Predictors for the development of haemolytic uraemic syndrome with Escherichia coli O157:H7 infections: with focus on the day of illness

Haemolytic uraemic syndrome in children England, Wales, Northern Ireland, and Ireland: A prospective cohort study

Haemolytic uraemic syndrome (HUS) caused by infection with Shiga toxin-producing Escherichia coli (STEC) is a relatively rare but potentially fatal multisystem syndrome clinically characterised by acute kidney injury. This study aimed to provide robust estimates of paediatric HUS incidence in England, Wales, Northern Ireland, and the Republic of Ireland by using data linkage and case reconciliation with existing surveillance systems, and to describe the characteristics of the condition. Between 2011 and 2014, 288 HUS patients were included in the study, of which 256 (89.5%) were diagnosed as typical HUS. The crude incidence of paediatric typical HUS was 0.78 per 100,000 person-years, although this varied by country, age, gender, and ethnicity. The majority of typical HUS cases were 1 to 4 years old (53.7%) and female (54.0%). Clinical symptoms included diarrhoea (96.5%) and/or bloody diarrhoea (71.9%), abdominal pain (68.4%), and fever (41.4%). Where STEC was isolated (59.3%), 92.8% of strains were STEC O157 and 7.2% were STEC O26. Comparison of the HUS case ascertainment to existing STEC surveillance data indicated an additional 166 HUS cases were captured during this study, highlighting the limitations of the current surveillance system for STEC for monitoring the clinical burden of STEC and capturing HUS cases.

A practical composite risk score for the development of Haemolytic Uraemic Syndrome from Shiga toxin-producing Escherichia coli

BACKGROUND

Haemolytic Uraemic Syndrome (HUS) is a serious complication of Shiga toxin-producing Escherichia coli (STEC) infection and the key reason why intensive health protection against STEC is required. However, although many potential risk factors have been identified, accurate estimation of risk of HUS from STEC remains challenging. Therefore, we aimed to develop a practical composite score to promptly estimate the risk of developing HUS from STEC.

METHODS

This was a retrospective cohort study where data for all confirmed STEC infections in Ireland during 2013-15 were subjected to statistical analysis with respect to predicting HUS. Multivariable logistic regression was used to develop a composite risk score, segregating risk of HUS into 'very low risk' (0-0.4%), 'low risk' (0.5-0.9%), 'medium risk' (1.0-4.4%), 'high risk' (4.5-9.9%) and 'very high risk' (10.0% and over).

RESULTS

There were 1397 STEC notifications with complete information regarding HUS, of whom 5.1% developed HUS. Young age, vomiting, bloody diarrhoea, Shiga toxin 2, infection during April to November, and infection in Eastern and North-Eastern regions of Ireland, were all statistically significant independent predictors of HUS. Demonstration of a risk gradient provided internal validity to the risk score: 0.2% in the cohort with 'very low risk' (1/430), 1.1% with 'low risk' (2/182), 2.3% with 'medium risk' (8/345), 3.1% with 'high risk' (3/98) and 22.2% with 'very high risk' (43/194) scores, respectively, developed HUS.

CONCLUSION

We have developed a composite risk score which may be of practical value, once externally validated, in prompt estimation of risk of HUS from STEC infection.

Shiga Toxin-Associated Hemolytic Uremic Syndrome: A Narrative Review

The severity of human infection by one of the many Shiga toxin-producing Escherichia coli (STEC) is determined by a number of factors: the bacterial genome, the capacity of human societies to prevent foodborne epidemics, the medical condition of infected patients (in particular their hydration status, often compromised by severe diarrhea), and by our capacity to devise new therapeutic approaches, most specifically to combat the bacterial virulence factors, as opposed to our current strategies that essentially aim to palliate organ deficiencies. The last major outbreak in 2011 in Germany, which killed more than 50 people in Europe, was evidence that an effective treatment was still lacking. Herein, we review the current knowledge of STEC virulence, how societies organize the prevention of human disease, and how physicians treat (and, hopefully, will treat) its potentially fatal complications. In particular, we focus on STEC-induced hemolytic and uremic syndrome (HUS), where the intrusion of toxins inside endothelial cells results in massive cell death, activation of the coagulation within capillaries, and eventually organ failure.

Postinfectious Hemolytic Uremic Syndrome

Post-infectious hemolytic uremic syndrome (HUS) is caused by specific pathogens in patients with no identifiable HUS-associated genetic mutation or autoantibody. The majority of episodes is due to infections by Shiga toxin (Stx) producing Escherichia coli (STEC). This chapter reviews the epidemiology and pathogenesis of STEC-HUS, including bacterial-derived factors and host responses. STEC disease is characterized by hematological (microangiopathic hemolytic anemia), renal (acute kidney injury) and extrarenal organ involvement. Clinicians should always strive for an etiological diagnosis through the microbiological or molecular identification of Stx-producing bacteria and Stx or, if negative, serological assays. Treatment of STEC-HUS is supportive; more investigations are needed to evaluate the efficacy of putative preventive and therapeutic measures, such as non-phage-inducing antibiotics, volume expansion and anti-complement agents. The outcome of STEC-HUS is generally favorable, but chronic kidney disease, permanent extrarenal, mainly cerebral complication and death (in less than 5 %) occur and long-term follow-up is recommended. The remainder of this chapter highlights rarer forms of (post-infectious) HUS due to S. dysenteriae, S. pneumoniae, influenza A and HIV and discusses potential interactions between these pathogens and the complement system.

Risk of haemolytic uraemic syndrome caused by shiga-toxin-producing Escherichia coli infection in adult women in Japan

Shiga-toxin-producing Escherichia coli (STEC) infections usually cause haemolytic uraemic syndrome (HUS) equally in male and female children. This study investigated the localization of globotriaosylceramide (Gb3) in human brain and kidney tissues removed from forensic autopsy cases in Japan. A fatal case was used as a positive control in an outbreak of diarrhoeal disease caused by STEC O157:H7 in a kindergarten in Urawa in 1990. Positive immunodetection of Gb3 was significantly more frequent in female than in male distal and collecting renal tubules. To correlate this finding with a clinical outcome, a retrospective analysis of the predictors of renal failure in the 162 patients of two outbreaks in Japan was performed: one in Tochigi in 2002 and the other in Kagawa Prefecture in 2005. This study concludes renal failure, including HUS, was significantly associated with female sex, and the odds ratio was 4·06 compared to male patients in the two outbreaks. From 2006 to 2009 in Japan, the risk factor of HUS associated with STEC infection was analysed. The number of males and females and the proportion of females who developed HUS were calculated by age and year from 2006 to 2009. In 2006, 2007 and 2009 in adults aged >20 years, adult women were significantly more at risk of developing HUS in Japan.

Shiga toxin-2 enhances heat-shock-induced apoptotic cell death in cultured and primary glial cells

The blood-brain barrier (BBB) selectively controls the homeostasis of the central nervous system (CNS) environment using specific structural and biochemical features of the endothelial cells, pericytes, and glial limitans. Glial cells, which represent the cellular components of the mature BBB, are the most numerous cells in the brain and are indispensable for neuronal functioning. We investigated the effects of Shiga toxin on glial cells in vitro. Shiga toxin failed to inhibit cell proliferation but attenuated expression of heat shock protein 70, which is one of the chaperone proteins, in cultured and primary glial cells. Furthermore, the combination of Shiga toxin and a heat shock procedure induced cell apoptosis and decreased cell proliferation in both cells. Thus, we speculate that glial cell death in response to the combination of Shiga toxin and heat shock might weaken the BBB and induce central nervous system complications.

Management of hemolytic-uremic syndrome in children

Acute renal failure associated with a fulminant, life-threatening systemic disease is rare in previously healthy young children; however, when it occurs, the most common cause is hemolytic-uremic syndrome (HUS). In most cases (90%), this abrupt and devastating illness is a result of ingestion of food or drink contaminated with pathogens that produce very potent toxins. Currently, there are no proven treatment options that can directly inactivate the toxin or effectively interfere with the cascade of destructive events triggered by the toxin once it gains access to the bloodstream and binds its receptor. However, HUS is self-limited, and effective supportive management during the acute phase is proven to be a life saver for children affected by HUS. A minority of childhood HUS cases, approximately 5%, are caused by various genetic mutations causing uncontrolled activation of the complement system. These children, who used to have a poor prognosis leading to end-stage renal disease, now have access to exciting new treatment options that can preserve kidney function and avoid disease recurrences. This review provides a summary of the current knowledge on the epidemiology, pathophysiology, and clinical presentation of childhood HUS, focusing on a practical approach to best management measures.

Chronic sequelae of E. coli O157: systematic review and meta-analysis of the proportion of E. coli O157 cases that develop chronic sequelae

OBJECTIVE

This was a systematic review and meta-analysis to determine the proportion of Escherichia coli O157 cases that develop chronic sequelae.

DATA SOURCES

We conducted a systematic review of articles published prior to July 2011 in Pubmed, Agricola, CabDirect, or Food Safety and Technology Abstracts.

STUDY SELECTION

Studies were selected that reported the number of E. coli O157 cases that developed reactive arthritis (ReA), hemolytic uremic syndrome (HUS), irritable bowel syndrome, inflammatory bowel disease, or Guillain Barré syndrome.

METHODS

Three levels of screening and data extraction of articles were conducted using predefined data fields. Meta-analysis was performed on unique outcome measures using a random-effects model, and heterogeneity was assessed using the I² value. Meta-regression was used to explore the influence of nine study-level variables on heterogeneity.

RESULTS

A total of 82 studies were identified reporting 141 different outcome measures; 81 reported on HUS and one reported on ReA. Depending on the number of cases of E. coli O157, the estimate for the proportion of E. coli O157 cases that develop HUS ranged from 17.2% in extra-small studies (<50 cases) to 4.2% in extra-large studies (>1000 cases). Heterogeneity was significantly associated with group size (p<0.0001); however, the majority of the heterogeneity was unexplained.

CONCLUSIONS

High unexplained heterogeneity indicated that the study-level factors examined had a minimal influence on the variation of estimates reported.

An epidemiologic surveillance of Shiga-like toxin-producing Escherichia coli infection in Argentinean children: risk factors and serum Shiga-like toxin 2 values

BACKGROUND AND AIMS

Shiga-like toxin (Stx)-producing Escherichia coli (STEC) infection is an ongoing health issue that can lead to serious complications, including hemolytic uremic syndrome (HUS) and death. This study assessed demographic and epidemiologic information of STEC infection among Argentinean children.

METHODS

A prospective surveillance of 2435 screened children (age, 0.5-15 years) presenting with watery diarrhea and/or bloody diarrhea was undertaken to evaluate the clinical course of STEC infection.

RESULTS

Prevalence of STEC infection was 4.1% among subjects presenting with watery diarrhea for ≤ 5 days' duration, bloody diarrhea for ≤ 36 hours' duration, or both. Incidence of STEC infection was significantly higher in the subjects with bloody diarrhea. Ninety-three STEC+ children underwent further evaluation, of whom 8 (8.6%) developed HUS. White blood cells, particularly neutrophils, were abnormally elevated at screening in 5 of 8 HUS subjects. Quantifiable serum Stx-2 values were noted within 24 to 48 hours after the onset of bloody diarrhea in 3 HUS subjects using a validated chemiluminescence assay, with levels quickly dissipating by HUS onset.

CONCLUSIONS

Results suggest that young STEC-positive children with bloody diarrhea and exhibiting neutrophilic leukocytosis in the early course of their diarrhea are at risk for HUS progression. The observation of measurable concentrations of Stx-2 levels in the early post-bloody-diarrhea period and rapid dissipation at the time of HUS onset requires further evaluation.

Differential virulence of clinical and bovine-biased enterohemorrhagic Escherichia coli O157:H7 genotypes in piglet and Dutch belted rabbit models

Enterohemorrhagic Escherichia coli O157:H7 (EHEC O157) is an important cause of food and waterborne illness in the developed countries. Cattle are a reservoir host of EHEC O157 and a major source of human exposure through contaminated meat products. Shiga toxins (Stxs) are an important pathogenicity trait of EHEC O157. The insertion sites of the Stx-encoding bacteriophages differentiate EHEC O157 isolates into genogroups commonly isolated from cattle but rarely from sick humans (bovine-biased genotypes [BBG]) and those commonly isolated from both cattle and human patients (clinical genotypes [CG]). Since BBG and CG share the cardinal virulence factors of EHEC O157 and are carried by cattle at similar prevalences, the infrequent occurrence of BBG among human disease isolates suggests that they may be less virulent than CG. We compared the virulence potentials of human and bovine isolates of CG and BBG in newborn conventional pig and weaned Dutch Belted rabbit models. CG-challenged piglets experienced severe disease accompanied by early and high mortality compared to BBG-challenged piglets. Similarly, CG-challenged rabbits were likely to develop lesions in kidney and intestine compared with the BBG-challenged rabbits. The CG strains used in this study carried stx2 and produced significantly higher amounts of Stx, whereas the BBG strains carried the stx2c gene variant only. These results suggest that BBG are less virulent than CG and that this difference in virulence potential is associated with the Stx2 subtype(s) carried and/or the amount of Stx produced.

Gene cluster conferring streptomycin, sulfonamide, and tetracycline resistance in Escherichia coli O157:H7 phage types 23, 45, and 67

Multidrug resistance to streptomycin, sulfonamide, and tetracycline (AMR-SSuT) was identified in 156 of 171 isolates of Escherichia coli O157:H7 of phage types 23, 45, and 67. In 154 AMR-SSuT isolates, resistance was encoded by strA, strB, sul2, and tet(B), which in 59 of 63 tested isolates were found clustered together on the chromosome within the cdiA locus.

Hemolytic-uremic syndrome in Switzerland: a nationwide surveillance 1997-2003

Hemolytic-uremic syndrome (HUS) is a leading cause of acute renal failure in childhood. In its typical presentation, it is preceded by an episode of diarrhea mostly due to Shiga-toxin-producing Escherichia coli. There is important geographical variation of many aspects of this syndrome. Nationwide data on childhood HUS in Switzerland have not been available so far. In a prospective national study through the Swiss Pediatric Surveillance Unit 114 cases (median age 21 months, 50% boys) were reported between April 1997 and March 2003 by 38 pediatric units (annual incidence 1.42 per 10(5) children < or =16 years). Shiga-toxin-producing E. coli were isolated in 32 (60%) of tested stool samples, serotype O157:H7 in eight. Sixteen children presented with only minimal renal involvement, including three with underlying urinary tract infection. Six patients presented with atypical hemolytic-uremic syndrome, and six with HUS due to invasive Streptococcus pneumoniae infection. Mortality was 5.3%, including two out of six children with S. pneumoniae infection. The severity of thrombocytopenia and the presence of central nervous system involvement significantly correlated with mortality. In conclusion, childhood HUS is not rare in Switzerland. Contrasting other countries, E. coli O157:H7 play only a minor role in the etiology. Incomplete manifestation is not uncommon.

Hemolytic uremic syndrome risk and Escherichia coli O157:H7

We reviewed medical records of 238 hospitalized patients with Escherichia coli O157:H7 diarrhea to identify risk factors for progression to diarrhea-associated hemolytic uremic syndrome (HUS). Data indicated that young age, long duration of diarrhea, elevated leukocyte count, and proteinuria were associated with HUS.

The relationship between self-reported difficulty with hearing in the worse ear and the better ear

OBJECTIVES

To investigate the relationship of self-reported hearing difficulty with hearing in the worse ear and the better ear at 1 and 4 kHz.

DESIGN

Receiver-operating characteristic (ROC) curve analysis in community-residing population.

SETTINGS

The Settsu City Health Center (Osaka, Japan).

PARTICIPANTS

A total of 919 consecutive participants who were provided health check-ups.

MAIN OUTCOMES MEASURES

Comparison is based on the measurement of the area under the curve (AUC) of ROC.

RESULTS

At 1 kHz, the area under the curve (AUC) of the worse ear (0.625 +/- 0.021) was significantly larger than that of the better ear (0.570 +/- 0.021) (P < 0.01). At 4 kHz, the AUC of the worse ear (0.665 +/- 0.019) was significantly larger than that of the better ear (0.622 +/- 0.020) (P < 0.01). Excluding the subjects with noise exposure, tinnitus and ear disease, at both frequencies, the AUC of the worse ear was not significantly larger than that of the better ear at both 1 and 4 kHz. Hearing in the worse ear was significantly more related to self-reported hearing difficulty than in the better ear without excluding those with noise exposure, tinnitus and ear disease.

CONCLUSIONS

ROC curve analysis would provide a method to help us judge the difference between the worse hearing ear and the better hearing ear on the subject of hearing loss.

Not All Inflammation in the Right Lower Quadrant is Appendicitis: A Case Report of Escherichia coli O157:H7 with a Review of the Literature

Although significant work has been presented on this subject in pediatric, infectious disease, and epidemiologic literature, there is a noteworthy lack of information on Escherichia coli O157:H7 in any surgical journals. As this disease can present with signs and symptoms often ascribed to the acute abdomen, it is imperative that the general surgeon, pediatric surgeon, and colorectal surgeon are all familiar with this infection and its clinical ramifications. A case report followed by a review of the literature is presented.

Hemolytic uremic syndrome incidence in New York

A comparison of New York’s traditional communicable disease surveillance system for diarrhea-associated hemolytic uremic syndrome with hospital discharge data showed a sensitivity of 65%. Escherichia coli O157:H7 was found in 63% of samples cultured from hemolytic uremic syndrome patients, and samples were more likely to be positive when collected early in illness.

Epidemiology and spectrum of disease of Escherichia coli O157

PURPOSE OF REVIEW

The Shiga toxin-producing Escherichia coli strains, such as E. coli O157:H7, have emerged as major diarrheal pathogens both in the United States and elsewhere. These organisms are important because gastrointestinal infection (afebrile hemorrhagic colitis) can trigger microangiopathic hemolytic anemia and renal failure (hemolytic uremic syndrome). Understanding the pathophysiology of this illness is likely to lead to important new treatment interventions.

RECENT FINDINGS

It is now recognized that children with hemorrhagic colitis routinely develop a spectrum of coagulation abnormalities and that only a fraction of children develop full blown hemolytic uremic syndrome. Individual variability in expression of inflammatory mediators is likely to be a key element in determining which children progress to the severe end of the spectrum of disease. The value of antibiotic therapy is unknown.

SUMMARY

The pathophysiology of HUS remains incompletely understood. The lag between onset of diarrhea and onset of HUS represents an opportunity to intervene and prevent renal failure. However, there currently is no way to prevent such life threatening complications. The management should focus on diagnosis and close observation so that early intervention can prevent complications.

A simple clinical and paraclinical score predictive of CD4 cells counts below 400/mm3 in HIV-infected adults in Dakar University Hospital, Senegal

In industrialized countries the decision to start co-trimoxazole (CMX) prophylaxis of HIV-related opportunistic infections is based on the CD4+ cell count. The value of CMX prophylaxis has also been demonstrated in Africa, where CD4+ cell counts are rarely available. We therefore developed a simple score predictive of a threshold CD4+ cell count (400/mm3) below which CMX prophylaxis is indicated. In a retrospective cross-sectional study, we collected clinical and biological data on 211 HIV-infected patients recruited from January 1996 through January 1998 at Fann University Hospital in Dakar, Senegal. Several variables were identified as being predictive of a CD4+ cell count below 400/mm3 by stepwise logistic regression. Each variable was weighted according to its regression coefficient, as follows: male sex (+1), weight loss (+2), body mass index < 22 (+2), herpes zoster (+4), tuberculin induration < 5 mm (+3) and haemoglobin < or = 10 g/dL (+1). A score of > or = 4 (sum of weights) selected patients with CD4+ cell counts below 400/mm3 with a sensitivity of 98% and a negative predictive value of 83%. Such a score should be applicable in the African context and should facilitate the management of HIV-infected patients, especially the prescription of CMX prophylaxis.

New aspects in the pathogenesis and treatment of thrombotic thrombocytopenic purpura and hemolytic uremic syndrome

The thrombotic microangiopathy (TM) syndromes, thrombotic thrombocytopenic purpura and the hemolytic uremic syndrome, are a rare and heterogeneous group of disorders characterized by widespread microvascular thrombosis and end organ injury. Decades of descriptive studies have defined clinical subsets of TM syndromes by clinical and laboratory features. Despite many advances, however, progress towards understanding of the etiology and pathogenesis of TM disorders remains limited. The rarity of occurrence and lack of natural animal models of TM syndromes have hampered progress in experimental and clinical studies. Treatment remains essentially empirical and options are limited. However, recent advances in the genetic and molecular understanding of subsets of TM disorders and the development of relevant animal models offer new resources to explore the pathogenic mechanisms. With these new advances more effective and individualized treatments for TM syndromes can be developed.