Physiological Hydronephrosis Research Articles

Physiological hydronephrosis: an underestimated cause of abdominal pain during pregnancy

Physiological hydronephrosis: an underestimated cause of abdominal pain during pregnancy

The Management of Symptomatic Hydronephrosis in Pregnancy.

The aim of this article is to provide a literature review on the management of symptomatic physiological hydronephrosis in pregnancy and compare different modalities of intervention when needed. In this review, we conducted an electronic literature search of peer-reviewed journal articles. The PubMed, Research Gate, and Google Scholar databases were queried with the following search terms: "pregnancy", "obstruction," and "hydronephrosis"; the terms "urolithiasis" and "kidney stone" were excluded. As a result, conservative treatment was successful and more favored for most of the patients and the clinicians in the different studies we found. Conservative management will usually include regular analgesia, positioning, and antibiotics. Close follow-up with ultrasound is always recommended. Intervention with ureteric stent insertion or nephrostomy tube insertion was less favored and only triggered by certain clinical criteria. In conclusion, symptomatic hydronephrosis in pregnancy can be safely treated conservatively. However, ureteral double-J stenting or percutaneous nephrostomy are effective and safe treatment methods in the minority of patients with persistent symptoms not responding to conservative management.

Clinical Course of Pregnant Women with Maternal Hydronephrosis: Retrospective Clinical Study

Aim: The study aims to investigate the clinical course of symptomatic physiological hydronephrosis in pregnant women and the results of treatment in patients required treatment. Material and Methods: A hundred and two consecutive pregnant women who presented with clinical signs and symptoms related to the upper urinary system were included in the study. Renal ultrasonography, urinalysis, serum creatinine levels, white blood cell count, and urine culture were done in all patients at the first visit and repeated at least once a month until 1 month after delivery. In patients with acute pyelonephritis, urinalysis was repeated every 3 days until white blood cell count, erythrocyte sedimentation rate and C-reactive protein levels normalized; urine culture and kidney ultrasonography were performed monthly until 1 month after delivery. Conservative measures (positioning, analgesia, antibiotics) were used in all patients with symptomatic physiological hydronephrosis. If the patient's condition was resistant to medical treatment and the degree of hydronephrosis was increased, drainage was performed by inserting a double J stent into the ureter. Results: Conservative treatments were successful in 98 (96.1%) of 102 patients, but 4 (3.9%) had signs and symptoms of acute pyelonephritis progressing to urosepsis. Antibiotics were continued in patients who developed pyelonephritis, symptoms regressed rapidly, signs of kidney infection returned to normal. Follow-up pregnancies ended with normal vaginal delivery. Conclusion: Symptomatic hydronephrosis in pregnancy can be treated conservatively, should be treated carefully and patients should be followed up. However, ureteral double-J stenting is an effective and safe treatment method in patients with resistant symptoms.

Ultrasound evaluation for prediction of outcomes and surgical decision in fetal hydronephrosis.

Fetal hydronephrosis (HY) is a frequent congenital condition, which may be detected by prenatal ultrasound. Society for Fetal Urology (SFU) and anterior-posterior diameter (APD) grading are two major grading systems based on ultrasonography. The present study aimed to assess the predictive value of the SFU and APD grades in patients with fetal HY. A total of 162 patients with 234 kidneys affected by HY were included in the present study. The SFU and APD grades were determined from the ultrasound images at 38 gestational weeks, and a 12-month follow-up was performed after birth. The associations of the SFU and APD grades with the outcome of fetal HY, including HY regression, and post-partum surgery were examined. In the present study, 16 patients with 17 kidneys were diagnosed with pathological HY, and stenosis at the ureteropelvic junction was demonstrated to be a leading cause of pathological HY. Among the 234 kidneys affected by HY, 161 kidneys were scored as SFU grade I, 57 as SFU grade II, 7 as SFU grade III and 9 kidneys as SFU grade IV. According to the APD grading system, 112 kidneys were determined as having low, 104 as having moderate and 18 as having severe HY. The SFU and APD grades were demonstrated to be independently associated with the occurrence of pathological HY by logistic regression analysis with a high diagnostic accuracy to distinguish pathological and physiological HY cases as evidenced by the results of ROC analysis. In addition, univariate and multivariate logistic regression analysis indicated that patients with spontaneous HY regression usually had low SFU and APD grades. Furthermore, the rate of surgery was increased in the group of patients with high SFU or APD grades, and these two systems were identified as independent predictors for the requirement of surgery by Kaplan-Meier analysis. Patients with pathological HY had high SFU and APD grades, and these two grading systems may be used as reliable predictors for the outcome of fetal HY, including HY regression, and post-partum surgery.

Assessment of hydronephrosis in obstetrics and gynaecology patients: Most useful application of MR urography

Assessment of hydronephrosis in obstetrics and gynaecology patients: Most useful application of MR urography - IJOGR- Print ISSN No: - 2394-2746 Online ISSN No:- 2394-2754 Article DOI No:- 10.18231/2394-2754.2019.0011, Indian Journal of Obstetrics and Gynecology Research-Indian J Obstet Gynecol Res

Nephrolithiasis in Pregnancy

Nephrolithiasis is a common condition that practicing urologists will encounter and manage. The pregnant patient presents unique challenges when it comes to the diagnosis and treatment of stones. Altered anatomy and physiology, considerations of the fetus, and various imaging and procedural contraindications make navigating the care of pregnant patients with nephrolithiasis more complex than that of the general population. This review presents an algorithmic approach to the diagnosis and management of nephrolithiasis in the pregnant patient. Certain areas that are highlighted include diagnostic imaging modalities and the pros and cons of each with regard to the pregnant patient. Also discussed in detail are various treatment options, including medical management and available surgical interventions. As renal colic is the most common reason for nonobstetric hospitalization in pregnant women, it is important that they are managed with a multidisciplinary approach. This review contains 2 highly rendered figures, 4 tables, and 26 references Key words: low-dose CT, medical expulsive therapy, nephrolithiasis, obstructive hydronephrosis, percutaneous nephrostomy, physiologic hydronephrosis, pregnancy, renal colic, resistive index, ureteral stent, ureteroscopy

Nephrolithiasis in Pregnancy

Nephrolithiasis is a common condition that practicing urologists will encounter and manage. The pregnant patient presents unique challenges when it comes to the diagnosis and treatment of stones. Altered anatomy and physiology, considerations of the fetus, and various imaging and procedural contraindications make navigating the care of pregnant patients with nephrolithiasis more complex than that of the general population. This review presents an algorithmic approach to the diagnosis and management of nephrolithiasis in the pregnant patient. Certain areas that are highlighted include diagnostic imaging modalities and the pros and cons of each with regard to the pregnant patient. Also discussed in detail are various treatment options, including medical management and available surgical interventions. As renal colic is the most common reason for nonobstetric hospitalization in pregnant women, it is important that they are managed with a multidisciplinary approach. This review contains 2 highly rendered figures, 4 tables, and 26 references Key words: low-dose CT, medical expulsive therapy, nephrolithiasis, obstructive hydronephrosis, percutaneous nephrostomy, physiologic hydronephrosis, pregnancy, renal colic, resistive index, ureteral stent, ureteroscopy

Initially Asymmetrical Function on MAG3 Renography Increases Incidence of Adverse Outcomes

To discriminate pathological from physiological hydronephrosis (99m)Tc-mercaptoacetyltriglycine (MAG3) diuretic renography is a fundamental imaging modality. Initial asymmetrical differential function or decreasing function on serial MAG3 scans is a classic surgical indication. However, prognostic evidence supporting this is limited. Therefore, we examined the association between initial function and outcomes. We hypothesized that patients with initially asymmetrical function would have higher odds of functional decline, and experience symptoms and surgical intervention compared to patients with initially symmetrical scans. We retrospectively reviewed the charts of 1,124 pediatric patients with hydronephrosis seen at Stollery Children's Hospital from 2000 to 2014. A total of 387 cases of unilateral ureteropelvic junction obstruction were grouped by initial postnatal differential function with asymmetrical defined as a greater than 10% difference in relative function. Postnatal surveillance, followup MAG3 results, pyeloplasty rates and post-pyeloplasty outcomes were compared. Of 387 patients 143 (37%) had initially asymmetrical function. Of those undergoing MAG3 scan surveillance 17% experienced a 10% or greater decline in ipsilateral differential function vs a 6% rate of function loss in the initially symmetrical group (OR 3.2, 95% CI 1.6-6.4, p = 0.0008). The overall pyeloplasty rate in patients with asymmetrical and symmetrical function was 27% and 16%, respectively (OR 1.9, 95% CI 1.1-3.2, p = 0.013). Patients with initially asymmetrical function had an increased rate of pyeloplasty secondary to symptoms compared to those with initially symmetrical function (16% vs 8%, OR 2.1, 95% CI 1.1-4.0, p = 0.019). Mean time to functional decline and pyeloplasty was 19and 17 months, respectively. Patients with initially asymmetrical differential function had increased ORs for subsequent renal decline, symptom onset and pyeloplasty.

Imaging of stone disease in pregnancy

Renal colic is the most frequent non-obstetric cause for abdominal pain and subsequent hospitalization during pregnancy. Intervention is necessary in patients who do not respond to conservative treatment. Ultrasound (US) is widely used as the first-line diagnostic test in pregnant women with nephrolithiasis, despite it is highly nonspecific and may be unable to differentiate between ureteral obstruction secondary to calculi and physiologic hydronephrosis. Magnetic resonance imaging (MRI) should be considered as a second-line test, when US fails to establish a diagnosis and there are continued symptoms despite conservative management. Moreover, MRI is able to differentiate physiologic from pathologic dilatation. In fact in the cases of obstruction secondary to calculi, there is renal enlargement and perinephric edema, not seen with physiological dilatation. In the latter, there is smooth tapering of the middle third of the ureter because of the mass effect between the uterus and adjacent retroperitoneal musculature. When the stone is lodged in the lower ureter, a standing column of dilated ureter is seen below this physiological constriction. MRI is also helpful in demonstrating complications such as pyelonephritis. In the unresolved cases, Computed tomography remains a reliable technique for depicting obstructing urinary tract calculi in pregnant women, but it involves ionizing radiation. Nephrolithiasis during pregnancy requires a collaboration between urologists, obstetricians, and radiologists.

Half Fourier Single-shot Turbo Spin-echo Magnetic Resonance Urography for the Evaluation of Suspected Renal Colic in Pregnancy

To report our experience with magnetic resonance urography (MRU) in pregnant women suspected of having obstructing upper tract calculi. The diagnosis of an upper tract calculus in the pregnant woman can be challenging. Recent evidence suggests that MRU can be used to effectively evaluate renal colic. From 2008-2011, 9 pregnant women were referred for evaluation of suspected renal colic caused by an obstructing upper tract stone. All patients underwent MRU with a half Fourier single-shot turbo spin-echo (HASTE) protocol. Medical records and imaging studies were reviewed for demographic and clinical data as well as outcome measures. The mean age of the subjects was 25 years (range 20-34); average gestational age of the fetus was 23 weeks (range 9-36). In all cases, a renal ultrasound was the initial imaging study obtained, with nondiagnostic findings. HASTE MRU detected 4 ureteral stones and 4 cases of physiological hydronephrosis of pregnancy. In one case, interpretation of the MRU was limited as a result of patient motion. Of the patients with obstructing stones, 1 required endourologic management during her pregnancy and 3 were followed conservatively. No adverse events related to MRU occurred. HASTE MRU is an informative imaging study for pregnant women with suspected upper tract stone disease. Information gathered from this study augments that gained from alternative modalities, and aids in medical decision-making. The lack of ionizing radiation exposure, coupled with the capture of detailed anatomic imaging, makes HASTE MRU a particularly useful study in this setting.

Renal Colic in Pregnancy: Lithiasis or Physiological Hydronephrosis?

To assess the reliability and accuracy of diagnostic investigations in differentiating urinary calculi from physiological hydronephrosis as the cause of renal colic. The appropriateness and efficacy of the treatments used were was also examined. A retrospective review of 300 consecutive patients presenting to 2 local hospitals was carried out. Descriptive and correlational data on clinical presentation, diagnostic imaging, and interventions undertaken were analyzed. A total of 262 patients were included in the final analysis. Most clinical or laboratory features were unhelpful in predicting the presence of a stone. Left-sided colic was more likely to indicate presence of stone (64.9% vs 46.6%, P = .003). The accuracy of ultrasound findings in predicting presence of stone improved (from 56.2% to 71.9%) when features of obstruction, such as ureteric jet absence and an elevated resistive index (RI), were included in the assessment. Spontaneous resolution occurred in a smaller proportion of patients with stone (63% vs 85%, P <.001). The need for intervention was more prevalent in patients with stones (29.2% vs 5.9%, P <.001). Stent insertion was the most common intervention and was usually completed successfully (95.5%). Ureteroscopy was safe and resulted in stone retrieval 88% of the time. Most clinical signs and symptoms are unhelpful in determining the cause of colic symptoms. Left-sided colic is more likely to represent the presence of a stone. An enhanced ultrasound examination is a reasonably accurate initial study. The standard endoscopic interventions are more likely to be used in colic cases because of actual calculi, and are safe and effective throughout pregnancy.

Editorial Comment

The practice of live renal donation remains a competition between minimization of the risk to the healthy donor and the ease of reimplantation of the donated kidney. One of the bedrock principles underpinning the practice of live renal donation is leaving the donor with the better kidney, whenever a discrepancy exists between the 2. If both are equal, the left kidney is generally preferred by recipient surgeons owing to the increased length and often thicker wall of the renal vein compared with the right. This facilitates reanastomosis to the iliac vessels, especially in recipients with a deep pelvis or a high body mass index. However, the wide application of laparoscopic donor nephrectomy has created strong incentives to bend these rules. Before laparoscopy, about 30%-40% of donor kidneys were right kidneys. Some even advocated the preferential use of right kidneys in fertile women, to avoid the possibility of physiologic hydronephrosis of pregnancy. With widespread laparoscopic nephrectomy, only 5%-10% of donor kidneys are the right kidney. 1 Wright T.A. Wilt T.A. Holt D.R. et al. Laparoscopic living donor nephrectomy: a look at current trends and practice patterns at major transplant centers across the United States. J Urol. 2008; 179: 1488-1492 Abstract Full Text Full Text PDF PubMed Scopus (44) Google Scholar In addition to the anatomic reasons mentioned, laparoscopic surgeons are reluctant to remove a cuff of vena cava with the right donor kidney, preferring to divide the right renal vein with a staple line on several millimeters of vein. This makes the right donor kidney less desirable for transplantation. When decisions are made regarding which kidney to remove, the ease of laparoscopy often becomes the primary consideration. Why We Did Not Use Left Side for This DonorUrologyVol. 74Issue 1PreviewWe describe a case of an unusual variation of the double retroaortic left renal vein discovered during routine donor examination of the abdomen by multidetector computed tomography. A 53-year-old man underwent evaluation in our department as a potential renal donor for his brother who had end-stage renal failure. Multidetector computed tomography angiography showed double retroaortic left renal veins. This can increase the potential for serious morbidity and mortality in the donor. We prefer right kidney for potential donation. Full-Text PDF ReplyUrologyVol. 74Issue 1PreviewI would like to thank Stuart M. Flechner, who is one of the eminent researchers of this issue, for his interpretations and comments on our article. Right donor nephrectomy is reserved for instances in which the left kidney is determined to be unacceptable for transplantation. The indications most often cited are multiple left renal arteries or veins, anomalous left anatomy, smaller right kidney, or a cystic mass in the right kidney.1,2 In our case, the diethylenetriamine pentaacetic acid-determined glomerular filtration rate of the left kidney was 68.85 mL/min/1.73 m2 and that of the right kidney was 45.78 mL/min/1.73 m2. Full-Text PDF

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

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. 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. 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. 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.

Evaluation of Painful Hydronephrosis in Pregnancy:: Magnetic Resonance Urographic Patterns in Physiological Dilatation Versus Calculous Obstruction

We evaluated magnetic resonance urography (MRU) appearances in symptomatic hydronephrosis in pregnancy and compared urographic patterns in physiological and calculous disease. A total of 24 consecutive pregnant women with symptomatic hydronephrosis underwent MRU, comprising an overview fast T2-weighted examination of the abdomen and pelvis, and thick slab, heavily T2-weighted MRU images, followed by focused, high resolution T2-weighted sequences obtained in an axial and coronal oblique plane through the level of ureteral caliber change. Of these 24 pregnant women 15 were found to have physiological hydronephrosis, 7 had calculous disease and 2 had preexisting urinary anomalies. MRU findings in physiological hydronephrosis cases were extrinsic compression of the middle third of the ureter, no filling defect and a collapsed ureter below it. Obstruction by ureteral calculi was seen at points of ureteral narrowing in the ureter, that is at the vesicoureteral junction in 2 cases, in the compressed mid ureter in 3 and at the pelviureteral junction in 1. Nonobstructive renal calculi were seen in another patient. Calculi presented throughout pregnancy but physiological hydronephrosis presented only in the late second and third trimesters. With distal calculi the MRU appearance was the double kink sign with constriction at the pelvic brim and the vesicoureteral junction with a standing column of urine in the pelvic ureter. There was renal edema and perirenal extravasation. Small calculi were only identified using high resolution T2-weighted magnetic resonance imaging. MRU is a valuable and well tolerated investigation for evaluating painful hydronephrosis in pregnancy. There are characteristic and differing urographic appearances in physiological and calculous obstruction.

Symptomatic Physiologic Hydronephrosis in Pregnancy

Objective: We present the incidence and results of treatment of symptomatic physiologic hydronephrosis in 3,400 pregnant women. Methods: We analyzed 103 consecutive women who presented with clinical signs and symptoms related to the upper urinary system. Renal sonography, urinalysis, serum creatinine levels, white blood cell (WBC) count, and urine culture were done in all patients at first visit and repeated at least once a month until 1 month after delivery. In patients who manifested acute pyelonephritis, urinalysis, WBC count, erythrocyte sedimentation rate and C–reactive protein levels were repeated every 3 days until normalization, and urine culture as well as renal sonography were performed once a week until 1 month after delivery. Conservative measures (positioning, analgesia, antibiotics) were performed in all patients with symptomatic physiologic hydronephrosis. If the patient’s condition was refractory to medical management, drainage of the ureter with a double pigtail stent was performed. Results: Conservative measures were successful in 97 (94%) of 103 patients but 6 (6%) patients had ongoing signs and symptoms of acute pyelonephritis progressing to urosepsis. In all of them, antibiotics were continued and a double pigtail stent was placed resulting in fast regression of symptoms, curing of renal infection and progresse of the pregnancies to the term with vaginal delivery. Conclusions: Symptomatic hydronephrosis in pregnancy can be treated conservatively. If the patient’s condition is refractory to medical management, an internal drainage with double pigtail stent may be necessary.

Acute renal failure in pregnancy.

Acute renal failure (ARF) during pregnancy is a rare event. However, the care of the woman diagnosed with ARF is a challenge for the perinatal care team. The physiologic hydronephrosis and hydroureter of pregnancy alters clinical parameters for assessing the woman diagnosed with ARF. Urinary stasis and enhanced filtration predisposes to alterations in 24-hour urine evaluations, increased urinary creatinine excretion, and lower BUN and serum creatinine values. If the renal system becomes compromised, the woman is at risk for acidemia, fluid and electrolyte imbalances, and pregnancy compromise. The perinatal nurse must have an understanding of normal pregnancy physiology and an appreciation for how pregnancy physiology may alter renal assessments. Furthermore, the nurse must know the impact that ARF can have on maternal status and fetal well-being. Astute, continuous assessments of maternal and fetal status are required to detect subtle changes. While maternal status is the primary concern, it must not be forgotten that a change in fetal status may be the first indication of underlying maternal compromise.

Sonographic Visualization of the Ureter in Pregnancy

We describe a method of differentiating physiological from pathological dilatation of the renal collecting system in pregnant patients. In physiological hydronephrosis the dilated ureter extends down only to the level of the common iliac artery. In 2 patients with distal ureteral stones a dilated ureter was visualized past the vessels.To determine the frequency and reliability of visualizing the ureters in pregnant patients 105 consecutive asymptomatic pregnant patients were examined. Hydronephrosis was found in 83 kidneys in 59 of the patients. The dilated ureter was visualized in 64 of the renal units. The anatomy was well demonstrated by color flow Doppler scanning and in all of these cases the dilated ureter was seen to taper where it crossed the common iliac artery. These results suggest that the presence of a dilated ureter past the iliac artery is strong evidence for pathological distal ureteral obstruction in pregnancy.

Prevalence and clinical implications of hypocalcemia in acutely ill patients in a medical intensive care setting: Dasai TK Carlson RW, Geheb MA. Am J Med 1988; 84:209–214

Prevalence and clinical implications of hypocalcemia in acutely ill patients in a medical intensive care setting: Dasai TK Carlson RW, Geheb MA. Am J Med 1988; 84:209–214

Aetiological factors in the genesis of pregnancy hydronephrosis.

In order to identify possible aetiological factors in the genesis of physiological hydronephrosis in pregnancy, the degree of pelvic-calyceal dilatation in 90 asymptomatic pregnant women was correlated with levels of plasma oestradiol, progesterone, 24-hour urinary oestriol, the site of the placenta, birthweight of the fetus, and pelvic inlet measurements. A grading system based on maximum calyceal diameter was used; 90% of the patients were found to have at least mild dilatation on the right side. No correlation was demonstrated between the degree of hydronephrosis and the levels of oestradiol, progesterone and 24-hour urinary oestriol excretion. The birth-weight of the fetus and its relationship with the pelvic inlet measurements also did not correlate with the occurrence of hydronephrotic changes in the kidneys. The only significant positive finding was a higher incidence of moderate and severe hydronephrosis occurring in patients with a right-sided placenta than compared with the left (x2 = 4.77; p less than 0.05), although the sensitivity and specificity in predicting hydronephrosis from a right-sided placenta is low (53% and 66% respectively). Our results support the hypothesis of a mechanical aetiology in the genesis of pregnancy hydronephrosis, where vascular compression on the ureters may be an important contributory factor. Our study has also shown that urinary tract infection and reduction of creatinine clearance were not more common in patients with moderate or severe pelvic-calyceal dilatation.

Pregnancy hydronephrosis--a longitudinal ultrasonic evaluation.

The progression of physiological hydronephrosis through the 3 trimesters of pregnancy was assessed by ultrasonic measurement of calyceal diameters in 56 asymptomatic patients in a longitudinal study. A grading system basing on the maximum calyceal diameter was used; 89% of the patients showed at least mild dilatation before delivery. There was a preponderance of the right side being affected. In 6 patients (10.7%), severe dilatation was demonstrable and in all of them its onset appeared to be in the second trimester. The likelihood of progression to moderate or severe dilatation when only mild dilatation is demonstrated in the second trimester is low. Furthermore, it is not common for moderate dilatation in the second trimester to progress to severe dilatation in the third trimester. These findings appear to support the mechanical theory in the genesis of pregnancy hydronephrosis. Rapid regression of calyceal dilatation is not apparent in the first 5 days after delivery.