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Biomedical subjects

S H Jacobson

Publications and source records attributed to S H Jacobson.

At least 19 recordsLinked to original sources
PubMed2007

Preserved leukocyte CD11b expression at the site of interstitial inflammation in patients with high-flux hemodiafiltration.

The impact of high-flux hemodialysis on clinical outcomes remains controversial. We have previously shown that in vivo transmigrated leukocytes from patients with low-flux bioincompatible hemodialysis have an impaired capacity to upregulate CD11b at the site of interstitial inflammation. In the present study, we investigated the in vivo capacity of transmigrated monocytes and granulocytes to express CD11b at the site of interstitial inflammation in 10 patients on biocompatible high-flux hemodiafiltration or high-flux hemodialysis and 12 healthy subjects, and the in vitro response to a bacteria-related peptide (N-formyl-methionyl-leucyl-phenylalanine (fMLP)). Leukocyte formation of hydrogen peroxide (H(2)O(2)) and leukocyte apoptosis were also studied. In patients, both monocytes and granulocytes had a preserved capacity to express CD11b following in vivo transmigration to sites of interstitial inflammation, compared with cells from healthy subjects. Furthermore, monocytes and granulocytes from patients showed a preserved ability to respond to challenge with fMLP in the extravascular milieu. The intracellular killing capacity of leukocytes (H(2)O(2) production) in the interstitium was similar as of cells from healthy subjects both before and after stimulation with fMLP. Following maximal receptor independent stimulation (phorbol 12-myristate 13-acetate), leukocytes from patients showed lower H(2)O(2) production at the site of intense inflammation, compared with cells from healthy subjects. Finally, leukocyte apoptosis in interstitial inflammation was similar in patients and healthy subjects. We conclude that in vivo transmigrated leukocytes from patients on biocompatible high-flux hemodiafiltration or high-flux hemodialysis have a preserved capacity to express CD11b at the site of interstitial inflammation. This may have important biological implications.

Adult↗
PubMed2005

Neutrophil activation in anti-proteinase 3-positive vasculitis--a prospective study.

In vitro studies have demonstrated that antineutrophil cytoplasmic antibodies (ANCA) have the capacity to activate neutrophils. Whether circulating neutrophils in patients with vasculitis are activated is under debate. Eight consecutive patients with antiproteinase 3 (PR3) positive acute vasculitis were included in this prospective study. Neutrophil expression of adhesion molecules, Fc-receptors and the ANCA-antigen PR3 was analysed and clinical characteristics were documented at inclusion and after 1, 3, 6 and 9 months in the same individuals. As additional markers of inflammation and endothelial activation interleukin-8 and soluble vascular cell adhesion molecule-1 in serum were analysed at the same time points. The expression of adhesion molecules on circulating neutrophils, CD62L and CD11b after in vitro N-formyl-methionyl-leucyl-phenylalanine stimulation was significantly decreased at diagnosis and after 1 month but returned to normal levels after 3-9 months. The neutrophil expression of Fc-receptor IIIb (CD 16) was decreased at diagnosis but normalized after 1-9 months. The main finding was an activated neutrophil adhesion phenotype at diagnosis and after 1 month, with normalized expression of adhesion molecules at 3-9 months. A pathological regulation of adhesion molecules may have implications on the endothelial damage seen in vasculitis.

Antibodies, Antineutrophil Cytoplasmic↗
PubMed2004

IGFBP-1 levels in adult women born small for gestational age suggest insulin resistance in spite of normal BMI.

OBJECTIVE: Impaired fetal development may contribute to decreased insulin sensitivity. This study was designed to characterize serum markers of insulin resistance in adults born small for date or born prematurely. STUDY DESIGN: Fifty subjects, all women, were evaluated at a mean age +/- SD of 26 +/- 2 years (range: 23-30 years). They were allocated to three groups: (i) born fullterm with birth weight <2600 g (n = 18) (small for gestational age, SGA), (ii) born before gestational week 32 (n = 15) (ex-preterm), and (iii) controls, born fullterm with appropriate birth weight (n = 17). Anthropometric data as well as fasting serum samples of plasma B-glucose, serum lipids, insulin, insulin-like growth factor-I (IGF-I) and insulin-like growth factor binding protein-1 (IGFBP-1) levels were determined. RESULTS: In the SGA group final height was lower and they weighed less compared with the controls. Fasting insulin and glucose levels did not differ amongst the groups. Triglycerides were lower in the SGA group and in the ex-preterm group compared with the controls (P < 0.05). The SGA group showed lower IGFBP-1 levels compared with the controls median 17 (range 3-121) vs. 26 (7-67) microg L-1; P < 0.05]. The IGF-I levels in the SGA, ex-preterm and control groups were 212 +/- 58, 259 +/- 37 and 216 +/- 32 microg L-1, respectively, corresponding to a mean SD score of -0.8 +/- 1.0, 0.1 +/- 0.6 and -0.6 +/- 0.6. CONCLUSION: As IGFBP-1 is a marker of insulin sensitivity, the low levels observed in adult women with normal BMI, born small for date, suggest relative insulin resistance in spite of normal BMI.

Adult↗
PubMed2004

Biopsy-verified response of severe lupus nephritis to treatment with rituximab (anti-CD20 monoclonal antibody) plus cyclophosphamide after biopsy-documented failure to respond to cyclophosphamide alone.

BACKGROUND: The monoclonal anti-B cell antibody rituximab (Rituxin, Mabthera) may be of benefit in antibody-driven diseases, including systemic lupus erythematosus (SLE) nephritis. PATIENTS AND TREATMENT: Two female patients with biopsy-confirmed severe and active SLE nephritis despite treatment with cyclophosphamide (CyX) were given four rituximab infusions plus two additional CyX infusions. RESULTS: Both patients tolerated the treatment well and SLE activity improved. On repeat kidney biopsy after the combined treatment, Patient 1 showed a profound reduction of nephritis activity, and she was maintained on low-dose prednisolone only. A repeat biopsy after 1 year confirmed the sustained reduction of lupus nephritis activity. In Patient 2, rebiopsy after combined treatment also showed a significant reduction in disease activity. CONCLUSION: These cases provide histopathological documentation of a significant treatment benefit from rituximab plus CyX in two patients refractory to CyX alone. This combination is being explored further as salvage therapy for such CyX-resistant patients.

Adult↗
PubMed2003

Antineutrophil cytoplasmic antibodies induce decreased CD62L expression and enhanced metabolic activity in monocytes.

Monocyte in vitro activation by antimyeloperoxidase (anti-MPO)- and antiproteinase-3 (anti-PR3)-positive sera, corresponding immunoglobulin G (IgG) fractions and monoclonal antibodies against MPO and PR3 was evaluated. The expression of adhesion molecules, l-selectin (CD62L) and CR3 (CD11b), involved in leucocyte endothelial adhesion, and metabolic activity, measured as the production of hydrogen peroxide, were analysed. Decreased expression of CD62L was demonstrated in monocytes after incubation with antineutrophil cytoplasmic antibody (ANCA)-positive sera. This finding was not accompanied by changes in CD11b expression. Metabolic activity was increased in monocytes after incubation with ANCA-positive IgG fractions as well as after incubation with monoclonal anti-MPO and anti-PR3. These findings support the concept that the pathophysiological effect of ANCA is partly mediated through the action on crucial events in monocyte activation, such as CD62L downregulation and oxygen radical production.

Adolescent↗
PubMed2003

Haemostatic complications in haemodialysis patients: effect of type of vascular access and dialysis filter.

Impaired haemostasis is common in patients with end-stage renal disease, and may cause either thrombotic or bleeding complications. The purpose of this study was to assess whether plasma markers of coagulation activation in patients undergoing chronic haemodialysis (HD) can identify high-risk individuals, and to test the relevancy of type of vascular access or dialysis filter. We measured plasma levels of prothrombin fragment 1+2, fibrin D-dimers and tissue factor in 82 HD patients before and after dialysis. Clinical endpoints during the year following blood sampling were thrombosis in blood access, changes in blood access, other thromboembolic events, bleeding complications, ischaemic vascular disease, or death. We found elevated baseline levels of all three parameters in HD patients, compared to normal reference ranges. Plasma levels of all parameters (particularly fibrin D-dimers) were significantly higher in patients with prosthetic grafts and central venous dialysis catheters than in patients with native vessels. Patients with AV-fistulas or grafts who had bleeding complications (n=7) had significantly higher plasma levels of fibrin D-dimer and prothrombin fragment 1+2. Bleeding complications also occurred more frequently among the patients with prosthetic grafts (3/18) or central venous dialysis catheters (3/11) compared with those with grafts from native vessels (1/53). Other than a bleeding tendency, our data do no show any correlation between coagulation parameters and other clinical complications during haemodialysis. In conclusion, we found elevated plasma levels of markers of coagulation activation among HD patients. High levels of D-dimers and prothrombin fragment 1+2 correlated to bleeding diathesis instead of thromboembolism, and this tendency was most pronounced in patients with prosthetic grafts.

Aged↗
PubMed2001

Increased expression of CD25 and HLA-DR on lymphocytes recruited into the peritoneal cavity in non-infected CAPD patients.

The impact of uremia per se, peritoneal dialysis (PD) and hemodialysis (HD) treatment was evaluated on characteristics of lymphocytes. CD4, CD8, CD25 and HLA-DR were analyzed, with flow cytometry, in lymphocytes prepared from peripheral blood of uremic (n = 10) and hemodialysis patients (n = 10). Peritoneal dialysate was also obtained from patients on CAPD (n = 12). A decreased relative and absolute lymphocyte count was observed in peripheral blood from uremic, HD and CAPD patients compared to healthy controls (p < 0.03, p < 0.03 and p < 0.02, respectively). On the other hand, the relative distribution of lymphocytes was significantly higher in peritoneal dialysate compared to peripheral blood of CAPD patients (p < 0.02). Likewise, the absolute CD4 positive lymphocyte count was lower in the peripheral blood from uremic. HD and CAPD patients as compared to healthy controls (p < 0.001, respectively). In CAPD patients the relative distribution of CD4 positive cells (p < 0.001) was lower, while quantitative CD25 level (p < 0.01) and the relative count of HLA-DR (p < 0.0001) was increased in the peritoneal dialysate compared to blood. Taken together a selective activation of lymphocytes in peritoneal dialysate as compared to peripheral blood from uremic, HD and CAPD patients was observed. The altered biological function of the inflammatory cells may therefore explain the increased susceptibility to infectious diseases.

Adult↗
PubMed2001

Escherichia coli-induced expression of IL-1 alpha, IL-1 beta, IL-6 and IL-8 in normal human renal tubular epithelial cells.

The aim of the present study was to investigate whether the IL-1 family cytokines, in addition to IL-6 and IL-8, could be induced in normal human cortical epithelial cells in response to bacterial stimuli. Human renal tissue was obtained from 9 patients undergoing elective tumour nephrectomy. Renal cortical epithelial cells of tubular origin were prepared from the unaffected tissue. The proximal tubular cells were stimulated for 2, 6 and 24 h with a heat-inactivated pyelonephritogenic Escherichia coli strain DS-17. Cultured unstimulated tubular cells served as controls. IL-1 alpha, IL-1 beta, IL-1 receptor antagonist, IL-6, IL-8, IL-10, TNF-alpha, G-CSF and GM-CSF were analysed using immunohistochemistry at the single cell level. The nonstimulated cells were found to express low levels of IL-6 and IL-8 (mean value < 3% of total cells). In contrast, E. coli exposure resulted in significantly increased incidences of IL-6 and IL-8 expressing cells (mean values approximately 18% of total cells) peaking within two hours of stimulation (P < 0.008 and P < 0.02 versus non-stimulated cells, respectively). A gradual decrease was thereafter observed at 6 and 24 h, respectively, although persistently higher compared to controls. A different kinetic response was found for IL-1 alpha, IL-1 beta and IL-1 receptor antagonist-expressing cells, which peaked 24 h after E. coli stimulation (mean values 3--10%) (P < 0.008, P < 0.02, P < 0.02 versus non-stimulated cells, respectively). Low levels of TNF-alpha and GM-CSF were found in 3 of the 9 donated epithelial cells, peaking at 2 h, and IL-10 and G-CSF producing cells in 1 patient each. In conclusion we found that heat-inactivated pyelonephritic E. coli induced a proinflammatory cytokine response in the normal human proximal tubular cells including the IL-1 family, IL-6 and IL-8.

Adult↗
PubMed2001

Effects of C-peptide on glomerular and renal size and renal function in diabetic rats.

BACKGROUND: Strict glycemic control and antihypertensive treatment may decrease but not eliminate the risk of progressive nephropathy in diabetic patients. C-peptide has been shown to exert beneficial effects on complications, including incipient nephropathy, in type 1 diabetes. METHODS: Renal effects of 14 days of intravenous infusion of C-peptide or NaCl (placebo) were studied in three groups of rats: one nondiabetic NaCl-treated (normal, N = 7), one streptozotocin diabetic NaCl-treated (D-placebo, N = 7), and one streptozotocin diabetic C-peptide-treated group (D-C-p, N = 7). Metabolic data and albuminuria were measured in metabolic cages every fourth day. After 14 days, the glomerular filtration rate (GFR) was measured by inulin clearance and available renal functional reserve (RFR) by glycine infusion, whereupon one kidney was perfusion fixed for morphological studies. RESULTS: Glucose levels were 36.7 +/- 1.3 and 34.0 +/- 1.7 mmol/L in the D-placebo and D-C-p groups, respectively. The D-placebo group presented a 32% (P < 0.001) larger glomerular volume than the D-C-p group. The D-placebo group also presented a significantly larger renal weight than the normal group in contrast to the D-C-p group. Urinary albumin excretion increased in the D-placebo group in contrast to the other groups. GFR was 1.72 +/- 0.12 mL/min (normal), 3.73 +/- 0.19 mL/min (D-placebo, P < 0.001 vs. normal) and 2.16 +/- 0.16 mL/min (D-C-p, nonsignificant vs. normal). Available RFR was 93 +/- 25% (normal), 10 +/- 4% (D-placebo, P < 0.05 vs. normal) and 57 +/- 13% (D-C-p, nonsignificant vs. normal) of basal GFR. CONCLUSIONS: Physiological doses of homologous C-peptide prevent the development of glomerular hypertrophy, albuminuria, and glomerular hyperfiltration in rats with experimentally induced diabetes.

Albuminuria↗
PubMed2001

"Reverse engineering" a formulary selection algorithm to determine the economic value of pentavalent and hexavalent combination vaccines.

INTRODUCTION: Combination vaccines with overlapping, noncomplementary components are being introduced to reduce the number of separate injections required to immunize children. A vaccine selection algorithm using operations research techniques was developed as a tool for vaccine purchasers to assemble formularies of monovalent and combination vaccines that would satisfy the recommended immunization schedule. The algorithm weighs distinguishing features of economic consequence among competing vaccines to achieve the lowest overall cost to payers and/or to society for immunization. This method was adapted here to solve for the purchase price of several hypothetical future pentavalent and hexavalent combination vaccines that would permit each to "win" a place in such a lowest cost formulary. METHODS: Integer programming and an iterative bisection search method determined the maximum "inclusion price" of 4 vaccines not licensed in the United States as of September, 2001 [diphtheria-tetanus-acellular pertussis (DTPa)-Haemophilus influenzae type b (HIB)-hepatitis B (HBV), DTPa-HIB-inactivated polio vaccine (IPV), DTPa-HBV-IPV and DTPa-HIB-HBV-IPV], in competition with 15 existing formulations of licensed vaccines for these diseases at their March, 2000, federal contract discount prices. Both 5-visit and 6-visit scenarios were studied. Different preparation costs were assigned to lyophilized powder ($1.50), liquid ($0.75) and prefilled-syringe ($0.25) formulations/packaging. Injection costs were varied stepwise from $5 through $45 for each dose administered, shifting from a payer's to a societal perspective. RESULTS: Overall inclusion prices (maximum price for each candidate vaccine to be included in a lowest cost formulary) ranged from $9 to $129 per dose depending on cost assumptions and usage frequency (values would be higher if competing against private-sector vaccine prices). The range was $27 to $68 per dose for DTPa-HIB-HBV, at optimal utilization to avoid extra vaccination. Similarly, as injection costs varied from $5 to $45, DTPa-HIB-IPV ranged from $28 to $75. With the same assumptions, DTPa-HBV-IPV would earn a place in a best value formulary at prices from $35 to $76. As expected the inclusion prices for hexavalent DTPa-HIB-HBV-IPV, $40 to $123, were higher (reflecting more economic value) than for pentavalents. When the assumed injection costs rose to > or = $8, the more expensive HIB-HBV and DTPa-HIB tended to appear in lowest cost formularies, because their cost premium over separate monovalent and trivalent products was outweighed by the savings from one fewer injection. CONCLUSION: Reverse engineering the vaccine selection algorithm provides a tool to demonstrate the economic value of new combination vaccines and to make pricing decisions.

Algorithms↗
PubMed2000

Increased blood pressure but normal renal function in adult women born preterm.

UNLABELLED: It has been suggested that children born small for gestational age may develop hypertension and renal dysfunction in adulthood due to impaired fetal kidney development. Very little information on this issue is available on children born preterm. The objective of this study was to investigate the relationship between birth weight, blood pressure, and kidney function in adult subjects who were born preterm or born small for gestational age (SGA). STUDY DESIGN: Subjects (n = 50), all women born between 1966 and 1974, were evaluated at a mean age of 26 +/- 1.9 years. They were allocated to three groups: (1) born before gestational week 32 (n = 15), (2) born full term with birth weight < 2600 g (n = 18) (SGA), and (3) controls, born full term with appropriate birth weight (n = 17). Casual blood pressure, ambulatory 24-h blood pressure (ABPM), glomerular filtration rate (GFR), renal plasma flow (ERPF) and urinary albumin excretion were determined. RESULTS: Preterms had significantly higher casual systolic and mean arterial blood pressure levels compared to controls (123 +/- 13 vs 110 +/- 7 mmHg, P < 0.01, and 87 +/- 9 vs 79 +/- 6 mmHg, P < 0.005, respectively). ABPM was not significantly different between the groups. When the number of systolic recordings > 130 mmHg/subject during ABPM was calculated, the preterms had significantly more recordings above this value (P < 0.05) as well as a significantly increased area under the curve > 130 mmHg and > 140 mmHg systolic (P < 0.05) compared to the controls. SGA subjects were not significantly different from controls. There were no significant differences in GFR, ERPF or urinary albumin excretion between the three groups. CONCLUSION: Women born preterm seem to have a disturbance in blood pressure regulation in adulthood, a finding that is not observed for those born small for gestational age. Kidney function in early adulthood seems to be normal in subjects born preterm or small for gestational age.

Adult↗
PubMed2000

Impaired monocyte CD11b expression in interstitial inflammation in hemodialysis patients.

BACKGROUND: It is not known to what extent intravascular phenotypic alterations in adhesion molecule expression induced by hemodialysis influence the recruitment of monocytes and their ability to up-regulate CD11b at the local site of inflammation in the interstitium. Using a skin suction chamber technique, we addressed these issues in eight hemodialysis patients and in eight healthy subjects. METHODS: Two skin blisters were raised on the forearm of each individual and blister exudate collected. The blisters were then stimulated with autologous serum (active blister, intense inflammation) or buffer (control blister, intermediate inflammation), respectively. Thereafter the patients were treated with Cuprophan hemodialysis for four hours. After 10 hours, the exudate was aspirated from each chamber in all subjects. Monocyte count and expression of CD11b were analyzed in serum and blister fluid by flow cytometry. Then, monocytes from healthy blood donors were incubated in blister fluid from patients and healthy subjects in order to determine the local chemotactic activity in terms of CD11b up-regulation. Monocyte chemotactic protein-1 (MCP-1), a marker of systemic monocyte chemotactic activity, was also analyzed in serum at 0 and 10 hours in all individuals. RESULTS: The number of monocytes at the site of inflammation in the interstitium in hemodialysis patients correlated with the expression of CD11b on transmigrated cells (r = 0.78, P < 0.001). Monocytes collected in the active blister fluid of dialysis patients expressed equal levels of CD11b as cells collected from healthy subjects. By contrast, monocytes collected from the control blisters of patients expressed lower levels of CD11b than cells from healthy subjects (P < 0.01), despite equal interstitial biological activity of CD11b-mobilizing factors in blister fluid from patients and healthy subjects and the fact that patients had higher systemic chemotactic activity in terms of MCP-1 concentration in serum (P < 0.001). CONCLUSION: Monocytes from hemodialysis patients have the capacity to mobilize CD11b to the same extent as cells from healthy individuals at the inflammatory spot, but more intense stimuli are required for such actions, probably because of a transient refractoriness.

Adult↗
PubMed2000

Three monocyte-related determinants of atherosclerosis in haemodialysis.

BACKGROUND: It has been suggested that monocyte-related inflammatory mediators play a role in atherosclerosis. Haemodialysis induces phenotypic changes in adhesion molecule expression on monocytes. Soluble vascular cell adhesion molecule-1 (sVCAM-1), an adhesion molecule involved in monocyte recruitment, has been proposed to correlate with the extent of atherosclerosis in humans. Monocyte chemotactic protein-1 (MCP-1) functions as a monocyte-specific chemoattractant. METHODS: We studied monocyte count, CD11b/CD18 expression on monocytes, MCP-1, and sVCAM-1 in nine patients on either cuprophane or polysulphone haemodialysis (n=18 treatments) at times 0 (before haemodialysis), 3 h (end of haemodialysis), 4, 6, 8 and 24 h after start of treatment, as well as in 18 healthy subjects. RESULTS: Monocyte CD11b/CD18 expression increased with both membranes (P:<0.001) during and after dialysis compared to before treatment. The concentrations of sVCAM-1 and MCP-1 were higher in patients compared to those in controls both before, during and after haemodialysis (P:<0.001 at all time points). There were correlations between the expression of CD11b/CD18 on monocytes and the interdialytic concentrations of sVCAM-1 (r=0.76, P:<0.001) and MCP-1 (r=0.54, P:<0.05) and between MCP-1 and sVCAM-1 before and after haemodialysis (P:<0.05). CONCLUSION: Patients on haemodialysis have an increased systemic chemotactic activity for monocytes, unphysiological phenotypic alterations in CD11b/ CD18 expression during and after dialysis, and increased sVCAM-1 and MCP-1 concentrations. Prospective studies are needed to establish the role of these abnormalities in the pathogenesis of atherosclerosis in haemodialysis patients.

Adult↗
PubMed1999

An integer programming model for vaccine procurement and delivery for childhood immunization: a pilot study.

The National Immunization Program of the Centers for Disease Control and Prevention has identified several challenges that must be faced in childhood immunization programs to deliver and procure vaccines to protect against the common preventable diseases. The biomedical challenge is how to combine and formulate products to take advantage of new vaccines without requiring additional injections. A programmatic challenge is to incorporate then into already crowded immunization schedules. The economic challenge is to make wise procurement choices from among a growing number of competing products. This paper reports the results of a pilot study using operations research methodologies to address the third of these challenges. The pilot is an integer programming model for procuring vaccines for a set of childhood diseases. The model is studied under various scenarios (minimum total cost, next lowest total cost, maximum total cost, minimum total cost with all manufacturers represented). The results of this pilot study demonstrate how a practical set of operations research tools can be developed to guide vaccine selection and procurement, which might stimulate the development of innovations in new vaccines to meet the challenges of disease control through immunization.

Centers for Disease Control and Prevention, U.S.↗
PubMed1999

Vesico-ureteric reflux: occurrence and long-term risks.

The prevalence of vesico-ureteric reflux in the general population is unknown, but it is increased in risk groups, such as children with symptomatic urinary tract infection, schoolgirls with asymptomatic bacteriuria, first-degree relatives of patients with reflux and children with prenatal dilatation of their upper urinary tract. Children and adults with pyelonephritic renal scarring are at risk of serious long-term complications, e.g. hypertension and renal failure. Modern paediatric care, with early detection and treatment of urinary tract infections and reflux during childhood and adolescence, may improve long-term prognosis. In the adult patient with established pyelonephritic renal scarring, careful control of hypertension may retard the rate of progression, and angiotensin converting enzyme inhibitors may have renal protective properties.

Adolescent↗
PubMed1999

Vesico-ureteric reflux and other risk factors for renal damage: identification of high- and low-risk children.

This article reviews the literature with respect to various risk factors for permanent renal damage in children with urinary tract infection. Vesico-ureteric reflux is an important risk factor, but renal damage can occur in the absence of reflux. Renal damage does not always occur in the presence of gross reflux. Renal scars always develop at the same site as a previous infection in the kidney. Recurrent pyelonephritis and delay in therapy increase the likelihood of renal damage, although it is not known how long a delay is dangerous to the human kidney. Recent studies using 99mtechnetium-dimercaptosuccinic acid (DMSA) scintigraphy have not confirmed the findings of previous studies showing that children below 1 y of age are more vulnerable to renal damage. It is more likely that all children run the risk of renal scarring in cases of acute pyelonephritis. The role of bladder pressure is still not entirely understood. Therefore more studies are needed in order to determine the relationship between high voiding pressures in some, otherwise healthy, children with urinary tract infection and renal scarring. The importance of bacterial virulence in the development of renal scarring is unclear. DMSA scintigraphy and voiding cystourethrography are the most reliable tools for identifying children at risk of renal scarring. As a single method DMSA scintigraphy appears to be better than voiding cystourethrography.

Age Factors↗