Hepatitis E virus prevalence in Egyptian children with transfusion-dependent thalassemia

w w w . e l s e v ie r . c o m / l o c a t e / b j i d

The

Brazilian

Journal

of

INFECTIOUS

DISEASES

Original

article

Hepatitis

E

virus

prevalence

in

Egyptian

children

with

transfusion-dependent

thalassemia

Doaa

Abdelmawla

_,

_Dalia

_Moemen

_,

_Ahmad

_Darwish

_,

_Wafaa

_Mowafy

a_{MansouraUniversity,FacultyofMedicine,DepartmentofMedicalMicrobiologyandImmunology,Mansoura,Egypt} b_{MansouraUniversity,FacultyofMedicine,DepartmentofPediatrics,Mansoura,Egypt}

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Articlehistory:

Received22October2018 Accepted3January2019 Availableonline28February2019

Keywords:

HepatitisEvirus(HEV) Prevalence

Thalassemia Transfusion

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HepatitisEvirus(HEV)infectionisoneofthemajorpublichealthproblemsin develop-ingcountries.HEVcancausechronicinfectionsinimmunocompromisedindividualse.g. thalassemicpatientswithincreasedriskofmorbidityandmortality.Inadditionthereis possibilityofHEVtransmissionthroughbloodtransfusion.Therefore,thepresentstudy aimedtoinvestigatetheseroprevalenceandriskfactorsofHEVinfectionin␤-thalassemic children.

Methods:Thiscross-sectionalstudywasconductedon140Egyptianchildrensufferingfrom ␤-thalassemia, attendingthe hematology outpatientclinic fromApril toOctober 2016. Serumsamplesfrompatientswerecollectedandanti-HEVantibodies;ImmunoglobulinG (IgG)andImmunoglobulinM(IgM)

weremeasuredbyenzyme-linkedimmunosorbentassay(ELISA).

Results:TheseroprevalenceofHEVin␤-thalassemicchidrenwasrelativelyhigh(27.15%). Anti-HEVIgGprevalencewas24.29%whilethatofIgMwas2.86%.Therewassignificant associationbetweenHEVinfectionandage,residence,liverenzymesandamountofblood transfusionperyear.

Conclusions:Thalasemicpatientsarevulnerabletochronicityandincreasedriskof morbid-ityandmortalityfromHEVinfection.Frequentassessmentofliverenzymesinthalassemic patientstomonitorsubclinicalHEVisrecommended.ClosemonitoringandHEVscreening ofblooddonationsshouldbetakeninconsideration.PublicawarenessaboutHEV endemi-city,modesoftransmission,andriskhazardsespeciallyinhighriskgroupshouldbedone toreducethediseaseburden.

©2019SociedadeBrasileiradeInfectologia.PublishedbyElsevierEspa ˜na,S.L.U.Thisis anopenaccessarticleundertheCCBY-NC-NDlicense(http://creativecommons.org/ licenses/by-nc-nd/4.0/).

Introduction

Hepatitis E virus infection is endemic in many develop-ingcountrieswhilesporadicHEVinfections havealsobeen

∗ _{Correspondingauthor.}

E-mailaddress:drdaliamoemen@yahoo.com(D.Moemen).

reportedinsomedevelopedcountries.1_AlthoughHEV

infec-tion isusuallyassociatedwith acute self-limitedhepatitis, fulminanthepaticfailurewithmorbidityandmortalitymay occurespeciallyinimmunocompromisedhosts.2_High

preva-lence ofHEV infection wasreported inAfrica,Central and SoutheastAsia,and Mexico.3 InFrance,the seroprevalence of HEV (anti-HEVimmunoglobulin G (IgG) and IgM) varied from 21.9% to 71.3%, according to geographic distribution,

https://doi.org/10.1016/j.bjid.2019.01.007

1413-8670/©2019SociedadeBrasileiradeInfectologia.PublishedbyElsevierEspa ˜na,S.L.U.ThisisanopenaccessarticleundertheCC BY-NC-NDlicense(http://creativecommons.org/licenses/by-nc-nd/4.0/).

withaverage39.1%.4 _{Peoplewithloweducationallevelmay}

beatahigherriskofexposureandinfectionthanthosewith highereducationallevel.InEgypt,loweducationalleveland socioeconomic status resulted in lack of knowledge about avoidablepossibleriskfactorsassociatedwithHEVinfection. ThusHEVwashighlyendemicinEgyptianruralcommunities withgenotype1subtype3mostcirculating.5,6_Therearefour

documentedroutesoftransmissionofHEVincluding fecal-oralroute,vehicle-borneincludingwater-borneandzoonotic foodborne,bloodbornetransmissionthroughparenteralblood transfusion, and perinatal via vertical transmission from mother-to-infant.7,8 _{ChronicHEVinfection was acquired in}

1.4%ofpatientsfollowinglivertransplantion which subse-quently resulted in persistent damage of the liver graft.9

Thalassemiais one ofthe most common genetic diseases worldwide.Itisamajorpublichealthproblem,causingmuch morbidity,earlymortality,andgreatfinancialandemotional burdenforafamily.Thalassemiaisthemostcommonform ofinheritedanemia aroundtheworld.10 _{␤-thalassemia}

fre-quenciesarecommoninalmostallArabcountries.11_InEgypt,

␤-thalassemiaisthe mostcommontypewithacarrierrate ranging from 5.3% to ≥9%. It was estimatedthat 1000/1.5 million live births/year suffer from thalassemia disease in Egypt.12_{Manythalassemiapatientsdevelopchronicliver}

dis-ease(CLD)likechronichepatitisC.HAVandHEVinfections showmoresevereclinicalcoursesintheCLDpatients.13_Some

authorsdocumentedHEVseropositivityamonghemodialysis andthalassemiapatients.14,15 _{ItwasreportedthatHEVRNA}

detectedinblooddonationsthroughstudiesbybloodbanks inseveral Europeancountries.16 _{Therefore, somecountries}

began HEV RNA screening of blood donations and others selectivelyappliedbloodscreeningforhighriskpatients.17_A

previousstudyconductedonpatientswithacuteviral hep-atitisinEgyptreportedHEVinfectioninabout12–42%ofall cases.18_{Anotherstudycarriedoutonbloodsamplescollected}

from134jaundicedpatientsinEgypt,revealedthat51(38.1%) patientswerepositiveforanti-HEVIgG.19Also,studyon chil-drenwithacuteviralhepatitisinAssiut,Egypt,detected30.9% HEVinfectioninchildren.20_{Thepresentstudyaimedtodetect}

theseroprevalenceofHEVinfectioninthalassemicchildren toassesstheroleofbloodtransfusionasariskfactorforHEV infection.

Patients

and

methods

Thiscross-sectional study was conductedon 140 Egyptian childrensufferingfrom␤-thalassemia,attendingthe hema-tology outpatient clinic in Mansoura University Children’s Hospital (MUCH) from April 2016 through October 2016. Patients included in this study were patients with beta-thalassemia aged up to 18 years who frequently received bloodtransfusion.However,patientswithhemolyticanemia otherthanthalassemia,patientswithalpha-thalassemia,and patientswithlessthan10bloodtransfusionswereexcluded from the study. This study was approved by the Medical Research Ethics Committee, Mansoura University (IRB no. MS/16/03/82).

Datacollectedfrompatients

Data collected from patients included age, sex, residence, amountofbloodtransfusedperyear,abdominalexamination ofliverandspleen,serumferritin,liverfunctiontests(ALTand AST),andviralhepatitismarkers(HBsAgandHCVAbs).

Samplecollectionandprocessing

Two milliliters of venous blood were obtained from each selected patient and collected in a sterile tube, cen-trifugedimmediately forserum separation. Serumsamples were stored at −20◦_{C. Presence of anti-HEV antibodies}

(anti-HEV IgG indicating past infection and anti-HEV IgM indicating recent infection) in the patients’ sera were measured by enzyme-linked immunosorbent assay; HEV-IGMElisa (Immunospec, USA,BL147710) andHEV-IGG Elisa (Immunospec,USA,BL147709).

Statisticalanalysis

Thecollecteddatawascoded,processedandanalyzedusing SPSS (Statistical package for social science) version 23 for windows.Descriptivestatisticswerecalculatedbyfrequency (number-percent). Chisquaretestwasused forinter-group comparisonofcategoricaldata.p-Value lessthan 0.05 (5%) wasconsideredstatisticallysignificant.Significantvariables onunivariateanalysiswereenteredintoalogisticregression model to determine which of thesefactors were indepen-dentlyassociatedwithHEVinfection,followedbymultivariate analysis.

Results

The seroprevalence of HEV antibodies in ␤-thalassemic patients was 27.15%(38/140 patients); 34 (24.29%) patients were positive for anti-HEV IgG, and four (2.86%) patients were positiveforanti-HEVIgM.Asshown inTable1,there was significant association between age and anti-HEV IgG andIgMseropositivity(p=0.004,and0.044,respectively).HEV seropositivityincreasedwithage.Therewassignificant asso-ciationbetweenruralresidenceandanti-HEVIgG(p<0.001). Regarding clinical data, there was significant association between liver enzymes and anti-HEV IgG. No patients in our study had HBV infection.Splenectomy andHCV infec-tionwerenotsignificantlyassociatedwithHEVseropositivity (Table 2). Table 3. In Univariate analysis, there was sig-nificantassociation betweenAge,residence, liverenzymes, and amount of blood transfusions per with HEV seropos-itivity. On multivariate analysis only rural residence and elevatedALTlevelswereindependentlyassociatedwithHEV seropositivity.

Discussion

TheprevalenceofHEVantibodies amongthalassemic chil-dreninourstudy was27.15%,24.29%anti-HEVIgGpositive and 2.86% anti-HEVIgM positive.Resultsofprevious stud-ies showed seroprevalence of HEV antibodies of 2.4% in

Table1–DemographicdataassociatedwithHEVseropositivityinthalassemicchildren.

Demographicdata Anti-HEVIgG Anti-HEVIgM

Positive(n=34) Negative(n=106) p-Value Positive(n=4) Negative(n=136) p-Value

Agerange(years) 2–6 5(14.7%) 33(31.1%) 0.004a _{0(0.0%) 38(27.9%) 0.044}a

6–12 14(41.2%) 55(51.9%) 1(25.0%) 68(50.0%) 12–18 15(44.1%) 18(17.0%) 3(75.0%) 30(22.1%) Sex Female 16(47.1%) 49(46.2%) 0.933 1(25.0%) 64(47.1%) 0.383 Male 18(52.9%) 57(53.8%) 3(75.0%) 72(52.9%) Residence Rural 28(82.4%) 51(48.1%) <0.001b _{3(75.0%) 76(55.9%) 0.447} Urban 6(17.6%) 55(51.9%) 1(25.0%) 60(44.1%) n,number. a _{Significance<0.05.} b _{Highsignificance.}

Table2–ClinicalparametersassociatedwithHEVseropositivityinthalessemicchildren.

Clinicaldata Anti-HEVIgG Anti-HEVIgM

Positive(n=34) Negative(n=106) p-Value Positive(n=4) Negative(n=136) p-Value

Splen-ectomy Yes 16(47.1%) 42(39.6%) 0.444 2(50.0%) 56(41.2%) 0.724 No 18(52.9%) 64(60.4%) 2(50.0%) 80(58.8%) HCV Positive 11(32.4%) 25(23.6%) 0.309 1(25.0%) 35(25.7%) 0.974 Negative 23(67.6%) 81(76.4%) 3(75.0%) 101(74.3%) HBV Positive 0(0.0%) 0(0.0%) – 0(0.0%) 0(0.0%) – Negative 34(100.0%) 106(100.0%) 4(100.0%) 136(100.0%) ALT Elevated 28(82.4%) 47(44.3%) <0.001b _{4(100.0%) 71(52.2%)} 0.059 Normal 6(17.6%) 59(55.7%) 0(0.0%) 65(47.8%) AST Elevated 23(67.6%) 39(36.8%) 0.002a _{3(75.0%) 59(43.4%) 0.210} Normal 11(32.4%) 67(63.2%) 1(25.0%) 77(56.6%) ALT,alaninetransaminase;AST,aspartatetransaminase;n,number.

a _{Significance<0.05.} b _{Highsignificance.}

Table3–UnivariateandmultivariateanalysesoffactorsassociatedwithHEVseropositivityinthalassemicchildren.

Univariateanalysis Multivariateanalysis

pValue OR 95%C.I. pValue OR 95%C.I.

Age(years) 0.001a _{1.18 1.07–1.29} Malesex 0.807 1.098 0.52–2.32 RuralResidence 0.001a _{4.98 2.01–12.35 0.003}a _{4.277 1.65–11.09} Splenectomy 0.385 1.39 0.66–2.96 AbnormalAST 0.001a _{3.97 1.79–8.80} AbnormalALT <0.001a _{7.32 2.81–19.04 <0.001}b _{6.486 2.43–17.32}

Amountofbloodtransfused(mL/year) 0.008a _{1.00 1.00–1.00}

Serumferritin(␮g/L) 0.313 1.00 1.00–1.00

ALT,Alaninetransaminase;AST,Aspartatetransaminase;p,probability;OR,odd’sratio;CI,confidenceinterval.

a _{Significance<0.05.} b _{Highsignificance.}

thalassemic patients in Scandinavia21 _{and 10.7% in Saudi}

Arabia.22 _{In Iran, the seroprevalence of HEV IgG and HEV}

IgMwere10%and1.8%,respectively.15 _{Reasonssuchas}

dif-ferences in socioeconomic, cultural, hygienic, and climatic factorsacrossgeographicalareasmayexplainthelower preva-lencerates indevelopedcountriescomparedto developing countries.24_{Inourstudy,agewassignificantlyassociatedwith}

HEVantibodies. ThehighestHEVprevalence ratefound in the age group 12–18 years indicated that the risk of HEV infectionincreasedwithage.Previousstudiescarriedoutin

Egypt25 _{andinother geographic regionsreportedthe same}

finding.26–28 _{Thiscould beexplained bythefact that older}

childrenhadlikelyreceivedmoretransfusedblood,in addi-tiontohavebeenmoreexposed tocontaminatedjunkfood than youngerchildren.Inthisstudy,the prevalenceofHEV antibodies in ruralareas (81.6%) washigher than inurban areas(18.4%).InruralEgypt,morethan60%ofchildrenwith agedover10yearshadpositiveanti-HEVIgG.29 _Onthe

con-trary,anotherstudyconductedonHCVinfectedthalassemic patients in Iranreported higher HEV seropositivity in

tha-lassemicpatientsfromurbanregionsthanthosefromrural areas.6_{Regardingliverenzymes,84.2%ofpatientswithHEV}

seropositivityshowedelevatedALTlevels,comparedto68.4% ofelevated AST levels. Liver enzymes were higher among thosewithnon-HEVantibodiescomparedtothosewithHEV antibodies.Thismaybeduetopresenceofother causesof hepatitiseitherviralcauses,mostlyHCV,ornon-viralcauses. Although100%and75%ofanti-HEVIgMpositivepatientshad elevatedALT andASTlevels,respectively,therewasno sig-nificantassociationbetweenliverenzymesandanti-HEVIgM seropositivity,probablyduetosmallnumberofanti-HEVIgM positivepatients. Previousstudiesreported thatsubclinical HEVinfectionmightbethecause ofelevatedALT.30

There-fore, in casesof unexplained ALT and AST elevation, HEV may bethe reasonablecause.In two studiesconducted in Japanon voluntary blood donorswith elevated ALT levels, anti-HEVIgGwaspositivein3.7%and7.1%ofparticipants.31,32

Thesefindingssuggestthat patientswithongoing subclini-calHEVinfectionhadthepotentialtotransmitHEVthrough bloodtransfusion.Ourstudyrevealedthattherewas signifi-cantassociationbetweentheamountofbloodtransfusedper year and HEV seropositivity (p=0.008).On the other hand, apreviousstudyshowednosignificantassociationbetween theamountofbloodtransfusedandanti-HEVseropositivity inthalassemicpatients.21_{Thisdifferencemaybedueto}

geo-graphicdifferenceanduseofassayswithlowsensitivitythat couldunderestimateHEVprevalence.33_{Studiesconductedin}

bloodbanksofseveralEuropeancountriesreportedthatabout 0.02–0.14%ofblooddonationswereHEVRNApositive.16,34_This

findingsupportsthepossibilityofHEVtransmissionthrough bloodtransfusion.SincerecentlyinIreland,blooddonations are routinely screenedforHEV RNA.Also in2017, the UK, andNetherlandsbegan HEVRNAscreeninginblood dona-tions.In France and Germany,screening selectively occurs inhigh-riskpatients,whilebloodauthoritiesinItaly,Spain, Portugal and Greece are assessing whether HEV screening shouldbeimplementedornot.17_{Apreviousstudyconducted}

inEgyptshowedthatabout0.45%ofblooddonorshave ongo-ingsubclinicalHEVinfection.35_{Itwasreportedthattheriskof}

transmissionthroughbloodtransfusionisincreasedin high-riskpatientsindevelopingregionsthaninotherlocations.23

HEVisendemicinEgyptandbesidesthepossibilityofHEV transmission through blood, our study showed significant association between amount of blood transfused and HEV seropositivity. Therefore, further studies should be carried outtodetectHEVinfectioninriskgrouppatientsandblood donors.

Conclusion

In conclusion, the seroprevalence ofHEV in ␤-thalassemic patientswasrelatively high.Therefore, closemonitoringof thesepatientsinadditiontoHEVscreeningofblooddonations shouldbetakenintoconsideration.Frequentassessmentof liverenzymesin␤-thalassemicpatientstomonitor subclini-calHEVinfectionsandotherviralinfectionsisrecommended. PublicawarenessaboutHEVendemicity,modesof transmis-sion,andriskhazards,especiallyinhigh-riskgroupsshould bedonetoreducethediseaseburden.

Funding

Theauthorsreceivednospecificfundingforthiswork.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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