Imaging in upper urinary tract infections

Unilateral renal cortical necrosis

A 51-year-old woman presented to her local emergency department with acute onset right-sided flank pain and nausea. Her blood results on admission were largely unremarkable aside from leucocytosis and neutrophilia. Two days after admission, she developed the following: stage 3 AKI with oliguria, anaemia, thrombocytopenia, and acute derangement of liver function tests. A computed tomography of the kidney ureter bladder demonstrated a right-sided 4 mm obstructing vesicoureteric junction stone with associated hydronephrosis and hydroureter. She was transferred to a tertiary care centre; gram negative sepsis was confirmed with a Proteus on blood culture and laboratory findings were in keeping with DIC. She was treated with Tazobactam/Piperacillin and intravenous fluids. In addition, further imaging showed improving right-sided hydronephrosis and left renal cortical necrosis. The aetiology of this presentation was sepsis complicated by disseminated intravascular coagulation. The coagulopathy likely contributed to the unilateral renal cortical necrosis. Cortical necrosis usually affects both kidneys, and is typically a complication of sepsis, shock, or obstetrical trauma. To our knowledge, there are only 2 reported cases of unilateral renal cortical necrosis and contralateral hydronephrosis with renal colic and septic shock. Potential pathogenetic mechanisms are discussed.

Outcome of febrile neutropenic patients treated for bacteriuria in hematology

INTRODUCTION

Positive urine sample is a frequent finding in post-chemotherapy febrile neutropenia (FN) and can lead to prolonged antibiotic therapy. The aim of this study was to assess the outcome of bacteriuria episodes in FN patients receiving targeted antibiotic therapy.

MATERIALS AND METHODS

A multi-centric retrospective study was conducted over a four-year period (2014-2019) on systematic urinalysis. All consecutive first bacteriuria episodes (≤ 2 bacteria with at least ≥ 10³ CFU/mL) during FN in hospitalized adult patients for hematological malignancies were included. Relapse and recurrence were defined by fever or urinary tract symptoms (UTS) with the same bacterial subspecies in urine occurring ≤ 7 days and ≤ 30 days, respectively, after antibiotic discontinuation. Mortality rate was determined at 30 days. Targeted antibiotic therapy ≤ 10 days for women and ≤ 14 for men was considered as short course.

RESULTS

Among 97 patients, 105 bacteriuria episodes on systematic urinalysis were analyzed; 67.6% occurred in women, 41.9% in AML patients, 17.1% were bacteremic, 14.2% presented with UTS, and 61.9% were treated with short-course antibiotic treatment. One death was reported. In men, no relapse/recurrence was noted, even in the short-course antibiotic group. In women, 2.8% of episodes treated with short-course antibiotic led to relapse or recurrence.

CONCLUSIONS

Relapse, recurrence, and mortality were uncommon events in FN patients experiencing bacteriuria episode, whatever the antibiotic duration. To distinguish asymptomatic bacteriuria from infection remained challenging in women. In men, systematic urinalysis at onset of FN could be useful.

Clinical investigation on acute pyelonephritis without pyuria

Background

The current guidelines for the diagnosis of acute pyelonephritis (APN) recommend that APN be diagnosed based on the clinical features and the presence of pyuria. However, we observed that some of the patients who are diagnosed with APN do not have characteristic clinical features or pyuria at the initial examination. We performed this study to investigate the characteristics of APN without pyuria.

Methods

A retrospective, cross-sectional study was conducted on 391 patients diagnosed with APN based on clinical and radiologic findings, between 2015 and 2019. The clinical features, laboratory results, and computed tomography (CT) findings were compared between patients with normal white blood cell (WBC) counts and those with abnormal WBC counts (WBC of 0-5/high power field [HPF] vs. >5/HPF) in urine.

Results

More than 50% of patients with APN had no typical urinary tract symptoms and one-third of them had no costovertebral angle (CVA) tenderness. Eighty-eight patients (22.5%) had normal WBC counts (0-5/HPF) on urine microscopy. There was a negative correlation between pyuria (WBC of >5/HPF) and previous antibiotic use (odds ratio, 0.249; 95% confidence interval, 0.140-0.441; p<0.001), and the probability of pyuria was reduced by 75.1% in patients who took antibiotics before visiting the emergency room.

Conclusion

The diagnosis of APN should not be overlooked even if there are no typical clinical features, or urine microscopic examination is normal. If a patient has already taken antibiotics at the time of diagnosis, imaging studies such as CT should be performed more actively, regardless of the urinalysis results.

Complicated urinary tract infection in patients with benign prostatic hyperplasia

Complicated urinary tract infection (UTI) is a symptomatic urinary infection accompanied by functional or structural abnormalities of the genitourinary tract. Benign prostatic hyperplasia (BPH) is a major cause of lower urinary tract obstruction in male patients, and bladder outlet obstruction (BOO) secondary to BPH can lead to UTIs in men. However, no evidence has clearly shown that UTI in the aging male population is associated with either post-void residual urine or BOO. Screening for the presence of bacteriuria is recommended prior to any procedure manipulating the urinary tract, and imaging studies of the upper urinary tract are recommended to identify underlying abnormalities. Recurrent or persistent UTI in men with BPH is an indication for surgical treatment. Asymptomatic bacteriuria should be screened for and treated before transurethral resection of the prostate (TURP). In addition, antibiotic prophylaxis reduced the risk of UTI in patients undergoing TURP. The choice of specific antimicrobial for prophylaxis should be based on local pathogen prevalence and individual antibiotic susceptibility. Patients with severe systemic infections require hospitalization, and empirical therapy should include an intravenous antimicrobial regimen. Further prospective studies are needed to refine the treatment process for complicated UTI in patients diagnosed with BPH.

Intermittent quick-check CT fluoroscopy-guided percutaneous drainage placement in patients with infected renal and perirenal fluid collections: 11-year experience

PURPOSE

We aimed to evaluate technical and clinical success and safety of computed tomography fluoroscopy (CTF)-guided percutaneous pigtail drainage (PPD) placement in patients with infected renal and perirenal fluid collections.

METHODS

This retrospective analysis comprised 44 patients (52.27% men; age, 57.1±18.5 years) undergoing low-milliampere (10-20 mA) CTF-guided PPD placement in 61 sessions under local anesthesia from August 2005 to November 2016. Infected fluid collections (n=71) included infected renal cysts (12.68%), renal and perirenal abscesses due to comorbidities (23.94%), or fluid collections after renal surgery or urological intervention (63.38%). Technical success was defined as PPD placement with consecutive fluid aspiration, clinical success as normalization or marked improvement of clinical symptoms (e.g., flank pain, fever) and inflammatory parameters (leukocyte count, C-reactive protein) after minimally invasive combination therapy (intravenous broad-spectrum antibiotics and drainage). Complications were classified according to the CIRSE classification.

RESULTS

Overall, 73 single lumen PPD (7.5-12 F) were utilized (1 PPD per session, 69.86%; 2 PPD per session, 15.07%). In 4 cases, PPD could not be inserted into the fluid collection (4.11%) or could not be aspirated (1.37%), yielding overall 94.5% primary technical success. Mean duration of functioning PPD before removal was 10.9 days. Adverse events within 30 days comprised PPD failure (2.27%) or secondary dislocation (Grade 3, 11.36%) and one death (Grade 6, unrelated to intervention, 2.27%). Additional invasive measures after primary CTF-guided PPD were required in 5 patients (nephrectomy 6.82%, partial nephrectomy 2.27%, surgical drainage 2.27%). Thus, clinical success using only minimally invasive measures was achieved in 39 of 44 patients (88.64%).

CONCLUSION

Given a minor proportion of patients requiring surgical revision, combined antibiotics and CTF-guided PPD of infected renal and perirenal fluid collections provides an excellent technical and clinical outcome.

Imaging of ureter: a primer for the emergency radiologist

In this review article, we will discuss the gamut of abnormalities involving the ureters. In the emergency department, ureterolithiasis is the most common indication for imaging abdomen and pelvis. However, spectrum of ureteral abnormalities including congenital, infectious and inflammatory, primary and secondary ureteral malignancies, retroperitoneal fibrosis rare described in this article may be encountered. Thus, we will describe acute subacute as well as chronic conditions that may affect ureter. Knowledge of common, as well as rare entities and their imaging features, is of utmost importance to enable appropriate management.

CT and MRI in Urinary Tract Infections: A Spectrum of Different Imaging Findings

There are many acute and chronic infections affecting the urinary tract including bacterial, fungal and viral infections. Urinary tract infections (UTIs) can present in many different patterns with variable degrees of severity varying from asymptomatic and uncomplicated forms to life threatening complicated infections. Cross-sectional imaging techniques—including both computed tomography (CT) and magnetic resonance imaging (MRI)—have become very important tools not only for evaluation of UTIs, but also for detection of associated complications. Selection of either CT or MRI in the UTI evaluation depends on several factors such as the presence of contraindication, experience, cost and availability. CT and MRI help in early detection and management of UTIs that reduce the prevalence and severity of complications. In this article we will present the radiologic findings at CT and MRI in different types of upper and lower UTIs including acute pyelonephritis, intrarenal and perinephric abscesses, pyonephrosis, chronic pyelonephritis, emphysematous UTIs, xanthogranulomatous pyelonephritis, tuberculosis (TB), bilharziasis, fungal infection, corynebacterium infection, ureteritis, cystitis, prostatitis, prostatic abscess and urethritis.

Infectious and Inflammatory Diseases of the Urinary Tract: Role of MR Imaging

Urinary tract infection (UTI) is among the most common of bacterial infections. Imaging studies are only required in cases of complicated UTIs. Ultrasound remains the first-line imaging method; however, CT is the gold standard for evaluation of UTIs. MR imaging's improved contrast resolution and absence of ionizing radiation may recommend its use for assessment of lower UTIs. Furthermore, MR imaging performs with diagnostic accuracy at least similar to CT in complicated UTIs, except for the identification of calculi and emphysematous pyelonephritis. In this article, the role of MR imaging for the evaluation of infectious and inflammatory disease processes of the urinary tract is reviewed.

Imaging features of primary renal lymphoma

Background Cases of primary renal lymphoma (PRL) are quite rare and are often mistaken for renal cell carcinoma. Purpose To determine the multislice computed tomography (MSCT) and magnetic resonance imaging (MRI) characteristics of PRL. Materials and Methods Twenty-three patients with PRL were identified by CT and MRI, and their tumor characteristics were assessed. Results Tumors exhibited single or multifocal nodules (n = 19) and diffuse renal enlargement (n = 4). Twenty-two tumors exhibited an infiltrative appearance. There was no evidence of calcification in any of the cases. Twenty-one tumors displaced or wrapped around abdominal vessels rather than encasing them. Enlarged retroperitoneal nodes were observed in three cases. Neither extension into the venous system nor distant metastasis was found. Tumor enhancement was of low attenuation compared with that of normal renal cortex and medulla ( P < 0.05). PRL was isointense on T1-weighted imaging, slightly hypointense on T2-weighted imaging and hyperintense on diffusion-weighted imaging. Twenty-two patients exhibited biopsy-confirmed PRN. There were four, 12, and seven cases of low-grade, intermediate-grade, and high-grade tumors, respectively. Patient were followed up over 16 to 166 months. Six patients died within three years and five patients died within five years. Conclusion Infiltrative appearance and tumor displacement or extension around abdominal vessels rather than vessel encasement are common findings on CT or MRI imaging and may suggest a diagnosis of PRL.

Integrated Pathophysiology of Pyelonephritis

Pyelonephritis represents a subset of urinary tract infections that occur from bacteria ascending from the lower to the upper reaches of the genitourinary system, such as the kidney. The renal system contains a range of hydrodynamically and immunologically challenging, interconnected microenvironments where the invading pathogen may populate during the course of the infection. The situation at the infection foci changes dynamically, vacillating between bacterial colonization and clearance, to which the outcome is a summation of all host-pathogen elements in play. A selection of important determinants includes factors of microbial origin, effects of eukaryotic cell signaling, physiological facets of the infected organ, and signals from distal organs. Improved understanding of the multifactorial aspects of molecular pathogenesis of infection requires intravital, cross-disciplinary approaches with high spatio-temporal resolution. The advancement of such approaches promises to eventually provide a comprehensive understanding of the integrated pathophysiology of pyelonephritis.

Acute Urinary Tract Disorders

Acute urinary tract disorders often manifest as flank pain and are a common complaint of patients who present to the emergency department. The pain is often a vague, poorly localized sensation that may have a variety of causes. Laboratory and clinical findings, such as hematuria, are neither sensitive nor specific for determining the cause of the flank pain. Accordingly, imaging is an important tool in determining a diagnosis and management plan. Patients with acute urinary tract disorders who present with pain include those with calculi as well as renal infection, vascular disorders, and hemorrhage.

Long-Term Results after Acute Therapy of Obstructive Pyelonephritis

Introduction: To evaluate therapeutic results till 5 years after therapy of obstructive pyelonephritis (OPN) emphasizing regular follow-up. Material and Methods: During 5 years, 57 patients with OPN were treated. The patients' charts were reviewed retrospectively for clinical data. These were completed by a questionnaire. Results: In the group of 57 patients (average age 56 years), about two third were women. Urolithiasis (65%) and tumors (21%) were the main causes of obstruction; fever (91%) and loin pain (86%) the main symptoms. Three fourth of the patients showed renal insufficiency and nearly 50% anemia. E. coli and Proteus spp. were the dominating organisms. Sonography detected obstruction in 93% cases. In one third of cases, CT scan was added; 81% percutaneous nephrostomy and 19% ureteral stenting were the initial methods of urinary drainage. During therapy, 23% nephrectomies (19% complete, 4% partial) were performed. Long-term follow-up showed 11% recurrent OPN and 33% recurrent UTI. Conclusions: After diagnosis of OPN, primary nephrostomy or ureteral stenting and antibiotic therapy are the first measures. If recurrent urinary tract infections or OPN occur, long-term follow-up and low-dose antibiotic prophylaxis may be discussed.

Is the mean platelet volume a predictive marker for the diagnosis of acute pyelonephritis in children?

BACKGROUND

Acute pyelonephritis (APN) can lead to renal scar formation, high blood pressure, and end-stage renal failure. Prompt and early diagnosis of APN is important for preventing future complications. Our goal was to study the mean platelet volume (MPV) as a predictor of APN in children.

METHODS

The records of 43 patients with APN and 51 patients with a lower urinary tract infection (UTI) were investigated prospectively. APN was confirmed using radioactive nuclide 99mTc-DMSA scanning. The white blood cell (WBC) count, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and MPV of both groups were measured and compared.

RESULTS

The WBC count, MPV and ESR values, and the serum concentration of CRP were higher in the APN group than in the lower UTI group (p < 0.05). In the children with APN, the optimal cut-off value for the MPV was 8.2 fl [area under the curve (AUC): 0.906], with sensitivity of 81.4 % and specificity of 86.3 %. The MPV was associated with APN (p = 0.001), and the sensitivity and specificity of the MPV for the diagnosis of APN were higher than those of the other inflammation markers. MPV > 8.2 fl yielded an adjusted OR of 7.8 (95 % CI 3.3-18.4, p < 0.001) for APN. MPV > 8.2 fl was significantly associated with late renal scar formation (adjusted OR 5.7, 95 % CI 2.3-13.8, p < 0.001).

CONCLUSION

The MPV is a fast and reliable measurement with considerable predictive value for the diagnosis of APN and renal scars, and its predictive capacity is better than that of CRP, ESR, and WBC values.

Radiological findings of sexual intercourse related emergency department admissions: a first overview

Objectives

Sexuality is an essential aspect of human function, well-being and quality of life. Many people have sex without complications. However, there are some people who need to seek emergency medical help for related health problems. The aim of this study was to present a first overview of patients who received a radiological examination related to sexual intercourse based emergency department admission.

Methods

Our centralized electronic patient record database was reviewed for patients who had been admitted to our emergency department with an emergency after sexual intercourse between 2000 and 2011. The database was scanned for the standardized key words ‘sexual intercourse’ or ‘coitus’ retrospectively. For all patients identified in the electronic patient record database the radiological examinations were searched for manually in our Radiology Information System, and reviewed by three independent radiologists.

Results

One hundred and twenty nine out of 445 (29,0%) patients received a radiological examination after immediate emergency department admission related to sexual intercourse. Fifty two out of 129 (40.3%) patients had positive radiological findings while 77 (59.7%) did not. Eighty point seven percent (n = 42) of the radiological findings were a sexual intercourse-associated pathology and 19.2% (n = 10) were considered to be incidental findings. Age and male sex positively correlated with radiological imaging workup (p<0.001, respectively p<0.037). The most common sexual intercourse-associated pathology was headache attributed to cerebrovascular insult (n = 21, 40.3%) followed by epididymitis (n = 7, 16.6%) and obstructive uropathy (n = 5, 11.6%). Of the patients with headache attributed to non-traumatic intracranial hemorrhage, subarachnoid hemorrhage (n = 14, 66.6%) was the most common, followed by intracerebral bleeding (n = 4, 19.0%) and one subdural hemorrhage.

Conclusions

Pathological findings are manifold. Cerebral imaging is the most common type of radiological imaging performed. Further prospective and standardized studies should be performed to better evaluate the significance of radiological imaging in this patient collective with the aim to gain better knowledge on what patients profit from what type of radiological imaging when presenting with a sexual intercourse related emergency.

Advances in Knowledge

The present study provides a first overview on radiological findings of sexual intercourse related emergency department admissions.

Are serum procalcitonin and interleukin-1 beta suitable markers for diagnosis of acute pyelonephritis in children?

Rapid diagnosis of acute pyelonephritis is important because of its association with long-standing complications. This study was conducted to compare the reliability of serum procalcitonin (PCT) and interleukin-1 beta (IL-1β) with conventional laboratory parameters for diagnosis of acute pyelonephritis in children. Seventy nine children with urinary tract infection were divided into two groups based on the result of Tc-99m dimercaptosuccinic acid renal scan: acute pyelonephritis (n=33) and lower UTI (urinary tract infection) (n=46) groups. White blood cell (WBC) count, neutrophil count, erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), PCT and IL-1β concentrations of both groups were measured and compared. WBC count, neutrophil count, ESR, serum CRP, PCT and IL-1β concentrations were higher in acute pyelonephritis patients than in the lower UTI group (P<0.05). The sensitivity and specificity of serum PCT and IL-1β for diagnosis of acute pyelonephritis were 31, 84.7% and 27.2, 90% respectively (using a cut-point value of 0.5 ng/ml for PCT and 6.9 pg/ml for IL-1β). The sensitivity of PCT and IL-1β for diagnosis of acute pyelonephritis was less than that of conventional markers such as ESR and CRP. This study revealed that serum PCT and IL-1β are not good biologic markers for differentiating acute pyelonephritis from lower UTI. It seems that conventional inflammatory markers such as ESR and CRP besides the clinical findings are more reliable for the diagnosis of acute pyelonephritis in children.

Correlation between computerized tomography density measurements of urinary bladder and urinalysis results

Our aim was to investigate whether there is a correlation between computerized tomography (CT) density measurements of the urinary bladder and urinalysis results. Patients were subdivided into three groups with respect to urinalysis results: Group 1, no leukocytes or erythrocytes detected in urine (n=25); Group 2, erythrocytes detected in urine (n=50); and Group 3, leukocytes and erythrocytes detected in urine (n=98). In CT sections, densitometric measurements had been performed from three zones on each section and groups were compared in terms of densitometry results. Our results indicate that density measurements of CT views form the urinary bladder may provide valuable data on hematuria and leukocyturia.

Serum levels of interleukin-6 and interleukin-8 as diagnostic markers of acute pyelonephritis in children

Purpose

Early diagnosis and treatment of acute pyelonephritis in children is of special importance in order to prevent serious complications. This study was conducted to determine the diagnostic value of serum interleukin (IL)-6 and IL-8 in children with acute pyelonephritis.

Methods

Eighty-seven patients between 1 month to 12 years old with urinary tract infection (UTI) were divided into 2 groups based on the result of 99m-technetium dimercapto-succinic acid renal scan: acute pyelonephritis (n=37) and lower UTI (n=50) groups. White blood cell (WBC) count, neutrophil (Neutl) count, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP) concentration, platelet count, and serum IL-6 and IL-8 concentrations of both groups were measured and compared.

Results

There was a significant difference between two groups regarding WBC count, Neutl count, ESR, and CRP concentration (P<0.05). In addition, the difference between the two groups regarding serum IL-6 and IL-8 concentrations was not significant (IL-6, 60 and 35.4 pg/mL and IL-8, 404 and 617 pg/mL, respectively). The sensitivity and specificity of serum IL-6 and IL-8 for diagnosis of acute pyelonephritis were 73%, 42% and 78%, 32%, respectively. Sensitivity, specificity, negative and positive predictive values of serum IL-6 and IL-8 were less than those of acute phase serum reactants such as CRP.

Conclusion

This study showed that there was no significant difference between acute pyelonephritis and lower UTI groups regarding serum IL-6 and IL-8 levels. Therefore, despite confirming results of previous studies, it seems that IL-6 and IL-8 are not suitable markers for differentiating between acute pyelonephritis and lower UTI.