Different populations of A(H1N1)pdm09 viruses in a patient with hemolytic-uremic syndrome

Respiratory viral infections may have different impacts ranging from infection without symptoms to severe disease or even death though the reasons are not well characterized. A patient (age group 5-15 years) displaying symptoms of hemolytic uremic syndrome died one day after hospitalization. qPCR, next generation sequencing, virus isolation, antigenic characterization, resistance analysis was performed and virus replication kinetics in well-differentiated airway cells were determined. Autopsy revealed hemorrhagic pneumonia as major pathological manifestation. Lung samples harbored a large population of A(H1N1)pdm09 viruses with the polymorphism H456H/Y in PB1 polymerase. The H456H/Y viruses replicated much faster to high viral titers than upper respiratory tract viruses in vitro. H456H/Y-infected air-liquid interface cultures of differentiated airway epithelial cells did reflect a more pronounced loss of ciliated cells. A different pattern of virus quasispecies was found in the upper airway samples where substitution S263S/F (HA1) was observed. The data support the notion that viral quasispecies had evolved locally in the lung to support high replicative fitness. This change may have initiated further pathogenic processes leading to rapid dissemination of inflammatory mediators followed by development of hemorrhagic lung lesions and fatal outcome.

Kidney outcomes in Shiga toxin-associated hemolytic uremic syndrome in childhood: A retrospective single-center study from 1999 to 2017: Kidney outcomes in typical hemolytic uremic syndrome in childhood

BACKGROUND

Shiga toxin-associated hemolytic uremic syndrome (STECHUS) is the main cause of acute kidney injury in children and may be responsible for adverse outcomes despite an apparent quiescent period.

OBJECTIVE

To describe the medium- and long-term kidney outcomes of pediatric STECHUS in a French region.

METHODS

A single-center, descriptive, retrospective study of STECHUS cases that occurred at Besançon University Hospital between 1999 and 2017 in children up to 17 years of age was conducted. The primary study endpoint was the proportion of chronic kidney disease (CKD) cases at 5 years of follow-up.

RESULTS

We included 98 consecutive patients. Among the 71 patients at the 5-year follow-up, we found 24 (34 %) patients with no adverse kidney outcome, 18 (25 %) with moderate adverse kidney outcome, and one (1.4 %) with severe adverse kidney outcome. Among the 96 patients at 1 year from the diagnosis, these figures were, respectively, 25 (26 %), 51 (53 %), and two (2 %); and among the 38 patients at 10 years, they were, respectively, nine (24 %), 12 (32 %), and one (3 %). The glomerular filtration rate level and oliguria-anuria beyond 8 days at baseline were significantly associated with more severe kidney outcomes at 10 years (p = 0.03 and 0.005, respectively). Two patients died during the acute phase. Overall, 33 patients (34 %) were lost to follow-up.

CONCLUSION

Adverse kidney outcomes may appear many years after an episode of STECHUS despite an apparent quiescent period. Regular long-term monitoring is required. The challenge is to reduce the proportion of patients lost to follow-up with potentially severe adverse kidney outcomes and no evaluation or treatment.

Cardiovascular impairment in Shiga-toxin-2-induced experimental hemolytic-uremic syndrome: a pilot study

Introduction

Hemolytic-uremic syndrome (HUS) can occur as a systemic complication of infection with Shiga toxin (Stx)-producing Escherichia coli (STEC). Most well-known aspects of the pathophysiology are secondary to microthrombotic kidney disease including hemolytic anemia and thrombocytopenia. However, extrarenal manifestations, such as cardiac impairment, have also been reported. We have investigated whether these cardiac abnormalities can be reproduced in a murine animal model, in which administration of Stx, the main virulence factor of STEC, is used to induce HUS.

Methods

Mice received either one high or multiple low doses of Stx to simulate the (clinically well-known) different disease courses. Cardiac function was evaluated by echocardiography and analyses of biomarkers in the plasma (troponin I and brain natriuretic peptide).

Results

All Stx-challenged mice showed reduced cardiac output and depletion of intravascular volume indicated by a reduced end-diastolic volume and a higher hematocrit. Some mice exhibited myocardial injury (measured as increases in cTNI levels). A subset of mice challenged with either dosage regimen showed hyperkalemia with typical electrocardiographic abnormalities.

Discussion

Myocardial injury, intravascular volume depletion, reduced cardiac output, and arrhythmias as a consequence of hyperkalemia may be prognosis-relevant disease manifestations of HUS, the significance of which should be further investigated in future preclinical and clinical studies.

The Fatal Role of Enterohaemorrhagic Escherichia coli Shiga Toxin-associated Extracellular Vesicles in Host Cells

Enterohemorrhagic Escherichia coli (EHEC) is a specific subset of Shiga toxin-producing Escherichia coli (STEC) strains that are characterized by their ability to cause bloody diarrhea (hemorrhagic colitis) and potentially life-threatening, extraintestinal complications such as hemolytic uremic syndrome (HUS), which is associated with acute renal failure., contributing to severe clinical outcomes. The Shiga toxins (Stxs), produced by EHEC, are primary virulence factors. These potent cytotoxins are composed of one enzymatically active A subunit (StxA) and five receptor-binding B subunits (StxB). Although the toxins are primarily associated with cytotoxic effects, they also elicit other pathogenic consequences due to their induction of a number of biological processes, including apoptosis through ER-stress, pro-inflammatory responses, autophagy, and post-translational modification (PTM). Moreover, several studies have reported the association between Stxs and extracellular vesicles (EVs), including microvesicles and exosomes, demonstrating that Stx-containing EVs secreted by intoxicated macrophages are taken up by recipient cells, such as toxin-sensitive renal proximal tubular epithelial cells. This mechanism likely contributes to the spreading of Stxs within the host, and may exacerbate gastrointestinal illnesses and kidney dysfunction. In this review, we summarize recent findings relating to the host responses, in different types of cells in vitro and in animal models, mediated by Stxs-containing exosomes. Due to their unique properties, EVs have been explored as therapeutic agents, drug delivery systems, and diagnostic tools. Thus, potential therapeutic applications of EVs in EHEC Stxs-mediated pathogenesis are also briefly reviewed.

EFFECTS OF BACTERIAL LIPOPOLYSACCHARIDE AND SHIGA TOXIN ON INDUCED PLURIPOTENT STEM CELL-DERIVED MESENCHYMAL STEM CELLS

ABSTRACT

Background : Mesenchymal stem cells (MSCs) can be activated by different bacterial toxins. Lipopolysaccharides and Shiga Toxin (Stx) are the main toxins necessary for hemolytic uremic syndrome development. The main etiological event in this disease is endothelial damage that causes glomerular destruction. Considering the repairing properties of MSC, we aimed to study the response of MSC derived from induced pluripotent stem cells (iPSC-MSC) to LPS and/or Stx and its effect on the restoration of injured endothelial cells. Methods : iPSC-MSC were treated with LPS and or/Stx for 24 h and secretion of cytokines, adhesion, and migration were measured in response to these toxins. In addition, conditioned media from treated iPSC-MSC were collected and used for proteomics analysis and evaluation of endothelial cell healing and tubulogenesis using human microvascular endothelial cells 1 as a source of endothelial cells. Results : The results obtained showed that LPS induced a proinflammatory profile on iPSC-MSC, whereas Stx effects were less evident, even though cells expressed the Gb 3 receptor. Moreover, LPS induced on iPSC-MSC an increment in migration and adhesion to a gelatin substrate. Addition of conditioned media of iPSC-MSC treated with LPS + Stx, decreased the capacity of human microvascular endothelial cells 1 to close a wound, and did not favor tubulogenesis. Proteomic analysis of iPSC-MSC treated with LPS and/or Stx revealed specific protein secretion patterns that support the functional results described. Conclusions : iPSC-MSC activated by LPS acquired a proinflammatory profile that induces migration and adhesion to extracellular matrix proteins but the addition of Stx did not activate any repair program to ameliorate endothelial damage, indicating that the use of iPSC-MSC to regenerate endothelial injury caused by LPS and/or Stx in hemolytic uremic syndrome could not be the best option to consider to regenerate a tissue injury.

Neutrophil Extracellular Traps Induced by Shiga Toxin and Lipopolysaccharide-Treated Platelets Exacerbate Endothelial Cell Damage

Hemolytic uremic syndrome (HUS) is the most common cause of acute renal failure in the pediatric population. The etiology of HUS is linked to Gram-negative, Shiga toxin (Stx)-producing enterohemorrhagic bacterial infections. While the effect of Stx is focused on endothelial damage of renal glomerulus, cytokines induced by Stx or bacterial lipopolysaccharide (LPS) and polymorphonuclear cells (PMNs) are involved in the development of the disease. PMN release neutrophil extracellular traps (NETs) to eliminate pathogens, although NETs favor platelets (Plts) adhesion/thrombus formation and can cause tissue damage within blood vessels. Since thrombus formation and occlusion of vessels are characteristic of HUS, PMN–Plts interaction in the context of Stx may promote netosis and contribute to the endothelial damage observed in HUS. The aim of this study was to determine the relevance of netosis induced by Stx in the context of LPS-sensitized Plts on endothelial damage. We observed that Stx2 induced a marked enhancement of netosis promoted by Plts after LPS stimulation. Several factors seemed to promote this phenomenon. Stx2 itself increased the expression of its receptor on Plts, increasing toxin binding. Stx2 also increased LPS binding to Plts. Moreover, Stx2 amplified LPS induced P-selectin expression on Plts and mixed PMN–Plts aggregates formation, which led to activation of PMN enhancing dramatically NETs formation. Finally, experiments revealed that endothelial cell damage mediated by PMN in the context of Plts treated with LPS and Stx2 was decreased when NETs were disrupted or when mixed aggregate formation was impeded using an anti-P-selectin antibody. Using a murine model of HUS, systemic endothelial damage/dysfunction was decreased when NETs were disrupted, or when Plts were depleted, indicating that the promotion of netosis by Plts in the context of LPS and Stx2 plays a fundamental role in endothelial toxicity. These results provide insights for the first time into the pivotal role of Plts as enhancers of endothelial damage through NETs promotion in the context of Stx and LPS. Consequently, therapies designed to reduce either the formation of PMN–Plts aggregates or NETs formation could lessen the consequences of endothelial damage in HUS.

[The intermediate outcomes of delegation of obligations of medicinal support of patients with rare diseases to the Federal level in 2019-2020]

Lately, in case of a number of life-threatening and chronic progressive rare (orphan) diseases, resulting in decreasing of life expectancy of citizens or their disability, the powers to support patients with medications were transferred from regional to federal level. Among these diseases are hemolytic uremic syndrome, mucopolysaccharidose type I, II, VI, juvenile arthritis with systemic onset, unspecified aplastic anemia, hereditary deficiency of factors II (fibrinogen), VII (labile), X (Stuart-Prauer). The article considers data concerning hemolytic uremic syndrome, mucopolysaccharidosis type I, II, VI, juvenile arthritis with systemic onset - the diseases for which medication support provision was transferred to Federal level in the first place and for which at the time of preparation of the article there were sufficient data to analyze.

Therapeutic Antibodies Against Shiga Toxins: Trends and Perspectives

Shiga toxins (Stx) are AB₅-type toxins, composed of five B subunits which bind to Gb₃ host cell receptors and an active A subunit, whose action on the ribosome leads to protein synthesis suppression. The two Stx types (Stx1 and Stx2) and their subtypes can be produced by Shiga toxin-producing Escherichia coli strains and some Shigella spp. These bacteria colonize the colon and induce diarrhea that may progress to hemorrhagic colitis and in the most severe cases, to hemolytic uremic syndrome, which could lead to death. Since the use of antibiotics in these infections is a topic of great controversy, the treatment remains supportive and there are no specific therapies to ameliorate the course. Therefore, there is an open window for Stx neutralization employing antibodies, which are versatile molecules. Indeed, polyclonal, monoclonal, and recombinant antibodies have been raised and tested in vitro and in vivo assays, showing differences in their neutralizing ability against deleterious effects of Stx. These molecules are in different phases of development for which we decide to present herein an updated report of these antibody molecules, their source, advantages, and disadvantages of the promising ones, as well as the challenges faced until reaching their applicability.

[Obtaining new information on hemolytic uremic syndrome by text mining]

Hemolytic uremic syndrome (HUS) is characterized by thrombotic microangiopathy, hemolytic anemia, thrombocytopenia and acute renal failure. It can cause from permanent sequelae to death, mainly in children. In this work, using text mining (TM), we analyzed the explicit and implicit text of 16 192 original scientific articles on HUS indexed in the Europe PMC database. The objectives were to examine behaviors, track trends, and make predictions and cross-check data with other sources of information. For the analysis we used -among other computational tools- specially developed workflows (WF) in the KNIME platform. The TM on the words of the abstracts of the publications made it possible to: detect undescribed associations between events related to HUS; extract underlying information; make thematic clustering using unsupervised algorithms; make forecasting about the course of research associated with the topic. Both the approach and the WFs developed to perform Data Science on HUS can be applied to other biomedical topics and other scientific databases, making it possible to analyze relevant aspects in the field of human health to improve research, prevention and treatment of multiples diseases.

Whole-Genome Sequencing of Shiga Toxin-Producing Escherichia coli OX18 from a Fatal Hemolytic Uremic Syndrome Case

We report a fatal case of hemolytic uremic syndrome with urinary tract infection in Japan caused by Shiga toxin–producing Escherichia coli. We genotypically identified the isolate as OX18:H2. Whole-genome sequencing revealed 3 potentially pathogenic lineages (OX18:H2, H19, and H34) that have been continuously isolated in Japan.

Shiga Toxin-Associated Hemolytic Uremic Syndrome in Adults, France, 2009-2017

We conducted a retrospective study on hemolytic uremic syndrome caused by Shiga toxin–producing Escherichia coli (STEC) in 96 adults enrolled in the cohort of the National Reference Center for Thrombotic Microangiopathies network in France during 2009–2017. Most infections were caused by STEC strains not belonging to the O157 or O104 serogroups. Thirty (31.3%) patients had multiple risk factors for thrombotic microangiopathy. In total, 61 (63.5%) patients required dialysis, 50 (52.1%) had a serious neurologic complication, 34 (35.4%) required mechanical ventilation, and 19 (19.8%) died during hospitalization. We used multivariate analysis to determine that the greatest risk factors for death were underlying immunodeficiency (hazard ratio 3.54) and severe neurologic events (hazard ratio 3.40). According to multivariate analysis and propensity score-matching, eculizumab treatment was not associated with survival. We found that underlying conditions, especially immunodeficiency, are strongly associated with decreased survival in adults who have hemolytic uremic syndrome caused by STEC.

Role of Recent Therapeutic Applications and the Infection Strategies of Shiga Toxin-Producing Escherichia coli

Shiga toxin-producing Escherichia coli (STEC) is a global foodborne bacterial pathogen that is often accountable for colon disorder or distress. STEC commonly induces severe diarrhea in hosts but can cause critical illnesses due to the Shiga toxin virulence factors. To date, there have been a significant number of STEC serotypes have been evolved. STECs vary from nausea and hemorrhoid (HC) to possible lethal hemolytic-based uremic syndrome (HUS), thrombotic thrombocytopenic purpura (TTP). Inflammation-based STEC is usually a foodborne illness with Shiga toxins (Stx 1 and 2) thought to be pathogenesis. The STEC's pathogenicity depends significantly on developing one or more Shiga toxins, which can constrain host cell protein synthesis leading to cytotoxicity. In managing STEC infections, antimicrobial agents are generally avoided, as bacterial damage and discharge of accumulated toxins are thought the body. It has also been documented that certain antibiotics improve toxin production and the development of these species. Many different groups have attempted various therapies, including toxin-focused antibodies, toxin-based polymers, synbiotic agents, and secondary metabolites remedies. Besides, in recent years, antibiotics' efficacy in treating STEC infections has been reassessed with some encouraging methods. Nevertheless, the primary role of synbiotic effectiveness (probiotic and prebiotic) against pathogenic STEC and other enteropathogens is less recognized. Additional studies are required to understand the mechanisms of action of probiotic bacteria and yeast against STEC infection. Because of the consensus contraindication of antimicrobials for these bacterial pathogens, the examination was focused on alternative remedy strategies for STEC infections. The rise of novel STEC serotypes and approaches employed in its treatment are highlighted.

Urate Nephropathy from Tumor Lysis Syndrome in an Undiagnosed Case of Prostate Cancer

Prostate cancer can masquerade as just normocytic anemia and thrombocytopenia, thrombotic thrombocytopenic purpura (TTP), hemolytic uremic syndrome (HUS), or tumor lysis syndrome (TLS). We are reporting an intriguing case of metastatic prostate cancer which remained undiagnosed until the patient showed signs of tumor lysis syndrome (TLS), leading to urate nephropathy requiring urgent hemodialysis. Tumor lysis syndrome is an oncological emergency but an exceedingly rare complication in non-hematological malignancies, including prostate cancer. It is challenging to recognize features of TLS in a case such as this with an unknown diagnosis. In the case of an established diagnosis of malignancy, however, checking baseline renal function, uric acid, lactate dehydrogenase (LDH), potassium, and phosphate to monitor for TLS as well as considering urate lowering therapy can help prevent adverse outcomes.

Primary Human Derived Blood Outgrowth Endothelial Cells: An Appropriate In Vitro Model to Study Shiga Toxin Mediated Damage of Endothelial Cells

Hemolytic uremic syndrome (HUS) is a rare disease primarily characterized by hemolytic anemia, thrombocytopenia, and acute renal failure. Endothelial damage is the hallmark of the pathogenesis of HUS with an infection with the Shiga toxin (Stx) producing Escherichia coli (STEC-HUS) as the main underlying cause in childhood. In this study, blood outgrowth endothelial cells (BOECs) were isolated from healthy donors serving as controls and patients recovered from STEC-HUS. We hypothesized that Stx is more cytotoxic for STEC-HUS BOECs compared to healthy donor control BOECs explained via a higher amount of Stx bound to the cell surface. Binding of Shiga toxin-2a (Stx2a) was investigated and the effect on cytotoxicity, protein synthesis, wound healing, and cell proliferation was studied in static conditions. Results show that BOECs are highly susceptible for Stx2a. Stx2a is able to bind to the cell surface of BOECs with cytotoxicity in a dose-dependent manner as a result. Pre-treatment with tumor necrosis factor alpha (TNF-α) results in enhanced Stx binding with 20–30% increased lactate dehydrogenase (LDH) release. Endothelial wound healing is delayed in a Stx2a-rich environment; however, this is not caused by an effect on the proliferation rate of BOECs. No significant differences were found between control BOECs and BOECs from recovered STEC-HUS patients in terms of Stx2a binding and inhibition of protein synthesis.

Plasmapheresis in a case of acute kidney injury with severe hemolysis and thrombocytopenia due to hematotoxic (Russell's viper) snake bite

We present a case of a male patient after being bitten by a vasculotoxic snake (Russell's viper) with severe hemolysis, thrombocytopenia, and acute kidney injury requiring hemodialysis. As attempt to administer anti-snake venom (ASV) failed because of development of anaphylactic reaction, a single session of plasmapheresis was done to stop hemolysis and fall in platelets, which was refractory to all other measures and proved to be a lifesaving procedure in this patient. The role of plasmapheresis in the management of snakebite victims is yet to be established, but can be beneficial in snake bite victims refractory to ASV or nonavailability of ASV or intolerant to ASV as in this case.

Crosstalk between Human Microvascular Endothelial Cells and Tubular Epithelial Cells Modulates Pro-Inflammatory Responses Induced by Shiga Toxin Type 2 and Subtilase Cytotoxin

Hemolytic uremic syndrome (HUS) is a consequence of Shiga toxin (Stx)-producing Escherichia coli (STEC) infection and is the most frequent cause of acute renal failure (ARF) in children. Subtilase cytotoxin (SubAB) has also been associated with HUS pathogenesis. We previously reported that Stx2 and SubAB cause different effects on co-cultures of human renal microvascular endothelial cells (HGEC) and human proximal tubular epithelial cells (HK-2) relative to HGEC and HK-2 monocultures. In this work we have analyzed the secretion of pro-inflammatory cytokines by co-cultures compared to monocultures exposed or not to Stx2, SubAB, and Stx2+SubAB. Under basal conditions, IL-6, IL-8 and TNF-α secretion was different between monocultures and co-cultures. After toxin treatments, high concentrations of Stx2 and SubAB decreased cytokine secretion by HGEC monocultures, but in contrast, low toxin concentrations increased their release. Toxins did not modulate the cytokine secretion by HK-2 monocultures, but increased their release in the HK-2 co-culture compartment. In addition, HK-2 monocultures were stimulated to release IL-8 after incubation with HGEC conditioned media. Finally, Stx2 and SubAB were detected in HGEC and HK-2 cells from the co-cultures. This work describes, for the first time, the inflammatory responses induced by Stx2 and SubAB, in a crosstalk model of renal endothelial and epithelial cells.

[Complement-mediated hemolytic uremic syndrome: a diagnostic approach]

Complement-mediated hemolytic uremic syndrome (a-HUS), an uncommon variant of thrombotic microangiopathy, is characterized by hemolytic anemia, thrombocytopenia and renal impairment. This disorder might be inherited or/and acquired and leads to dysregulation of the alternative complement pathway at the endothelial cell surface and formation of microvascular thrombi. The differential diagnosis includes other forms of hemolytic syndrome (eg. Shiga-toxin-producing E.coli or S. dysenteriae -associated HUS - STEC-HUS), thrombotic thrombocytopenic purpura (TTP) and congenital errors of vitamin B12 metabolism. The diagnostic approach is presented below.

ASSESSMENT OF THE LEVEL OF KNOWLEDGE OF MEDICAL PERSONNEL IN DIARRHEA AND HEMOLYTIC-UREMIC SYNDROME

Survey have been conducted among medical professionals to test knowledge level of HUS and diarrheal diseases and to identify predictor variables for better knowledge. Cross-sectional survey have been conducted among medical personnel at different clinics in Tbilisi and in regions of Georgia. Participants were selected from different clinics in Tbilisi and in three biggest regional cities (Zugdidi, Batumi and Kutaisi) of Georgia. A total of 12 clinics were selected from them 6 were in Tbilisi and 2 at each regional cities. Clinics were selected based on their ability to provide services for gastrointestinal diseases, infectious diseases and kidney diseases. Data were entered into electronic database and analyzed using R v3.3.2. Descriptive statistics and methods of multivariate analysis were used for data analysis. 366 medical personnel have been interviewed. 73% (267) were females and 27% (99) males. Mean age was 40.8, IQR (27-52). A total of 64% (235) participants were from clinics located in Tbilisi. In multivariate analysis background in infectious diseases, female sex and having more than 10 years of medical experience were significantly associated with the total knowledge score of diarrheal diseases (p<0.05). High total knowledge score of HUS was detected among pediatricians (p<0.05). Trainings has been recommended for medical specialists to increase knowledge of diarrheal diseases and HUS to be able to identify those condition and to provide timely medical support for patients.

Colonic ischaemia as a severe Shiga toxin/verotoxin producing Escherichia coli O104:H4 complication in a patient without haemolytic uraemic syndrome, Germany, June 2011

An increasing rate of infections with Shiga toxin/verotoxin-producing Escherichia coli (STEC/VTEC) O104:H4 has been observed in Germany since May 2011, with unusually high numbers of patients suffering from haemolytic uraemic syndrome (HUS). We report a STEC/VTEC O104:H4 case without HUS, presenting with colonic ischaemia demanding surgery. This atypical clinical presentation of STEC O104:H4 infection might indicate new severe complications associated with this uncommon strain, and highlights the importance of immediate interdisciplinary assessment of STEC/VTEC patients.

Hemolytic uremic syndrome

CONTEXT

Hemolytic uremic syndrome (HUS) is a severe acute disease, sometimes with long-term sequelae. The diarrhoea-unrelated forms are particularly associated with a poor prognosis. The aim of this paper is to review current evidence regarding etiology and management, and explore methods by which the outcome may be optimized.

EVIDENCE ACQUISITION

An internet search of Medline, Medscape, MDConsult and Cochrane databases for publications related to HUS from 1998 onwards was performed. A review of articles pertaining to etiopathogenesis and management was undertaken.

RESULTS

HUS is now classified according to cause. New assays and gene studies allow exact diagnosis of many of the atypical forms. Post-exposure prevention of diarrhoea associated HUS with vaccines and toxin-binding agents, remains in the experimental stages. Specific directed therapies aimed at replacing deficient factors can improve the outcome of atypical HUS.

CONCLUSIONS

Supportive care remains the cornerstone of management of HUS. The infection-unrelated forms should in addition be treated rapidly with plasma therapy. Efforts should be made to make an exact etiological diagnosis in all patients, as long-term treatment and prognosis is affected. Prevention of diarrhea-associated HUS by improving sanitation and proper attention to food hygiene is a practical goal.

Risk factors of acute renal failure in critically ill children: A prospective descriptive epidemiological study

OBJECTIVE

Acute renal failure is a serious condition in critically ill patients, but little literature is available on acute renal failure in critically ill children. The aim of the study was to determine incidence rate, identify risk factors, and describe the clinical outcome of acute renal failure in the pediatric intensive care unit (PICU).

DESIGN

Prospective, descriptive study.

SETTING

A tertiary PICU.

PATIENTS

Patients were 1,047 consecutively admitted children over a 1-yr period.

INTERVENTIONS

None.

MEASUREMENTS AND MAIN RESULTS

Acute renal failure was defined as doubling of baseline serum creatinine. A comparison between patients with acute renal failure and without acute renal failure was carried out, and the risk factors playing a significant role in the manifestation of acute renal failure were analyzed. There were 985 cases included in the study, with the incidence rate of acute renal failure in PICU being 4.5%. The most common PICU admission diagnoses in acute renal failure cases were hemolytic uremic syndrome (18.2%), oncologic pathologies (18.2%), and cardiac surgery (11.4%). Significant risk factors for acute renal failure following multivariate analysis were thrombocytopenia (odds ratio, 6.3; 95% confidence interval, 2.5, 16.2), age >12 yrs (odds ratio, 4.9; 95% confidence interval, 1.9, 13), hypoxemia (odds ratio, 3.2; 95% confidence interval, 1.3, 8.0), hypotension (odds ratio, 3.0; 95% confidence interval, 1.2, 7.5), and coagulopathy (odds ratio, 2.7; 95% confidence interval, 1.3, 5.6). The mortality rate was estimated to be higher in patients with acute renal failure compared with patients without acute renal failure (29.6% vs. 2.3%, p < .001).

CONCLUSIONS

Although not frequent in the PICU, acute renal failure is associated with a significant increase in mortality. The risk factors of acute renal failure are multiple and are often present before PICU admission. A multiple-center study is planned with the intention to confirm these results.

A Bayesian approach to acute infectious diarrhea in adults

Acute infectious diarrhea is a yearly occurrence for most Americans, and is associated with 1 million hospitalizations and about 6000 deaths in the United States annually. Up to 80% of acute infectious diarrhea is caused by noroviruses, which produce a clinically mild illness with a predictable short course and good outcome that make laboratory testing and antimicrobial treatment unnecessary. Most diarrhea-causing bacteria and protozoa can cause a clinical illness "like norovirus"; when they do so in healthy adults neither specialized testing nor antimicrobials is required. The presence or absence of epidemiologic evidence (such as travel, hospitalization, antibiotic use, other exposures)and clinical evidence (such as diarrhea frequency and duration, severity of abdominal pain and fever, character of stool, presence of chronic illness or immune deficiency) can change the probability of "not norovirus" from as low as 8% to as high as 100%. Such probabilities guide the use of laboratory testing and antimicrobial therapy in patients who have acute infectious diarrhea.

Severe secondary deficiency of von Willebrand factor-cleaving protease (ADAMTS13) in patients with sepsis-induced disseminated intravascular coagulation: its correlation with development of renal failure

Deficiency of ADAMTS13 is found in patients with thrombotic thrombocytopenic purpura (TTP), and the genetic defects in the ADAMTS13 gene or the autoantibody against ADAMTS13 is thought to be responsible for the development of TTP. The clinical correlation and mechanisms of secondary ADAMTS13 deficiency in other disease states were investigated. In addition to TTP, ADAMTS13 levels were severely decreased in patients with sepsis-induced disseminated intravascular coagulation (DIC). The incidence of acute renal failure and serum creatinine levels in patients with ADAMTS13 activity levels lower than 20% (incidence, 41.2%; creatinine, 160 +/- 150 microM [1.81 +/- 1.70 mg/dL]) (P < .05) were significantly higher than they were in patients with ADAMTS13 activity levels higher than 20% (incidence, 15.4%; creatinine, 84 +/- 67 microM [0.95 +/- 0.76 mg/dL]) (P < .01). Additionally, unusually large von Willebrand factor multimers were detected in 26 (51.0%) of 51 patients with ADAMTS13 activity levels lower than 20%. Lower molecular weight forms of ADAMTS13 were found in the plasma of patients with sepsis-induced DIC, suggesting that the deficiency of ADAMTS13 was partially caused by its cleavage by proteases in addition to decreased synthesis in the liver. These data suggested that severe secondary ADAMTS13 deficiency can be associated with sepsis-induced DIC and may contribute to the development of renal failure.

Recurrent glomerulonephritis in the renal allograft: an update of selected areas

Glomerular diseases, including diabetes and various forms of glomerulonephritis, account for more than 70% of patients undergoing renal transplantation. Among these patients, more than 40% develop significant proteinuria, and around 15% develop persistent nephrotic syndrome. The most common cause of posttransplantation proteinuria is chronic allograft nephropathy (60%), followed by recurrent (15%) and de novo (10%) glomerulonephritis. Persistent proteinuria is associated with a significantly reduced rate of graft survival but often can be controlled with non-disease-specific therapy including angiotensin-converting enzyme inhibitors and angiotensin receptor blockers with favorable effects on long-term prognosis. Recurrent or de novo glomerulonephritis occurs in 6%-20% of patients overall and is more common in patients transplanted with glomerulonephritic organs. Glomerulonephritis in the allograft is also associated with a reduction in long-term (5-year) graft survival (40% vs 70%). The most common diseases associated with allograft glomerulonephritis and their recurrence rates in transplantation patients are idiopathic focal glomerular sclerosis (20%-30%), IgA nephropathy (25%), membranoproliferative glomerulonephritis (type 1, 25%; type 2, 80%), membranous nephropathy (30%), and hemolytic-uremic syndrome (classic, 10%; atypical, 40%; familial, 60%). This article reviews new developments in the understanding of 3 of these diseases-focal glomerular sclerosis, membranous nephropathy, and hemolytic-uremic syndrome-as they relate to the incidence of recurrence, the effects of recurrence on graft survival, risk factors for recurrence, and management issues for nephrologists caring for patients with renal allografts. Proper donor selection, early diagnosis in high-risk patients, and appropriate management can prolong graft survival and improve long-term outcomes.

Persistant pre-eclampsia post partum with elevated liver enzymes and hemolytic uremic syndrome

The spectrum of complications with pre-eclampsia, which may include AFLP (acute fatty liver of pregnancy) as well as the HELLP syndrome (hemolysis, elevated liver enzymes, and low platelets), is resolved by early delivery. However, the ravages of HUS/TTP (hemolytic uremic syndrome/thrombotic thrombocytopenic purpura) require therapy usually by plasma exchange. Overlap between these two groups of syndromes has occurred on rare occasions and usually requires the therapy of the predominant or more dangerous or threatening form. Such overlap can be appreciated and then treated successfully without residual morbidity. The index case is presented and an extensive review of the two groups of syndromes is provided.

A case of hemolytic uremic syndrome associated with emphysematous cholecystitis and a liver abscess

Hemolytic uremic syndrome (HUS) is characterized by microangiopathic hemolytic anemia, thrombocytopenia and acute renal failure. Most cases of HUS are characterized by a prodromal phase of diarrhea and melena, and affect mainly children. Here we report a unique case of adult-onset HUS that was associated with emphysematous cholecystitis and a liver abscess. The patient did not suffer from diarrhea or melena on admission, but abdominal CT scans revealed emphysematous cholecystitis and a liver abscess. Cholecystectomy was performed and the liver abscess was drained. Cultures of the bile and liver abscess contents were negative, but the serum samples had antibodies against Escherichia coli (E. coli) O157. The patient was anuric for 14 days, and underwent hemodialysis that was repeated 15 times and plasma exchanges 6 times. She recovered from acute renal failure but with inadequate urinary concentrating ability as a sequela. Histopathological examination of renal biopsy specimens on the 83rd hospital day revealed almost normal glomeruli and patchy atrophy of tubules with an increase of interstitium. This is a very rare case of HUS associated with emphysematous cholecystitis and a liver abscess successfully treated with aggressive supportive care. It is possible that an infection with verotoxin-producing E. coli O157 caused the disease.

Renal manifestations of systemic diseases

During childhood, the kidney may be involved in several different systemic diseases including the vasculitic syndromes, collagen vascular diseases, and the thrombotic microangiopathic diseases. This article discusses three of the more common systemic disease including Henoch Schonlein Purpura (HSP), systemic lupus erythematosus (SLE), and the hemolytic uremic syndrome (HUS), which occur during childhood. Each of these diseases have important renal manifestations that may present with hematuria with or without proteinuria, hypertension, rapidly progressive glomerulonephritis, and/or with acute renal failure. The occurrence of these diseases during childhood raises lifelong concerns for the child's renal function. As in glomerulonephritis associated with SLE, reactivation of the underlying disease can result in additional renal injury, whereas late extrarenal and renal complications may be observed following HUS or nephritis associated with HSP. These diseases are not only an important cause of acquired chronic renal failure during childhood, but may also lead to end-stage renal disease or other complications that do not become apparent until adulthood. In each disease, we will review the clinical manifestations, the pathology, pathophysiology, and current management and therapy.

Plasma therapy at Klinikum Grosshadern: a 15-year retrospective

Immediately after the availability of highly permeable membranes in 1979, membrane plasma separation was introduced as a mode of extracorporeal blood purification by the nephrology group at Klinikum Grosshadern of the Ludwig Maximilians University of Munich (F.R.G.). The new therapy was applied primarily in the management of immunologically mediated renal and extrarenal disorders as well as in paraproteinemias. We also have witnessed a widespread application of this extracorporeal treatment as a last resort in otherwise refractory clinical conditions. Over the years, the group at Grosshadern has contributed to the development, as well as to the laboratory and clinical testing, of new plasma separation membranes, simplified plasmapheresis formats (e.g., spontaneous membrane plasma separation), and several plasma fractionation procedures (e.g., cascade filtration, adsorption). Whenever indicated and possible, plasma fractionation procedures, rather than unselective plasma exchange, are performed in an appropriate clinical situation.

Neurological manifestations of hemorrhagic colitis in the outbreak of Escherichia coli O157:H7 infection in Japan

An outbreak of hemorrhagic colitis associated with Escherichia coli O157:H7 occurred in a kindergarten in Saitama, Japan from September to November, 1990. Seven patients admitted to our hospital showed neurological manifestations: generalized seizures, impaired consciousness, urinary incontinence, gaze nystagmus, phrenic nerve palsy, action tremor and vertigo. Two patients died. On the basis of the clinical courses and laboratory findings of the seven patients and postmortem findings of one case, these neurological symptoms were suspected to be induced by the verotoxin elaborated by Escherichia coli O157:H7.

Renal disease in pregnancy

Renal disease in pregnancy may be progressive but only rarely. The problems encountered that create maternal and fetal morbidity and mortality relate to the development of superimposed preeclampsia and renal failure. Diagnosis is important to differentiate the cause of renal pathology so that appropriate treatment can be undertaken. The use of medications in renal disease in the presence of hypertension is controversial; however, adequate therapy should be given if indicated. Most cases of renal disease in pregnancy do not require termination; however, counseling concerning pregnancy is needed initially or subsequently.