Long-term followup of 158 young adults surgically treated for vesicoureteral reflux in childhood: the ongoing risk of urinary tract infections.

PURPOSE: We recorded urinary tract infections in the long term after surgical reflux correction. MATERIALS AND METHODS: A total of 158 of 189 patients (160 females and 29 males) who were followed in 1985, an average of 10.8 years after reflux surgery were contacted again in 1995. At that time median patient age was 26 years (range 15.7 to 38.8) and the average period of observation was 20.3 years (range 13.4 to 26). RESULTS: In 82% of the patients febrile and in 18% afebrile symptomatic urinary tract infections had developed preoperatively. In the first 10-year period after operation 46% of patients continued to have symptomatic urinary tract infections compared with 52% in the second 10-year interval. In the 2 periods the incidence of febrile urinary tract infection was about 17%. In the whole postoperative observation period symptomatic urinary tract infections developed in 66% of all patients, including 74% of female patients. Symptomatic urinary tract infections were observed during 8 of 46 pregnancies (17%). CONCLUSIONS: After successful surgical reflux correction susceptibility to urinary tract infection continues for a number of years in many girls and women. However, postoperatively urinary tract infections are primarily afebrile.

[Pre- and postpartum ultrasound examinations for diagnosis of urogenital abnormalities]. / Prä- und postpartale Ultraschalluntersuchungen zur Diagnostik von Urogenitalfehlbildungen.

BACKGROUND: The aim of the study was to evaluate prenatal and postpartal sonographic investigations to diagnose congenital uropathies. PATIENTS/METHODS: The Mainz birth defect monitoring system, the "Mainzer Model", was launched in 1990. Over a period of five years (1/90 to 1/95) 19,028 newborns underwent postpartal sonographic examination. Anamnestic data including prepartal sonographic examination were collected. According to a defined ultrasound criteria list, ultrasound findings were considered normal in 94.8% of the neonates, 4.4% were defined as requiring a follow-up examination and 0.8% were pathological. In the current study we analyzed patients with pathological findings with their pre- and postpartal sonographic investigations as well as their clinical data (urinary tract infections, operative procedures). RESULTS: In the study group prenatal ultrasonography showed evidence of severe anomalies only in 51 fetuses (32.9%). Surgical correction was required in 39 cases. 20 (51%) have been diagnosed prenatally. 28 patients presented with urinary tract infections. Out of this group only 11 patients have been detected by prenatal ultrasound. CONCLUSION: In conclusion, postnatal ultrasound is more effective to diagnose anomalies of the urinary tract. To prevent complications i.e. urinary tract infections a neonatal screening program would be valuable.

The interaction of buccal mucosal epithelial cells with E. coli bacteria enhances the intraepithelial calcium flux and the release of prostaglandin E2 (PgE2).

Mucosal epithelial cells contribute significantly to host defense mechanisms. Uroepithelial cells (UEC) from healthy donors suppress bacterial growth in vitro. Bacterial adherence to UEC has been shown to be a prerequisite. Similar results have been shown for buccal epithelial cells (BEC). The host response triggered by the host-parasite interaction seems to involve signal transduction and intracellular activation of second messengers. In this study the intraepithelial calcium flux was analyzed in individual BEC after bacterial contact. BEC were derived from scrapes of the buccal mucosa and labelled with fluo-3 (a calcium indicator). Thereafter the cells were analyzed immediately with a FACscan flowcytometer. The intracellular events were evaluated before and after the addition of viable E. coli bacteria (strain 4389, K1O1H7, pili II pos.). For control, the influence of prostaglandins, histamine, PMA, LPS and opsonized avital E. coli on the epithelial calcium flux was investigated. Additionally, supernatants of BEC-E. coli cocultures were analyzed with respect to their PgE2 content. PgE2 concentrations in supernatants of BEC, cultured alone or together with E. coli, were measured by a commercial PgE2 ELISA kit. The addition of vital E. coli to BEC was promptly answered by a significant intracellular calcium flux. PgE2, histamine and PMA, but not PgF2alpha, PgE1, LPS and opsonized E. coli, increased intracellular calcium. BEC alone did not release PgE2. After coculture with E. coli increased levels of PgE2 were measured in the supernatants. PgE2 release was still enhanced by coactivation of the BEC with phorbolester (PMA). Our results confirm that calcium flux in mucosal epithelial cells is stimulated by the cell-bacteria contact. We suggest that the increased PgE2 release amplifies the stimulation of intraepithelial second messengers. The resulting cell activation may lead to the secretion of antimicrobial peptides, thereby contributing to the regulation of mucosal host resistance to bacterial infections.

[Granulocyte function in premature infants before the 34th week of pregnancy and in mature newborn infants]. / Granulozytenfunktion bei Frühgeborenen ab der 34. Schwangerschaftswoche und bei reifen Neugeborenen.

BACKGROUND: Preterm and term neonates have an increased risk to develop severe bacterial infections. Impairment of neutrophil function may be responsible for this increased risk. Other diseases related to prematurity like retinopathia of prematurity (ROP) or broncho-pulmonary dysplasia (BPD) on the other hand may be due to poorly controlled O2-radical production. PATIENTS AND METHODS: Blood samples of 112 premature (34 weeks of gestation and older) and term neonates were analysed. Blood samples of 23 healthy adults (18 to 50 years old) served as controls. O2-radical production and phagocytosis of neutrophils were determined by flow cytometry, using a commercial test system. RESULTS: Under the experimental conditions applied, the capacity to produce O2-radicals following vigorous stimulation (E. coli) is comparable between neutrophils of preterm/term neonates and healthy adults. However, unstimulated or weakly stimulated (fMLP) neutrophils of preterm and term neonates show a statistically higher O2-radical production as neutrophils of the control group. The production of oxygen radicals increases during the first 10 days of the life. The capability of neutrophils to phagocytose E. coli is significantly lower in newborns (preterm and term) compared to the adult controls. CONCLUSIONS: The values reported here for phagocytosis and O2-radical production utilizing a commercially available test system may serve as "preliminary normal values" for neonates. No differences were found between the groups of neonates with and without infection. Impaired neutrophil-phagocytosis possibly contributes to the increased risk of preterm and term neonates to acquire bacterial infections. The increased spontaneous O2-radical production, on the other hand, may play a role for the development of so called "free radical diseases" such as ROP or BPD. However, our results cannot add further proof to this hypothesis.

Host defense within the urinary tract. I. Bacterial adhesion initiates an uroepithelial defense mechanism.

Uroepithelial defense has ben suggested to contribute to the local host resistance against ascending urinary tract infection. The cellular mechanism, however, is not known. In this study, bacterial growth was measured under the direct and indirect influence of uroepithelial cells. To study if a specific ligand-receptor interaction is required for uroepithelial cell (UEC) activation, isogenic Escherichia coli mutants expressing either mannose-sensitive, mannose-resistant (p), or mannose resistant (s) pili were tested for their capacity to induce the UEC defense mechanism. The antibacterial effect of UEC was abolished either by performing coculture in chambers with a fluid-permeable membrane which separates UEC from bacteria or by inhibiting membrane contact using the antiadherence factor pentosane polysulfate. No difference between the various types of pili could be shown. All E. coli strains adhered comparably to the UEC and were subsequently suppressed in their growth. Even a "naked" mutant without expression of common pili showed a similar behavior. In conclusion, bacterial growth suppression depends on direct contact between the UEC and bacteria, but is independent of common pili expressed on E. coli.

Host defense within the urinary tract. II. Signal transducing events activate the uroepithelial defense.

It has been shown previously that the interaction between uroepithelial cells (UEC) from healthy donors and adherent. Escherichia coli suppresses bacterial growth in vitro. The following study was performed to investigate the nature of membrane signal transduction mechanisms involved in this process. UEC/E. coli cocultures were established in the presence of substances known to modulate transmembranous signals. Inhibition of calcium flux, either by calcium channel-blocking substances or by a calmodulin antagonist, depressed the antibacterial UEC function of "healthy" UEC. In contrast, receptor/ligand-induced stimulation of G-proteins, activation of the adenylate cyclase, and the increase of intracellular cyclic AMP levels by cytoplasmatic phosphodiesterase did not increase the antibacterial capacity of healthy UEC. However, the antibacterial function of defense-deficient UEC from patients with recurrent idiopathic urinary tract infection could be reconstituted by this treatment to almost normal levels. In conclusion, the antibacterial UEC defense function is activated by transmembranous signals from bacteria attached to the host cell surface. Activation involves the adenylate cyclase pathway. Activation of the phosphoinositol pathway may contribute to intracellular calcium fluxes.

Distribution of lymphocyte surface antigens in healthy neonates.

Using flow cytometric analysis we investigated the distribution of major lymphocyte surface antigens in newborn infants. A total of 221 newborns entered the study, of whom 53 fulfilled our criteria of healthy mature neonates. Percentages of immunofluorescent-positive cells were as follows (median and range from 25th to 75th percentiles given): for CD1 3.8%; 2.3%-5.8%. CD2 60.9%; 52.4%-66.8%. CD3 57.5%; 50.5%-63.3%. TcRass 57.7%; 48.1%-60.0%. CD4 36.3%; 28.0%-42.6%. CD8 23.0%; 20.0%-27.4%. CD11a 56.3%; 46.3%-68.5%. CD19 12.1%; 8.6%-14.8%. CD20 10.9%; 8.4%-12.9%. CD25 2.6%; 2.1%-4.5%. CDw52 61.0%; 51.2%-76.1%. CD71 5.2%; 3.1%-9.3%. While the ranges for the percentage of immunofluorescent-positive cells were rather small, there was a wide variation in the absolute numbers of marker immunofluorescent-positive cells.

[What is the cause of recurrent urinary tract infection?]. / Was sind die Ursachen der rezidivierenden Harnweginfektionen?

The increased susceptibility of patients prone to recurrent urinary tract infection (UTI) has been explained by an imbalance of bacterial virulence properties versus host defense capacities. In fact, the presence of certain virulence factors of the invading gram-negative bacteria (i.e. O-antigens, K-antigens, flagellae, hemolysine production, siderophores and fimbriae) determines the severity of clinical symptoms--whether UTI will present as a severe pyelonephritis or merely as an asymptomatic bacteriuria. On the other hand, an increased periurethral bacterial colonization, a deficiency of the uromucoid defense line, the increased density of globoseries glycolipids on uroepithelial cells, that function as receptors for type II mannose-resistant bacterial fimbriae and the defense defect of the uroepithelium itself contribute to the assumption that a localized defense deficiency within the non-obstructed urinary tract promotes the generalized susceptibility to recurrent UTI.

Progressive calcifications of lung and liver in neonatal herpes simplex virus infection.

We report a female neonate who developed severe septicemia presenting with pneumonia and hepatitis due to an infection with herpes simplex virus type II. In spite of antiviral as well as intensive care therapy, three weeks after admission, extensive hepatic calcification was demonstrable on abdominal radiograph, a sign of severe cellular necrosis. In contrast the pulmonary infiltration recovered completely. The clinical follow up was completed by ultrasound and radiography. The infant died at the age of two months secondary to severe postnecrotic hepatic failure. At autopsy, histological evaluation confirmed the former diagnostic and technical findings; in addition, pulmonary calcifications were detected morphologically which had not been seen on the chest radiograph. The significance of progressive organ calcifications for the prognosis of recovery has been discussed.

Three cases of neonatal herpes simplex virus infection presenting as fulminant hepatitis.

We report three cases of neonatal herpes simplex virus (HSV) infection presenting as fulminant hepatitis. None of the patients had clear risk factors for HSV infection and they all died. Antiviral treatment for HSV is currently available but must be administered early in the course of the disease before irreversible liver tissue damage is present. Since the diagnosis may be difficult to establish, we wish to draw the attention of clinicians to the presentation of neonatal HSV infection and suggest that in such cases viral cultures, including culture of liver tissue, should be obtained early and antiviral treatment administered while awaiting the culture results.

[Simultaneous double fluorescence flow cytometry of lysed whole blood for prenatal diagnosis of combined immunodeficiency]. / Simultane Doppelfluoreszenz-Flowzytometrie aus lysiertem Vollblut zur pränatalen Diagnostik eines kombinierten Immundefektes.

Simultaneous two-color flow cytometry of lysed whole blood allows the collection of maximal information from minimal blood volumes. This method was used for prenatal diagnosis of severe combined immunodeficiency by analysis of fetal blood. The data demonstrate that flow cytometry of lysed whole blood provides a reliable tool for prenatal diagnosis of certain immunodeficiencies. Moreover, the method described seems highly suitable for immunological monitoring of preterm infants and newborns. To enable the diagnosis of more subtle immunodeficiency states in these patients, however, valid normal values for all investigated parameters need to be defined first for the respective age/weight groups.

Engraftment of T-depleted major histocompatibility complex-mismatched bone marrow in T-deficient versus natural killer-deficient recipients.

When bone marrow transplantation recipients undergo standard pre-transplant immunosuppressive therapy, engraftment failures are significantly more frequent with the use of T-depleted allogeneic donor bone marrow cells than with T cell-containing allogeneic donor bone marrow cells. The relative importance of T versus natural killer (NK) cells in the rejection process of T-depleted donor bone marrow cells remains debatable. Here, NK- and T-deficient mouse mutants were transplanted across the same major histocompatibility complex (MHC) differences with homozygous or heterozygous T-depleted bone marrow cells. Results show that under the experimental conditions described, residual host NK cells are almost exclusively responsible for the increased rejection rate.

Long-term follow-up of children with surgically treated vesicorenal reflux: postoperative incidence of urinary tract infections, renal scars and arterial hypertension.

With a mean follow-up of 10.8 years, 160 female and 29 male patients were investigated after successful correction of vesicoureterorenal reflux. All patients suffered from urinary tract infection (UTI) preoperatively, while postoperatively 42% of the patients developed further UTIs but with a significantly diminished rate of febrile infections. In comparison to a group of patients without postoperative UTI (n = 16), the uroepithelial cells of those patients with a high infection rate after reflux correction showed a significantly lower bacterial growth suppression (n = 37). Renal scars were found in 22% of the investigated renal units with operated ureters (n = 211). Of the preoperatively unscarred kidneys, 3.4% developed new scars during the observation period, mainly within the first 2 years after operation. In 7 (11.5%) of the 61 patients with renal scars, moderate arterial hypertension was found.

Antibacterial capacity of buccal epithelial cells from healthy donors and children with recurrent urinary tract infections.

The effect of buccal epithelial cells (BEC) on bacterial growth was investigated in healthy subjects as well as in patients with recurrent urinary tract infections (UTI) and compared to the antibacterial capacity of uroepithelial cells (UEC) of the same individuals. Epithelial cells were obtained from the following groups: healthy female controls; females without further UTI after reflux operation; females with asymptomatic bacteriuria (ABU); females with further UTI despite successful reflux operation; and patients with meningomyelocele (MMC) and recurrent UTI due to significant residual urinary volume. Cocultivation of Escherichia coli with BEC as well as UEC from healthy females or patients with MMC resulted in significant suppression of bacterial growth. However, neither type of epithelial cell showed an antibacterial effect when they were obtained from patients with recurrent UTI in the absence of urological abnormalities (ABU patients; reflux-corrected patients with further UTI). From these results it is concluded that a generalised epithelial defence defect is one important pathogeneic factor for recurrent idiopathic UTI.

Intrathymic tolerance induction: determination of tolerance to class II major histocompatibility complex antigens in maturing T lymphocytes by a bone marrow-derived non-lymphoid thymus cell.

Two new experimental approaches were established to analyse the influence of the thymus on tolerance induction to major histocompatibility complex (MHC) antigens: The aim of the first experiment was to perform successful transplantation of adult allogeneic thymus tissue into nude mice, an attempt that has been unsuccessful in the past. Tolerance for the MHC genotype of a prospective thymus graft recipient (A) was induced in mice of strain B by injection of (A X B) splenocytes during the neonatal period. Adult thymic tissue obtained from these allogeneic donors (B) were grafted into the nude mice of strain A. The allogeneic thymus was accepted by the nude mice and immunoreconstitution was achieved. Subsequently the recipients developed tolerance to the MHC antigens of the allogeneic thymus donor as proved by mixed lymphocyte cultures and the acceptance of skin grafts. The second experiment was designed to determine which Ia-positive thymic compartment participates in conferring tolerance to MHC antigens in maturing T lymphocytes. Chimaeric thymus grafts were created by transplantation of neonatal thymus (A) into allogeneic nude mice (B) for a period of 8 weeks. The graft was populated with host bone marrow-derived Ia antigen-positive cells. The chimaeric thymuses consisting of type A epithelium but populated with both type A and B lymphocytes and non-lymphoid cells (i.e. Ia-positive macrophages and dendritic cells), were newly transplanted into nude mice of strain A. The engraftment lead to immunological reconstitution and the nude mice acquired tolerance to the MHC antigens expressed by the allogeneic Ia-positive cells populating the chimaeric graft. Irradiation of the chimaeric thymus prior to transplantation allowed transplantation of chimaeric thymus devoid of living thymocytes but still populated with functionally intact Ia-positive non-lymphoid cells. Transplantation of irradiated chimaeric thymuses resulted in immunoreconstitution and induced exactly the same allotolerance pattern as described above. The results demonstrate that not thymus epithelial cells but a bone-marrow-derived non-lymphoid thymus cell, most likely the Ia-antigen-positive thymic macrophage of dendritic cell, is responsible for the induction of tolerance to MHC antigens in developing T lymphocytes.

[Clinical course and scar development in operated vesico-renal reflux in a long-term study]. / Klinischer Verlauf und Narbenentwicklung beim operierten vesico-renalen Reflux in einer Langzeitbeobachtung.

62 patients (14 boys, 48 girls) representing 85 refluxive renal units (Grade 2-4) were investigated after successful operation for the development of further urinary tract infections (UTI) and renal scars (RS). The mean follow-up was 9.3 years. With the exception of one boy, none of the male patients developed any UTI or new RS. A similar result was obtained for about 45% of the girls. These two groups of patients presented with high-grade reflux before surgery. The remaining female patients (about 55%), however, presenting with lower-grade reflux before surgical treatment, developed further UTI as well as new RS despite surgical correction of their reflux. Investigations on the capacity of uroepithelial cells (UEC) to suppress bacterial growth revealed a deficient antibacterial effect of UEC in these patients. Such an UEC defect has also been shown in patients with asymptomatic bacteriuria. In conclusion, different reasons seem to be responsible for recurrent UTI and the development of RS in patients with reflux.

Comparison of the antibacterial effect of uroepithelial cells from healthy donors and children with asymptomatic bacteriuria.

Bacterial attachment to uroepithelial cells (UEC) and the effect of UEC on bacterial growth was investigated in 15 healthy persons and 12 patients suffering from asymptomatic bacteriuria (ABU) with recurrent urinary tract infections (UTI). Desquamated UEC and mannose-resistant Escherichia coli were co-cultivated for up to 90 min. While no difference in bacterial adherence was observed between healthy controls and patients, 33.4% of the bacteria attached to normal UEC were found to be dead under microscopic evaluation (acridine orange staining), whereas no killing effect could be observed in patients' UEC 5 min after the onset of incubation. This phenomenon was confirmed by investigating the E. coli growth rate in the presence of UEC, measured by counting bacterial colony forming units (CFU) on agar plates. While E. coli showed exponential growth in RPMI medium, the addition of normal UEC suppressed bacterial growth (P less than 0.01). UEC from patients with ABU, however, did not show this effect. It has been concluded that bacterial adhesion may initiate an epithelial defence function, present in healthy controls and lacking in ABU patients.

Macrophage subpopulations regulate intrathymic T-cell development. I: Ia-positive macrophages augment thymocyte proliferation.

The contribution of H2-Ia-positive thymic macrophages (Ia 1 thymic M phi) to intrathymic lymphopoiesis was investigated. An isolation method yielding cell suspensions highly enriched for Ia+ thymic M phi was performed. Cocultivation of these Ia+ thymic M phi with thymocytes showed that, while not affecting spontaneously proliferating thymocytes, the Ia+ thymic M phi strongly augmented the mitogen-induced proliferation of thymocytes by about 200%. This effect was dependent on the number of Ia+ M phi added as well as on the degree of thymocyte maturity: stronger augmentation occurred at higher concentrations of M phi and immature thymocytes showed highest susceptibility to the Ia+ thymic M phi-mediated effect. Cytochalasin B was employed to prove that cellular interaction is an important prerequisite for the proliferation amplifying effect of Ia+ thymic M phi. Additionally, humoral factors produced by Ia+ thymic M phi after induction with LPS are also involved in the described phenomenon. Furthermore, the use of interleukin preparations in the thymocyte-Ia+ M phi cocultures demonstrated that humoral factors support or probably regulate the interaction of these cells. The implications of these findings in view of the proliferation and differentiation events of thymocytes within the thymus are discussed.