Current clinical management of renal and perinephric abscesses: a literature review

Guidelines for the Prevention, Diagnosis, and Management of Urinary Tract Infections in Pediatrics and Adults: A WikiGuidelines Group Consensus Statement

Importance

Traditional approaches to practice guidelines frequently result in dissociation between strength of recommendation and quality of evidence.

Objective

To create a clinical guideline for the diagnosis and management of urinary tract infections that addresses the gap between the evidence and recommendation strength.

Evidence Review

This consensus statement and systematic review applied an approach previously established by the WikiGuidelines Group to construct collaborative clinical guidelines. In May 2023, new and existing members were solicited for questions on urinary tract infection prevention, diagnosis, and management. For each topic, literature searches were conducted up until early 2024 in any language. Evidence was reported according to the WikiGuidelines charter: clear recommendations were established only when reproducible, prospective, controlled studies provided hypothesis-confirming evidence. In the absence of such data, clinical reviews were developed discussing the available literature and associated risks and benefits of various approaches.

Findings

A total of 54 members representing 12 countries reviewed 914 articles and submitted information relevant to 5 sections: prophylaxis and prevention (7 questions), diagnosis and diagnostic stewardship (7 questions), empirical treatment (3 questions), definitive treatment and antimicrobial stewardship (10 questions), and special populations and genitourinary syndromes (10 questions). Of 37 unique questions, a clear recommendation could be provided for 6 questions. In 3 of the remaining questions, a clear recommendation could only be provided for certain aspects of the question. Clinical reviews were generated for the remaining questions and aspects of questions not meeting criteria for a clear recommendation.

Conclusions and Relevance

In this consensus statement that applied the WikiGuidelines method for clinical guideline development, the majority of topics relating to prevention, diagnosis, and treatment of urinary tract infections lack high-quality prospective data and clear recommendations could not be made. Randomized clinical trials are underway to address some of these gaps; however further research is of utmost importance to inform true evidence-based, rather than eminence-based practice.

Gas-forming renal abscesses in critically ill patients: ultrasound-guided drainage

PURPOSE

This study aimed to describe and evaluate a real-time ultrasound-guided (US-guided) drainage technique for effective and safe drainage of gas-forming renal abscesses (GRA) in an intensive care unit(ICU).

MATERIALS AND METHODS

This retrospective study included four patients with GRA who were admitted to the ICU of a tertiary care center between September 2021 and September 2023. The patients were all comorbid with severe systemic infections and required drainage of abscesses for infection control. This study describes in detail the process of rapid and precise US-guided drainage of GRA by an ultrasound interventionist through certain maneuvers and techniques.

RESULTS

Six US-guided drainage procedures were completed in four patients, and seven catheters were placed accurately in the abscesses with a 100% success rate. No intraoperative or postoperative complications such as bleeding and peripheral organ damage were observed, and the median time with catheters was 13 days (8-46 days).

CONCLUSION

The technique of real-time US-guided drainage of GRA can be performed safely in the ICU without the need to leave the ICU, greatly reducing risk.

A Rare Case and Literature Review of Pyelo-Hepatic Abscess in an Immunocompetent Patient: When Effective Source Control and Targeted Antimicrobial Therapy Might Not Be Enough

Pyelo-hepatic abscess is a rare complication of upper urinary tract infections (UTIs). We describe a case of polymicrobial pyelo-hepatic abscess in an immunocompetent patient. A 71-year-old male patient with a double-J stent for right ureteral lithiasis was admitted in our Infectious Diseases Department for a pyelo-hepatic abscess. Despite a targeted antibiotic therapy against an extended spectrum betalactamase-negative Escherichia coli, the patient did not improve. Further examinations revealed a possible polymicrobial aetiology, including Candida spp. and E. coli resistant to piperacillin/tazobactam but sensitive to third-generation cephalosporins. To date, a paucity of articles regarding pyelo-hepatic abscess exist, consisting mostly of case reports. Urinary stones and a ureteral stent indwelling time exceeding 90 days are known risk factors for upper UTIs and for bacterial dissemination in contiguous organs. Pyelo-hepatic abscesses usually involve Gram-negative bacilli, but they can be polymicrobial, including fungi. As a range of factors could limit the efficacy of antibiotics inside an encapsulated lesion and might contribute to the selection of resistant species during treatment, clinicians should be aware of this complication and try to prevent this event by acting on the main modifiable risk factor.

Renal abscess complicating acute pyelonephritis in children: Two cases report and literature review

RATIONALE

To describe the diagnostic and treatment approaches of renal abscesses complicated with acute pyelonephritis in children.

PATIENT CONCERNS

Two children presented with fever, vomiting, and abdominal pain with no typical manifestations, like frequent urination, urgency, dysuria, hematuria, foam urine, and lumbago. Renal abscess complicating acute pyelonephritis was diagnosed by B-ultrasound and computed tomography enhancement. Moreover, inflammatory markers were elevated significantly, but routine blood and urine cultures were repeatedly negative. The empirical anti-infection therapy had no obvious effect. A pathogenic diagnosis was confirmed in case two, and macro gene detection in blood and urine guided the follow-up treatment.

DIAGNOSES

Both children were diagnosed with acute gastroenteritis on admission, but renal abscess complicating acute pyelonephritis were diagnosed by imaging examination.

INTERVENTIONS

Both children were given anti-infection therapy of third-generation cephalosporin, which had no obvious effect. Routine blood and urine cultures were repeatedly negative. Case one was changed to piperacillin sodium tazobactam. We further carried out blood and urinary metagenomic next-generation sequencing detection for case two. Meanwhile, meropenem and linezolid anti-infection treatment was given. The results showed overlapping infection with Escherichia coli and Enterococcus faecalis. According to the genetic test results, amoxicillin clavulanate potassium combined with nitrofurantoin were prescribed after discharge.

OUTCOMES

Clinical symptoms of the 2 children disappeared, the infection was controlled, and imaging showed that renal abscess complicated with acute pyelonephritis disappeared.

LESSONS

The clinical spectrum of renal abscess complicating acute pyelonephritis is vague, with no specific manifestations, and can be easily misdiagnosed. B-ultrasound and computed tomography enhancement are helpful in making a definite diagnosis. Moreover, the sensitivity of routine culture is low, and metagenomic next-generation sequencing might be helpful to detect pathogenic microorganisms and guided treatment. Early treatment with broad-spectrum antibiotics might have favorable outcomes.

A pictorial review of genitourinary infections and inflammations

Various infectious and inflammatory diseases affect the genitourinary system. This paper provides a review of multiple common and uncommon infectious and inflammatory conditions affecting the genitourinary system and some associated complications. These include acute infectious cystitis, emphysematous cystitis, acute pyelonephritis, emphysematous pyelonephritis, renal and perinephric abscesses, pyonephrosis, xanthogranulomatous pyelonephritis, epididymo-orchitis, vasitis, prostatitis, pelvic inflammatory disease, renal hydatid infection, renal tuberculosis, actinomycosis, Erdheim-Chester Disease, IgG4-Related Kidney Disease, urethritis and urethral strictures, ureteritis cystica, and genitourinary fistulas. Radiologists should be aware of these diseases' complications and management. Uncommon conditions must be considered when evaluating the genitourinary system.

Endogenous endophthalmitis secondary to perirenal abscess

Introduction

Endogenous Endophthalmitis is a rare ocular infection but with poor visual prognosis for most patients. Its most frequent etiology is Klebsiella spp., associated with hepatic abscesses and less frequently with perirenal abscesses.

Case presentation

We present a 61-year-old woman with a history of poorly controlled diabetes mellitus 2 that consulted several times for acute pyelonephritis with torpid evolution, associated with endogenous endophthalmitis in her right eye that required evisceration.

Conclusion

Adequate management of acute pyelonephritis can avoid local or distant complications, such as endogenous endophthalmitis, an infection with poor visual prognosis that requires high clinical suspicion for timely management with better visual outcomes and lower morbimortality.

Adrenal Abscesses: A Systematic Review of the Literature

Objective: To summarize the existing knowledge about adrenal gland abscesses, including etiology, clinical presentation, common laboratory and imaging findings, management and overall morbidity and mortality. Design: Systematic literature review. Methods: We performed a search in the PubMed database using search terms: 'abscess and adrenal glands', 'adrenalitis', 'infection and adrenal gland', 'adrenal abscess', 'adrenal infection' and 'infectious adrenalitis'. Articles from 2017 to 2022 were included. We found total of 116 articles, and after applying exclusion criteria, data from 73 articles was included in the final statistical analysis. Results: Of 84 patients included in this review, 68 were male (81%), with a mean age of 55 years (range: 29 to 85 years). Weight loss was the most frequent symptom reported in 58.3% patients, followed by fever in 49%. Mean duration of symptoms was 4.5 months. The most common laboratory findings were low cortisol (51.9%), elevated ACTH (43.2%), hyponatremia (88.2%) and anemia (83.3%). Adrenal cultures were positive in 86.4% cases, with Histoplasma capsulatum (37.3%) being the leading causative agent. Blood cultures were positive in 30% of patients. The majority of the adrenal infections occurred through secondary dissemination from other infectious foci and abscesses were more commonly bilateral (70%). A total of 46.4% of patients developed long-term adrenal insufficiency requiring treatment. Abscess drainage was performed in 7 patients (8.3%) and adrenalectomy was performed in 18 (21.4%) patients. The survival rate was 92.9%. Multivariate analysis showed that the only independent risk factor for mortality was thrombocytopenia (p = 0.048). Conclusion: Our review shows that adrenal abscesses are usually caused by fungal pathogens, and among these, Histoplasma capsulatum is the most common. The adrenal glands are usually involved in a bilateral fashion and become infected through dissemination from other primary sources of infection. Long-term adrenal insufficiency develops in 46% of patients, which is more common than what is observed in non-infectious etiology of adrenal gland disorders. Mortality is about 7%, and the presence of thrombocytopenia is associated with worse prognosis. Further prospective studies are needed to better characterize optimal testing and treatment duration in patients with this relatively rare but challenging disorder.

A Rare Case of Bilateral Renal Abscess from Staphylococcal Infection in a Young Healthy Patient

Bilateral renal abscess is a rare infectious disease. Most patients have some risk factors for comorbidities, such as diabetes or an abnormal urinary tract, causing abscess formation. The incidence of the disease is infrequent in young healthy adults. Here, we report a case of a previously healthy non-diabetic young man who presented with abdominal pain with a high-grade fever. With clinically persistent abdominal pain, computerized tomography of the whole abdomen was done. The result showed bilateral renal abscess. The culture from the abscess reported Staphylococcus aureus. The patient's clinical abdominal pain and fever resolved after receiving antibiotics for 4 weeks.

A Renal Abscess Caused by Nontyphoid Salmonella in an Immunocompetent Adult

Renal abscesses are uncommon in adults and are typically caused by gram-negative bacteria such as Escherichia coli, Proteus mirabilis, or Staphylococcus aureus. Nontyphoid Salmonella abscesses are infrequent. We discuss the case of a 27-year-old previously healthy female who developed a renal abscess due to Salmonella enterica. Abdominal computed tomography (CT) revealed a left renal abscess (size 11.6 cm × 8.2 cm) and 1.9 cm cyst in the right kidney. The urine and abscess aspirate cultures indicated the presence of gram-negative bacilli and lactose-negative Salmonella. A presumptive diagnosis of the left renal abscess was made. A urologist was consulted, and the patient was prepared for a left-sided nephrectomy. The patient's condition improved following treatment with a combination of piperacillin/tazobactam and moxifloxacin. Based on our experience, prompt recognition of nontyphoidal Salmonella as a potential cause of a renal abscess is important to prevent complications such as the extension of the abscess and the spread of the pathogen to adjacent structures.

Percutaneous nephroscopy combined with ultrasound-guided negative-pressure suction for the treatment of perinephric abscess: a case series

Background

Drainage is indicated in many patients with a perinephric abscess (PA). Surgical drainage is associated with trauma and slow recovery, while percutaneous drainage can be ineffective in some patients. We report on 11 patients with PA treated by percutaneous nephroscopy combined with ultrasound-guided negative-pressure suction under local anesthesia.

Methods

This case series included 11 PA patients operated on from January 2013 to June 2020. All patients received percutaneous nephroscopy combined with ultrasound-guided negative-pressure suction. Data, including operation time, volume of intraoperative blood loss, volume of intraoperative pus suction, time of postoperative drainage tube indwelling, time to restore normal body temperature, length of postoperative hospital stay, and intraoperative and postoperative complications, were collected.

Results

The age of the patients was 59 (53–69) years. Eight, six, two, and two patients had hypertension, type 2 diabetes, rheumatoid arthritis, and renal calculi, respectively. The operations were successful forall11 patients. Eight, two, and one patients required one, two, and three channels, respectively, to clear their abscess. The average operation time was 44 (30–65) min, and intraoperative blood loss was 16 (10–20) ml. The volume of intraoperative pus suction was 280 (200–400) ml, time of postoperative drainage tube indwelling was 8.2 (6–12) days, and time to restoring normal body temperature was 0.8 (0.5–2) days. The average postoperative hospital stay was 9.8 (7–14) days. No severe intraoperative or postoperative complications occurred. The postoperative follow-up time was typically 4.8 (3–8) months, and there were no recurrences.

Conclusion

Percutaneous nephroscopy combined with ultrasound-guided negative-pressure suction might be a feasible method for treating PA.

Renal abscess in children: Is size an important determinant in deciding treatment options?

Background:

Renal abscess (RA) is rarely seen in the paediatric age group. The proposed management protocols are mainly derived from the adult series which may not be appropriate in children.

Objective:

In this retrospective analysis of cases with renal and perinephric abscesses, the objective is to correlate the clinical presentation, radiological findings and treatment options and also to propose a paediatric-specific practical management algorithm.

Study design:

This is a retrospective study of cases with renal and perinephric abscesses admitted between March 2012 and February 2020. The patients were reviewed for demographics, presentation, predisposing factors, laboratory investigations, imaging, management and outcome.

Results:

Analysis of 12 paediatric patients (13 renal units) with RA (median age 4 years) was done. Organisms were isolated in 8 of 12 (66.6%) patients with Gram-negative organisms being the commonest. On admission, all patients were started on empirical broad-spectrum antibiotics. Except for two patients who were critically ill with frank sepsis and had a tender renal lump, the rest of them were initially offered conservative management with intravenous antibiotics, and the response was reviewed after 48–72 hours. Of five units with abscess size of ⩽3 cm, two units (40%) responded to conservative management, while three units (60%) required intervention, and of eight units of size >3 cm, three units (37.5%) responded to conservative management and five units (62.5%) required intervention. None of the abscesses with perinephric collection (30.7%) responded to antibiotics and required intervention.

Conclusion:

A protocol based on the size of RA as recommended in most of the adult series may not be appropriate in the paediatric age group because of the differences in clinical presentation, predisposing factors and immune response. The clinical condition on presentation, response to antibiotic therapy and the presence of perinephric collection should be considered as an important determinant in deciding the need for intervention.

Level of evidence:

4

A case of a renal abscess caused by Salmonella bareilly in a previously healthy boy

Background

Renal abscesses are relatively uncommon in children, and usually due to Gram-negative rods or Staphylococcus aureus, whereas abscesses caused by Salmonella are very rare.

Case presentation

We present the case of a previously healthy 10-year-old boy who had a renal abscess due to Salmonella bareilly. He responded well to treatment with antibiotics, and computed tomography (CT)-guided drainage of the abscess. His blood, urine and abscess aspirate cultures were sterile, but a broad-range 16S rDNA polymerase chain reaction (PCR) assay of the aspirate followed by analysis of four Salmonella genes (fliC, fliD, sopE2, and spaO) identified S. bareilly as the causative agent.

Conclusion

To the best of our knowledge, this is the first report of renal abscess caused by S. bareilly.

Copper Resistance Promotes Fitness of Methicillin-Resistant Staphylococcus aureus during Urinary Tract Infection

Urinary tract infection (UTI) is one of the most common infectious conditions affecting people in the United States and around the world. Our knowledge of the host-pathogen interaction during UTI caused by Gram-positive bacterial uropathogens is limited compared to that for Gram-negative pathogens. Here, we investigated whether copper and the primary copper-containing protein, ceruloplasmin, are mobilized to urine during naturally occurring UTI caused by Gram-positive uropathogens in patients. Next, we probed the role of copper resistance in the fitness of methicillin-resistant Staphylococcus aureus (MRSA) during experimental UTI in a murine model. Our findings demonstrate that urinary copper and ceruloplasmin content are elevated during UTI caused by Enterococcus faecalis, S. aureus, S. epidermidis, and S. saprophyticus. MRSA strains successfully colonize the urinary tract of female CBA mice with selective induction of inflammation in the kidneys but not the bladder. MRSA mutants lacking CopL, a copper-binding cell surface lipoprotein, and the ACME genomic region containing copL, exhibit decreased fitness in the mouse urinary tract compared to parental strains. Copper sensitivity assays, cell-associated copper and iron content, and bioavailability of iron during copper stress demonstrate that homeostasis of copper and iron is interlinked in S. aureus. Importantly, relative fitness of the MRSA mutant lacking the ACME region is further decreased in mice that receive supplemental copper compared to the parental strain. In summary, copper is mobilized to the urinary tract during UTI caused by Gram-positive pathogens, and copper resistance is a fitness factor for MRSA during UTI. IMPORTANCE Urinary tract infection (UTI) is an extremely common infectious condition affecting people throughout the world. Increasing antibiotic resistance in pathogens causing UTI threatens our ability to continue to treat patients in the clinics. Better understanding of the host-pathogen interface is critical for development of novel interventional strategies. Here, we sought to elucidate the role of copper in host-Staphylococcus aureus interaction during UTI. Our results reveal that copper is mobilized to the urine as a host response in patients with UTI. Our findings from the murine model of UTI demonstrate that copper resistance is involved in the fitness of methicillin-resistant S. aureus (MRSA) during interaction with the host. We also establish a critical link between adaptation to copper stress and iron homeostasis in S. aureus.

Salmonella Renal Abscess in an Immunocompetent Child: Case Report and Literature Review

We describe a case of a 10-year-old immunocompetent girl with a left renal abscess due to Group C Salmonella (Salmonella serovar Oranienburg). Percutaneous drainage of the abscess was done. She also received 2 weeks of intravenous ceftriaxone, followed by 4 weeks of oral co-trimoxazole with resolution seen on ultrasound. A review of pediatric Salmonella renal abscesses is also presented.

Basic principles and new advances in kidney imaging

Over the past few years, clinical renal imaging has seen great advances, allowing assessments of kidney structure and morphology, perfusion, function and metabolism, and oxygenation, as well as microstructure and the interstitium. Medical imaging is becoming increasingly important in the evaluation of kidney physiology and pathophysiology, showing promise in management of patients with renal disease, in particular with regard to diagnosis, classification, and prediction of disease development and progression, monitoring response to therapy, detection of drug toxicity, and patient selection for clinical trials. A variety of imaging modalities, ranging from routine to advanced tools, are currently available to probe the kidney both spatially and temporally, particularly ultrasonography, computed tomography, positron emission tomography, renal scintigraphy, and multiparametric magnetic resonance imaging. Given that the range is broad and varied, kidney imaging techniques should be chosen based on the clinical question and the specific underlying pathologic mechanism, taking into account contraindications and possible adverse effects. Integration of various modalities providing complementary information will likely provide the greatest insight into renal pathophysiology. This review aims to highlight major recent advances in key tools that are currently available or potentially relevant for clinical kidney imaging, with a focus on non-oncological applications. The review also outlines the context of use, limitations, and advantages of various techniques, and highlights gaps to be filled with future development and clinical adoption.

Renal abscess caused by Panton-Valentine leukocidin-producing Staphylococcus aureus: report of an unusual case and review of the literature

BACKGROUND

Renal abscesses are rare and mainly caused by an ascending infection due to Gram-negative microorganisms. We report the first case of a renal abscess caused by Panton-Valentine leukocidin-producing Staphylococcus aureus in an immunocompetent patient, and we present a comprehensive review of the literature.

CASE PRESENTATION

A 20-year-old immunocompetent woman had a 2-month history of left-sided back pain, fever and urinary symptoms. Urinalysis showed leukocyturia (19,000/mm³) without bacteriuria. Intravenous cefotaxime treatment was initiated. A computed tomographic scan showed a large abscess in the left kidney. Computed tomographic percutaneous drainage was done and cultures of abscess and blood grew methicillin-susceptible Panton-Valentine leukocidin-producing Staphylococcus aureus. Treatment was switched to cefazoline and then to clindamycin for 21 days. The patient quickly improved and the abscess was completely resolved 6 months after end of antibiotic treatment.

CONCLUSION

To our knowledge, this is the first report of a renal abscess caused by Panton-Valentine leukocidin-producing Staphylococcus aureus. Treatment with percutaneous drainage and an antibiotic with toxin inhibiting effect was successful.

COVID-19 pandemic impact on clinical outcomes of patients with obstructive pyelonephritis

Purpose

Obstructive pyelonephritis is a common urologic emergency that requires prompt decompression of the collecting system. The COVID-19 pandemic has changed patient flow and healthcare strategies at numerous emergency departments across Brazil with still unknown consequences for the population. This study sought to investigate the impact of the COVID-19 outbreak on clinical outcomes in patients with acute obstructive pyelonephritis at a tertiary academic center.

Materials and methods

After Institutional Review Board approval, a retrospective chart review of patients who required decompression of the collecting system due to acute obstructive pyelonephritis from June 2019 to July 2020 was conducted. Basic demographic information, pre-operative, and peri-operative data were recorded. Patients were assigned in “Pre-Covid” and “Post-Covid” groups based on the admission dates.

Results

A total of 63 patients were included, with 40 patients in the Pre-Covid group and 23 in the Post-Covid group. Patients from the Post-Covid group presented at the ER later after symptoms onset (7.8 vs. 4.3 days; p = 0.012), had higher rates of SIRS (57% vs. 25%; p = 0.012), perirenal abscesses (13% vs. 0%; p = 0.019), overall complications (p = 0.047) and presented longer hospital length of stay (7.6 vs. 3.8; p = 0.007).

Conclusion

During the COVID-19 pandemic, patients with acute obstructive pyelonephritis presented later for evaluation at the ER, had higher disease severity and longer hospital length of stay when compared to the pre-COVID group of patients with the same pathology.

Abscesos renales en pediatría: reporte de caso

Los abscesos renales y perirrenales hacen parte de un grupo de infecciones poco frecuentes en pediatría que comprometen el parénquima renal y el espacio perinefrítico. Estas entidades no tienen una clínica específica y, por lo tanto, se deben sospechar en todos los pacientes con infección urinaria que no respondan a la terapia antimicrobiana adecuada. De su apropiado diagnóstico dependerá la evolución y el pronóstico del paciente. Si bien el drenaje percutáneo mediante radiología intervencionista es un procedimiento descrito para el tratamiento de esta patología en los adultos, este puede hacer parte del manejo en pediatría. En este artículo, se presenta el caso clínico de un niño de tres años con diagnóstico de absceso renal y su manejo en un centro pediátrico de Bogotá, junto a una revisión actualizada de esta patología.