SEARCH · PubMed Health

Results for “Pyelonephritis”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 721 records · Page 40Linked to original sources

PubMed1982

Effect of iron on acute pyelonephritis and later chronic changes.

Administration of iron to rats exacerbated early inflammatory changes of pyelonephritis produced by intravenous inoculation of Escherichia coli. This effect was noted with four of eight strains of E. coli tested and was dependent on bacterial inoculum. Despite this increase in severity of acute pyelonephritis as judged by numbers of bacteria in the kidney and careful gross and microscopic evaluation, there was no enhancement of chronic changes seen 6 months later.

Abscess↗

PubMed1984

Pyelonephritis: the role of cell-mediated immunity defined in a congenitally athymic rat.

Thymus-derived lymphocytes (T-cells) have been shown to be present in the inflammatory infiltrate in renal infection but their role in host defense mechanisms has not been defined. Indirect evidence suggested that T-cells contributed to host protection but selective depletion of T-cells did not influence the course of pyelonephritis. In the present report, the characteristics of the athymic New Zealand nude rat (rnunz), which lacks T-lymphocytes, are detailed. This mutant was then used to assess the effect of an absence of T-cells on the bacteriological and histopathological features of pyelonephritis. No significant differences in the bacteriological course of the disease were found. Apart from fewer lymphocytes in the kidney lesions of nude rats and a slight, lag in the resolution of these lesions, no differences were observed in the histopathological course either. These observations, which have analyzed the quantitative relationship between cell-mediated immunity (CMI) and host resistance to renal infection, have shown that a gross reduction in CMI does not affect host resistance once bacteria have gained access to the kidney.

Animals↗

PubMed1986

Benefit from high intrarenal levels of gentamicin in the treatment of E. coli pyelonephritis.

The importance of high intrarenal levels of gentamicin on the outcome of experimental pyelonephritis was studied in rats receiving either a short course (three days) of gentamicin (G) alone or combined with a longer course (14 days) of ampicillin (A), cephalothin (C), or trimethoprim (T), or two weeks of therapy with ampicillin, cephalothin, trimethoprim and gentamicin given alone. While ampicillin, cephalothin and trimethoprim were undetectable in the medulla within six hours of cessation of therapy, gentamicin was still detectable in levels six folds above the MIC up to six months after treatment had ceased. Six months after the end of treatment, the percentage of sterile left kidneys in animals treated with ampicillin (50%), cephalothin (15%), trimethoprim (20%) was lower than the percentage of animals receiving 14 days of gentamicin (100%), or the combinations AG:89%, CG:67% and TG:60%, P less than 0.01. Following three days of gentamicin, 50% of the left kidneys were sterilized. When compared to ampicillin, cephalothin or trimethoprim alone, combined therapies significantly reduced the number of CFU in the kidneys P less than 0.01. These combinations were almost as effective as two weeks of therapy with gentamicin. Short-term therapy (three days) with an aminoglycoside which concentrates in the renal parenchyma, combined with an antibiotic which will accumulate in other parts of the nephron, may result in "pharmacological synergy". This new approach to therapy of pyelonephritis may be promising.

Acute Disease↗

PubMed1989

Ascending pyelonephritis in young rats retards kidney growth.

Several radiological studies have suggested that pyelonephritis in infancy and childhood may result in kidney growth retardation without renal scarring. In the present study, we induced ascending pyelonephritis in 20-day-old rats with intravesical infusion of E. coli. Four days after infusion, E. coli was cultured from all renal cortex. The rats were either left untreated (PNu) or were treated with trimethoprim-sulfa (PNt). The rats were investigated one month after infection and compared with an age-matched control group (C). Seventy-nine percent of the PNu rats had recovered spontaneously from infection. Body weight was the same in all groups. In PNu rats, kidney weight (KW), kidney area (KA) and glomerular filtration rate (GFR) were significantly decreased. KW, KA and GFR were similar in PNt and C rats. The numbers of filtering nephrons were not reduced by the infection. The total cortical DNA content (index of cell number) was significantly lower in PNu (5.30 +/- 0.32 mg) and PNt (6.62 +/- 0.44 mg) than in C rats (8.48 +/- 0.49 mg). The cortical DNA content was significantly lower in PNu than in PNt rats. The cortical protein/DNA ratio was significantly higher in PNu rats than in C rats. The protein/DNA ratio was similar in PNt and PNu rats. The increase in protein/DNA ratio was interpreted as a sign of cell hypertrophy. The inflammatory process as such did not increase the protein/DNA ratio. The kidneys were also examined for structural lesions. Signs of scarring, inflammation and cell necrosis were almost absent in all groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Aging↗

PubMed1989

Frequency of development of early cortical scarring in acute primary pyelonephritis.

Fifty-five cases of primary (that is, without urinary tract abnormalities), acute pyelonephritis (PN) were studied by computed tomodensitometry (CT). There were 48 women and 7 men. All were febrile and 16 had positive blood cultures. In 7 cases, (4 diabetics and 3 malnourished alcoholics) PN was painless, diagnosis was delayed and lesions were severe. Two diabetics underwent emergency nephrectomy for sepsis. Conventional radiological techniques (IVP and ultrasonography) were poorly informative. In contrast, initial CT abnormalities were visible in 44 patients. They consisted of triangular or round hypodense images, diffuse hypodensity in a grossly swollen kidney, and/or abscesses. Hypodense images were presumably due to acute focal ischemia. Renal histology was available in five patients. It showed acute interstitial nephritis with leukocyte infiltrates, edema and hemorrhagic streaks. Pyelonephritis was due to E. coli in 48 cases (87.5%). In 27 cases E. coli isolates were studied by genotypic assays which detect the three most frequent (pap, afa and sfa) of the four operons known to encode adhesin. In all cases, at least one of these genotypic markers of uropathogenicity was found. In 27 cases, repeat CT was done shortly after treatment. It showed healing in only 12. Early cortical scar formation was visible in 2. Final evaluation in 27 cases with adequate follow-up showed that (in addition to the 2 patients who had been nephrectomized), in only 17 of 27 (63%) had the kidneys recovered a normal appearance. In two cases one kidney had undergone atrophy; renal biopsy showed subacute-chronic interstitial nephritis.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Disease↗

PubMed1997

Pyelonephritis provokes growth retardation and apoptosis in infant rat renal cortex.

Childhood pyelonephritis is a common cause of renal cortical scarring and hypoplastic kidneys. To understand the mechanisms underlying the cortical lesions, urinary tract infection was induced in three-week-old rats by an intravesical infusion of E. coli, type 06 K13 HL a rat nephropathogenic strain. Four days after infection, histopathological examination showed marked infiltration of leukocytes in the medullary tissue adjoining the calyces and pelvis. In the cortex, signs of inflammation were found only in the cortical zone adjacent to the pelvis. No cells indicative of inflammation were observed in other parts of the cortex. Immunohistochemistry for endogenous proliferating cell nuclear antigen (PCNA) demonstrated a marked decrease in immunoreactivity in proximal tubular (PT) cells. The mitotic response of PT cells, assessed by 3H-thymidine autoradiography, showed a highly significant decrease during the first four days after induction of the infection. Four days after infection, a transient increase in apoptotic cells was observed in cortical cells outside the inflammatory areas. No increase in apoptotic cells was detected in the cortex 10 days after infection. Only a few apoptotic cells were detected in the control kidneys. In conclusion, the data indicate that inhibition of cell proliferation and enhancement of apoptosis may contribute to the renal parenchymal loss after childhood pyelonephritis.

Animals↗

PubMed2006

The urokinase plasminogen activator receptor is crucially involved in host defense during acute pyelonephritis.

The urokinase plasminogen activator receptor (uPAR) is expressed at the cell surface of inflammatory cells and plays an important role in neutrophil migration. To investigate the in vivo role of uPAR during urinary tract infection, acute pyelonephritis was induced in uPAR-/- and wild-type (WT) mice by intravesical inoculation with 1 x 10(9) colony-forming units (CFU) of uropathogenic Escherichia coli. Mice were killed after 24 and 48 h, after which bacterial outgrowth and cytokine levels in kidney homogenates were determined. Influx of neutrophils was quantified by myeloperoxidase-enzyme-linked immunosorbent assay. uPAR-/- kidneys had significantly higher numbers of E. coli CFU, accompanied by higher levels of interleukin-1beta (IL-1beta), IL-6, keratinocyte-derived chemokine (KC), macrophage inflammatory protein-2 (MIP-2), and tumor necrosis factor-alpha (TNF-alpha). However, the number of infiltrating neutrophils was similar in uPAR-/- and WT mice at both time points, suggesting that uPAR-/- neutrophils have a lower ability to eliminate E. coli. To further investigate this, neutrophil oxidative burst and phagocytosis was measured. The generation of reactive oxygen species upon stimulation with E. coli was not diminished in uPAR-/- neutrophils compared with WT. Interestingly, uPAR-/- neutrophils displayed significantly impaired phagocytosis of E. coli organisms compared with WT neutrophils. We conclude that uPAR is crucially involved in host defense through phagocytosis during E. coli induced acute pyelonephritis.

Animals↗

PubMed2000

Renal cytokine responses in acute Escherichia coli pyelonephritis in IL-6-deficient mice.

The aim of this study was to investigate the influence of IL-6 on mortality, bacterial growth and cytokine expression in experimental acute pyelonephritis. Female IL-6-deficient mice and their wild-type counterparts, 8-10 weeks old, were infected with Escherichia coli CFT 073 or injected with NaCl 0.9% (w/v) via the urethra and thereafter obstructed for 6 h. Animals were killed at 48 h, 6 days or 8 weeks and cytokine and bacterial renal levels were assessed at each time point. We found that IL-6-deficient mice had increased mortality and extensive renal bacterial growth on day 6, compared with wild-type mice (P < 0.05) and the histopathological changes were generally more severe and widespread in the IL-6-deficient mice. Peak mRNA expression of IL-1beta, IL-4, IL-10, IL-12 and interferon-gamma (IFN-gamma) occurred 48 h after infection in both IL-6 knock out and wild-type mice. Transforming growth factor-beta (TGF-beta) levels also peaked at 48 h in E. coli-infected wild-type mice, while in the IL-6-deficient strain both TGF-beta mRNA and protein levels were significantly lower at 48 h than wild-type levels (P < 0.0008 and P < 0.03, respectively) and remained stationary throughout the study period. Animals injected with NaCl 0.9% (w/v) displayed a similar decrease in TGF-beta expression (P < 0.02). When splenocytes from the IL-6-deficient mice were incubated with murine recombinant IL-6, TGF-beta levels increased to those of wild-type mice. No increase was observed when splenocytes from wild-type mice were incubated with the same doses of rIL-6. We therefore conclude that IL-6 plays an important role in bacterial clearance and directly influences the TGF-beta levels in experimental acute pyelonephritis. We also demonstrate that urethral obstruction per se induces an increase in TGF-beta the magnitude of which is decreased in IL-6-deficient mice.

Animals↗

PubMed2003

Enhanced chemokine response in experimental acute Escherichia coli pyelonephritis in IL-1beta-deficient mice.

The aim of the present study was to investigate the effects of IL-1beta and Escherichia coli on the expression and secretion of MIP-2, the mouse equivalent to human IL-8, MCP-1 and RANTES in the kidneys of mice with acute pyelonephritis. Female Bki NMRI, as well as IL-1beta deficient mice and their wild-type littermates, were transurethrally infected with either E. coli CFT 073 or injected with NaCl 0.9% (w/v) and thereafter obstructed for 6 h. The Bki NMRI mice were killed at 0, 24, 48 h and 6 days and the IL-1beta-deficient mice at 48 h. Chemokine mRNA and protein levels peaked at 24 h for the tested chemokines with the mRNA expression localized in the tubular epithelial cells and for MIP-2 also in neutrophils. Obstruction per se, also induced a chemokine expression similar to E. coli infection although at a lower level. Interestingly, MIP-2 levels were higher in the IL-1beta deficient mice as compared with the wild-type littermates. Likewise, the inflammatory changes were more frequent and, when present, more widespread in the IL-1beta-deficient mice than in the wild-type mice. Stimulation of a human renal tubular epithelial cell line (HREC), A498 and of primary human mesangial cells (HMC) with the same bacterial antigen depicted gene expression of the same chemokines. A rapid release of IL-8 and MCP-1 was observed from both cell types. RANTES response was delayed both in the HREC and the HMC. We conclude that acute E. coli pyelonephritis induces a MIP-2/IL-8, MCP-1 and RANTES expression and secretion localized primarily to the epithelial cells and that this production is confirmed after in vitro stimulation with the same bacterial antigen of human epithelial and mesangial cells. Blockade of induction of chemokine response may thus be an attractive target for possible therapeutic intervention.

Acute Disease↗

PubMed2003

Emphysematous pyelonephritis and renal amoebiasis in a patient with diabetes mellitus.

Emphysematous pyelonephritis is an uncommon and life-threatening infection of the kidney that is characterized by gas formation within or around the kidney and is associated with diabetes mellitus and urinary tract infection. Amoebiasis is a protozoal infection caused by Entamoeba histolytica. In its invasive forms, the disease is characterized by visceral abscess formations. We present a case of concomitant emphysematous pyelonephritis and renal amoebiasis in a 42-year-old female with uncontrolled diabetes mellitus. The patient did not respond well to initial supportive treatment and antibiotherapy. Therefore, nephrectomy was performed. She did extremely well after the operation and was discharged with antidiabetics and antibiotics.

Adult↗

PubMed1999

The role of vitamin A in preventing renal scarring secondary to pyelonephritis.

OBJECTIVE: To evaluate the efficiency of exogenously administered vitamin A in preventing renal scarring caused by experimental pyelonephritis in rats. MATERIALS AND METHODS: Forty Wistar rats were injected with 0.1 mL of solution containing Escherichia coli (1010 /mL) into both renal medullae. Five equal groups were then formed: group 1 was treated only with ciprofloxacin (30 mg/kg per day, twice daily, intraperitoneally) for 5 days, starting 3 days after bacterial inoculation; in group 2, 60 kIU of vitamin A was injected intramuscularly with the bacterial inoculation; in group 3, 60 kIU of vitamin A was injected similarly, but 3 days after bacterial inoculation; in group 4, 60 kIU of vitamin A was given orally with the bacterial inoculation; and group 5 was treated with ciprofloxacin for 5 days and vitamin A intramuscularly from the third day after bacterial inoculation. All the rats were killed 6 weeks after bacterial injection; blood samples were obtained to determine serum vitamin A and beta-carotene levels, and both kidneys were examined pathologically for scarring, graded as 0 (none), 1 (mild), 2 (moderate) and 3 (severe). RESULTS: Serum vitamin A levels were higher in the rats given vitamin A (group 2-5) than in group 1, being highest in group 4, although only this group had significantly higher levels of vitamin A than group 1 (P<0.05). Histopathologically, the fibrosis was mildest in groups 2 and 4 (two of 16 kidneys grade 1), whereas it was most severe in group 1 (all 16 grade 2-3). Fibrosis was significantly less in groups 2-5 than in group 1 (P<0.05). There was a significant negative correlation between vitamin A levels and the sum of the fibrosis, inflammation and tubular atrophy scores of all rats (r=-0.391, P<0.02). beta-carotene levels were unrelated to renal scarring. CONCLUSION: The administration of vitamin A could have a role in preventing renal scar formation from pyelonephritis induced experimentally in rats.

Animals↗

PubMed2000

Successful medical treatment of acute bilateral emphysematous pyelonephritis.

Emphysematous pyelonephritis most often presents as an acute medical emergency, typically in a septic diabetic patient with acute renal failure. The management of this condition has traditionally been surgical, with nephrectomy. However, some recent reports have described successful medical interventions. We describe a case of acute bilateral emphysematous pyelonephritis in a frail patient not suitable for bilateral nephrectomy and long-term dialysis. This condition was managed medically, not surgically, with intensive antibiotic and circulatory support. The outcome was complete recovery after months of hospital-based treatment. We discuss the management of this rare but important condition in detail.

Acute Kidney Injury↗

PubMed2000

Xanthogranulomatous pyelonephritis in childhood: a rare but important clinical entity.

PURPOSE: Xanthogranulomatous pyelonephritis (XGPN) is extremely rare in children. The authors review their experience of this condition. METHODS: Medical records were investigated to conduct a retrospective study of 4 patients with XGPN (3 boys, 1 girl; age range, 2 months to 7 years) at the authors' institute over the past 14 years. RESULTS: Three of the 4 patients presented with fever of unknown origin and 1 with general fatigue. An abdominal mass was palpable in two cases at initial presentation. Although all patients had pyuria or hematuria, preoperative urine culture was positive in only 2 cases. Preoperative radiologic studies showed that 1 kidney was affected completely in 2 cases and affected partially in 2 cases. Preoperatively, the provisional diagnosis was XGPN in 3 cases, and Wilms' tumor in 1 case. Total nephrectomy was performed in 3 cases and enucleation in 1 case. XGPN was confirmed in all cases by histopathologic studies, but the underlying disease could be identified only in 1 case (cystinuria). All patients did well postoperatively and have had no further health problems over a mean follow-up period of 4.8 years. CONCLUSIONS: XGPN should be considered when there is a history of recurrent or therapy-resistant pyelonephritis. Preoperative radiologic investigation is paramount for diagnosis, and nephrectomy is the treatment of choice, although partial resection or enucleation are adequate for partially affected kidneys.

Child↗

PubMed2000

Xanthogranulomatous pyelonephritis presenting as a pseudotumor in a 2-month-old boy.

The authors report on a 2-month-old boy presenting with a right renal mass. Investigations including ultrasound scan and computed tomogram were suggestive of a renal tumor. A right nephrectomy was performed with great difficulty because of dense adhesions to the adjacent structures. Cut section of the specimen showed the entire kidney to be replaced by cheesy-yellow areas. Histological examination was suggestive of xanthogranulomatous pyelonephritis. Although rare at this age, xanthogranulomatous pyelonephritis should be considered in the differential diagnosis of a renal mass in children. The lesion is unique among the inflammatory conditions in closely mimicking renal tumours clinically. A thorough histological examination also is suggested because the features can get confused easily with those of renal tumors.

Diagnosis, Differential↗

PubMed2002

Xanthogranulomatous pyelonephritis in children: diagnostic and therapeutic aspects.

BACKGROUND: Xanthogranulomatous pyelonephritis (XGP) is an uncommon chronic, inflammatory disease of the kidney. Etio-pathogenesis, diagnosis and management of pediatric XGP is still obscure due to the limited number of cases. Therefore, a retrospective clinical study was carried out to present an updated picture of the entire spectrum of pediatric XGP based on our 30 years' experience covering one of the largest non-collected series treated in a single medical center. METHODS: Records of children who were treated for XGP in our unit from 1970 to 1999, inclusive, were reviewed retrospectively. Information recorded for each patient included age, sex, past medical history, clinical characteristics, diagnostic procedures,treatment methods, histopathologic findings and outcome. RESULTS: 17 children with a mean age of 6.6 +/- 0.8 years, consisting of 15 males and 2 females, were treated for XGP. Eight patients had a urological disease history and 4 of them underwent surgery for urinary calculi and exstrophia vesica repair. The most common presenting symptoms were abdominal pain, fever,weight loss and anorexia. Palpable flank mass was the most common physical examination finding. Left and right kidneys were involved in 10 and 7 patients, respectively. Diagnostic procedures were intravenous pyelography, retrograde pyelography, ultrasound scan and computerized tomography (CT). Renal calculi and/or calcifications and non-functioning kidney were the most frequent findings in radiologic investigations. By combining all these investigations, the preoperative diagnoses were XGP (n = 2), renal and/or perirenal abscess (n = 5), psoas abscess(n = 2), non-functioning kidney due to recurrent pyelonephritis(n = 4), Wilms' tumor and/or renal clear-cell carcinoma (n = 4). XGP was correctly diagnosed in only two patients based on cr findings. Drainage of the renal or psoas abscess was performed in 8 patients as an initial procedure (surgical drainage in 6 and ultrasound-guided percutaneous drainage in 2 patients). Surgical procedures included nephrectomy (n= 13), partial nephrectomy (n=2), nephrectomy and diversion of reno-colic fistula(n= 1), and renal biopsy and nephrostomy (n= 1). Operative and postoperative complications were colonic perforation (n= 3) and wound infection (n = 3). Complications were noted only in patients who underwent nephrectomy without initial drainage procedures. Histopathologic examinations showed diffuse and focal XGP in 14 and 3 patients, respectively. CONCLUSION: XGP should be included in the differential diagnosis of all children presenting with perirenal or psoas abscess, renal mass and/or non-functioning kidney associated with/or without urolithiasis. Clinical awareness and a high index of suspicion is required to achieve the correct preoperative diagnosis and appropriate management. CT seems to be the most valuable imaging method for the diagnosis. We strongly recommend percutaneous drainage of the abscess and adjunctive antibiotic therapy prior to nephrectomy to avoid complications. Complete nephrectomy is the proper treatment for the diffuse form whereas frozen section biopsies followed by partial nephrectomy are mandatory for the proper treatment of focal disease.

Adolescent↗

PubMed1994

Gentamicin levels in pregnant women with pyelonephritis.

This study was performed at University Medical Center, Lubbock, Texas, from July 1989 to June 1990. We obtained serum gentamicin peak and trough levels in 23 pregnant women with pyelonephritis. The patients were given a loading dose of 2 mg/kg gentamicin, followed by 1.5 mg/kg gentamicin adjusted for obesity every 8 hours. Peak levels were obtained 1 hour after the fifth dose and trough levels were drawn 30 minutes before the sixth dose. Statistical analysis was performed using chi 2 analysis. The mean (+/- SD) peak gentamicin level was 2.7 +/- 1.4 micrograms/mL and the mean trough level was 0.5 +/- 0.3 micrograms/mL. Twenty-two of 23 (96%) patients had peak levels 5 micrograms/mL and 1 of 23 (4%) patients had peak levels between 5 and 10 micrograms/mL. The mean peak gentamicin level in pregnancy is significantly less than in puerperal women (2.70 versus 5.78; P < 0.000001). We conclude that the majority of pregnant women treated for pyelonephritis with standard doses of gentamicin do not achieve therapeutic levels. Also, peak gentamicin levels are significantly below that reported for puerperal women.

Adult↗

PubMed1987

Acute pyelonephritis in pregnancy.

There were 107 episodes of pyelonephritis associated with pregnancy or the early puerperium occurring in 103 gravidas investigated retrospectively for information concerning prematurity, low birthweight, and antibiotic susceptibility patterns in the recovered microorganisms. No difference was found in the incidence of prematurity on low birthweight between that group and a control group of gravidas from the same population. Members of the Enterobacteriaceae genus were the most common bacterial isolates from the urine, with a large portion of E. coli being resistant to both ampicillin (33%) and cephalothin (13%). Treated pyelonephritis associated with pregnancy does not appear to predispose to prematurity or low birthweight in this population. Also, initial therapy with a first-generation cephalosporin may no longer be appropriate, because a significant number of isolates (11%) were resistant to cephalothin.

Adolescent↗

PubMed1995

[Xanthogranulomatous pyelonephritis with phlegmonous abdominal wall infiltration. Diagnosis and assessment of extent via computerized tomography].

A 34-year-old woman who 14 years previously had undergone a left nephrotomy for nephrolithiasis complained of pain in the left renal fossa which was reddened and painful on percussion. She had a fever of 38.2 degrees C. C-reactive protein was raised to 80 mg/l, the white cell count to 14,620/microliters (83% neutrophils). Protein and white cells were found in the urine together with a significant number of E. coli on urine culture. Plain film of the abdomen showed a staghorn calculus and ultrasonography demonstrated renal enlargement with a possible paranephritic abscess. The computed tomography diagnosis was xanthogranulomatous pyelonephritis, on the basis of renal enlargement, staghorn calculus, hypodense areas with typical density values (10-15 Hounsfield units), contrast enrichment and extrarenal extension of partly phlegmonous partly fused-together inflammatory changes. The abscessing parts were drained under computed tomography control. Starting 7 days pre-operatively the patient had been receiving ciprofloxacin (0.4 g daily) intravenously. A nephrectomy had to be performed subsequently. Antibiotic treatment was discontinued 2 weeks later and she was discharged symptom-free. The diagnosis of diffuse xanthogranulomatous Pyelonephritis was confirmed by histological examination of the surgical specimen.

Abdominal Abscess↗