Management of blunt renal trauma on pre-existing diseased kidneys: a cross-sectional study

Pathological kidney trauma is a special entity. Congenital or acquired lesions may interfere with clinical presentation, radiological imaging, and the therapeutic approach.

Objective

Our objective was to determine the clinical, radiological, and therapeutic features of this entity.

Materials and methods

The medical records of 37 observations were retrospectively collected from January 1992 to February 2022. All cases were explored by a kidney ultrasound and/or a computed tomography scan, and classified according to the American Association of Surgery of Trauma. Pre-existing renal abnormalities were found in 37 patients among 203 (18.2%). The most common underlying lesion were urolithiasis (37.8%) followed by pyelo-ureteral junction syndrome (32.4%). Surgical abstention was decided in 11 cases, four nephrectomies were performed as a matter of urgency, and seven nephrectomies were performed remotely. The cure of uropathy was performed after an average delay of 3 months.

Conclusion

Kidneys with underlying pathology are habitually more susceptible to trauma. Contusions are often benign contrasting with a high nephrectomy rate.

Inflammation triggered by the NLRP3 inflammasome is a critical driver of diabetic bladder dysfunction

Diabetes is a rapidly expanding epidemic projected to affect as many as 1 in 3 Americans by 2050. This disease is characterized by devastating complications brought about high glucose and metabolic derangement. The most common of these complications is diabetic bladder dysfunction (DBD) and estimates suggest that 50-80% of patients experience this disorder. Unfortunately, the Epidemiology of Diabetes Interventions and Complications Study suggests that strict glucose control does not decrease ones risk for incontinence, although it does decrease the risk of other complications such as retinopathy, nephropathy and neuropathy. Thus, there is a significant unmet need to better understand DBD in order to develop targeted therapies to alleviate patient suffering. Recently, the research community has come to understand that diabetes produces a systemic state of low-level inflammation known as meta-inflammation and attention has focused on a role for the sterile inflammation-inducing structure known as the NLRP3 inflammasome. In this review, we will examine the evidence that NLRP3 plays a central role in inducing DBD and driving its progression towards an underactive phenotype.

Kidney Efficiency Index - quantitative parameter of a dynamic renal scintigraphy. I. Theory and preliminary verification

BACKGROUND

One of the basic clinical indications for dynamic renal scintigraphy (DRS) is a diagnosis of obstructive uropathy and/or nephropathy. Currently, a basic quantitative criterion for diagnosing nephropathy is the percentage of individual kidney's contribution in the global uptake of a radiopharmaceutical from the blood (so-called Split Function - SF). From a clinical point of view, a parameter evaluating a radiopharmaceutical uptake and reflecting the efficiency of a specific kidney, determined independently of the total uptake of both kidneys, would be much more useful. Based on a Rutland theory, a kidney uptake constant K proportional to a radiotracer uptake by individual kidney was introduced and applied to DRS with 99mTc-ethylene-1-dicysteine (99mTc-EC). In addition, a kidney efficiency index (KEi) was also worked out as a new parameter obtained by dividing the uptake constant K by the surface of the ROI of a given kidney, which can be interpreted as the average "efficiency" of clearance of a kidney.

MATERIAL AND METHODS

K and KEi values were verified in 72 studies selected retrospectively from patients referred routinely for DRS, with available current level of blood creatinine, used for calculation of estimated GFR (eGFR) according to a CKD-EPI formula. After splitting of eGFR values into individual kidneys according to SF, single kidney eGFR values (SKeGFR) were obtained and then used as a verification method for SF, K and KEi values.

RESULTS

Correlation between SF and SKeGFR values, rsp = 0.64, was significantly weaker (p < 0.0022) than the correlation of SKeGFR values with K uptake constants and KEi indices: 0.90 and 0.84, respectively.

CONCLUSIONS

Uptake constant K and KEi, as quantitative parameters, give the opportunity to analyze a function of each kidney separately and in an absolute way. KEi also allows for a reliable assessment of kidneys of atypical sizes (larger or smaller than average). It also gives the opportunity to create normative values for this parameter and may be useful in a number of clinical situations where the diagnostic effectiveness of such a relative parameter as SF, is severely limited, e.g. in assessing a large kidney with hydronephrosis or while differing a cirrhotic from hypoplastic (i.e. a small but properly functioning) kidney.

[Ureterocele associated with simplex ureter in children: clinical and therapeutic features]

L´urétérocèle est une dilatation pseudo-kystique de l´uretère terminal sous muqueux. C´est une uropathie malformative rare surtout si elle survient sur un uretère simplex. Il s´agit d´une étude rétrospective menée sur dix ans, de 12 dossiers de malades colligés au Service de Chirurgie Pédiatrique de l´Hôpital Fattouma Bourguiba de Monastir entre 2006 et 2016. L´âge moyen de nos malades est de 2,7 ans avec des limites allant de 7 jours à 11 ans, le sex-ratio est de 1. Le tableau clinique a été dominé par la fièvre en rapport avec une infection urinaire haute. Le diagnostic a été posé essentiellement par l´échographie rénale et vésicale, l´urographie intraveineuse (UIV) et l´uréthro-cystographie rétrograde (UCR). L´urétérocèle était unilatéral dans 10 cas et bilatérale dans 2 cas soit un total de 14 cas d´urétérocèles. Tous ont été sur uretère simplex et ont été opérées par voie endoscopique. Aucun incident peropératoire n´a été noté. Les suites opératoires étaient simples. Une amélioration clinique et radiologique a été obtenue dans tous les cas. L´urétérocèle sur uretère simplex est une malformation urinaire très rare. Non diagnostiquée à temps, elle peut retentir sur le haut appareil. Le traitement endoscopique est une alternative séduisante avec des résultats satisfaisants.

Assessment of Renal Function Based on Dynamic Scintigraphy Parameters in the Diagnosis of Obstructive Uro/Nephropathy

This study evaluates the usefulness of parameters allowing assessment of renal function in absolute values in dynamic renal scintigraphy (DRS) with 99mTc-ethylenedicysteine (99mTc-EC) uptake constant (K), mean transit time (MTT), and parenchymal transit time (PTT) in the diagnosis of obstructive uro/nephropathy. The study included 226 people: 20 healthy volunteers, for whom normative values of assessed parameters were determined, and 206 patients. Reproducibility of results obtained by two independent operators, specificity, correlation with estimated GFR (eGFR), and Cohen's kappa were used to evaluate reliability of assessed parameters. Normative values were as follows: K ≥ 1.6, MTT ≤ 250 s, and PTT ≤ 225 s. Reproducibility of determination of K (rs = 0.99) and MTT (rs = 0.98) was significantly higher than that of PTT (rs = 0.95) (p = 0.001). Specificity was 100% for K, 81% for MTT, and 91% for PTT. Correlation of eGFR with K (rs = 0.89) was significantly higher than with PTT (rs = 0.53) and with split function (SF) (rs = 0.66) (p < 0.0001). Cohen's kappa was κ = 0.89 for K, κ = 0.88 for MTT, and κ = 0.77 for PTT. In a group of patients where standard DRS parameters are unreliable (bilateral obstructive uro/nephropathy or single functioning kidney), the use of K (the most effective among assessed parameters) changed the classification of 23/79 kidneys (29%). K enables reproducible assessment of absolute, individual kidney function without modifying routine DRS protocol. Diagnostic value of MTT and PTT is limited.

Ureteral Obstruction Due to Radiolucent Atazanavir Ureteral Stones

Background: Protease inhibitors (PIs) are a well-documented cause of nephrolithiasis. Although medications such as indinavir are known to increase risk of stone formation, the association of newer HIV medications is not as well studied. In this study, we report a case of a patient who developed atazanavir stones.

Case Presentation: A 74-year-old man with HIV on antiretroviral therapy—including atazanavir, a PI—presented with right flank pain. He previously had passed two ureteral stones that were not analyzed. A CT scan showed mild right hydronephrosis without evidence of nephrolithiasis or ureteral obstruction. The patient was presumed to have passed a stone and was discharged home. He returned one day later with persistent flank pain and acute kidney injury that did not improve with intravenous fluid hydration. A right ureteral stent was placed that relieved his symptoms. Subsequent ureteroscopy demonstrated bilateral ureteral stones that were basket extracted. Stone composition was 100% atazanavir. Since being switched off of this medication, the patient has not had any further episodes of renal colic and his renal function has improved to below his baseline level on presentation.

Conclusion: Patients treated with the PI atazanavir are at risk for developing nephrolithiasis and obstructive uropathy. Because these stones can be radiolucent on CT scan, a high level of suspicion is required to accurately diagnose ureteral obstruction in these patients. Alternative effective HIV treatment regimens can to be utilized when clinically indicated.

[Post infectious urethral stenosis and megacalycosis: a train that hides another]

La mégacalicose est une uropathie malformative rare caractérisée par une dilatation non obstructive des calices avec hypoplasie de la médullaire rénale. Nous rapportons un cas de mégacalicose associée à une sténose urétérale bilatérale d'origine infectieuse.

Verification of relationships between anthropometric variables among ureteral stents recipients and ureteric lengths: a challenge for Vitruvian-da Vinci theory

Objective

To determine and verify how anthropometric variables correlate to ureteric lengths and how well statistical models approximate the actual ureteric lengths.

Materials and methods

In this work, 129 charts of endourological patients (71 females and 58 males) were studied retrospectively. Data were gathered from various research centers from North and South America. Continuous data were studied using descriptive statistics. Anthropometric variables (age, body surface area, body weight, obesity, and stature) were utilized as predictors of ureteric lengths. Linear regressions and correlations were used for studying relationships between the predictors and the outcome variables (ureteric lengths); P-value was set at 0.05. To assess how well statistical models were capable of predicting the actual ureteric lengths, percentages (or ratios of matched to mismatched results) were employed.

Results

The results of the study show that anthropometric variables do not correlate well to ureteric lengths. Statistical models can partially estimate ureteric lengths. Out of the five anthropometric variables studied, three of them: body frame, stature, and weight, each with a P<0.0001, were significant. Two of the variables: age (R²=0.01; P=0.20) and obesity (R²=0.03; P=0.06), were found to be poor estimators of ureteric lengths. None of the predictors reached the expected (match:above:below) ratio of 1:0:0 to qualify as reliable predictors of ureteric lengths.

Conclusion

There is not sufficient evidence to conclude that anthropometric variables can reliably predict ureteric lengths. These variables appear to lack adequate specificity as they failed to reach the expected (match:above:below) ratio of 1:0:0. Consequently, selections of ureteral stents continue to remain a challenge. However, height (R²=0.68) with the (match:above:below) ratio of 3:3:4 appears suited for use as estimator, but on the basis of decision rule. Additional research is recommended for stent improvements and ureteric length determinations.

Endometriosis of the bladder as a cause of obstructive uropathy

A 47-year-old woman (gravida 1, para 1) with menorrhagia and pelvic pain was found to have an enlarged fibroid uterus and bladder mass on ultrasonographic imaging. The patient underwent an abdominal supracervical hysterectomy and transurethral bladder mass resection. Histopathologic findings revealed leiomyoma uteri, intramural adenomyosis, and bladder endometriosis. Most case series of bladder endometriosis include women that present with urinary symptoms. This is a rare case of obstructive uropathy secondary to bladder endometriosis in a patient without any urinary signs or symptoms.

Surgical management of vesicoureteral reflux in children

Vesicoureteral reflux (VUR) is the most common uropathy affecting children. Compared to children without VUR, those with VUR have a higher rate of pyelonephritis and renal scarring following urinary tract infection (UTI). Options for treatment include observation with or without antibiotic prophylaxis and surgical repair. Surgical intervention may be necessary in patients with persistent reflux, renal scarring, and recurrent or breakthrough febrile UTI. Both open and endoscopic approaches to reflux correction are successful and reduce the occurrence of febrile UTI. Estimated success rates of open and endoscopic reflux correction are 98.1% (95% CI 95.1, 99.1) and 83.0% (95% CI 69.1, 91.4), respectively. Factors that affect the success of endoscopic injection include pre-operative reflux grade and presence of functional or anatomic bladder abnormalities including voiding dysfunction and duplicated collecting systems. Few studies have evaluated the long-term outcomes of endoscopic injection, and with variable results. In patients treated endoscopically, recurrent febrile UTI occurred in 0-21%, new renal damage in 9-12%, and recurrent reflux in 17-47.6% of treated ureters with at least 1 year follow-up. These studies highlight the need for standardized outcome reporting and longer follow-up after endoscopic treatment.

Endoscopic management is the preferred "treatment" modality for grade III vesicoureteric reflux with breakthrough infections in a young girl

Endoscopic subureteric injection of tissue-augmenting substances has become an alternative to long-term antibiotic prophylaxis and open surgery, in the treatment of children with vesicoureteric reflux (VUR). Successful elimination of reflux in about 80% of patients after a single injection (and in 90% after a repeat) has been achieved using non-degradable substances. young girl with grade III VUR and breakthrough infections would definitely need to undergo antireflux procedure. Endoscopic treatment would be an ideal procedure as it is a one-day surgery, with over 80% success rate, low morbidity and no long-term complications. Moreover, this form of surgery is appealing to, as well as the choice of the majority of parents.

Vesicoureteral reflux: surgical and endoscopic treatment

The optimal management of vesicoureteral reflux (VUR) is quite controversial. For many years, only antibiotic prophylaxis and open surgery were considered possible options. Since the first descriptions in the early 1980s, endoscopic treatment (ET) has gained popularity and is now considered a valid alternative both to open surgery and antibiotic prophylaxis. Many surgical antireflux techniques have been described in the past 50 years. The general principle of reflux surgery, usually defined as ureteric reimplantation, is elongation of the submucosal ureteral tunnel with creation of a flap-valve mechanism. The antireflux operation can also be carried out laparoscopically, either extravesically or intravesically (pneumovesicum). Open surgery is associated with a high success rate (>95%) regardless of the technique adopted. However, because it is invasive, it is limited to selected cases. Laparoscopic technique is less invasive, but the mean operative time is much longer and results depend significantly on the learning curve. ET involves injecting material endoscopically into the submucosal space under the ureteric orifice. It is associated with a good success rate (about 80% after one injection). Advantages of this minimally invasive treatment include repeatability and the fact that postoperative complications are rare. With a second injection, after few months if needed, the success rate of ET approaches that of open surgery. Our 20-year experience in ET is described in detail in this paper, as this technique has changed the management algorithm for VUR dramatically.