% had at least one prior CT. The mean number of prior CTs was lower for patients receiving CT on EDCV, and Ultrasound (US) alone was used more often in patients with prior stone history vs. those with no prior history.

Assessment of factors affecting the spontaneous passage of lower ureteric calculus on the basis of lower ureteric calculus diameter, density, and plasma C- reactive protein level

Introduction:

The study aimed to evaluate the factors which affect the spontaneous passage of lower ureteric calculus on the basis of noncontrast computed tomography kidneys, ureters, and bladder (NCCT KUB) stone diameter, stone density, and plasma C-reactive protein (CRP) level.

Materials and Methods:

We conducted a prospective study of 200 patients with lower ureteric calculus 5–10 mm in size, from October 2015 to December 2016. All patients underwent NCCT KUB region with a 5 mm axial and reformatted coronal section. Edema just above the calculus and rim sign at the level of calculus and density of calculus is evaluated. Only scan with isolated, unilateral, solitary ureteric calculus was included in the final analysis and monitored up to 4 weeks, and plasma CRP is estimated in all patients to determine the clinical outcome.

Results:

A total of 200 patients (145 males, 55 females; mean age ± standard deviation, 34.73 ± 10.29) were included in the study. Lower ureteric calculus between 5–7 mm passed in 70% and 7–10 mm passed in 40%. There was 18% underestimation of maximum stone diameter in axial plane as compared to coronal plane. For spontaneous passage of calculus, craniocaudal (CC) diameter is more reliable then axial in NCCT. Rim sign and edema is absent in 64% of those passed spontaneous calculus. CRP level more than 2.45 mg/dl has low spontaneous expulsion rate. The stone with different HU passes through the ureter with same rate.

Conclusion:

Plasma CRP level and CC diameter and absence of rim sign on NCCT KUB are more reliable factors then density for spontaneous passage of ureteric calculus.

Bayesian comparative assessment of diagnostic accuracy of low-dose CT scan and ultrasonography in the diagnosis of urolithiasis after the application of the STONE score

OBJECTIVE

The objective of our study was to assess the diagnostic quality of low-dose computed tomography (CT) when compared to ultrasound (US) in diagnosis of urolithiasis using STONE score as a predictor of pre-test probability and the Bayesian statistical model to calculate post-test probabilities (POST) for both diagnostic tests.

METHODS

STONE score was used to form risk groups to obtain pre-test probabilities. Likelihood ratios (LR) were calculated from external data for low-dose CT and US. POST were obtained using pre-test probabilities and likelihood ratios with Bayesian nomogram. Absolute (ADG) and relative (RDG) gains in diagnostic value were calculated.

RESULTS

Calculated +LR for US was 12 and -LR was 0.32; for CT, +LR was 19 and -LR 0.04. +LR and low STONE for US yielded POST 57% and RDG 470%; intermediate STONE POST 92% and RDG 84%; and high STONE POST 99% and RDG 10%. -LR and low STONE for US POST 3% and RDG -70%; intermediate POST 24% and RDG -52%; and high STONE POST 74% and RDG -17.7%. +LR and low STONE for CT POST 68% and RDG 580%; moderate STONE POST 95% and RDG 90%; and high STONE POST 99% and RDG 10%. -LR and low STONE for CT POST 0% and RDG -100%; intermediate POST 4% and RDG -92%; and high STONE POST 26% and RDG -71.1%. ANOVA calculations comparing CT vs US for +LR showed no statistical significance (P value = 0.9893; LR- P value = 0.5488).

CONCLUSION

Bayesian statistical analysis demonstrated slight superiority of CT scan over US on STONE score low- and moderate-risk stratified subtypes, whereas no significant advantage was seen when evaluating high-probability patients.

[CLINICAL FACTORS ASSOCIATED WITH SPONTANEOUS PASSAGE OF URETER STONES IN CONSERVATIVE MANAGEMENT: 6 mm IN MAXIMAL STONE SIZE MEASURED BY ULTRASONOGRAPHY CAN BE A PREDICTIVE BORDER]

(Purpose) To date there was no consensus regarding expectant size of stone and time to expulsion in the conservative treatment of ureter stones. The aim of this study was to find the clinical factors associated with stone passage by evaluating the outcome of ureter stones with expectant management in Japanese. (Materials and methods) A total of 679 ureter stone cases who visited our hospital with acute real colic and/or hematuria between 2009 and 2013, and who had decided to be treated by expectant management with or without medical expulsive therapy were enrolled in this study. All cases were examined size, location and presence of stone, and degree of hydronephrosis with ultrasonography. The examined data plus clinical data such as gender, age, side and body mass index were analyzed to find the factors related to spontaneous passage of ureter stones. Statistical analysis was performed to predict whether the factors were associated with the ureteral stone expulsion or not. (Results) Accumulated residual stone curve using Kaplan-Meier method showed time to 50%-expulsion as 15.7 days in cases with stone size no more than 6.0 mm and that as 21.8 days in those with greater than 6.0 mm, and time to 50%-expulsion as 28.8 days in cases with upper ureter stone whereas 15.6 days in those with middle or distal ureter stone. Analysis in groups with 1 mm-interval in stone size showed statistical significance only when compared 5-6 mm group with 6-7 mm group in size. Multivariate analysis showed stone size and location as statistically significant and independent factors to predict time to expulsion within 30 days. (Conclusion) Stone size and location was statistically reconfirmed to be associated with spontaneous passage in expectant management of ureter stones. This study statistically demonstrated the possibility that 6 mm in maximal stone size measured by ultrasonography can be a predictive border. 75% of ureter stones within 6 mm in maximal size measured by ultrasonography may expect to be expelled within 30 days.

Expectant Management of Ureter Stones: Outcome and Clinical Factors of Spontaneous Passage in a Single Institution's Experience

Purpose

The aim of this study was to evaluate the outcome of ureter stones with expectant management and the clinical factors associated with stone passage in Koreans.

Materials and Methods

We reviewed the charts of patients who visited the emergency room or urological office of our institution with acute renal colic between 2001 and 2008. A total of 656 ureter stone formers were enrolled in this study who had decided to be treated by expectant management. Clinical data such as gender, age, size and location of the stone, body mass index, and previous stone history were analyzed to find the factors related to spontaneous passage of ureter stones.

Results

Of the 656 ureter stones, 566 stones (86.3%) were spontaneously expelled. Mean duration of follow-up was 17.5 days (range, 1 to 100 days). Mean time to stone passage was 6.8 days for stones less than 2 mm in size, 12.6 days for stones 2 to 4 mm, 14.8 days for stones 4 to 6 mm, and 21.8 days for stones 6 to 8 mm (p<0.001). The cumulative spontaneous passage rate was 55.3% in 7 days, 73.7% in 14 days, 88.5% in 28 days, and 97.7% in 60 days after the first attack. A total of 90 patients (13.7%) required interventions because of symptom relapse or renal deterioration that was related to the location and size of the stone (each, p<0.001). The more proximal the location and the larger the stone was than 6 mm, the less the chance of spontaneous passage (each, p<0.001).

Conclusions

Size and location of ureter stones are the most important factors for predicting the spontaneous passage of the stone. If a patient has a distal ureter stone of less than 6 mm in size, it is acceptable for the urologist to observe for spontaneous passage for 2 months.

Predicting intervention in renal colic patients after emergency department evaluation

OBJECTIVES

There is no set of prospectively validated criteria to identify the emergency department (ED) patients with renal colic who are most likely to eventually have to undergo an intervention. This study prospectively assessed predictors of intervention in this patient population.

METHODS

This prospective cohort study included adult patients with renal colic who presented to 2 tertiary care hospital EDs. Patients had an 18-variable data form completed by an emergency physician and a radiological study to confirm urolithiasis. After discharge, patients were followed at 1 and 4 weeks to assess for intervention. The outcome criteria included the patient having had at least 1 of the following procedures performed: extracorporeal shockwave lithotripsy (ESWL), ureteroscopy, percutaneous nephrostomy or open surgery. Data were analyzed using appropriate univariate techniques, and those variables associated with intervention were combined using logistic regression analysis.

RESULTS

Over an 8-month period, 245 patients with confirmed urolithiasis were followed; 20% (95% confidence interval [CI] 15%-25%) eventually had a procedure to remove their calculi. Three variables were significantly correlated with having a procedure: i) size of calculus >or= 6 mm (odds ratio [OR] 10.7, 95% CI 4.6-24.8), ii) location of calculus above mid-ureter (OR 6.9, 95% CI 3.0-15.9), and iii) Visual Analogue Scale score for pain at discharge from the ED >or= 2 cm (OR 2.6, 95% CI 1.0-6.8). The area under receiver operating characteristic curve was 0.77 (95% C I 0.70-0.84) (p < 0.001). If all variables were present there was a 90% probability of the patient having an intervention performed within 4 weeks of discharge from the ED. Conversely, if none of the variables were present there was only a 4% probability of an intervention. Overall, the model had a sensitivity of 92% (95% CI 89%-96%) and a specificity of 63% (95% CI 57%-69%).

CONCLUSIONS

This study has identified variables that could potentially be used to identify those renal colic patients who require an intervention after ED evaluation. Future studies will prospectively validate this model.

Predictive role of renal resistance indices in the extracorporeal shock-wave lithotripsy outcome of ureteral stones

OBJECTIVE

Doppler ultrasonography (US) can be used to measure renal blood flow and calculate resistance indices. Increased renal resistance indices have been suggested to be associated with upper urinary tract obstruction and may help clinical physicians to differentiate physiological hydronephrosis from urinary tract obstruction. The aims of this study were to investigate the value of renal resistance indices before extracorporeal shock-wave lithotripsy (ESWL) and to determine whether they were predictive of the ESWL outcome.

MATERIAL AND METHODS

Between May 2005 and May 2006, a total of 84 patients who suffered from ureteral stones with renal colic and were treated with ESWL in the emergency department were enrolled in this study. Blood urea nitrogen and serum creatinine were determined and urinalysis, abdominal plain film X-ray and color Doppler US were performed. The resistive index (RI) and pulsatility index (PI) of the three different measurements of renal upper, middle and lower poles were calculated for both the affected and contralateral kidneys.

RESULTS

Sixty of the 84 patients were found to be stone-free after follow-up, and the total stone-free rate was 71%. There was a statistically significant difference between the mean RI of the affected and contralateral kidneys in all patients: 0.672+/-0.046 vs 0.616+/-0.054 (p<0.001). Moreover, there were statistically significant differences between the stone-free group and the residual stone group regarding the RI (0.651+/-0.046 vs 0.723+/-0.029, respectively; p=0.003) and PI (1.143+/-0.162 vs 1.262+/-0.145, respectively; p=0.03) of the affected kidney.

CONCLUSIONS

Intrarenal resistance indices represent the integration of arterial compliance, pulsatility, and peripheral resistance. Higher pre-ESWL resistance indices correlate with lower ESWL treatment success rates. Doppler US performed before ESWL treatment can therefore aid in making a correct clinical decision.

Cumulative CT Exposures in Emergency Department Patients Evaluated for Suspected Renal Colic

Computed tomography (CT) is the diagnostic standard in Emergency Department evaluation of suspected renal colic but delivers substantial radiation. We determined the frequency of CT scan in suspected renal colic, diagnosis and outcome, and cumulative CT scans per patient. A retrospective chart review with waiver of informed consent was conducted. A total of 356 patient encounters were reviewed from January to October 2003. Mean age was 39 years. Seventy-four percent included a CT scan, with 38% normal, 58% showing urolithiasis, and 1% showing emergent etiologies. Six percent of patients undergoing CT were admitted for urolithiasis, and 6% had a urologic procedure within 7 days. Sixteen percent of patients did not have a CT scan, and 79% underwent two or more CT scans. Emergency Department patients presenting with symptoms suggesting renal colic are likely to undergo CT on multiple occasions. Radiation exposures from repeated CT scans are substantial, and a clinical decision rule for this scenario is needed.

Mode of presentation and first line of management of non-recurrent urolithiasis in Kuwait

AIMS

To determine the incidence, mode of presentation, first line of management and composition of non-recurrent urolithiasis in Kuwait.

METHODS

Consecutive patients admitted between January 1999 and December 2002 with non-recurrent urolithiasis were prospectively analyzed.

RESULTS

The average annual incidence of hospital admission for non-recurrent urolithiasis in Kuwait was 43.44 per 100,000 population, representing men and women (ratio, 9:1) with a median age of 41.91 years. Of the hospital admissions for non-recurrent urolithiasis, 57.2% of cases were acute. Overall, the most predominant symptom was flank pain, while the least common symptom was acute urinary retention. Ureteroscopic stone manipulation was the most common initial treatment modality in the present series, as it was utilized in 43.3% and 37.09% for patients admitted on elective and emergency basis, respectively. Of the calculi available for chemical analysis, 91% contained calcium, 73% contained calcium oxalate, 17% contained mixed calcium and 1% contained calcium phosphate. The composition of the rest of the stones were urate in 7%, struvite in 1% and cystine in 1%.

CONCLUSIONS

Urolithiasis is a common disease in the Kuwait region that mainly presents with flank pain. Ureteroscopic calculus removal is the most common modality of treatment. The majority of the calculi seen in Kuwait contained calcium.