Renal abscess in children

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

Pediatric renal abscesses: A contemporary series

INTRODUCTION

Pediatric renal abscesses are an uncommon diagnosis, with a paucity of data comparing treatment modalities. Patient presentation ranges from persistent dull flank/abdominal pain with or without fevers, to those who are overtly ill, presenting with hemodynamic instability and bacteremia. Management for pediatric renal abscesses is typically based on results extrapolated from small series in adult cohorts, with conservative measures recommended when the lesion is <3 cm.

OBJECTIVE

This study evaluated the presentation, management and outcomes of a contemporary cohort of pediatric patients with renal abscesses.

STUDY DESIGN

A total of 16 consecutive pediatric patients with radiologically diagnosed intra-renal or peri-nephric abscesses from 1990 to 2012 were identified. Patients were identified by querying institutional records via ICD-9 and CPT codes referencing renal abscess. Charts were retrospectively reviewed to evaluate multiple clinical variables, including: presenting symptoms, size of abscess, management strategy and clinical outcomes. Clinical resolution was confirmed via repeat ultrasound or computed tomography.

RESULTS

The median age at presentation was 13 years (range 1 month-18 years) and 13/16 patients (81%) were female. Abscess formation was secondary to: urinary tract infection in 13 (81%); hematogenous seeding from a skin infection in one (6%); and an unknown etiology in two (12%) patients. The most common organism identified on urine culture was Escherichia coli (10, 77%). Hematogenous seeding was confirmed in only one case, with Staphylococcus aureus growing on culture from both a cutaneous lesion and percutaneous drainage of the renal lesion. Overall, abscesses were a median of 2.2 cm (IQR 2, 3.7), with 13 (81%) successfully managed with conservative therapy, including intravenous antibiotics, with resolution on repeat imaging at a median of 21 days (range 6-55). For patients presenting with abscesses ≤3 cm, conservative measures were employed in 10/11 cases, with 100% success rate. Three patients had larger abscesses (3.8, 4, and 10 cm), which resolved after treatment with percutaneous drainage. A voiding cystourethrogram was performed in 10 patients, with two (20%) detecting an abnormality (low-grade vesicoureteral reflux, which required no further intervention).

CONCLUSIONS

Pediatric renal abscesses were most commonly small and secondary to an E. coli UTI. Most small (≤3 cm) renal abscesses resolved with conservative management. Percutaneous drainage should be considered for lesions >3 cm and in patients who remain persistently febrile, despite culture-specific antibiotics, are immunocompromised or critically ill.

Pediatric renal abscess: a 10-year single-center retrospective analysis

OBJECTIVE

The objective of this retrospective series is to describe the demographics and treatment of patients with renal abscesses and to determine if abscess size influences management.

METHODS

We reviewed all pediatric cases of renal abscesses treated over a 10-year period in our medical center. Clinical, laboratory, imaging data, and treatment modalities were analyzed.

RESULTS

Thirty-six patients were evaluated, with renal abscesses found in all age groups. The median age was 9.3 years, and 64% of patients affected were female. Fever and abdominal pain were the most common clinical symptoms. A premorbid genitourinary condition was present in 310/a of patients. Previous urinary tract infection was documented in 31% of the cases. Initial elevation of C-reactive protein or erythrocyte sedimentation rate, when obtained, was observed in >80% of cases. Abnormal urinalysis was recognized in two-thirds of encounters. Escherichia coli, the most common microorganism isolated, was found in half the cases. Staphylococcus aureus was isolated in 11%. Ultrasound and computed tomography were the most used diagnostic imaging modalities. Eighty-nine percent of the patients who received intravenous antibiotics alone as an initial treatment regimen did not require percutaneous drainage or surgery.

CONCLUSIONS

Ten of the 14 patients with an abscess size > or =3 cm had an invasive intervention, but only 1 of these 10 had an initial 48-hour trial of antibiotics alone. In contrast, only 2 of the 22 patients who had an abscess size <3 cm received an invasive intervention (Fisher P= .0002). We conclude that conservative treatment with intravenous antibiotics may be a reasonable initial approach.

Conservative management of paediatric renal abscess

OBJECTIVE

Renal abscesses in the paediatric patient population are a rare entity. Patients are usually treated with percutaneous surgical drainage of the renal abscess as conservative treatment with broad-spectrum antibiotics is not considered as effective. We describe the conservative management of renal abscesses without percutaneous drainage in 6 children.

MATERIALS AND METHODS

Six patients with a median age of 31 months, admitted over a 6 year period at two medical centers, were retrospectively studied. All patients were treated conservatively.

RESULTS

In all patients, the abscesses were solitary, unilateral and located in the right kidney. The median abscess diameter was 38 mm. The diagnosis was made by ultrasonography. All 6 children were treated conservatively with a urinary catheter or suprapubic catheter and broad-spectrum antibiotics. None of the renal abscesses were surgically or percutaneously drained.

CONCLUSIONS

A series of 6 paediatric renal abscesses, all successfully treated without surgical intervention, is presented. We believe that, in carefully selected cases, renal abscesses can be managed without percutaneous drainage. Furthermore, all children had complete resolution of the abscess.

Bilateral renal abscess in a previously healthy 11-year-old girl

Renal abscesses are infrequently encountered in children. We describe a girl diagnosed with bilateral renal abscess. Although ultrasonography and computerised tomography are used to establish the diagnosis, in our case magnetic resonance imaging proved to be a useful additional diagnostic method. Using percutaneous aspiration, we were able to establish the correct diagnosis and identify the causative micro-organism. The patient was successfully treated with a combined intravenous and oral course of antibiotics. In conclusion, renal abscesses can occur in children without a history of reflux or urinary tract infection; this should be kept in mind when evaluating a child with fever. In addition, full recovery can be achieved solely with antibiotics.

Evolution of acute focal bacterial nephritis into a renal abscess

Acute focal bacterial nephritis (AFBN) is a localized bacterial infection of the kidney presenting as an inflammatory mass without frank abscess formation, which may represent a relatively early stage of renal abscess. The pathogenesis of AFBN is thought to be hematogenous infection or ascending infection from the lower urinary tract. For the majority of children, the pathogenesis may be related to ascending infection, because pre-existing malformative uropathy, especially vesicoureteral reflux (VUR), is common in pediatric patients. Few clinical reports have demonstrated the evolution of this condition into renal abscess in children. We report a girl with AFBN associated with VUR that evolved into a renal abscess despite appropriate intravenous antibiotic therapy. We undertook serial radiological observation of its evolution. It is important to differentiate AFBN from renal abscess because the management of the two entities may be different, and follow-up studies are indispensable to determine appropriate therapy.

Metastatic renal abscess mimicking Wilms' tumour

Renal abscesses are uncommon in children, and usually present with a high fever and flank pain. We report a 9-year-old girl who presented with abdominal pain and cough. While the finding of multiple lung nodules and a renal mass prompted the initial diagnosis of Wilms' tumour, biopsy showed multiple renal abscesses with secondary lung involvement. The imaging findings and pathology correlation are provided.

Percutaneous imaging-guided abdominal and pelvic abscess drainage in children

Percutaneous imaging-guided drainage is the first-line treatment for infected or symptomatic fluid collections in the abdomen and pelvis, in the absence of indications for immediate surgery. The technology and expertise needed to perform percutaneous abscess drainage are widely available and readily adapted for use in the pediatric population. Catheter insertion procedures include the trocar and Seldinger techniques. Imaging guidance for drainage is most commonly performed with ultrasonography (US), computed tomography, or US and fluoroscopy combined. Abscesses in locations that are difficult to access, such as those deep in the pelvis, subphrenic regions, or epigastric region, can be drained by using the appropriate approach-transrectal, transgluteal, intercostal, or transhepatic. Although the causes of abscesses in children differ slightly from those of abscesses in the adult population, the frequency of successful treatment with percutaneous abscess drainage in children is 85%-90%, similar to that in adults. With expertise in imaging-guided drainage techniques and the ability to adjust to the special needs of children, interventional radiologists can successfully drain most abscesses and obviate surgery. Successful adaptation of abscess drainage techniques for pediatric use requires attention to the specific needs of children with respect to sedation, dedicated resuscitation and monitoring equipment, avoidance of body heat loss, minimization of radiation doses, and greater involvement of family compared with that in adult practice.

[The association between human toxocariasis and pyogenic abscesses]

The association between hepatic abscesses and schistosomiasis mansoni was confirmed by clinical and experimental studies. Other parasites may cause systemic immunologic changes and local structural alterations in the affected organs that can facilitate the seeding of these areas by bacteria. Tropical pyomyositis, pyogenic liver and renal abscesses are frequent diseases in tropical areas. The visceral larva migrans syndrome is caused by the presence, in the human body, of larvae of worms that have other animals as their definitive host, most commonly being caused by Toxocara canis. The larvae migrate to various body organs leading to many inflammatory reactions in the form of granuloma and tissue necrosis. In this review we discuss the possible host-parasite-bacteria interactions that would favour the formation of abscesses in the organs involved by the larva of T. canis and present preliminary results of a clinical and experimental study undertaken during the last four years to define the role of this parasite in the pathogenesis of the abscesses.

Conservative management of a patient with bilateral renal abscesses

We present the case of a patient with no pre-existing systemic or renal disease who developed multiple, bilateral renal abscesses caused by infection with Escherichia coli. In view of the diffuse nature of his lesions the patient was not a candidate for percutaneous drainage or surgery. He made a full recovery following conservative antibiotic therapy.

Renal abscess in healthy children: report of three cases

We report three cases of renal abscess in otherwise healthy boys. One had a history of blunt trauma and two of antecedent skin infection. All presented with flank pain and fever. Urine and blood cultures were sterile. The diagnosis was made using ultrasound and computerized axial tomography. The first patient had recurrent renal abscess, following surgery and a short course of antibiotics. Eventually all responded well to long-term antibiotics only.