Vitamin E administration at the onset of fever prevents renal scarring in acute pyelonephritis

Demographic, clinical, and laboratory factors associated with renal parenchymal injury in Iranian children with acute pyelonephritis

Background

The association between renal parenchyma changes on dimercaptosuccinic acid (DMSA) scans and demographic, clinical, and laboratory markers was assessed in pediatric patients with acute pyelonephritis.

Methods

A retrospective study of 67 Iranian babies and children aged 1-month to 12-year with APN was conducted between 2012 and 2018. The presence of renal parenchymal involvement (RPI) during APN was determined using technetium-99m DMSA during the first 2 weeks of hospitalization. The association of DMSA results with demographic data, clinical features (hospitalization stay, fever temperature and duration), and laboratory parameters such as pathogen type, and hematological factors (ESR, CRP, BUN, Cr, Hb, and WBC) was evaluated.

Results

92.5% of children with an average age of 43.76 ± 5.2 months were girls. Twenty-four children (35.8%) did not have renal parenchymal injury (RPI), while 26 (38.8%) and 17 (25.4%) patients showed RPI in one and both kidneys, respectively. There was no significant association between RPI and mean ESR, CRP, BUN, and WBC. However, there were significant associations between RPI and higher mean levels of Cr, Hb, and BMI.

Conclusions

Low BMI and Hb levels and increased Cr levels might be indicative of the presence of RPI in children with APN.

Urinary carbohydrate antigen 19-9 level as a biomarker in children with acute pyelonephritis

Early and prompt diagnosis of pyelonephritis is of great importance in children. The aim of this study is to evaluate the diagnostic accuracy of urinary carbohydrate antigen 19-9 (CA19-9) levels for predicting acute pyelonephritis (APN) in children with urinary tract infection (UTI). Patients were allocated into two groups of APN and acute cystitis according to their diagnosis. Urine samples of all patients were collected. Also, complete history was taken, and physical examination, kidney and bladder ultrasonography, ^99mTc-dimercaptosuccinic acid renal cortical scintigraphy, and urine analysis and culture were performed. Urinary CA19-9 was measured by an electrochemiluminescence enzyme immunometric kit. In addition, CA19-9 levels were measured in the APN group 2 weeks and 3 months later. A total of 100 children were included in this study (mean age 46 ± 31 months, 16 males and 84 females). CA19-9 levels were significantly greater in the APN group than acute cystitis group (510 ± 328 vs. 18.7 ± 18.6 U/ml, P < 0.001). During follow-up periods of the APN group, CA19-9 levels decreased to 180 ± 124 U/ml after 2 weeks (P < 0.001) and 30 ± 23 U/ml after 3 months (P < 0.001). Urinary CA-19-9 had 95.3% sensitivity and 80% specificity for the diagnosis of APN. The area under the curve value of CA19-9 was 0.904 (95% CI 0.831-0.977).Conclusion: Urinary CA19-9 level can be used as a reliable biomarker for early detection of APN prior to urine culture confirmation in children with UTI. What is known: • Early and prompt diagnosis of pyelonephritis is necessary in children to prevent renal damage. • Acute pyelonephritis can present with vague and nonspecific symptoms in infants and children. What is new: • Urinary carbohydrate antigen 19-9 is a reliable biomarker for early detection of acute pyelonephritis prior to urine culture confirmation. • Urinary carbohydrate antigen 19-9 has 95.3% sensitivity and 80% specificity for diagnosis of acute pyelonephritis.

Prevention of Renal Scarring in Acute Pyelonephritis by Probiotic Therapy: an Experimental Study

We evaluated the protective effects of probiotic administration as a prophylaxis treatment and immediately after fever onset in increasing the immune response and decreasing the renal scarring in a rat model of acute pyelonephritis. Twenty-four rats were apportioned to three groups. In GI (n = 8), the rats were injected with direct inoculation of Escherichia coli into the right kidney. In GII (n = 8), the rats received a probiotic regimen 1 month before E. coli injection and the probiotic regimen was continued for the next 2 months. In GIII (n = 8), the probiotic regimen was started just after E. coli injection and was continued for 2 months. Technetium-99m-DMSA renal scan, histopathological evaluations, concentrations of CA19-9, IgA, blood urea nitrogen (BUN), and creatinine were assessed 1 and 2 months post-injection. It took an average of 4.2 ± 1.1 h between the injection and onset of fever in GI and GII. In GIII, this period was longer (7.5 ± 1.4). Probiotic administration resulted in reduction of interstitial fibrosis and tubular and glomerular atrophy in GII in all follow-ups. Technetium-99m-DMSA renal scan showed that the right kidney reached near the normal cortical integrity (47%) in GII compared to GI (32%) after 2 months of injection. However, the renal integrity did not improve significantly in GIII (41%). In GII, CA19-9 was lower (p < 0.05), while the levels of serum and fecal IgA were higher (p < 0.05). Administration of the probiotic regimen in the rat model may decrease renal damage in pyelonephritis. In spite of better results in the prophylactic group compared to the treatment group, no strong evidence was found to prove the advantage of its prophylactic application over the treatment administration.

Preventive Effect of L-Carnitine on Scar Formation During Acute Pyelonephritis: A Randomized Placebo-Controlled Trial

BACKGROUND

Urinary tract infection and pyelonephritis are clinical problems that frequently occur in children. Several factors are responsible for renal tissue injury, morbidity, and renal scarring after pyelonephritis. The aim of this study was to evaluate the preventive effect of L-carnitine on renal scarring in acute pyelonephritis.

METHODS

A randomized double-blind clinical trial was conducted on 65 children aged 6 months to 10 years. Patients were randomized into 2 groups to receive 7-day treatment with only antibiotics without L-carnitine (control group; n = 32) and 7-day treatment with L-carnitine (case group; n = 33) during the acute phase of infection. Technetium-99m-labeled dimercaptosuccinic acid (DMSA) scintigraphy was performed for all children during the acute phase (in 2-7 days of hospitalization) and late phase. P-value less than 0.05 was statistically significant.

RESULTS

We recruited 65 participants in the study: 32 children in control group and 33 children in case group. Three children in the control group and 2 children in the case group refused to perform the second DMSA scan. Overall, data analysis at the end of the study was done on 60 patients. Age distribution of girl patients with upper urinary infection was 6.5% in girl children aged between 6 months and 12 months, 41.1% aged between 1 and 5 years, 33.3% aged between 5 and 10 years, respectively. There was no significant difference between 2 groups in age and sex. There was no significant difference between 2 groups in systolic blood pressure, diastolic blood pressure, the lab data including urine white blood cells and serum erythrocyte sedimentation rate, and antibiogram profiles. Voiding dysfunction was detected in 10% of the participants. The baseline DMSA was not significantly difference in 2 groups, but worsening of kidney lesions was significantly higher in control group after 6 months (P = 0.012).

CONCLUSION

Our study showed that L-carnitine significantly decreased renal scarring because of acute pyelonephritis.

The role of nonautologous and autologous adipose-derived mesenchymal stem cell in acute pyelonephritis

We compared the therapeutic effects of autologous and nonautologous adipose-derived mesenchymal stem cell (ADMSC), in ameliorating the renal function in a rabbit model of acute pyelonephritis. The difference of perirenal and neck subcutaneous ADMSCs were also evaluated. Twenty female rabbits were apportioned to 5 groups. In group I (n = 4), the rabbits were injected direct inoculation of Escherichia coli (E. coli) into the right kidney. In group II (n = 4), autologous ADMSCs obtained from nape adipose tissue were injected into the subcapsular space 1 week after E. coli injection, while nonautologous ADMSCs of the same origin (from male rabbits) were applied in group III (n = 4). In group IV (n = 4), autologous perirenal ADMSCs were applied with the same method, while perirenal nonautologous ADMSCs from male rabbits were used in group V (n = 4). Technetium-99m-DMSA renal scan was performed 1, 2 and 4 months post-injection in all groups. Kidneys were excised for the evaluation of histopathological changes in the same time points. PCR examination for detection of Y-chromosome (in group III and V) and fluorescent evaluation (in group II and IV) were also performed to determine the fate of injected cells. Injection of autologous ADMSCs resulted in more satisfactory outcomes in reduction of interstitial fibrosis, tubular, and glomerular atrophy as compared to nonautologous groups. However, histopathological ameliorations were significantly better in group IV in which autologous perirenal ADMSC was applied. Remarkably, two months after the injection, Technetium-99m-DMSA renal scan showed that right kidney reached to near normal cortical function (48 and 45%) in group IV and V, respectively as compared to groups II (41%) and III (37%). Autologous ADMSCs may have better results in cell therapy as compared to nonautologous cells. However, more satisfactory outcomes may be obtained when the cell source is selected from the surrounding adipose tissue.

Use of antioxidants in urinary tract infection

Pyelonephritis is an inflammatory process, and oxidative stress plays a major role in it. Anti-inflammatory or antioxidant therapy given concomitantly with antibiotics should lower the risk of postpyelonephritic scarring. As the lack of review studies in the use of antioxidants in urinary tract infections was detected, this study was designed. We conducted a review of available articles in PubMed and Google Scholar with a simple review, using keywords of “antioxidant” and “pyelonephritis” with all their possible synonyms and combinations. Only interventional studies were collected. There were neither limitations on time, nor the location of the study, type of subjects, administration rout of the antioxidant drug, and the antioxidant drug used. After studying the abstracts or in some cases the full text of articles, they were categorized based on the type of antioxidant, type and number of subjects, rout of administration, dosing, duration of treatment, year of publication of the paper, and the results. A total of 66 articles published from 1991 to 2015 were found by studying just the title of the papers. Studying the abstracts reduced this number to 51 studies. Antioxidants used for this condition were Vitamins A, E, and C, cytoflavin, caffeic acid phenethyl ester, ebselen, allopurinol, melatonin, N-acetylcysteine, oleuropein, montelukast, oxytocin, ozon, dapsone, pentoxifyllin, tadalafil, bilirubin, cranberry, meloxicam, L-carnitine, colchicine, perfluoran, methylprednisolone, and dexamethasone. Studies show that antioxidants are capable of reducing oxidative stress and can be used effectively along with antibiotics to reduce the scar formation.

The effect of vitamin A on renal damage following acute pyelonephritis in children: a meta-analysis of randomized controlled trials

BACKGROUND

Renal scarring after acute pyelonephritis (APN) in children is of concern and in the worst cases leads to long-term cardiovascular morbidity. There are reports that vitamin A may alleviate renal damage following APN. We conducted a meta-analysis to investigate the role of vitamin A in the alleviation of renal damage.

METHODS

We searched PubMed, EMBASE, the Cochrane Central Register of Controlled trials (CENTRAL, the Cochrane Library) and the Wang Fang database (Chinese) from their inception to February 3, 2015 for randomized controlled trials (RCTs) investigating vitamin A and renal damage. Primary outcome was number of patients/kidneys with renal damage, defined as persistence of photopenic lesions based on technetium-99m dimercaptosuccinic acid renal scintigraphy. We calculated pooled relative risks for renal damage in the vitamin A group.

RESULTS

Four RCTs, involving a total of 248 patients aged 1-144 months (120 in experimental group, 128 in control group), were included in the meta-analysis. Vitamin A was inversely associated with renal damage (relative risk 0.53, 95 % confidence interval 0.43, 0.67) when compared with placebo group after an average follow-up of 5 months.

CONCLUSIONS

Current evidence indicates that vitamin A may exert a preventive effect on renal damage in children with APN. However, this finding largely relies on a few studies of low methodological quality, i.e., high risk of selection bias, performance bias and attrition bias. Hence, high-quality and adequately powered RCTs are warranted.

Optical diagnosis of lower urinary tract infection: a pilot study in children

Conventionally, diagnosis of lower urinary tract infection (LUTI) is made on the basis of history, urine microscopy and culture. But there are limitations to this methodology especially in children and special populations where there is difficulty in obtaining a full history and details of clinical symptoms. The aim of this study was to determine if monitoring bladder wall oxygenation as a measure of bladder mucosal inflammation using transcutaneous near-infrared spectroscopy (NIRS) allows detection of the presence or absence of LUTI in children.

MATERIALS AND METHODS

A convenience sample of children referred to a pediatric urology clinic with an acute LUTI and a control group were studied. Diagnosis was confirmed by history, physical examination, laboratory investigations, and urine culture. Participants had transcutaneous measurement of an absolute measure of tissue oxygen saturation (TSI%) in their bladder wall, and a quadriceps muscle control site, using a spatially resolved (SR) wireless NIRS device. Average measures of bladder wall TSI% (B.TSI%) and quadriceps TSI% (Q.TSI%) and their differences (TSI.diff) were calculated and compared between those with LUTI and controls by performing a two-way repeated analysis of variance.

RESULTS

Thirty-four patients met the inclusion criteria (LUTI n = 12 and controls n = 22). Comparing LUTI to controls B.TSI% and TSI.diff values were significantly higher in the LUTI group (p < 0.0001), while Q.TSI% values were not significantly different.

CONCLUSIONS

Optical monitoring of bladder wall oxygenation is feasible in children. In this study a significant difference was evident in a SR NIRS-derived measure of absolute oxygen saturation in the bladder wall between children with UTI diagnosed by conventional testing methods, and those in a control group without infection. SR-NIRS monitoring of bladder wall oxygenation may offer a rapid and non-invasive means of bedside screening for LUTI where history and/or clinical signs are not available or adequate.

Could pyelonephritic scarring be prevented by anti-inflammatory treatment? An experimental model of acute pyelonephritis

Objectives. This study aimed to demonstrate if the addition of anti-inflammatory treatment to antibiotic therapy shows any superiority to the treatment with antibiotic only. Methods. Forty-nine Wistar rats were divided into 7 groups. Pyelonephritis was performed by E. coli injection to upper pole of kidneys except control group. Group 2 was not treated. Ceftriaxone, ketoprofen, “ceftriaxone + ketoprofen,” methylprednisolone, and “ceftriaxone + methylprednisolone” were given in the groups. The technetium-99m-dimercaptosuccinic acid scintigraphies were performed in 3rd day to detect pyelonephritis and 10th week to detect renal scarring. All kidneys were also histopathologically evaluated. Results. When 3rd day and 10th week scintigraphies were compared, initial 2.00 ± 0.30 point pyelonephritis score resulted in 0.71 ± 0.36 renal scar score in “ceftriaxone + ketoprofen” group (P = 0.039). Initial 2.00 ± 0.43 point pyelonephritis score resulted in 0.86 ± 0.26 renal scar score in “ceftriaxone + methylprednisolone” group (P = 0.041). Renal scar score was declined in “ceftriaxone + ketoprofen” group and “ceftriaxone + methylprednisolone” group compared with no-treatment group on 10th week of the study (P = 0.026, P = 0.044). On histopathological evaluation, it was seen that renal scar prevalence and expansion declined significantly in “ceftriaxone + ketoprofen and ceftriaxone + methylprednisolone” (P = 0.011, P = 0.023). Conclusion. It was evidenced that ceftriaxone treatment in combination with ketoprofen or methylprednisolone declined scar formation in scintigraphic and histopathologic examinations of the kidneys.

Protective effect of mitochondria-targeted antioxidants in an acute bacterial infection

Acute pyelonephritis is a potentially life-threatening infection of the upper urinary tract. Inflammatory response and the accompanying oxidative stress can contribute to kidney tissue damage, resulting in infection-induced intoxication that can become fatal in the absence of antibiotic therapy. Here, we show that pyelonephritis was associated with oxidative stress and renal cell death. Oxidative stress observed in pyelonephritic kidney was accompanied by a reduced level of mitochondrial B-cell lymphoma 2 (Bcl-2). Importantly, renal cell death and animal mortality were both alleviated by mitochondria-targeted antioxidant 10(6'-plastoquinonyl) decylrhodamine 19 (SkQR1). These findings suggest that pyelonephritis can be treated by reducing mitochondrial reactive oxygen species and thus by protecting mitochondrial integrity and lowering kidney damage.

The effect of vitamin E or vitamin A on the prevention of renal scarring in children with acute pyelonephritis

BACKGROUND

Numerous factors may contribute to renal tissue injury after urinary tract infection. We have evaluated the effects of vitamins A or E supplementation in combination with antibiotics for the prevention of renal scarring in acute pyelonephritis.

METHODS

A simple non-blind randomized clinical trial was conducted on 61 children aged 1 month to 10 years between 2004 and 2006. The inclusion criteria were positive urine culture, clinical findings, and 99mTc-dimercaptosuccinic acid (DMSA) scintigraphy-based evidence in favor of acute pyelonephritis. The children were randomized into three treatment groups: 10-day treatment with only antibiotics (control group; n = 25) and 10-day treatment with supplements of vitamin A (n = 17) or vitamin E (n = 18) in addition to antibiotics during the acute phase of infection. The final analysis was performed after excluding male patients. Each patient was evaluated twice by 99mTc-DMSA scintigraphy performed at least 6 months apart. P < 0.05 was considered to be statistically significant.

RESULTS

The analysis included 108 kidney units. The frequency of inflammation at the beginning of therapy was not significantly different in the three groups (63.3 % in vitamin A, 61 % in vitamin E, and 76.2 % in the control group). A worsening of lesions, based on the second 99mTc-DMSA scan, was observed in 42.5, 0, and 23.3 % of the control, vitamin E, and vitamin A patients, respectively (LR = 26.3, P < 0.001).

CONCLUSION

Vitamins A or E supplements were effective in reducing renal scarring secondary to acute pyelonephritis.

Can postpyelonephritic renal scarring be prevented?

Pyelonephritis in childhood may, in the worst cases, lead to long-term cardiovascular morbidity due to tubulointerstitial renal scarring. Renal damage is the end result of an interplay between (1) urinary tract anatomy and function, (2) bacterial virulence factors, and (3) the host innate immune system, which on the one hand manages bacterial clearance, but on the other causes tubulointerstitial inflammation, which underlies the renal scarring. It is unclear how common postpyelonephritic scarring is, and how many of the "scars" in fact represent congenital renal hypoplasia. We do, however, know that some situations have an increased risk for scars, i.e., large renal-uptake defects on initial renal scintigraphy or pyelonephritis in young girls with dilating vesicoureteral reflux. It seems logical that antiinflammatory or antioxidant therapy given concomitantly with antibiotics should lower the risk of postpyelonephritic scarring. Animal studies give some support to this idea, but research on humans has been surprisingly scant. In this issue of Pediatric Nephrology, we publish a study that indicates that antioxidant therapy with vitamin A or E given to children with pyelonephritis may indeed lower the risk for renal scarring. This is a track that needs to be pursued further.

Protective effects of bilirubin in an experimental rat model of pyelonephritis

OBJECTIVE

To investigate the effects of bilirubin in a rat model of pyelonephritis.

METHODS

Experimental pyelonephritis was induced in 32 wistar rats and 4 groups were formed: group 1 (no treatment), group 2 (antibiotic), group 3 (bilirubin), and group 4 (antibiotic + bilirubin). Antibiotic was given on days 3 to 8, and bilirubin was administered between days 0 and 8 of bacterial inoculation. Half of the rats were killed on the 9th day (early period) and histopathological parameters, immunohistochemical renal fibrosis markers, apoptosis, and oxidant/antioxidant system activities were evaluated. The rest of the rats were killed at the 6th week of the study and evaluated for histopathological parameters and renal fibrosis markers.

RESULTS

Inflammatory activity was significantly lower in rats treated with antibiotic + bilirubin vs no treatment group both in the early and late periods. In the late period, inflammatory cell intensity was lower in rats treated with bilirubin vs no treatment and the antibiotic + bilirubin groups. Interstitial fibrosis/tubular atrophy was lower in the antibiotic + bilirubin group vs the no treatment and antibiotic groups, and in bilirubin vs antibiotic group. Tissue inhibitor of metalloproteinase-1 expression was lower in the bilirubin vs antibiotic group. Terminal deoxynucleotidyl transferase mediated 2'-deoxyuridine, 5'-triphosphate nick end labeling(+) cells were significantly lower in bilirubin and antibiotic + bilirubin groups vs no treatment group. Malondialdehyde levels were significantly lower in the antibiotic + bilirubin vs the no treatment group and superoxide dismutase activity was significantly higher in the antibiotic and antibiotic + bilirubin groups vs the no treatment group.

CONCLUSION

Bilirubin may have protective effects on pyelonephritis-associated inflammation in both early and late periods in addition to fibrosis and apoptosis when applied with antibiotics. When used alone, bilirubin may also prevent inflammation (in the late period) and apoptosis.

The effect of vitamin A on renal damage following acute pyelonephritis in children

Animal studies suggest that administration of vitamin A to rats with experimental urinary tract infection decreases the frequency of renal scars (Kavukçu et al., BJU Int 83(9):1055-1059, 1999). The aim of this study was to determine the effect of vitamin A on the rate of permanent renal damage in children with acute pyelonephritis. Fifty children, median age of 24 months (range 2-144), with first-time pyelonephritis verified by an uptake defect on acute dimercaptosuccinic acid (DMSA) scan were included in the study and randomly allocated to the case or control groups. All were given intravenous ceftriaxone for 10 days followed by oral cephalexin for 3 months. Cases in addition were given a single intramuscular dose of vitamin A, 25,000 U for infants below 1 year of age and 50,000 U for older children. At the repeat DMSA scan after 3 months, five of 25 cases (20%) and 17 of 25 controls (68%) had abnormal findings (p = 0.001). In conclusion, administration of vitamin A was associated with a significantly lower rate of permanent renal damage.

Autografting of Renal Progenitor Cells Ameliorates Kidney Damage in Experimental Model of Pyelonephritis

Current therapies for pyelonephritic renal damage have severe limitations; stem cells may offer an exciting potential in regenerating nephrology. We aimed to investigate the feasibility of direct intrarenal injection of autologous renal progenitor cells (RPCs; originated from epithelial cells in Bowman's capsule) in chronic pyelonephritis rat model. Twenty-seven rats were divided into three groups. The control group (GI, n = 3) underwent sham subcapsular injection of isotonic saline. Pyelonephritis was induced in the right kidney of the remaining 24 rats and isotonic saline (GII, n = 12) or labeled autologous RPCs, obtained from a biopsy of left kidney (GIII, n = 12), were injected into the subcapsular space 6 weeks later. At 7, 14, 28, and 60 days, dimercaptosuccinic acid scan was performed in three animals of each group at every interval and subsequently renal sections were obtained for the evaluation of tubular and glomerular regeneration and proliferation. Cell transplantation resulted in the reduction of tubular and glomerular atrophy after 2 weeks. The transplanted cells were observed in the reconstructed region of the kidneys as evidenced by the presence of fluorescently labeled cells both in tubules and glomeruli. We also observed significant decrease in interstitial fibrosis in the fourth week and there were higher amount of Ki-67-positive cells in GIII. Notably, the right renal tissue integrity was significantly improved in this group and revealed normal cortical function on day 60. Transplanting RPCs showed the potential for partial augmentation of kidney structure and function in pyelonephritis. Cellular repair was seen predominantly in the proximal tubule, the major site of injury in pyelonephritis. Our findings may pave the way toward the future regeneration of renal scarring of pyelonephritis in children.

Evaluation of Effectiveness of Vitamins C and E on Prevention of Renal Scar due to Pyelonephritis in Rat

Aim was evaluation of the effects of cosupplementation of, vitamins E and C, in preventing renal scarring in acute pyelonephritis. Animals and Treatments. Sixty rats were used, bacteria was injected through kidney. The rats were arranged randomly in 3 groups of 20 rats each. Rats in groups 1 and 2 were given once-daily intraperitoneal injections of gentamicin for ten consecutive days, beginning on the third day after inoculation. In group 2, vitamins E and C cotreatment and in group 3, vitamins E and C cotreatment without gentamicin injection were started. Three rats in each group were killed 24 hours after the inoculation (for infection and inflammation document) and forty-eight hours after the antibiotic injection (for efficacy of treatment). After eight weeks, the rest of rats were killed, and kidneys evaluated for percent of scaring. Result. There was also significant difference of degree of scar formation (1.4 and 3.4% versus 8.6%, P = .001). The group which received gentamicin only had moderate to severe scaring, but the two groups which received vitamin C and vitamin E showed no or mild renal scaring. Conclusion. The study showed that administration of antioxidants can protect scaring due to pyelonephritis with or without antibiotic administration.

Renal tissue damage after experimental pyelonephritis: role of antioxidants and selective cyclooxygenase-2 inhibitors

OBJECTIVES

To investigate the involvement of oxidative stress in the pathogenesis of acute pyelonephritis, and to evaluate the impact of meloxicam and/or L-carnitine in addition to conventional antibiotic treatment.

METHODS

A total of 48 Wistar rats were divided into 4 groups according to their treatment, which was started 1 day after inoculation of all rats with Escherichia coli (ATCC 25 922, 10(10) cfu/mL). Group 1 received only antibiotic treatment with ceftriaxone (50 mg/kg, IM). Groups 2 and 3 received L-carnitine (500 mg/kg, IM) and meloxicam (3 mg/kg, IM) in addition to conventional treatment, respectively. Group 4 received combination therapy (L-carnitine and meloxicam) in addition to the first group. Rats were killed 3 and 7 days after E. coli inoculation and underwent nephrectomy. Histologic determination of tubular atrophy, acute and chronic inflammation, interstitial fibrosis and biochemical determination of superoxide dismutase and catalase activity, total thiol content, total antioxidant capacity, and malondialdehyde and protein hydroperoxide levels were measured.

RESULTS

Interstitial fibrosis (P = .06), chronic inflammation (P = .536), and tubular atrophy (P = 0.094) decreased in group 4 compared with the other groups, but there was a statistically significant decrease only in acute inflammation (P = .015). In addition, if the day of nephrectomy is considered, there was again a significant decrease in acute inflammation on day 7 compared with day 3 in groups 2, 3, and 4 (P = .002). Catalase significantly increased in group 2 (P = .029), group 3 (P = .02), and group 4 (P = .014), and decreased in group 1 (P = .012) in day 7.

CONCLUSIONS

L-carnitine and meloxicam alleviated oxidative stress, probably by decreasing lipid peroxidation and enforcing antioxidant defense system. Acute renal inflammatory injury can be prevented much more effectively by combination therapy rather than by conventional therapy alone.