This case describes evidence for a Shiga toxin-producing Escherichia coli (STEC) O146:H28 infection leading to hemolytic uremic syndrome in a neonate. STEC O146:H28 was linked hitherto with asymptomatic carriage in humans. Based on strain characteristics and genotyping data, the mother is a healthy carrier who transmitted the STEC during delivery. STEC strains belonging to the low-pathogenic STEC group must also be considered in the workup of neonatal hemolytic uremic syndrom

Bucher, Barbara S.

Hächler, Herbert

Kottanattu, Lisa

Simonetti, Giacomo D.

Steinmann, Markus

Stephan, Roger

Stritt, Andrea

Tschumi, Sibylle

von Steiger, Niklaus

RERO DOC Digital Library

B R I E F R E P O R TNeonatal Hemolytic UremicSyndrome After Mother-to-ChildTransmission of a Low-Pathogenicstx2b Harboring Shiga Toxin–Producing Escherichia coliAndrea Stritt,1,a Sibylle Tschumi,1,2,a Lisa Kottanattu,1 Barbara S. Bucher,1Markus Steinmann,1 Niklaus von Steiger,3 Roger Stephan,4Herbert Hächler,4 and Giacomo D. Simonetti11University Children’s Hospital, Inselspital and University of Bern, Switzerland;2Division of Nephrology, The Hospital for Sick Children, University of Toronto,Ontario, Canada; 3Institute for Infectious Diseases, University of Bern, and4Institute for Food Safety and Hygiene, National Centre for EnteropathogenicBacteria and Listeria, University of Zürich, SwitzerlandThis case describes evidence for a Shiga toxin–producingEscherichia coli (STEC) O146:H28 infection leading to he-molytic uremic syndrome in a neonate. STEC O146:H28was linked hitherto with asymptomatic carriage in humans.Based on strain characteristics and genotyping data, themother is a healthy carrier who transmitted the STEC duringdelivery. STEC strains belonging to the low-pathogenicSTEC group must also be considered in the workup of neo-natal hemolytic uremic syndrome.Keywords. hemolytic uremic syndrome; newborn; neona-tal; Shiga-toxin producing Escherichia coli; STEC.The hemolytic uremic syndrome (HUS) is a rare and severethrombotic microangiopathy (TMA) characterized by thetriad of hemolytic anemia, thrombocytopenia, and acute renalfailure. In >90% of cases, the disease is triggered by an infec-tion with Shiga toxin–producing Escherichia coli (STEC) har-boring speciﬁc Shiga toxin (Stx) 2 subtypes and the adhesionfactor intimin and often presents with a prodromal bloody di-arrhea. In particular, children between 2 and 6 years of ageare sensitive to the development of the disease. This HUS iscalled typical HUS or STEC-HUS [1]. Non-STEC-HUS oratypical HUS (aHUS) is seen in 5%–10% of all HUS cases andcan appear at any age and may be sporadic or familial. Themajority of cases of a HUS are caused by a disorder in com-plement alternative pathway regulation and aHUS is oftenused to make referral to this particular subgroup [2].Diagnosis of aHUS relies on (1) no associated disease, (2)no criteria for STEC-HUS, and (3) no criteria for thromboticthrombocytopenic purpura (TTP). Even aHUS and TTPoverlap clinically and morphologically; the discovery of thespeciﬁc involvement of ADAMTS13 (a disintegrin and metal-loproteinase with a thrombospondin type 1 motif, member13) in the pathogenesis of TTP allows discrimination betweenthe 2 TMAs: in patients with TTP, ADAMTS13 activity isgreatly reduced (5%–10% of normal) [3].Neonatal cases of HUS are predominantly related to aHUS(in particular metabolic diseases like cobalamin C disorders);yet, neonatal cases of HUS due to Shiga toxin–producingE. coli have been anecdotally reported [4, 5].We describe the case of a newborn boy presenting with HUSassociated with a low-pathogenic STEC. Genetic analyses of theSTEC strains were able to clarify the route of infection.CASE REPORTA male newborn (weight: 3680 g, 50th centile; length: 52 cm,50th–90th centile; head circumference: 34 cm, 10th centile)was born vaginally by a healthy mother at 41 2/7 weeks ofgestation after a normal pregnancy. Neonatal adaptation wasnormal (Apgar score: 7/9/10) and ﬁrst micturition and meco-nium were unremarkable in the ﬁrst 24 hours of life. Twodays after birth, the newborn displayed relapsing biliary vom-iting in absence of diarrhea or blood-stained stool losses.Ileus, volvulus, and malrotation were ruled out by abdominalradiography and ultrasound. Laboratory investigations did notshow signs of infection or an underlying metabolic disease.Vomiting stopped spontaneously after 48 hours; oral feedingwas restarted and well tolerated.At day 6 of life, a sudden increase of bilirubin (total bilirubin:374 μmol/L, conjugated bilirubin: 42 μmol/L, normal values<4 μmol/L) was observed and phototherapy started. Furtherlaboratory investigations revealed the presence of TMA withhemolytic anemia (hemoglobin, 111 g/L [normal range, 137–205 g/L]; lactate dehydrogenase, 2223 IU/L [normal value,<976 IU/L]; fragmentocytes), thrombocytopenia (39 G/LReceived 11 July 2012; accepted 20 September 2012; electronically published 5 October2012.aA. S. and S. T. contributed equally to this work.Correspondence: Giacomo Simonetti, MD, Pediatric Nephrology, University Children’s Hos-pital, Inselspital, 3010 Bern, Switzerland (giacomo.simonetti@insel.ch).Clinical Infectious Diseases 2013;56(1):114–6© The Author 2012. Published by Oxford University Press on behalf of the Infectious DiseasesSociety of America. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.DOI: 10.1093/cid/cis851114 • CID 2013:56 (1 January) • BRIEF REPORT[normal range, 100–400 G/L]), and acute renal failure (creati-nine, 101 μmol/L [normal value, <78 μmol/L]; urea, 16 mmol/L [normal range, 1.4–6.8 mmol/L]). Urinalysis showed patho-logically increased proteinuria and hematuria, and blood pres-sure was within the normal range. Twenty-four hours later,the newborn developed several episodes of epileptic seizures,which were successfully treated with phenobarbital and topira-mate. Cerebral ultrasound was normal and electroencephalog-raphy registered multifocal epileptogenic activity.Because the newborn did not show any additional deterio-ration of renal function and recovered quickly with normaliza-tion of the hematological and renal parameters together withstable neurological condition without seizures within 48hours, renal replacement therapy, plasma exchange, or themonoclonal antibodies against terminal complement proteinC5 eculizumab were not prescribed.Testing for causes of atypical HUS and TTP (metabolic,complement factors, and ADAMTS13 activity) remained neg-ative. Yet, fecal analysis disclosed the presence of STEC, thuspermitting the diagnosis of typical HUS. Family history wasnegative for renal diseases, parents are not consanguineous,and neither parent had gastrointestinal symptoms during theprevious 3 weeks.At the 11th day of life, the newborn was discharged fromhospital in good general condition and with normal laboratoryﬁndings. Antiepileptic therapy with phenobarbital and topira-mate was tapered during the next 3 months. Within the last 9months of follow-up, hematological and renal parameters re-mained within normal range, and the somatic and neurologi-cal development was unremarkable.MICROBIOLOGICAL ANALYSISStool samples from the boy and the mother were negative forSalmonella, Campylobacter, and Shigella by standard bacteriol-ogy [6] but positive by using an enzyme immunoassay (Pro-SpecT Shiga Toxin E. coli test; Remel, Lenexa, Kansas) as wellas multiplex polymerase chain reaction (PCR) analysis (E. coliDEC Primer Mix, Statens Serum Institut, Copenhagen,Denmark) for STEC.For the isolation of STEC strains, the stool samples werestreaked onto MacConkey agar, and, after incubation at 37°Cfor 24 hours, colonies were washed off with 2 mL of 0.85%saline solution and tested by colony dot-blot hybridization withShiga toxin DNA probes as described by Kaufmann et al [7].One isolate per sample, corresponding to colored spots, waspicked from the hybridization plate, grown at 37°C overnighton sheep blood agar, and conﬁrmed as STEC.Serotyping of the strains was performed with O (O1 toO186) and H (H1 to H56) speciﬁc rabbit antisera produced atthe Federal Institute for Risk Assessment in Germany.Shiga toxin genes were subtyped by PCR according to astandard procedure proposed by the World Health Organiza-tion Collaborating Centre for Reference and Research on Es-cherichia and Klebsiella (http://www.ssi.dk). Genes encodingnon–Shiga toxin putative virulence factors of STEC, includingtoxins, adhesins, and plasmid-located genes (Table 1), weredetected using a DNA microarray (Identibac E. coli Genotyp-ing, Alere, Germany).For genotyping, pulsed-ﬁeld gel electrophoresis (PFGE) wasperformed by following the Centers for Disease Control andPrevention PulseNet protocol using the restriction enzymeXbaI and the CHEF-DR III system (Bio-Rad Laboratories).The pulse times were ramped from 5 seconds to 50 secondsfor 19 hours and an angle of 120°. Salmonella Braenderupstrain H9812 (ATCC BAA 664) was used as reference.RESULTS OF STEC CHARACTERIZATIONThe 2 STEC strains isolated from the neonate (strainN12-0034) and the mother (strain N12-0035) showed asorbitol-fermenting STEC serotype O146:H28 that harboredthe virulence gene stx2, but were negative for eae and hlyA.Selected results for further virulence-associated genes areTable 1. Presence of Selected Non-stx Putative VirulenceGenes Including Toxins, Adhesins, and Plasmid-Located Genesfor the 2 Shiga Toxin–Producing Escherichia coli Strains IsolatedFrom a Newborn Boy (N12-0034) and His Mother (N12-0035)Gene DescriptionN12-0034(Neonate)N12-0035(Mother)EHEC-hlyA EHEC hemolysin − −astA Heat-stableenterotoxin 1+ +cdtB Cytolethaldistending toxin B− −eae Intimin − −iha Iron-regulated geneA homologueadhesion+ +efa-1 EHEC factor foradherence− −saa Auto agglutinatingadhesin− −lpfA Long polar fimbriae + +bfpA Major subunit ofbundle-formingpili− −katP Catalase-peroxidase − −espP Serine protease − −etpD Type II secretionsystem− −+, the gene is present; −, the gene is absent.Abbreviation: EHEC, enterohemorrhagic Escherichia coli.BRIEF REPORT • CID 2013:56 (1 January) • 115summarized in Table 1. Both strains produced Shiga toxin asdetected by the enzyme-linked immunosorbent assay. Typingthe stx2 genes revealed for both strains the variant stx2b. Inaddition, the strains of the mother and her neonate were indis-tinguishable in the PFGE analysis.DISCUSSIONWe describe clinical evidence for an STEC O146:H28 infectionleading to HUS in a neonate at the sixth day of life. STECO146:H28 was linked so far with asymptomatic carriage inhumans [8, 9].Pathogenicity of STEC is associated with various virulencefactors, the most important of which are the Shiga toxins.These toxins can be subdivided into 2 main groups, Stx1 andStx2 [10]. STEC strains pathogenic for humans tend to featureStx2 and other virulence traits as the adhesion factorintimin [11]. Of the 7 Stx2 variants described so far, the repre-sentatives of the Stx2acd group (stx2a, stx2c, stx2d), which aregenetically closely related, are reported to be strongly associat-ed with HUS in patients [11, 12]. The isolated strains,however, harbored the variant stx2b and were eae negative,which has been linked with mild clinical signs or asymptomat-ic carriage [13, 14].The mother had no gastrointestinal symptoms and thenewborn presented with vomiting without diarrhea 4 daysbefore developing hemolytic anemia and renal failure. Basedon the strain characteristics and the genotyping data, we pos-tulate that the mother is a healthy carrier, who transmittedthe STEC by the fecal-oral route to the newborn during deliv-ery. In a newborn’s sterile bowel, this STEC may be able toproliferate and lead to HUS.In newborns presenting with HUS, it is important to ruleout all causes that can lead to atypical HUS. Even though in-fectious HUS is a very rare condition in this age group, thesearch for this entity is mandatory. STEC strains belonging tothe low-pathogenic STEC group should also be considered.NotesAcknowledgments. We thank Lothar Beutin for serotyping the strainsand Grethe Sägesser, Nicole Cernela, Eveline Hofer, Christine Gallati, andMirjam Moser for their technical assistance.Financial support. This work was supported by the Gottfried andJulia Bangerter-Rhyner Foundation (to S. T.).Potential conﬂicts of interest. All authors: No reported conﬂicts.All authors have submitted the ICMJE Form for Disclosure of PotentialConﬂicts of Interest. Conﬂicts that the editors consider relevant to thecontent of the manuscript have been disclosed.References1. Besbas N, Karpman D, Landau D, et al. A classiﬁcation of hemolyticuremic syndrome and thrombotic thrombocytopenic purpura andrelated disorders. Kidney Int 2006; 70:423–31.2. Loirat C, Frémeaux-Bacchi V. Atypical hemolytic uremic syndrome.Orphanet J Rare Dis 2011; 6:60.3. Loirat C, Veyradier A, Girma JP, Ribba AS, Meyer D. Thromboticthrombocytopenic purpura associated with von Willebrand factorcleaving protease (ADAMTS13) deﬁciency in children. PediatrNephrol 2009; 24:19–29.4. Ulinski T, Lervat C, Ranchin B, Gillet Y, Floret D, Cochat P. Neonatalhemolytic uremic syndrome after mother-to-child transmission ofEscherichia coli O157. Pediatr Nephrol 2005; 20:1334–5.5. Lienemann T, Salo E, Rimhanen-Finne R, et al. Shiga toxin-producingE. coli serotype O78: H- in family, Finland, 2009. Emerg Infect Dis2012; 18:577–81.6. Murray PR, Baron EJ, Jorgensen JH, et al. Manual of clinical microbi-ology. 9th ed. Washington, DC: American Society for MicrobiologyPress, 2007.7. Kaufmann M, Zweifel C, Blanco M, et al. Escherichia coli O157 andnon-O157 Shiga toxin-producing Escherichia coli in fecal samples ofﬁnished pigs at slaughter in Switzerland. J Food Prot 2006; 69:260–6.8. Stephan R, Untermann F. Virulence factors and phenotypical traits ofverotoxin-producing E. coli strains isolated from asymptomatichuman carriers. J Clin Microbiol 1999; 37:1570–2.9. Stephan R, Ragettli S, Untermann F. Prevalence and characteristics ofverotoxin-producing Escherichia coli (VTEC) in stool samples fromasymptomatic human carriers working in the meat processing indus-try in Switzerland. J Appl Microbiol 2000; 88:335–41.10. Paton JC, Paton AW. Pathogenesis and diagnosis of Shigatoxin-producing E. coli infections. Clin Microbiol Rev 1998; 11:450–79.11. Friedrich AW, Bielaszewska M, Zhang W, et al. Escherichia coli har-boring Shiga toxin 2 gene variants: frequency and association withclinical symptoms. J Infect Dis 2002; 185:74–84.12. Persson S, Olsen KE, Ethelberg S, Scheutz F. Subtyping method forEscherichia coli shiga toxin (verocytotoxin) 2 variants and correlationsto clinical manifestations. J Clin Microbiol 2007; 45:2020–4.13. Stephan R, Hoelzle LE. Characterization of verotoxin type 2 variant B-subunit in Escherichia coli strains from asymptomatic human carriersby PCR-RFLP. Lett Appl Microbiol 2000; 31:139–42.14. Friedrich AW, Borell J, Bielaszewska M, Fruth A, Tschäpe H, KarchH. Shiga toxin 1c-producing Escherichia coli strains: phenotypic andgenetic characterization and association with human disease. J ClinMicrobiol 2003; 41:2448–53.116 • CID 2013:56 (1 January) • BRIEF REPORT

Neonatal Hemolytic Uremic Syndrome After Mother-to-Child Transmission of a Low-Pathogenic stx2b Harboring Shiga Toxin-Producing Escherichia coli

Neonatal Hemolytic Uremic Syndrome After Mother-to-Child Transmission of a Low-Pathogenic stx2b Harboring Shiga Toxin-Producing Escherichia coli

Abstract

Similar works

Full text

Available Versions

RERO DOC Digital Library