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Factor H (CFH) autoantibodies are associated with atypical hemolytic uremic syndrome (aHUS). Peritransplantation plasma exchange therapy and intensification of immunosuppression, with adjuvant use of anti‐CD20 monoclonal antibodies has recently been advocated for cases of CFH‐autoantibody associated aHUS. In this report, we describe successful deceased donor renal transplantation in a case of CFH‐autoantibody associated aHUS with combined CFHR1 and 3 deficiency in addition to the CFH sequence variant, (cG2850T, pGln950His). CFH‐autoantibodies were detected 2 weeks prior to transplantation. Disease recurrence was not observed using basiliximab, an IL2‐receptor antagonist and high‐dose corticosteroids with mycophenolate mofetil. Adjuvant therapies such as Rituximab nor intensification of plasma therapy were employed. Consequently, careful consideration needs to be given to the use of additional immunosuppression in certain cases of CFH‐autoantibody associated aHUS. Serial measurement of CFH‐autoantibodies is required in the immediate pre‐ and posttransplantation period to further clarify their role as a factor in the recurrence of aHUS posttransplantation. Furthermore, delineation of the functional significance of CFH‐autoantibodies is warranted in individual cases.

Chronic lung disease (CLD) of prematurity is an inflammatory disease with a multifactorial etiology. The importance of Ureaplasma urealyticum in the development of CLD is debated, and steroids produce some improvement in neonates with this disease. In the present study, the capability of U. urealyticum to stimulate rat alveolar macrophages to produce nitric oxide (NO), express inducible nitric oxide synthase (iNOS), and activate nuclear factor kappaB (NF-kappaB) in vitro was characterized. The effect of NO on the growth of U. urealyticum was also investigated. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticum antigen (> or =4 x 10(7) color-changing units/ml) stimulated alveolar macrophages to produce NO in a dose- and time-dependent manner (P<0.05). This effect was further enhanced by gamma interferon (100 IU/ml; P<0.05) but was attenuated by budesonide and dexamethasone (10(-4) to 10(-6) M) (P<0.05). The mRNA and protein levels of iNOS were also induced in response to U. urealyticum and inhibited by steroids. U. urealyticum antigen triggered NF-kappaB activation, a possible mechanism for the induced iNOS expression, which also was inhibited by steroids. NO induced by U. urealyticum caused a sixfold reduction of its own growth after infection for 10 h. Our findings imply that U. urealyticum may be an important factor in the development of CLD. The host defense response against U. urealyticum infection may also be influenced by NO. The down-regulatory effect of steroids on NF-kappaB activation, iNOS expression, and NO production might partly explain the beneficial effect of steroids in neonates with CLD.

ABSTRACTChronic lung disease (CLD) of prematurity is an inflammatory disease with a multifactorial etiology. The importance ofUreaplasma urealyticumin the development of CLD is debated, and steroids produce some improvement in neonates with this disease. In the present study, the capability of U. urealyticumto stimulate rat alveolar macrophages to produce nitric oxide (NO), express inducible nitric oxide synthase (iNOS), and activate nuclear factor κB (NF-κB) in vitro was characterized. The effect of NO on the growth of U. urealyticumwas also investigated. In addition, the impact of dexamethasone and budesonide on these processes was examined. We found that U. urealyticumantigen (≥4 × 107color-changing units/ml) stimulated alveolar macrophages to produce NO in a dose- and time-dependent manner (P< 0.05). This effect was further enhanced by gamma interferon (100 IU/ml; P< 0.05) but was attenuated by budesonide and dexamethasone (10−4to 10−6M) (P< 0.05). The mRNA and protein levels of iNOS were also induced in response to U. urealyticumand inhibited by steroids.U. urealyticumantigen triggered NF-κB activation, a possible mechanism for the induced iNOS expression, which also was inhibited by steroids. NO induced by U. urealyticumcaused a sixfold reduction of its own growth after infection for 10 h. Our findings imply that U. urealyticummay be an important factor in the development of CLD. The host defense response againstU. urealyticuminfection may also be influenced by NO. The down-regulatory effect of steroids on NF-κB activation, iNOS expression, and NO production might partly explain the beneficial effect of steroids in neonates with CLD.

In 14 adolescents with diabetes, the postprandial blood glucose, after ingestion of two popular snacks, milk chocolate bar and potato chips, was compared to a prescribed mid-afternoon snack that was isocaloric with the comparison snacks. The prescribed diabetes snack consisted of wholemeal wheat bread, margarine, cheese and apple (1533 kJ/365 kcal): 14% protein, 32% fat and 54% carbohydrate. The milk chocolate bar and the potato chips contained 4% protein, 55% fat and 41% carbohydrate. The mean blood glucose peak was 4.7 (±0.8) mmol/l after the regular diabetes snack, after the milk chocolate bar 2.9 (±0.6) mmol/l, and 3.2 (±0.6) mmol/l after the potato chips (P>0.05). The mean incremental area under the blood glucose curve was 450.3 (±105.5) mmol/l×180 min for the regular diabetes snack, 269.5 (±96.7) mmol/l×180 min for the milk chocolate bar and 191.7 (±95.0) mmol/l×180 min for the potato chips (P>0.05). We conclude that an occasional isocaloric amount of milk chocolate bar or potato chips has no negative impact on the postprandial blood glucose.

Summary The aim of the present investigation was to study the intestinal colonization ofEscherichia coli in newborn children, and to determine which strains become residential within the human intestine. TheE. coli flora of 89 newborn children was studied by repeated sampling during their first 11 or 18 months of life. TheE. coli isolates from the samples were subdivided into phenotypes by the aid of biochemical finger-printing, a method which measures the kinetics of 24 selected biochemical tests as a tool for discriminating bacterial strains. It was found thatE. coli strains colonizing children soon after birth persisted longer than strains colonizing them later. Especially those phenotypes which were defined as hospital strains persisted longer. Certain phenotypes were commonly found among the children, and these phenotypes were more persistent and more homogeneous than other phenotypes with respect to their pattern of biochemical activities. They might be specially adapted to colonize the human intestine. It was concluded that the generally long persistence of the firstE. coli strains colonizing a newborn child indicates that the first case of bacterial colonization in children may be an event too important to be allowed to happen at random.

TEM-1, OXA-1, SHV-1, and related beta-lactamases in fecal isolates from 953 infants in 22 Swedish neonatal intensive care units were studied by DNA hybridization. TEM-1- and OXA-1-positive isolates were always Escherichia coli and represented 86 and 8%, respectively, of the ampicillin-resistant isolates of this species. SHV-1 was found in 16% of the Klebsiella sp. (mainly Klebsiella pneumoniae) isolates. TEM-1 and SHV-1 occurred in 14 and 16 units and in up to 64 and 26% of the neonates, respectively. On average, two to four different biochemical phenotypes per species per ward were positive for each beta-lactamase. All but 1 of the 33 E. coli phenotypes found to be TEM-1 positive were uniformly positive for the beta-lactamase gene, whereas some of the phenotypes found to be positive for OXA-1 (2 of 3) and SHV-1 (6 of 70) were occasionally negative for the respective genes. The occurrence of the three beta-lactamases studied tended to be associated with local ampicillin usage (correlation coefficient, 0.31 to 0.39; P greater than 0.05). Of the neonates receiving ampicillin, 30% carried TEM-1-positive E. coli, compared with 13% for cephalosporin-treated neonates and 15% for untreated neonates (P less than or equal to 0.001). The corresponding rates for SHV-1 in Klebsiella spp. were 18, 13, and 9% (P less than or equal to 0.01). Ampicillin is thus a significant risk factor for the maintenance of the most prevalent gram-negative plasmid-mediated beta-lactamases in hospitalized neonates.

Abstract

The faecal colonization withClostridium difficile was investigated among 343 infants during their first 18 months of life. Rectal swabs were taken at the ages of 6 days, 6 weeks, 6 months, 11 months and 18 months. About 25 % of the children were colonized withClostridium difficile between 6 days and 6 months of age. The colonization rate decreased to 3 % at 18 months of age. The rate of strains producing cytotoxin was low in infants less than 6 months of age, but at that age about half of the strains isolated were toxin-producing. Breast-fed children were significantly less often colonized withClostridium difficile than were bottle-fed infants, both at 6 weeks of age (21 % versus 47 %, p<0.05) and at 6 months of age (19 % versus 39 %, p<0.001). Colonization withClostridium difficile at 6 months of age was associated with a greater frequency of diarrhoeal disease between 6 and 11 months of age (27 % versus 16 %, p<0.05). This association was even more pronounced when the bacteria persisted at 11 months of age (54 %, p<0.01). Antibiotic therapy could not be demonstrated to influence colonization withClostridium difficile at any age.

A total of 323Escherichia coli strains from children with primary acute non-obstructive pyelonephritis (n=144) or cystitis (n=56) and from adults with acute non-obstructive pyelonephritis (n=66) or cystitis (n=57) were examined for presence of the aerobactin-mediated iron uptake system and expression of P-fimbriae. Overall, pyelonephritogenicEscherichia coli strains were significantly more often aerobactin-positive (72 %) than cystitis strains (42 %) (p<0.001). Seventy-three percent of the isolates from children with acute pyelonephritis were aerobactin-positive compared to 54 % of the cystitis strains (p<0.05). PyelonephritogenicEscherichia coli strains from adults were also significantly more often aerobactin-positive (70 %) than cystitis strains (30 %) (p<0.001). The cystitis strains from children were more often aerobactin-positive than cystitis strains from adult patients (p<0.05). There was a significant correlation between presence of the aerobactin-mediated iron uptake system and expression of P-fimbriae in all strains (p<0.001).

Streptococcus agalactiaetransmitted to infants from the vagina during birth is an important cause of invasive neonatal infection. We have done a prospective, randomised, double-blind, placebo-controlled, multi-centre study of chlorhexidine prophylaxis to prevent neonatal disease due to vaginal transmission of S agalactiae.

AIM: To investigate if early changes in concentrations of proinflammatory cytokines in tracheobronchial aspirate fluid (TAF) from preterm infants could be used to detect infants at risk of chronic lung disease (CLD) and help in the selection of patients for early steroid treatment. METHODS: Twenty eight preterm infants less than 34 weeks of gestation (median 26 weeks) were intubated and daily measurements of TAF concentrations of tumour necrosis factor alpha (TNF alpha) and the interleukins IL-1 beta, IL-6, and IL-8 were made, using enzyme immunoassay techniques. RESULTS: Seventeen of the infants developed CLD. The infants who developed CLD had significantly increased concentrations of TNF alpha, IL-1 beta, IL-6 on days 2 and 3. TNF alpha, IL-6, and IL-8 concentrations were significantly related to gestational age and duration of supplemental oxygen; TNF alpha, IL-6, and IL-8 concentrations also correlated with length of time on the ventilator. CONCLUSION: These data indicate that tracheobronchial aspirate fluid cytokine concentrations may be used as a predictor of subsequent CLD and may help select a group of preterm infants at high risk of developing CLD for early treatment.

We compared the urinary concentrations of soluble TNF‐I (sTNF‐RI), TNF‐II receptors, and soluble IL‐6 receptor (sIL‐6R) standardized to urinary creatinine concentrations, in children with acute pyelonephritis, in children with non‐renal fever and in healthy controls. These levels were related to the acute inflammatory response in the kidneys and later renal scarring, as determined by acute and 1‐y follow‐up with 99mTC‐dimercaptosuccinic acid scintigraphy (DMSA). The concentrations of the soluble receptors were measured using enzyme immunoassay (EIA). The urinary levels of sTNF‐RI were significantly higher in children with acute pyelonephritis (median 1320 pg/mmol) than in children with non‐renal fever, children 6 weeks after acute pyelonephritis and healthy controls (873, 251 and 477 pg/μmol, respectively). Median sTNF‐RII urine levels were also higher in acute pyelonephritis (4123 p/μmol) than in the three control groups (2000, 964 and 1850 pg/μmol, respectively). In contrast, the highest urinary sIL‐6R concentrations were found in healthy children (median 420 pg/μmol). compared to those with acute pyelonephritis (235 pg/μmol), children with non‐renal fever and children 6 weeks after pyelonephritis (137 and 50 pg/μmol, respectively). No significant difference was found in any of the urinary soluble receptor levels in children with or without DMSA uptake defects at the acute or the 1‐y follow‐up scintigraphy. In conclusion, although the urinary soluble TNF receptor levels were higher during acute pyelonephritis, this observation was not useful for deciding which children needed follow‐up after acute pyelonephritis.

Summary Gram-negative bacteria are an important cause of invasive infection among neonates. In this study a novel fingerprinting method was used for the first time to assess the importance of various potential reservoirs of the major gram-negative enterobacteria that colonized 46 consecutive infants in three neonatal special care units during a three to four week period. Such bacteria were isolated from the oropharynx, umbilical cord and faeces in 24%, 33% and 100% of the infants, respectively.Klebsiella/Enterobacter spp. dominated overEscherichia coli and spreading (shared) over sporadic strains. Sixty-one percent of the neonates were colonized with at least one and up to six different strains shown to exist in the ward, mainly in other infants. Environmental reservoirs and the faecal flora of mothers and staff were of minor importance. Vertical transmission occurred in 12% of vaginally delivered infants and in 0% of those delivered by caesarean section.

Fecal colonization with P-fimbriatedEscherichia colihas caused epidemic outbreaks of extraintestinalE. coliinfections in the neonatal unit of Danderyd Hospital. The aerobic fecal flora was therefore studied in 1,955 newborn children born at Danderyd Hospital during a period of 2.5 years.E. coliwas found in 58% of the maternity ward children and in 57% of the neonatal unit children. A P-fimbriated strain was found in 12% and 17% of the children, respectively (p<0.01). There was a significant increase in the frequency of children colonized withE. coli, and especially P-fimbriatedE. coli, with length of stay in the neonatal unit. There was a statistical correlation between bed occupancy and colonization with P-fimbriatedE. coli(r=0.46, p<0.01) during this study period. We found an incidence of P-fimbriatedE. coliof 10 to 20% among theE. colistrains isolated from the fecal specimens which we regard as the baseline incidence. Durch fäkale Kolonisation Neugeborener mit P-Fimbrien tragendenEscherichia colitraten auf der Neugeborenenstation des Danderyd Hospital Epidemien extraintestinalerE. coli-Infektionen auf. Daher wurde über einen Zeitraum von zweieinhalb Jahren die aerobe Darmflora bei 1955 im Danderyd Hospital geborenen Neugeborenen untersucht. Bei 58% der Kinder der Entbindungsstation und bei 57% der Kinder der Neugeborenenstation wurdenE. coliim Stuhl nachgewiesen. P-Fimbrien tragendeE. colifanden sich bei 12% der Kinder der Entbindungsstationen und bei 17% der Kinder der Neugeborenenstationen (p<0,01). Die Inzidenz von mitE. colikolonisierten Kindern, vor allem aber der Kolonisation mit P-Fimbrien tragendenE. coli, nahm mit der Verweildauer auf der Neugeborenenstation signifikant zu. Es bestand außerdem eine statistisch signifikante Korrelation zwischen Belegdichte und Kolonisation mit P-Fimbrien tragendenE. coli(r=0,46; p<0,01) während der Untersuchungsphase. Wir nehmen an, daß die in unserer Studie festgestellte Inzidenz von 10 bis 20% P-Fimbrien tragendenE. coliunter den aus Stuhlproben isoliertenE. coli-Stämmen die Basisinzidenz repräsentiert.

Theoretically there are several ways to prevent pyelonephritis and renal scarring caused by P-fimbriatedEscherichia coli. Screening for individuals at risk, e.g. those carrying P-fimbriated pyelonephritogenicE. colior those with high receptor density on their uroepithelial cells, could perhaps define a population where prophylaxis with a receptor analogue or vaccination with P-fimbriae may be relevant. Epidemiological measures in neonatal and maternity wards may prevent the nosocomial spread of virulent bacteria and reduce the number of colonized infants. However, no such methods have so far had any proven clinical relevance, and today, the important concern is still to try by conventional means — as we have always done — to get an early diagnosis and to treat the patient without delay. Theoretisch gibt es verschiedene Möglichkeiten, die durch P-Fimbrien-tragendeEscherichia coliverursachte Pyelonephritis und renale Narbenbildung zu verhüten. Ein Screening auf Risikopersonen, beispielsweise diejenigen, die mit P-Fimbrien-tragenden pyelonephritogenenE. colibesiedelt sind oder deren uroepitheliale Zellen eine hohe Rezeptordichte haben, könnte vielleicht eine Gruppe definieren, bei der eine Impfung mit einem Rezeptor-Analogon oder mit P-Fimbrien wichtig wäre. Epidemiologische Maßnahmen auf Neugeborenen- und Entbindungsstationen könnten die nosokomiale Verbreitung von virulenten Bakterien verhüten und die Anzahl besiedelter Säuglinge vermindern. Jedoch ist bisher für keine der genannten Methoden der Beweis der klinischen Effizienz erbracht, und derzeit ist es immer noch entscheidend, konventionelle Methoden einzusetzen, um, wie wir es immer getan haben, frühzeitig die Diagnose zu stellen und den Patienten ohne Verzug zu behandeln.

The Phene Plate (PhP) biochemical fingerprinting system for bacteria is based on measurements of the kinetics of bacterial biochemical reactions. This system was modified for typing of enterococci and was compared with DNA typing by pulsed-field gel electrophoresis and with ribotyping by using 45 Enterococcus faecalis isolates from international collections. It was also used to study 170 fecal enterococcal isolates from healthy individuals and 28 isolates of E. faecalis from the blood of neonates. The PhP system showed a high degree of discriminatory power for unrelated enterococcal isolates. Among the 170 unrelated fecal isolates, 107 isolates from international collections, PhP typing discriminated 19 types, and ribotyping discriminated 5 types. In most cases, when isolates were of the same DNA type, they were also of the same PhP type, and the level of agreement between these two methods was high (96%). A combination of PhP typing and DNA typing identified 34 different types, but ribotyping did not yield any further discrimination. PhP typing of E. faecalis isolates from healthy individuals (n = 89) and from the blood of neonates with septicemia (n = 28) yielded a diversity of 0.93 for both populations and similar major PhP types in both populations. Thus, the isolates from blood seemed to consist of a normal E. faecalis population, without a dominance of certain strains associated with virulence. We conclude that the PhP system is useful for epidemiological studies of enterococcal isolates, yielding results similar to those obtained with DNA typing by pulsed-field gel electrophoresis. Since PhP typing is a method that is simple and rapid and that is based on automatic evaluation of the data, it is suitable for analyzing large numbers of isolates and can be used alone or in combination with DNA typing or epidemiological and ecological studies of enterococci.

The gram-negative fecal floras from 953 infants were studied upon discharge of the infants from 22 neonatal wards. More than 600 distinct phenotypes of Escherichia coli, Klebsiella spp., and Enterobacter spp. were distinguished by high-resolution biotyping. The colonization patterns observed showed considerable local and temporal variation. The major (M) strains (phenotypes), which colonized more than 10% and up to 78% of the infants in a ward (median, 23%), were Klebsiella oxytoca (15 strains), E. coli (4 strains), Klebsiella pneumoniae (1 strain), and Enterobacter cloacae (1 strain). Resistance to beta-lactam antibiotics was more pronounced among M strains than among strains of enteric bacteria colonizing few or single infants only. Local antibiotic policy influenced the colonization patterns. Despite the fact that M strains of Klebsiella spp. were usually resistant to ampicillin as well as to cephalexin and cefuroxime, their local dissemination was associated with the use of ampicillin with or without gentamicin but not with the use of cefuroxime. It thus appeared that in the neonatal setting, ampicillin posed a greater risk of local spread of certain drug-resistant bacterial clones than a newer cephalosporin, such as cefuroxime.

Two hundred and thirty-two strains ofEscherichia coli isolated from children with non-obstructive acute pyelonephritis (n=65), women with non-obstructive acute pyelonephritis (n=63) and the faecal flora of healthy children (n=33) and adults (n=71) were examined for cytotoxic necrotizing factor production, haemolysin synthesis, verocytotoxin production and expression of mannose-resistant haemagglutination of human erythrocytes. Forty-eight per cent of the pyelonephritogenicEscherichia coli strains produced cytotoxic necrotizing factor and 61 % produced haemolysin compared to 25 % and 27 % of faecal control strains (p<0.001 and p<0.001 respectively). Cytotoxic necrotizing factor production did not occur among the non-haemolyticEscherichia coli strains which confirms the close association between these two toxic factors. The bacterial phenotypes producing both haemolysin and cytotoxic necrotizing factor, and the phenotype expressing both these toxic factors and mannose-resistant haemagglutination occurred significantly more often in pyelonephritogenic strains than in faecal isolates (p<0.001). Haemolytic strains without the ability to produce cytotoxic necrotizing factor were more common in faecal isolates than in uropathogenic strains (p=0.05). Strains lacking the ability to synthesize both these toxins were also over-represented in faecal isolates (p<0.01).

The aim of the study was to investigate the properties of fecal P-fimbriatedEscherichia colistrains in neonates and to relate these characteristics to the later development of acute pyelonephritis. In a 2 1/2 year prospective study of the children admitted to a particular neonatal ward, 113 children were found to be fecally colonized with a P-fimbriatedEscherichia colistrain. However, only one of these children developed pyelonephritis from this strain during the first year of life. The combined results of serotyping, biochemical phenotyping and determination of outer membrane protein pattern as clonal characterization suggested that only 26 of the P-fimbriated strains belonged to a pyelonephritogenicEscherichia coliclone. It is concluded that the risk of a child colonized with anEscherichia colistrain belonging to such a clone of developing pyelonephritis, as calculated in this study, is about 4 %.

The relationship between urine interleukin-6 (IL-6) and interleukin-8 (IL-8)/creatinine quotients and99mTc-dimercaptosuccinic acid (DMSA) scintigraphy, performed within 10 days of acute first-time pyelonephritis and after 1 year, was studied in 41 children. The urine IL-6 and IL-8/creatinine quotients were also related to the urineN-acetyl-β-D-glucosaminidase (NAG) and albumin/creatinine quotients. Presence of DMSA uptake defects, reflecting local inflammation, in children in the acute phase of pyelonephritis, were associated with elevated urine IL-6/creatinine quotients (median 27 pg/μmol); in children without DMSA changes there was no increase in quotients (median non-detectable) (P<0.05). Persistent DMSA changes at the 1-year follow-up, probably reflecting renal scarring, were only seen in children with increased urine IL-6/creatinine quotients in the acute phase (P<0.01). No correlation was found between urine IL-8 and DMSA uptake defects. Vesicoureteral reflux (VUR) at 6–8 weeks did not correlate with the urine cytokine levels in the acute phase. The urine excretion of NAG and albumin, reflecting renal dysfunction, was associated with values of both urine IL-6 and IL-8/creatinine quotients, but not with DMSA defects or VUR. Thus, the initial urine IL-6/creatinine quotients might be used as an indicator of risk for persistent renal damage in acute pyelonephritis.

Both ampicillin and cefuroxime therapy of neonates selected drug- and species-dependent beta-lactam resistance patterns in fecal strains of Escherichia coli and Klebsiella spp. This was in contrast to our previous findings that ampicillin, but not cefuroxime, contributed to the emergence of beta-lactam resistance also by the promotion of nosocomial spread of resistant strains.

Summary The importance of fecal colonization with P-fimbriatedEscherichia coli for the later development of pyelonephritis was studied among infants before the age of 11 months. In contrast to previous studies, the fecal colonization with a P-fimbriatedE. coli strain did not increase the incidence of acute pyelonephritis.