Clinical characteristics and risk factors of acute focal bacterial nephritis in children / 中华肾脏病杂志

Objective:To summarize and analyze the clinical features and risk factors of acute focal bacterial nephritis (AFBN) in children.Methods:It was a retrospective cohort study. The clinical data of patients diagnosed with upper urinary tract infection in Children's Hospital Affiliated to Capital Institute of Pediatrics from July 1, 2016 to July 31, 2021 were collected, and the patients all received abdominal enhanced CT examination. According to the imaging examination results, the patients were divided into AFBN group and acute pyelonephritis (APN) group, and the clinical manifestations, laboratory and imaging examination between the two groups were compared. Logistic regression model and receiver operating characteristic curve were used to analyze the risk factors of AFBN.Results:A total of 135 patients with upper urinary tract infection were enrolled in this study, with age of 2.5 (0.5, 3.7) years old, and 68 males (50.4%). There were 67 patients (49.6%) in AFBN group and 68 patients (50.4%) in APN group. There were statistically significant differences in the highest fever temperature, duration of fever after treatment, proportion of lower urinary tract irritation symptoms, proportion of urinary tract malformation or abnormality, white blood cell count, neutrophil count, procalcitonin, C-reactive protein, proportion of pyuria, urinary β2 microglobulin and proportion of using carbapenem antibiotics between the two groups (all P<0.05). Multivariate logistic regression analysis result showed that urinary tract malformation/abnormality ( OR=3.34, 95% CI 1.23-9.10) and leukocytosis ( OR=1.25, 95% CI 1.03-1.51) were the independent risk factors of AFBN. Conclusions:The children with urinary tract infection who have high peak fever, long duration, obvious increase of inflammatory indexes and urinary β2 microglobulin may suggest AFBN. Urinary tract malformation/abnormality and high white blood cells are risk factors of AFBN.

Comparative analysis of clinical characters between acute focal bacterial nephritis and acute pylonephritis / 中华肾脏病杂志

Objective To improve standards of diagnosis and therapy for acute focal bacterial nephritis bY comparing the characters of acute focal bacterial nephritis and acute pylonephritis.Methods Thirty-five patients of upper urinary tract infection whoever accepted ultrasonographic and computed tomographic (CT) examinations in Beijing Hospital from January 2007 to January 2013 were studied retrospectively.Eighteen patients were diagnosed as acute focal bacterial nephritis (AFBN) according to CT imaging features,the other 17 patients were diagnosed as acute pyelonephritis (non-AFBN).The clinical feature,laboratory and imaging examination were compared between the two groups.Results Leukocyte count,percentage of neutrophil,fasting blood-glucose,ESR,NAG/Cre of urine,the combination of more than one kind of antibiotics and duration of antibiotic treatment were higher or much more in AFBN group patients than non AFBN patients,the differences between two groups were statistical significance(P ＜ 0.05).Urine microorganism culture was mainly Escherichia coli no matter in AFBN group or non-AFBN group,microorganism species of AFBN patients were more complex than non-AFBN patients.The most common contrast-enhanced CT feature of AFBN included local distribution of inflammatory area,wedge-shaped or unregular-shaped hypodense lesions on bilateral or single kidney,and mass-like hypodense lesions in more severe cases.NAG/CRE of urine was higher in AFBN group patients with bilateral kidney lesions than with single kidney lesions and non AFBN patients.The remission time of AFBN and non-AFBN was (3.4 ± 2.9) d,(3.0 ± 1.8)d respectively.The relapsing rate of AFBN and non-AFBN within half a year was 2/18,2/17,respectively.Conclusions The symptoms of acute focal bacterial nephritis are not specific.Abdominal contrast-Enhanced CT,ESR,leukocyte count,urine NAG/CRE are probably a predictor of AFBN.Antibiotic treatment with appropriate usage and sufficient duration could bring satisfactory outcomes and prognosis in acute focal bacterial nephritis and pyelonephritis patients.

Clinical Characteristics and Renal Outcomes of Acute Focal Bacterial Nephritis in Children

PURPOSE: This study was performed to elucidate the clinical pictures of acute focal bacterial nephritis(nephronia) in children. METHODS: We reviewed 9 children with nephronia diagnosed by ultrasonography or computed tomography of kidneys from September 1994 to August 2004. RESULTS: The overall male to female ratio was 2:1, and the age distribution ranged from 0.1 to 6 years(mean 2.8+/-2.2). The cardinal symptoms were fever, chills, abdominal pain and dysuria/frequency. The initial leukocyte count was 21,000+/-5,600/uL; ESR, 60+/-23 mm/hr; CRP, 17+/-10 mg/dl. Pyuria was noted in every patient and persisted for 10.5+/-7.8 days after antimicrobial treatment. Abdominal sonography demonstrated focal lesion of ill-defined margin and low echogenicity in 5 of 9 patients(55.6%), while computed tomography revealed nonenhancing low density area in all patients(100%). Three of 9 patients(33.3%) had vesicoureteral reflux, greater than grade III. The initial (99m)Tc-DMSA scan showed one or multiple cortical defects in every patient, and improvements were noted in 2(33.3%) of 6 patients who received follow up scan after 4 months. Intravenous antibiotics was given in every patient under admission. Total febrile period was 11.8+/-6.3 days(pre-admission, 4.0+/-3.0; post-admission, 7.8+/-5.5 days) and the patients needed hospitalization for 17.2+/-8.1 days. CONCLUSION: For the early diagnosis of 'acute focal bacterial nephritis' we should perform renal computed tomography first rather than ultrasonography, when the child has toxic symptoms and severe inflammatory responses in blood and urine.

A Clinical and Radiologic Study of Acute Focal Bacterial Nephritis in Children

PURPOSE: To raise awareness of the clinical importance of, and the need for proper management of acute focal bacterial nephritis(AFBN), we analyzed 22 AFBN patients and 22 other upper urinary tract infection patients by use of comparative studies. METHODS: From January 2000 to May 2002, 22 AFBN patients aged from 1 month to 12 months were selected. As a control group, 22 UTI patients with no radiologic abnormalities were selected and matched by age and sex. RESULTS: The incidence of AFBN was more common in boys than in girls. Since both groups had similar symptoms, it was difficult to diagnose AFBN by clinical presentations alone. ESR and CRP were significantly higher in AFBN patients. The most common causative organism was E. coli in both groups. On the sonographic findings, the most lesions were seen on the upper lobe of the kidney; more frequently, on left kidney. The lesions showed globular or wedge-shaped increased echogenecity. 99mTc-DMSA scan showed the complete coincidence of the location, size and shape in all cases compared to the findings of renal sonography. CONCLUSION: The roles of renal sonography and DMSA scan were very important, and ultrasonography was an excellent initial tool in diagnosing AFBN. Since the degree of infection in AFBN is more severe than other urinary tract infections and evollution into a renal abscess is possible, early diagnosis and appropriate antibiotics therapy is essential.

A Case of Acute Bacterial Nephritis Diagnosed by Renal Biopsy / 대한신장학회잡지

Urinary tract infection is one of the causes of acute renal failure. But it has been reported rarely, so we must consider another etiologies before diagnosis. Abdominal ultrasonogram is a good non-invasive technique for radiologic diagnosis or for differential diagnosis, but it's possible that tiny abscesses and small lesions of focal bacterial nephritis might be missed. CT is the best radiologic method to diagnose renal lesion, especially acute bacterial nephritis. Nevertheless, CT has several problems, including contrast-induced nephropathy, exposure to radiation. We experienced a severe form of anuric acute renal failure secondary to acute bacterial nephritis due to E. coli infection. The patient's renal lesion was not visualized on the ultrasonogram and his uremic symptom was severe. So we decided to do a kidney biopsy to find another possible cause of acute renal failure. The renal biopsy finding showed acute bacterial nephritis, and abdominal CT reconfirmed it. His serum creatinine increased to a maximum 8.5 mg/dL, but decreased to 1.24 mg/dL through continuous antibiotic therapy. We emphasize that urinary tract infection is not a rare cause of acute renal failure any more, and that positive diagnositic approaches, including kidney biopsy, are important for accurate and early diagnosis.

Three Cases of Acute Focal Bacterial Nephritis

Acute focal bacterial nephritis(AFBN) is an unusual form of localized renal infection, which has various imaging findings and should be distinguished from abscess or other renal masses. Clinical symptoms are similar to other urinary tract infections but the diagnosis needs a CT or sonographic confirmation. Treatment, which is nonoperative, consists of intensive antibiotic therapy. We report three cases of AFBN with urinary tract infection in an 11-month-old, 9-month-old female and 8-month-old male patients, respectively. The confirmative diagnosis was done by localized intrarenal solid mass lesion by sonography. They were treated with intravenous and oral antibiotics for 6, 4 and 2weeks, respectively. Follow-up urinalysis, urine culture and sonographic finding were normal after treatment.

A case of acute focal bacterial nephritis complicated by acute renal failure / 대한내과학회지

Acute focal bacterial nephritis is a part of urinary tract infection and a special form of acute pyelonephritis. In most cases, it is treated well by antimicrobial therapy without severe complications. Unusual cases have been reported that renal failure and or chronic granulomatous interstitial nephritis was combined with acute focal bacterial nephritis. We describe a case of acute reanl failure complicated by acute focal bacterial nephritis in 30-year-old male. He was admitted to this hospital owing to fever, chilling, right flank pain. On admission, BUN and creatinine were 29 mg/dl, 1.8 mg/dl. Urinalysis showed leukocyturia, & bactriuria. Urine culture revealed E. coli over us. Abdominal CT and ultrasonography was represented focal hypodense area and diffuse renal enlargement so we could diagnose acute focal bacterial nephritis. The patient was improved with antimicrobial therapy and hydration. In conclusion, this case shows the possibility that unusual complication such as acute reanl failure can be happensed in acute focal bacterial nephritis in continum with acute pyelonephritis

Two cases of acute focal bacterial nephritis / 대한비뇨기과학회지

Acute focal bacterial nephritis (AFBN), synonymous with acute lobar nephronia (ALN) or focal pyelonephritis, is an inflammatory mass without liquefaction caused by severe acute bacterial infection of kidney. Unless treated effectively, progression to a renal abscees may ensue. Clinically, AFBN presents as acute pyelonephritis, and radiologically, as focal swelling or mass. The distinction between AFBN and renal abceess or even tumor may be confusing and difficult. Ultrasonography and computerized tomography(CT) aid in establishing the correct diagnosis. However, the appearance of AFBN on sonography and CT is by no means pathognomonic. Benign or malignant renal tumors may have a similar appearance. With the clinical history, a high index of suspicion, and follow-up studies after institution of medical treatment may further aid in the differentiation. Herein we report 2 cases of AFBN, which were presented as renal masses.