Time to stone passage for observed ureteral calculi: a guide for patient education

Urgent shock wave lithotripsy as first-line treatment for ureteral stones: a meta-analysis of 570 patients

The rationale for the use of immediate shock wave lithotripsy (SWL) after a renal colic episode is to obtain maximum stone clearance in the shortest possible time with associated early detection of lithotripsy failures which can be treated with auxiliary procedures. The aim of this meta-analysis is to understand the role of this treatment option in the emergency setting as first-line treatment and to compare such an immediate procedure to a delayed one in terms of stone-free and complication rates. A bibliographic search covering the period from January 1995 to September 2010 was conducted in PubMed, MEDLINE and EMBASE. Database searches yielded 48 references. This analysis is based on the seven studies that fulfilled the predefined inclusion criteria. A total of 570 participants were included. The number of participants in each survey ranged from 16 to 200 (mean 81.42). Six studies were published after 2000 and one in the 1990s. All studies reported participants' age with mean of 40.9 years, and range between 11 and 88 years. All patients presented with unilateral lithiasis, as such the number of total stones treated was 570. Mean stone diameter ranged between 6.38 and 8.45 mm. According to the logistic regression applied stone-free rates were 79 % (61-95) for the proximal ureter, 78 % (69-88) for the mid ureter, 79 % (74-84) for the distal ureter and 78 % (75-82) for overall. Stone-free rates do not evidence a statistically significant difference compared to those described in the AUA and EAU guidelines for elective management. SWL management of ureteral stones in an emergency setting is completely lacking in the international guidelines and they results disperse in the literature in few works. According to our meta-analysis, immediate SWL for a stone-induced acute renal colic seems to be a safe treatment with high success rate. This evidence will be validated by further randomized studies, with a larger series of patients.

Factors that predict the spontaneous passage of ureteric stones in children

Objective

To study the natural history of stone passage in children with ureterolithiasis and to define factors predictive of spontaneous passage.

Patients and methods

In all, 72 children with ureteric stones were evaluated; patients with ureteric calculi of >10 mm were excluded, as were those with absolute indications for surgical stone removal. Stone size, location, side, presence of hydronephrosis, perinephric stranding and degree of the tissue-rim sign were estimated by unenhanced helical computed tomography (UHCT). All patients were sent home with no administration of an α-blocker. The stone status was evaluated by a plain abdominal film or CT at ≈6 weeks after the initial diagnostic evaluation. The time from the initial complaint to the passage of the stone was recorded for each patient.

Results

In all, 54 (75%) children with ureteric stones of ⩽6 mm eventually passed their stones spontaneously. However, stones of <4 mm and those in the distal ureter had a significantly higher spontaneous passage rate and shorter time to stone passage (P < 0.05). The UHCT findings of a higher degree of the tissue-rim sign, hydronephrosis and perinephric fat stranding were associated with a lower likelihood of stone passage.

Conclusions

The rate of spontaneous passage of ureteric stones in children varies with stone location, and perinephric stranding on UHCT seems to be useful for predicting the possibility of spontaneous passage. In cases with unfavourable signs an early intervention might have better outcomes than conservative therapy.

Minimally Invasive Surgical and Medical Management of Urinary Calculi

Management of urinary calculi has changed from open pyelolithotomy and ureterolithotomy to predominantly non-invasive procedures such as extracorporeal shockwave lithotripsy (ESWL) as well as endourological such as ureterorenoscopy (URS) and percutaneous nephrolithotripsy (PCNL). Technology has advanced rapidly allowing stone disease to be treated with minimally invasive techniques that have lower morbidity than the open operations of the past. Newer semi-rigid ureteroscopes of size 7 to 9 F allow visualisation of the ureter without traumatic dilatation. There is the flexible ureteroscope developed with smaller fibre optics, the addition of the working channel that allows the use of laser fibres for stone fragmentation and a greater deflection of the tip that enables all parts of the pelvicalyceal system to be inspected for stones. New generation lithotripters for ESWL deliver shockwave to a smaller focal zone so as to minimise damage to surrounding soft tissue but as a result, there are higher failure rates. PCNL, though more invasive than ESWL and URS, is the procedure of choice for large renal stones. It is highly efficient in such situations as newer equipment to disintegrate stone and newer techniques for percutaneous access has been developed. In addition to all these minimally invasive surgical techniques, there is medical therapy available to allow the expulsion of distal ureteric stones as well as alkalinising agents to dissolve uric acid stones. Metabolic evaluation is necessary for patients with recurrent stones. Dietary adjustments may help prevent recurrent stone formation in selected patients depending on the results. With all these techniques currently available, management of urinary calculi has to be tailored according to the size, location of stone as well as patient preference.

Comparison and efficacy of low-dose and standard-dose tamsulosin and alfuzosin in medical expulsive therapy for lower ureteral calculi: prospective, randomized, comparative study

PURPOSE

Typically in Korea, for a standard dose (0.4 mg) of tamsulosin, two low doses (0.2 mg) are administered. The aim of this study was to evaluate and compare the efficacy of tamsulosin (0.2 mg and 0.4 mg) and alfuzosin (10 mg) in the treatment of lower ureteral stones.

MATERIALS AND METHODS

A total of 141 patients presenting with a single 4- to 10-mm sized lower ureteral stone were randomly assigned to 4 groups. Patients in group 1 (n=41) and group 2 (n=30) received an oral dose of 0.2 mg tamsulosin once and twice daily, respectively, and patients in group 3 (n=36) received a daily oral dose of 10 mg alfuzosin. Patients in group 4 (n=34) received trospium chloride only. The spontaneous passage of stones, the stone expulsion time, and adverse effects were evaluated.

RESULTS

There were no significant differences in patient background, including age, sex, BMI, stone size, stone side, and symptom duration. The spontaneous stone passage rate through the ureter was higher and the stone expulsion time was faster in groups 1, 2, and 3 than in group 4. There were no statistically different changes in groups 1, 2, and 3. The adverse effects observed in all groups were comparable and were mild.

CONCLUSIONS

Tamsulosin at 0.2 mg and 0.4 mg and alfuzosin (10 mg) proved to be safe and effective. A first cycle of medical expulsive therapy with tamsulosin 0.2 mg could be considered as an option in the management of single lower ureteral stone.

TOF-SIMS study of cystine and cholesterol stones

Two different human stones, cystine and cholesterol from the kidney and gall bladder, were examined by time-of-flight secondary ion mass spectrometry using Ga(+) primary ions as bombarding particles. The mass spectra of kidney stone were compared with those measured for the standard compounds, cystine and cysteine. Similar spectra were obtained for the stone and cystine. The most important identification was based on the existence of the protonated molecules [M + H](+) and deprotonated molecules [M-H](-). The presence of cystine salt was also revealed in the stone through the sodiated cystine [M + Na](+) and the associated fragments, which might be due to the patient treatment history. In the gallstone, the deprotonated molecules [M-H](+) of cholesterol along with relatively intense characteristic fragments [M-OH](+) were detected.

Comparison of conventional radiography combined with ultrasonography versus nonenhanced helical computed tomography in evaluation of patients with renal colic

The aim of this study is to determine whether kidneys ureters bladder X-ray (KUB) film combined with ultrasound (US) can be effectively used in evaluation of renal colic and miss stones with clinically significant size identified on nonenhanced computed tomography (NECT) in patients with urolithiasis. This retrospective study evaluated the clinical and radiological records of 300 patients at our institution undergoing KUB and/or US and/or NECT for the evaluation of renal colic from June 2007 to December 2010. Of patients with negative findings on KUB and/or US, 22 had renal stones on NECT (mean size 4.4 mm, range 3-8), 3 had lower ureteral stone (mean size 3.3 mm, range 2-5). In patients with isolated suspicious renal ectasia without stone image, two had renal stone on NECT (mean size 4 mm, range 2-6), 5 had upper ureteral stone (mean size 4.4 mm, range 4-6), 7 had middle ureteral stone (mean size 3.7 mm, range 3-4) and 14 had lower ureteral stone (mean size 4 mm, range 2-6). The cost-effective and almost radiation-free combination of KUB and US should be preferred for diagnosis of urolithiasis, as it detects most of the ureteral and renal calculi which are clinically significant.

Role of white blood cell and neutrophil counts in predicting spontaneous stone passage in patients with renal colic

OBJECTIVE

To determine the clinical, imaging and laboratory variables that can predict spontaneous passage of ureteral stones causing renal colic and the role of white blood cell (WBC) and neutrophil counts for the prediction of spontaneous calculi passage.

PATIENTS AND METHODS

A total of 156 patients who were referred to the emergency department complaining of renal colic due to a ureteral stone entered the analysis. Several clinical, laboratory and imaging parameters were evaluated for their potential ability to predict stone passage in a time interval of 1 month. The study design had two objectives. Primarily we analyzed all patients irrespective of stone size and secondly we analyzed patients with calculi of 10 mm maximum length.

RESULTS

Spontaneous stone passage was observed in 96 (61.5%) patients in the overall population and in 84 (65.1%) of 129 patients with calculi <10 mm. Increased concentrations of serum WBCs and neutrophils at the time of the acute phase of a renal colic were associated with increased likelihood of spontaneous passage. In the multivariate analyses we found that WBC and neutrophil counts were the most important predictors of stone elimination.

CONCLUSIONS

Active surveillance of patients suffering from ureteral lithiasis is an acceptable option. Identifying the parameters which can predict those patients who will mostly benefit from this is of great importance. Based on our results, WBC and neutrophil counts should be considered when patients with renal colic secondary to ureteral calculi are evaluated since they can significantly add to spontaneous elimination prediction. Their consideration in addition to other important factors, like stone size and location, would maximize their predictive ability.

A 970 Hounsfield units (HU) threshold of kidney stone density on non-contrast computed tomography (NCCT) improves patients' selection for extracorporeal shockwave lithotripsy (ESWL): evidence from a prospective study

What's known on the subject? and What does the study add? Stone density on non-contrast computed tomography (NCCT) is reported to be a prognosis factor for extracorporeal shockwave lithotripsy (ESWL). In this prospective study, we determined that a 970 HU threshold of stone density is a very specific and sensitive threshold beyond which the likelihood to be rendered stone free is poor. Thus, NCCT evaluation of stone density before ESWL may useful to identify which patients should be offered alternative treatment to optimise their outcome.

OBJECTIVE

• To evaluate the usefulness of measuring urinary calculi attenuation values by non-contrast computed tomography (NCCT) for predicting the outcome of treatment by extracorporeal shockwave lithotripsy (ESWL).

PATIENTS AND METHODS

• We prospectively evaluated 50 patients with urinary calculi of 5-22 mm undergoing ESWL. • All patients had NCCT at 120 kV and 100 mA on a spiral CT scanner. Patient age, sex, body mass index, stone laterality, stone size, stone attenuation values (Hounsfield units [HU]), stone location, and presence of JJ stent were studied as potential predictors. • The outcome was evaluated 4 weeks after the ESWL session by NCCT. • ESWL success was defined as patients being stone-free (SF) or with remaining stone fragments of <4 mm, which were considered as clinically insignificant residual fragments (CIRF).

RESULTS

• Our survey concluded that 26 patients (52%) were SF, 12 (24%) had CIRF and 12 (24%) had residual fragment on NCCT after a one ESWL treatment. • Stones of patients who became SF or had CIRF had a lower density compared with stones in patients with residual fragments [mean (sd) 715 (260) vs 1196 (171) HU, P < 0.001]. • The Youden Index showed that a stone density of 970 HU represented the most sensitive (100%) and specific (81%) point on the receiver-operating characteristic curve. • The stone-free rate for stones of <970 HU was 96% vs 38% for stones of ≥ 970 HU (P < 0.001). A linear relationship between the calculus density and the success rate of ESWL was identified.

CONCLUSION

• The use of NCCT to determine the attenuation values of urinary calculi before ESWL helps to predict treatment outcome, and, consequently, could be helpful in planning alternative treatment for patients with a likelihood of a poor outcome from ESWL.

Current practices in the management of patients with ureteral calculi in the emergency room of a university hospital

OBJECTIVE

Urinary lithiasis is a common disease. The aim of the present study is to assess the knowledge regarding the diagnosis, treatment and recommendations given to patients with ureteral colic by professionals of an academic hospital.

MATERIALS AND METHODS

Sixty-five physicians were interviewed about previous experience with guidelines regarding ureteral colic and how they manage patients with ureteral colic in regards to diagnosis, treatment and the information provided to the patients.

RESULTS

Thirty-six percent of the interviewed physicians were surgeons, and 64% were clinicians. Forty-one percent of the physicians reported experience with ureterolithiasis guidelines. Seventy-two percent indicated that they use noncontrast CT scans for the diagnosis of lithiasis. All of the respondents prescribe hydration, primarily for the improvement of stone elimination (39.3%). The average number of drugs used was 3.5. The combination of nonsteroidal anti-inflammatory drugs and opioids was reported by 54% of the physicians (i.e., 59% of surgeons and 25.6% of clinicians used this combination of drugs) (p = 0.014). Only 21.3% prescribe alpha blockers.

CONCLUSION

Reported experience with guidelines had little impact on several habitual practices. For example, only 21.3% of the respondents indicated that they prescribed alpha blockers; however, alpha blockers may increase stone elimination by up to 54%. Furthermore, although a meta-analysis demonstrated that hydration had no effect on the transit time of the stone or on the pain, the majority of the physicians reported that they prescribed more than 500 ml of fluid. Dipyrone, hyoscine, nonsteroidal anti-inflammatory drugs, and opioids were identified as the most frequently prescribed drug combination. The information regarding the time for the passage of urinary stones was inconsistent. The development of continuing education programs regarding ureteral colic in the emergency room is necessary.

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.

Dual-energy dual-source CT with additional spectral filtration can improve the differentiation of non-uric acid renal stones: an ex vivo phantom study

OBJECTIVE

The purpose of this study was to determine the ex vivo ability of dual-energy dual-source CT (DSCT) with additional tin filtration to differentiate among five groups of human renal stone types.

MATERIALS AND METHODS

Forty-three renal stones of 10 types were categorized into five primary groups on the basis of effective atomic numbers, which were calculated as the weighted average of the atomic numbers of constituent atoms. Stones were embedded in porcine kidneys and placed in a 35-cm water phantom. Dual-energy DSCT scans were performed at 80 and 140 kV with and without tin filtration of the 140-kV beam. The CT number ratio, defined as the ratio of the CT number of a given material in the low-energy image to the CT number of the same material in the high-energy image, was calculated on a volumetric voxel-by-voxel basis for each stone. Statistical analysis was performed, and receiver operating characteristic (ROC) curves were plotted to compare the difference in CT number ratio with and without tin filtration, and to measure the discrimination among stone groups.

RESULTS

The CT number ratio of non-uric acid stones increased on average by 0.17 (range, 0.03-0.36) with tin filtration. The CT number ratios for non-uric acid stone groups were not significantly different (p > 0.05) between any of the two adjacent groups without tin filtration. Use of the additional tin filtration on the high-energy x-ray tube significantly improved the separation of non-uric acid stone types by CT number ratio (p < 0.05). The area under the ROC curve increased from 0.78 to 0.84 without fin filtration and to 0.89-0.95 with tin filtration.

CONCLUSION

Our results showed better separation among different stone types when additional tin filtration was used on dual-energy DSCT. The increased spectral separation allowed a five-group stone classification scheme. Some overlapping between particular stone types still exists, including brushite and calcium oxalate.

The efficacy of tamsulosin in lower ureteral calculi

Context:

There has been a paradigm shift in the management of ureteral calculi in the last decade with the introduction of new less invasive methods, such as ureterorenoscopy and extracorporeal shock wave lithotripsy (ESWL).

Aims:

Recent studies have reported excellent results with medical expulsive therapy (MET) for distal ureteral calculi, both in terms of stone expulsion and control of ureteral colic pain.

Settings and Design:

We conducted a comparative study in between watchful waiting and MET with tamsulosin.

Materials and Methods:

We conducted a comparative study in between watchful waiting (Group I) and MET with tamsulosin (Group II) in 60 patients, with a follow up of 28 days.

Statistical Analysis:

Independent 't' test and chi-square test.

Results:

Group II showed a statistically significant advantage in terms of the stone expulsion rate. The mean number of episodes of pain, mean days to stone expulsion and mean amount of analgesic dosage used were statistically significantly lower in Group II (P value is 0.007, 0.01 and 0.007, respectively) as compared to Group I.

Conclusions:

It is concluded that MET should be considered for uncomplicated distal ureteral calculi before ureteroscopy or extracorporeal lithotripsy. Tamsulosin has been found to increase and hasten stone expulsion rates, decrease acute attacks by acting as a spasmolytic, reduces mean days to stone expulsion and decreases analgesic dose usage.

Emergency management of ureteral stones: Recent advances

Most ureteral stones can be observed with reasonable expectation of uneventful stone passage. When an active ureteral stone treatment is warranted, the best procedure to choose is dependent on several factors, besides stone size and location, including operators’ experience, patients’ preference, available equipment and related costs. Placement of double-J stent or nephrostomy tube represents the classical procedures performed in a renal colic due to acute ureteral obstruction when the conservative drug therapy does not resolve the symptoms. These maneuvers are usually followed by ureteroscopy or extracorporeal shockwave lithotripsy, which currently represent the mainstay of treatment for ureteral stones. In this review paper a literature search was performed to identify reports dealing with emergency management of renal colic due to ureteral stones. The main aspects related to this debated issue are analyzed and the advantages and disadvantages of each treatment option are carefully discussed.

Medical expulsive therapy using alfuzosin for patient presenting with ureteral stone less than 10mm: a prospective randomized controlled trial

OBJECTIVES

To assess the spontaneous passage rate for patients being treated with alfuzosin 10mg daily after presenting with an acute ureteral stone compared with a control group, and to assess the respective pain control status.

METHODS

This was a prospective randomized controlled trial. Patients presenting with an acute ureteral stone (size 5-10mm) were enrolled and randomized into a medical expulsive therapy (MET) group or control group. The MET group received alfuzosin slow release (SR) 10mg daily for 4weeks and dologesic (paracetamol+dextropropoxyphene, four tablets daily on demand) for 2weeks. The control group received the same analgesics for 2weeks only. Diclofenac sodium SR 100mg daily for 2weeks was added in case of suboptimal pain control. All the patients were assessed through phone interview at week 2 and with kidney-ureter-bladder X-ray at week 5 to check for any evidence of stone passage.

RESULTS

A total of 67 patients were included in the analysis. The overall spontaneous passage rate was increased by 31.8% with MET (P=0.006). For an upper ureteral stone, the rate was increased by 51.3% (P=0.01). The MET group used significantly less dicolofenac sodium (1.5 tablets vs 6.7 tablets, P=0.031).

CONCLUSIONS

MET using alfuzosin SR 10mg daily is effective to enhance the ureteral stone spontaneous passage rate, particularly for upper ureteral stones. Fewer analgesic drugs are consumed and more patients can avoid ureteroscopic lithotripsy and/or extracorporeal shock wave lithotripsy.

Predictors for spontaneous stone passage in patients with renal colic secondary to ureteral calculi

OBJECTIVES

To determine the clinical, laboratory, and imaging variables that can predict spontaneous stone passage in patients with renal colic secondary to ureteral calculi.

METHODS

We prospectively analyzed the medical records of 114 patients who admitted to the emergency department for renal colic from June until November of 2010. Forty-six of them were excluded. The presence of ureteral calculi was confirmed by either a kidney-ureter-bladder plain film or an ultrasound or a computer tomography. In all patients, a second visit after 1 month was planned and the stone status was checked by the same imaging techniques.

RESULTS

From the 68 patients, 16 had a calculus in the upper ureter, 10 in the mid ureter, and 42 in lower part. Stone size was ranged from 2.3 to 15 mm, 52.9% of them were located in the left ureter and 51.5% were radiopaque. Stones passed spontaneously in 36 patients. In multivariate analysis, serum white blood cell count found to be the most significant predictor (P = 0.028) for spontaneous passage followed by stone size (P = 0.037). In analysis of patients with stone size <10 mm, left side (P = 0.017) and serum white blood cell count (P= 0.032) found to be significant predictors.

CONCLUSIONS

Serum white blood cell count is an easy to assay variable in everyday practice. This study showed that its value, at the acute phase of a renal colic, is a significant predictor for stone spontaneous passage and should be considered. Stone size remains a valuable predictor. Stones <10 mm on the left ureter have a higher likelihood to pass spontaneously.

Randomized controlled trial of the efficacy of isosorbide-SR addition to current treatment in medical expulsive therapy for ureteral calculi

It has been suggested that nitrates are potent smooth muscle relaxants that may reduce pain and facilitate ureteral stone passage; therefore it may be an option for medical expulsive therapy in ureteral stones. In a prospective randomized controlled clinical trial, we evaluated the efficacy of medical expulsive therapy with isosorbide-SR 40 mg in patients with ureteral stones (≤10 mm). The patients with ureteral stones in KUB or urinary tract ultrasonography were randomized to receive methylprednisolone plus celecoxib without (control group), and with isosorbide-SR 40 mg (treatment group) for 21 days. 66 patients [33(50%) in control, 33(50%) in treatment group] were entered randomly to our study. The stone expulsion rate was not significantly different between two groups (54.5 vs. 45.5%) (P = 0.497). The need for surgical procedures were more common in control group within 21 days (9.4 vs. 6.1%) and more common in treatment group after 21 days (33.3 vs. 21.9%) (P = 0.756).Patients in the treatment group experienced more intractable pain (27.3 vs. 6.1%), intractable vomiting (3 vs. 0%) (P = 0.046) and hospitalization (3 vs. 0%) (P = 0.314). Drug side effects including headache and dizziness were more common in treatment group (39.4 vs. 9.1%) (P = 0.004). In our study, the use of isosorbide-SR in treatment group did not improve the stone expulsion rate in patients with ureteral stones (≤10 mm) but developed more side effects. Then it may not an appropriate alternative for medical expulsive therapy. Of course, further trials are recommended.

Tamsulosin as an expulsive therapy for steinstrasse after extracorporeal shock wave lithotripsy: a randomized controlled study

OBJECTIVE

Steinstrasse is a well-known complication following extracorporeal shockwave lithotripsy (ESWL). The objective of this study was to evaluate the efficacy of tamsulosin as a management of steinstrasse.

MATERIAL AND METHODS

88 patients with unilateral steinstrasse were treated between January 2005 and December 2008. The patients were randomly allocated into two equal groups. There were no significant differences between groups for age, gender, stone location, stone length or stone fragment size (p > 0.05). Patients in group 1 (study group) received a single daily morning dose of tamsulosin (0.4 mg) for a maximum of 4 weeks, in addition to pain-relieving therapy. Patients in group 2 (control group) received only the pain-relieving therapy. All patients were checked weekly with a plain X-ray of the urinary tract, urinary ultrasonography, urine analysis and serum creatinine. Pain episodes, day of spontaneous stone expulsion, total analgesic dosage and drug side-effects were recorded.

RESULTS

Stone expulsion occurred in 32 of the 44 patients (72.7%) receiving tamsulosin and in 25 of the 44 patients (56.8%) in the control group. Patients receiving tamsulosin had a significantly higher stone expulsion rate (p = 0.017). There were no significant differences between groups for mean stone expulsion time or number of analgesics used. Twelve patients (27.3%) in the group receiving tamsulosin and 19 patients (43.3%) in the control group needed hospitalization; the group difference was statistically significant (p = 0.017).

CONCLUSIONS

When compared with no treatment, tamsulosin can significantly facilitate expulsion of retained ureteral stone fragments following ESWL.

The Role of Non-Steroidal Anti-Inflammatory Drugs in Renal Colic

NSAIDs provide optimal analgesia in renal colic due to the reduction in glomerular filtration and renal pelvic pressure, ureteric peristalsis and ureteric oedema. Prevention of glomerular afferent arteriolar vasodilatation renders these patients at risk of renal impairment. NSAIDs have the additional benefit of reducing the number of new colic episodes and preventing subsequent readmission to hospital. Despite recent work promoting the use of pharmacological agents to improve stone passage rates, NSAIDs do not appear to reduce the time to stone passage or increase the likelihood of stone passage in renal colic.

Can the degree of hydronephrosis on ultrasound predict kidney stone size?

OBJECTIVE

The aim of the study was to determine if the degree of hydronephrosis on focused emergency renal ultrasound correlates with kidney stone size on computed tomography.

METHODS

A retrospective study was performed on all adult patients in the emergency department who had a focused emergency renal ultrasound and ureterolithiasis on noncontrast computed tomography. Severity of hydronephrosis was determined by the performing physician. Ureteral stone size was grouped into 5 mm or less and larger than 5 mm based on likelihood of spontaneous passage.

RESULTS

One hundred seventy-seven ultrasound scans were performed on patients with ureteral calculi. When dichotomized using test characteristic analysis, patients with none or mild hydronephrosis (72.9%) were less likely to have ureteral calculi larger than 5 mm than those with moderate or severe hydronephrosis (12.4% vs 35.4%; P < .001) with a negative predictive value of 0.876 (95% confidence interval, 0.803-0.925).

CONCLUSION

Patients with less severe hydronephrosis were less likely to have larger ureteral calculi.

Chronic kidney disease affects the stone-free rate after extracorporeal shock wave lithotripsy for proximal ureteric stones

OBJECTIVE

To investigate the effect of renal function on the stone-free rate (SFR) of proximal ureteric stones (PUS) after extracorporeal shock wave lithotripsy (ESWL), as urinary obstruction caused by PUS can impair renal function, and elevated serum creatinine levels are associated with decreased ureteric stone passage.

PATIENTS AND METHODS

From January 2005 to December 2007, 1534 patients had ESWL for urolithiasis, 319 having ESWL in situ for PUS; they were reviewed retrospectively. Patients requiring simultaneous treatment of kidney stones, placement of a double pigtail stent, or percutaneous pigtail nephrostomy tube were excluded. We divided patients into groups by chronic kidney disease (CKD) stage according to the estimated glomerular filtration rate (eGFR) of ≥ 60 and <60 mL/min/1.73 m(2). Stone-free status was defined as no visible stone fragments on a plain abdominal film at 3 months after ESWL. A logistic regression model was used to evaluate the possible significant factors that influenced the SFR of PUS after ESWL, and to develop a prediction model.

RESULTS

The overall SFR of PUS (276/319 patients) was 86.5%; the SFR was 93% in patients with an eGFR of ≥ 60 and 50% in those with an eGFR of <60 (P < 0.001). After univariate and multivariate analysis, the three significant factors affecting SFR were an eGFR of ≥ 60, stone width, and gender, with odds ratios (95% confidence intervals) of 19.54 (8.25-46.30) (P < 0.001), 0.67 (0.55-0.82) (P < 0.001) and 0.16 (0.05-0.50 (P = 0.002), respectively. A logistic regression model was developed to estimate the probability of SFR after ESWL, the equation being 1/(1 + exp [-(3.8137 - 0.3967 × (stone width) + 2.9724 × eGFR - 1.8120 × Male)]), where stone width is the observed value (mm), eGFR = 1 for eGFR ≥ 60 and 0 for <60, and male = 1 for male, 0 for female.

CONCLUSIONS

Gender, eGFR ≥ 60 and a stone width of >7 mm were significant predictors affecting the SFR after one session of ESWL for PUS.

Impact of hydronephrosis on treatment outcome of solitary proximal ureteral stone after extracorporeal shock wave lithotripsy

The purpose of this study was to investigate the impact of hydronephrosis on the treatment outcome of patients with a solitary proximal ureteral stone after extracorporeal shock wave lithotripsy (ESWL). A total of 182 consecutive patients who underwent ESWL for a solitary proximal ureteral stone of between 5 and 20 mm in size in our institution were included in this study. The degree of hydronephrosis was defined by renal ultrasonography. Patient data, stone size, shock wave numbers and shock wave energy were also recorded. Treatment outcome was evaluated 3 months after the first session of ESWL. In multivariate analysis, only the maximal stone length (odds ratio [OR], 0.15; 95% confidence interval [CI], 0.03-0.91; p = 0.04) and the degree of hydronephrosis (OR, 0.40; 95% CI, 0.16-0.98; p = 0.045) were significant predicting factors for stone-free status 3 months after ESWL. For stones < or = 10 mm, the stone-free rate decreased from 80% in patients with mild hydronephrosis to 56.4% in those with moderate to severe hydronephrosis. For stones > 10 mm, the stone-free rate decreased further, from 65.2% in patients with mild hydronephrosis to 33.3% in those with moderate to severe hydronephrosis. In summary, patients with a solitary proximal ureteral stone and a stone > 10 mm, the treatment outcome after ESWL was not good if moderate to severe hydronephrosis was noted on ultrasonography. Alternative treatments, such as ureteroscopic lithotripsy, may be appropriate as initial treatment or after failure of one session of ESWL.

Pediatric urolithiasis: clinical predictors in the emergency department

OBJECTIVE

The objective of this study was to identify factors that predict the presence of urolithiasis detected with unenhanced computed tomography (UCT) in children.

METHODS

A retrospective study of all subjects <21 years of age who presented to the emergency department at Akron Children's Hospital and underwent UCT of the abdomen between January 2002 and December 2005 was performed. Demographic, clinical, diagnostic, treatment, and disposition data were abstracted by using a standardized form. Univariate and logistic regression analyses of factors associated with urolithiasis were performed.

RESULTS

A total of 339 eligible patients were identified, with 110 cases of urolithiasis detected with UCT for 95 individual patients. The mean age of the study patients was 14.4 years; 72 patients (66%) were female. In 17 cases (15%) of urolithiasis, initial urinalysis results were negative for blood. Fifty-seven stones (51.8%) were ureteral, 26 (23.6%) were renal, and 4 (3.6%) were in the bladder. Among children who did not have a stone identified through UCT, 23 cases (10%) of potentially significant, alternative diagnoses were identified. A history of urolithiasis, a history of nausea and vomiting, the presence of flank pain on examination, and >2 red blood cells per high-power field in urine microscopy were positively associated with urolithiasis. A history of fever or dysuria and costovertebral angle tenderness on physical examination were inversely associated with urolithiasis on UCT scans.

CONCLUSIONS

UCT plays an important role in the diagnostic evaluation of children with flank pain. Approximately 15% of children with urolithiasis do not have hematuria.

Celecoxib in the management of acute renal colic: a randomized controlled clinical trial

OBJECTIVES

To evaluate the efficacy of celecoxib as an analgesic and medical expulsive agent in acute renal colic.

METHODS

A prospective randomized double-blind study was conducted on patients presenting with an obstructing ureteral calculus < 10 mm in largest diameter. Patients were randomized to 400 mg of celecoxib, followed by 200 mg every 12 hours for 10 days, or to placebo. Patients with a solitary kidney, renal insufficiency (CR > 1.8), urinary tract infection, or significant cardiovascular disease were excluded.

RESULTS

A total of 57 patients provided consent of which 53 completed the study. Four patients were excluded from the analysis because of stone passage or withdrawal of consent before the first dose of study medication. No significant difference was noted in the spontaneous stone passage rate (celecoxib 55.2%, placebo 54.2%) and between celecoxib and placebo with regard to days to stone passage (7.0 vs 9.0, P = .6) or size of stone passed (3.9 vs 4.6 mm, P = .18). No significant difference was noted in pain analog scores (2.6 vs 3.5, P = .71) or narcotic doses (13.2 vs 13.6, P = .74). Furthermore, a 25% decrease in narcotic use (or 19 mg based on placebo mean) was outside the 80% one-sided confidence interval for the change in mean narcotic use between the 2 groups. Thus, it is unlikely (< 20%) that we missed a clinically significant beneficial effect of celecoxib on narcotic consumption because of sample size.

CONCLUSIONS

Celecoxib does not facilitate stone passage or decrease narcotic requirements in patients with acute renal colic.

Ureteral stones due to systemic mastocytosis: diagnostic and therapeutic characteristics

Urolithiasis is expected to cause a considerable complication in patients with systemic mastocytosis. The aim of the present report is to demonstrate that due to pathological activation and irritability of mast cells, special features in the diagnostic investigation and therapy of urolithiasis have to be considered in patients with systemic mastocytosis. The clinical presentation, diagnostic investigation and therapeutic procedure of urolithiasis in a patient with systemic mastocytosis are described. Urolithiasis may be a significant complication of systemic mastocytosis. Non-contrast CT is the main tool for diagnosing urolithiasis after a detailed history and clinical exam. Patients with systemic mastocytosis should receive a premedication composed of a glucocorticoid and H(1)- and H(2)-histamine receptor antagonists. An increased vulnerability of mucosal tissues is expected in patients with systemic mastocytosis that may limit the options of operative and postoperative therapy. Opioids should be used cautiously for analgesia in patients with systemic mastocytosis.