J. Pediatr. (Rio J.) vol.92 número5

www.jped.com.br

ORIGINAL

ARTICLE

Fecal

calprotectin

levels

in

preterm

infants

with

and

without

feeding

intolerance

夽

Rehab

Moussa

_,

_Abdelmoneim

_Khashana

,

Noha

Kamel

,

Sonia

Elsharqawy

Elsharqawy

a_{SuezCanalUniversity,FacultyofMedicine,DepartmentofPediatrics,Ismailia,Egypt}

b_{UniversityofOulu,MedicalResearchCenter(MRC),ResearchUnitofPediatrics,PediatricNeurology,PediatricSurgery,}

ChildPsychiatry,Dermatology,ClinicalGenetics,ObstetricsandGynecology,Otorhinolaryngology,Ophtalmology(PEDEGO), Oulu,Finland

c_{SuezCanalUniversity,FacultyofMedicine,DepartmentofClinicalPathology,Ismailia,Egypt}

Received12September2015;accepted25November2015 Availableonline16June2016

KEYWORDS

Fecalcalprotectin; Feedingintolerance; Preterminfants

Abstract

Objectives: Toassesstheleveloffecalcalprotectininpretermneonateswithfeeding

intoler-ance,aswellastoevaluateitasamarkeroffeedingintoleranceandtodetermineacut-off leveloffecalcalprotectininfeedingintolerance.

Methods: Analytical,multicenter,case---controlstudy,whichwascarriedoutinneonatal

inten-sive careunits inEgypt, ina period fromAugust 1, 2014 toMarch 1, 2015on 52 preterm neonates.Neonateswereclassifiedintotwogroups;astudygroupincluding26neonateswho metinclusioncriteriaandacontrolgroupincluding26neonatesforcomparison.

Results: Fecalcalprotectinlevelsrangedfrom3.9␮g/gto971.8␮g/g,andtherewasa

signif-icantincreaseinfecalcalprotectin inthestudygroupwhen comparedtothecontrolgroup (334.3±236.6␮g/gvs.42.0±38.2␮g/g,respectively)withmoderateinversesignificant cor-relation between fecal calprotectin and birth weight. Furthermore, there was moderate, significantcorrelationbetweenfecalcalprotectinanddurationofbreastfeedingrange.Onthe otherhand,therewasnocorrelationbetweenfecalcalprotectinandpost-natalage,gestational age,orvolumeoffeeding.Acut-offatthe67.0␮g/glevel,with100.0%sensitivityand76.9% specificity,wasconsidered.

Conclusion: Fecalcalprotectinlevelincreasedsignificantlyinneonateswithfeeding

intoler-ance;itcanbeusedtodetectearlycaseswithnecrotizingenterocolitisinneonates,butthis subjectstillneedsmoreinvestigationsonmorepatients.

©2016SociedadeBrasileiradePediatria.PublishedbyElsevierEditoraLtda.Thisisanopen accessarticleundertheCCBY-NC-NDlicense(http://creativecommons.org/licenses/by-nc-nd/ 4.0/).

夽

Pleasecitethisarticleas:MoussaR,KhashanaA,KamelN,ElsharqawySE.Fecalcalprotectinlevelsinpreterminfantswithandwithout feedingintolerance.JPediatr(RioJ).2016;92:486---92.

∗_{Correspondingauthor.}

E-mail:[email protected](A.Khashana).

http://dx.doi.org/10.1016/j.jped.2015.11.007

PALAVRAS-CHAVE

Calprotectinafecal; Intolerância alimentar;

Neonatosprematuros

Níveisdecalprotectinafecalemneonatosprematuroscomesemintolerância

alimentar

Resumo

Objetivos: Avaliaronível de calprotectinafecal em neonatos prematuros comintolerância

alimentar, alémdeavaliá-locomo umindicador deintolerância alimentaredeterminarum níveldecortedacalprotectinafecalnaintolerânciaalimentar.

Métodos: Estudocaso-controleanalítico,realizadoemummulticentrodeunidadesdeterapia

intensivaneonataisnoEgito,noperíodode1◦_{deagostode2014a1}◦ _{demarc¸ode2015,com} 52neonatosprematuros.Osneonatosforamclassificadosemdoisgrupos;umgrupodeestudo incluindo26neonatosqueatenderamaoscritériosdeinclusãoeumgrupodecontroleincluindo 26neonatosparacomparac¸ão.

Resultados: Osníveis decalprotectina fecalvariaram de3,9␮g/ga971,8␮g/g ehouveum

aumentosignificativodacalprotectinafecalnogrupodeestudoquandocomparadoaogrupo de controle (334,3±236,6␮g/g em comparac¸ão a 42,0±38,2␮g/g, respectivamente) com correlac¸ãoinversa,moderadasignificativaentreacalprotectinafecaleopesoaonascer. Adi-cionalmente,houvecorrelac¸ãomoderadasignificativaentreacalprotectinafecaleadurac¸ão dointervalodeamamentac¸ão.Poroutrolado,nãohouvecorrelac¸ãoentreacalprotectinafecal eaidadepós-natal, aidade gestacionalouovolumedeamamentac¸ão.Foi consideradoum cortenosníveisde67,0␮g/g;comsensibilidadede100,0%eespecificidadede76,9%.

Conclusão: O nível de calprotectina fecal aumentou significativamente em neonatos com

intolerância alimentar e podemos utilizá-lo para detectar casos precoces comenterocolite necrosanteemneonatos,porémaindasãonecessáriasmaisinvestigac¸õesemmaispacientes.’ ©2016SociedadeBrasileiradePediatria.PublicadoporElsevierEditoraLtda.Este ´eumartigo OpenAccesssobumalicenc¸aCCBY-NC-ND(http://creativecommons.org/licenses/by-nc-nd/4. 0/).

Introduction

Feedingofpretermneonatesisoneofthemainchallenges facedbyneonatalpractitioners,especiallythoseinthelow birthweightgroups.1 _{Pretermneonateshave greater} mor-talityandmorbiditywithlong-termdisorders.2

Feeding intolerance is knownas a difficulty in feeding milk, causing a change in the usual enteral feeding due to the appearance of one or more of the following gas-trointestinalclinicalsymptoms:gastricresiduals,vomiting, abdominaldistention, distended bowelloops, and change incharacterofstool.Apnea,bradycardia,andtemperature instabilityarealsoincludedassymptomsoffeeding intoler-ance,butonlyforthereasonofnursingjudgment,inorder togiveguidanceondetectionofprogressiontomoreserious complicationssuchasnecrotizingenterocolitis(NEC).3

Many risk factors may aggravate feeding intolerance, includingpoorcoordinationofsuckingandswallowing,weak loweresophagealsphincter,smallstomachcapacity,delayed stomachemptyingtime,andintestinalhypomotility4_;onthe otherhand,humanmilkisthebestforneonatesand forti-fiersderivedfromhumanmilkactasagoodsubstratumfor preterminfantfeeding.5

Abnormalbacterialcolonizationmaybeafactorin feed-ing intolerancein neonates, mainlydue todysfunctionof theintestinalbarrier,theimmuneresponses,andfunctions oftheintestine.Abnormalintestinalcolonization,poor bal-ancebetweenmicrobiota,immuneresponse,andtolerance mechanismsmayresultinfeedingintoleranceinpostnatal lifeandalsoingastrointestinaldiseaseinchildhood.6

In1970,Fagerholetal.searchedforamarkerof leuko-cyteturnover, and in 1980 theypublished their discovery of a protein in the cytoplasm of neutrophils, which they termedleukocyte-derivedL1protein,orcalprotectin.7 Cal-protectinis a member of the S100family of calciumand zincbindingproteins;itistheheterodimerofS100A8/A9. Itisfound inneutrophils,monocytes,andsome squamous epithelium cells. The complex accounts for up to 60% of thesolubleproteincontentoftheneutrophilcytoplasm.It isreleasedbyactivationof leucocytesasconsequencesof inflammatorydiseases.8_{S100A8isalsocalledcalgranulinA} andmyeloid-relatedprotein8(MRP8),andS100A9iscalled calgranulinB(MRP14).Theyboth arelinkedtotheinnate immunesystem.9

Calprotectinhas bacteriostaticand fungistaticactions, asitcanisolatemanganeseandzincintheircells10_;italso hasseveralbiologicalpropertiesincludingantimicrobicand imunomodulatoryactivity,anditisreleasedduringcell acti-vation(activerelease)orcelldeath(passiverelease).11 _It hasbeen suggestedasausefulindicatortodeterminethe severityofinflammationintheintestine.12_Themost signifi-cantfactorsthataffect fecalcalprotectin (FCP)excretion include ante- and perinatal antibiotic treatment, volume ofenteralfeeding,theoccurrence ofunplanned interrup-tionsofenteralfeeding,andthegastrointestinalbacterial colonization.13

The present study aimed toassess the level of FCPin preterm neonates withfeeding intolerance, aswell as to confirmitasamarkeroffeedingintoleranceandto deter-mineacut-offlevelofFCPthatisspecificandsensitiveto feedingintolerance.

Methods

Studydesign

Analyticalcase---controlstudy

Thestudypopulationwasclassifiedintotwogroups:Group1 (casegroup)includedpreterminfantsthatfulfilledinclusion criteriaandshowedanysignoffeedingintolerance.Group 2(control group)included postnatal age-,gestation-,and sex-matchedcontrolpretermbabieswhodidnotshowsigns offeedingintolerance.

Inclusioncriteria:Preterminfantsofbothgendersfrom birthuntilthe28thdayoflifeandwith28tolessthan37 weeksofgestation,admittedtotheneonatalintensivecare unit(NICU),whoshowedanyofthesignsoffeeding intoler-anceleadingtointerruptionofthecurrentfeedingregime, suchas:increasedgastric residuals(>50%)of theprevious feeding,emesis,abdominaldistention(increasein abdomi-nalgirthby2cmormorebetweenfeedings),bloodystool, diarrhea,andvisiblebowelloops.3

Exclusion criteria: Neonates suffering from intestinal congenitalanomaliesorneonateswithsepsis.3

Sample size:Thefollowing equationusedtodetermine therequiredsamplesize:

N=2(Z␣+Z␤)2×P−Q−/(P1−P2)2

where:N=number; Z␣=thevalueof standardnormal dis-tributionfortypeIerrorprobabilityforonesidedtestand equal1.96for95%significance;Z␤=thevalue ofstandard normaldistributionforthedesiredstatisticalpowerof90% andequal1.28for90%power;P−_=(P1_+P2_)/2;Q−_=1−P−_; P1_{=56%, is the estimated proportionof an attribute that} is present in the population1_{; P}2_{=prevalence of neonates} expectedtohavelowFCPlevelequals5%.

Accordingtothecalculation thesample sizetotaled52 neonates:26neonatesfromeachgroupwhowereadmitted totheNICUintheperiodbetweenthe1stofAugust,2014 untilthe1stofMarch,2015.

Allthestudiedneonatesweresubjectedtohistory tak-ing,fullclinicalexamination,andinvestigations:C-reactive protein,completehemogram,andFCP.

FCPwasmeasuredinstoolusingtheRidascreen quantita-tiveenzymelinkedimmunoassay(BiopharmAG,Darmstadt, Germany)

Statisticalanalysis

Thecollected datawereorganized,tabulated, and statis-ticallyanalyzedusingSPSSversion16(SPSS,Inc.,Chicago, USA),running onan IBM(InternationalBusiness Machines, New York, USA) compatible computer. Qualitative data (categorical) were represented as relative frequency and percentdistribution,andfor comparisonbetween groups,

chi-squared(X)wasusedasatestofcomparison. Quantita-tivedatawererepresentedasmeanandstandarddeviation (SD).Forcomparisonbetweengroups, Student’st-testfor independent samples was used for normally distributed data;theMann---Whitney(U)testwasusedfornon-normally distributeddata.Forcorrelation,thePearson’scorrelation coefficient(r)wasused;correlationwasproportionalifthe sign was positive; inverse if the sign was negative; mild if <0.3; moderate if 0.3---0.7; and powerful if >0.7; com-plete correlation if r=1.0;and nocorrelation whatsoever ifr=0.0.Forinterpretationofresults,p-values<0.05were consideredsignificant.

Ethicalconsideration

Ethicalapprovalofthestudywasobtainedfromtheresearch ethics committee of the faculty of medicine of the Suez CanalUniversityinandawritteninformedparentalconsent alsowasobtained.

Results

Regardingdemographiccharacteristics(Table1)

It was found that there was no significant difference betweenthestudygroupandcontrolsregardingsex distri-bution.Theneonatesincludedrangedfrom28to36weeks gestationandtherewasnosignificantdifferencebetween bothgroups withregardstogestationalage(32.2±2.7vs.

32.3±2.4weeks,respectively). Theirbirth weightranged from 900g to 2750g and there was no significant differ-enceof birth weightbetween both groups. Regarding the modeofdelivery; 11cases(21.2%)weredeliveredby nor-malvaginaldeliveryand41cases(78.8%)weredeliveredby cesarean delivery; therewasno significant differencefor normalvaginaldeliveryinthisstudywhencomparedtothe controlgroup.Post-natalagerangedfrom3rdto25thdays, withanon-significantincreaseofpost-nataldaysinthestudy groupwhencomparedtothecontrolgroup.

The main illness in the study and control groups was respiratorydistressin37cases(71.2%);respiratorydistress syndrome(RDS)intencases(19.2%);transienttachypneaof newborn inthreecases (5.8%);RDSplus hypoxic ischemic encephalopathy in one case (1.9%); and persistent pul-monaryhypertensionofnewborn(PPHN)inonecase(1.9%); therewerenosignificantdifferencesbetweengroups.

As to type of feeding; it wasexclusive artificial feed-ing in 41 cases (78.8%); exclusive breast feeding in one case (1.9%) and mixed (artificial with breast feeding) in ten cases (19.2%),with nosignificant difference between groups.Feedinginthestudygroup(volume/3h)rangedfrom 1mLto30mLwithameanof18.4±7.8mL;andtherewas anon-significantdecreaseoffeedingvolumeinbothgroups (Table2).

Table1 Demographiccharacteristicsinstudyandcontrolgroups.

Variable Group p-value

Study(26) Control(26)

n % n %

Sex

Male 11 42.3 14 53.8 0.41(NS)

Female 15 57.7 12 46.2

Gestationalage(weeks),mean±SD 32.2±2.7 32.3±2.4 0.91(NS)

Birthweight(g),mean±SD 1865.0±548.0 1932.3±459.5 0.63(NS)

Postnatalage(days),mean±SD 10.0±5.7 8.3±4.5 0.23(NS)

Deliverymode

Normal 6 23.1 5 19.2 0.73(NS)

CS 20 76.9 21 80.8

CS,cesareansection;NS,non-specific.

Table2 Typeoffeedinginstudyandcontrolgroups.

Variable Group p-value

Study Control

n % n %

Feeding

Artificial 20 76.9 21 80.8 0.49(NS)

Breastfeeding 1 3.8 0 0.0

Artificial+BF 5 19.2 5 19.2

Volumeoffeeding,mean±SD 17.0±8.5 19.7±7.0 0.23(NS)

BF,breastfeeding;NS,non-specific.

inonecase(3.8%).Altogetherfivecases(9.6%)withStage IAreportedtohaveNECinthestudygroup.

FCPlevelsrangedfrom3.9␮g/gto971.8␮g/g,witha

sig-nificantincreaseofFCPinthestudygroupwhencomparedto thecontrolgroup(334.3±236.6␮g/gvs.42.0±38.2␮g/g,

respectively),andwithmoderateinversesignificant corre-lationbetween FCPand birth weight.Furthermore,there wasmoderate,significantcorrelationbetweenFCPandstop feedingduration.Conversely,therewasno-significant cor-relationbetweenFCPandpost-natalage,GA,orvolumeof feeding(Table3).

Analysis of ROCcurve showedthat the areaunder the curvewas0.97(thisreflectedhighersensitivity);forthebest cut-off,valueswiththebestsensitivitywerechosen;atthe levelof67.0␮g/g,thesensitivitywas100.0%andspecificity was76.9%(Table4).

Discussion

Feedingintoleranceisverycommonamongpreterminfants onenteralfeeds,andmayeitherbeabenignsignofreduced GImotilityor maybean initialmanifestationof necrotiz-ingenterocolitis(NEC).It isone ofmost commonreasons todelayadvancementofenteralfeedsorforsuspensionof feedsinpreterminfants.19_{FCPhasbeensuggestedtobea} usefulmarkerofgastrointestinalinflammationinneonates, and has also been raised in cases of inflammatory bowel disease.20

The present patients’ gestational age ranged from 28 to36 weeks, with mean of 32.3±2.6 weeks, mean birth weightof1898.7±501.9g,andmeanpostnatalageattime ofdiagnosisof10.0±5.7days.Itwasfoundthat11ofthe studygroupweremalesand15werefemales.Inthestudy

Table3 Fecalcalprotectininstudyandcontrolgroups.

Group Median Mean SD Minimum Maximum U p-value

Study 273.85 334.33 236.61 67.30 971.80 20.0 <0.001a

Control 23.95 42.03 38.23 3.90 126.10

a _{RegardingFCPlevels,becausethedatawerenon-normallydistributed,themedianwastheappropriatemeasureandMann---Whitney}

Table4 SensitivityofFCPindiagnosisoffeedingintolerance.

Positiveifgreaterthanorequalto Sensitivity Specificity 1−Specificity

59.70 1.000 0.731 0.269

67.05 1.000 0.769 0.231

72.15 0.962 0.769 0.231

79.65 0.962 0.808 0.192

Areaunderthecurve 0.97

95%CI 0.00---1.00

FCP,fecalcalprotectin.

byZoppellietal.,21 _{theyfoundthatthe meangestational} age (GA)was28.5 weeks and birth weightwas1057g.In the study by Albanna et al.,16 _{they found a mean GA of} 32weeks,ameanbirthweightof1500g,andameanage atdiagnosis of 9 days;ninewereboys andsix weregirls. Cui andLi14 _{hada mean GA of 30 weeks,withmean age} atdiagnosis of12 days.Inthestudy byCarroll,22 _samples wereobtained(oneat birthandtheother onthe3rdday afterbirth)from38preterminfants withGAranging from 29to33 weeks.Aydemiretal.17 _{foundmeanbirth weight} of950g,andameanageof14daysatdiagnosis.

Altogether,41neonateswereexclusivelyfedartificially, tenhadmixedfeeding,andonlyonecase wasexclusively breastfed,unlikethestudybyYoon,15 _{inwhichnoinfants} wereexclusivelybreastfed.

The present study found no significant correlation between FCPlevel and volumeof enteral feeding, which agreeswithCampeottoetal.23_{anddiffersfromthestudyby} Yangetal.,24_{inwhichFCPlevelsdecreasedwithincreasing} enteralfeedingvolumeduringthefirstmonthofpostnatal life,andfromJosefesson etal.25 _{andRougéetal.,}13 _who foundthatFCPincreasedwithincreasingfeedingvolume.

Previousstudieshaveresearchedtheeffectofthetype offeedingonthelevelofFCP:Campeottoetal.23_andYang etal.24 _{foundthatthereisnodifferenceintheFCPlevels} ofinfantsfedmaternalbreastmilkvs.hydrolyzedformula. Yoon et al.15 _{found that there was no effect of type or} methodoffeedingonFCP,whileLietal.26 _foundthatFCP levelwashigherin breastfedinfants than informulafed infants.Inthepresentstudyitwasnotpossibletoexamine therelationshipbetweenexclusivelybreastfedand exclu-sivelyformulafedinfants,astherewasonlyoneexclusively breastfedinfant.

Thisstudyfoundnoeffectofgenderorgestationalageon levelofFCP,whichisinagreementwithCampeotoetal.,23 andalsomatcheswithYangetal.24 _{andKapeletal.,}18 _but isin disagreementwithRougé etal.,13 _{whofound aweak} negativelinear relationship between FCPand gestational age.Yoonetal.15 _{foundaclearpositivelinearrelationship} betweentwothevariables(gestationalageandlevelofFCP) innewbornsbornat<26weeksGAandadistinctivenegative linearrelationshipbetweentheminnewbornsbornafteror atweek26to<30weeks.

TherewasasignificantinversecorrelationbetweenFCP levelandbirthweight,inagreementwithLaforgiaetal.27 andindisagreementwithCampeottoetal.,23_whofoundno significantrelationbetweenbirthweightandFCP.

In the present study there was a significant posi-tivecorrelationbetweenprematureruptureofmembranes

(PROM) andlevel of FCP. This was in agreementwith Cui andLi.14

Itwasfoundthatpostnatalagehasnosignificant correla-tionwithFCPlevel;thiswasinagreementwithCampeotto et al.23 _{and in disagreement withJosefesson et al.}25 _and Rougé et al.,13 _{whoobserved a positive relationship, and} Yang et al.,24 _{who found a negative relationship, as FCP} levelstendedtodecreasewithincreasingage.

Therewasnocorrelationbetweenmodeofdeliveryand FCPlevel.ThiswasinagreementwithLaforgiaetal.27 _and Rougéetal.,13_{andindisagreementwithJosefessonetal.,}25 who observedpositive relationship withcaesarian section (CS)delivery,andCuiandLi,14_{whoobservednegative} rela-tionshipwithCSdelivery.

Inthepresentstudygroup,fourpreterminfantsdied dur-ing the time of study.Twenty-six preterm were found to have signsoffeedingintolerance;fiveofthem (9.6%)had suspectedNEC(bell’sstageIA);allofthemhaverecovered completelyexceptforonecase whodiedduringthestudy. In the study by Zoppelli et al.,21 _{9.2% of patients} devel-opedNECstageII,ofwhomfivehadfulminantNEC.Aydemir etal.17_{observedthreepatientswithmildNEC(Bell’sstage} IB),fourwithdefiniteNEC(Bell’sstageIIB),andthreewith clinicalsignsconsistentwithadvancedNEC(Bell’sstageIIIA orIIIB).

The FCPlevel inthe present study rangedfrom 3.9to 971.8mg/kg,withameanof188.2±223.5.FCPwas signif-icantlydifferentbetweengroups,withhigherFCPlevelsin thecase group,whichwasin agreementwithCuietal.,14 whostatedthattherewasincreasedFCPlevelinthegroup withfeedingintolerance;this wasalsoinagreementwith Rougé etal.,13 _{whostated thatFCP increasedin preterm} with poor tolerance to enteralfeeding. Also, this finding matched withYangetal.,24 _{whofound thatthe FCPlevel} in preterminfants rose aroundthetimeof initialsigns of GI illness and decreased asthese signs were treated and resolved,andthatFCPwasgreater amongthosewithNEC symptoms.

valueof 363␮g/gwithasensitivity0.65andspecificityof 0.82wasset forthe developmentof mild digestive symp-toms,andacut-offof636␮g/gwithasensitivity0.72and specificity 0.95for the developmentof severe symptoms. Shenoyetal.28 _{showedthattherewasasignificant} associ-ationbetweenhigh FCPandNEC.FCPhada cut-offvalue ≥280␮g/g,andasensitivityof93.3%andspecificityof39%. The present studydemonstrated that therewasa cor-relationbetweenhigherFCPlevelsandNECoccurrencein thecasegroup;thisisinagreementwithAlbannaetal.,16 whofound significantlyhigherFCPlevelsinneonates who developedNEC,withmaximumlevelinneonateswithBell’s stageIIIb(307.6±4.1),which wasalsoinagreementwith Aydemir et al.,17 _{who found that raised FCP can predict} theoccurrenceofNEC,asmeanFCPconcentrationsinNEC cases (185mg/dL) were significantly higher than controls (104mg/dL). Also,theyfound thattherewasasignificant positive correlation between NEC severity and FCPlevel. Yoonetal.15 _{alsofoundthatFCPconcentrationwashigher} innewbornswithNECthancontrols.ElFragyetal.29_showed that FCP can be usedas a non-invasive marker for early predictionofNECinneonates.

InastudybyThuijlsetal.thatinvolved35neonates sus-pectedofNEC,14ofthemdevelopedNEC.MedianofFCP levelstogetherwithurinaryintestinalfattyacidbinding pro-teinandclaudin-3weresignificantlyhigherinneonateswith NECthaninneonates withother diagnoses,withacut-off levelofFCP(286.2␮g/gfeces).30Carrolletal.showedthat FCPwasmarkedlyelevated---withameanconcentrationof 288.4mg/L---inpatientswithNEC,comparedto98.0mg/Lin controls.22_{FCPwasincreasedto>2000}

␮g/ginthreecasesof NECandinonecaseofcoveredperforationwithmicroscopic bowelinflammation.25

Allofthe52studiedneonateswereundertreatmentwith antibiotics, sowe were notable toidentify theeffectof postnatalantibioticsonFCPlevel.Fecalsampleswerenot alwayseasilyobtainableininfantswhohadfeeding intoler-ance,astheyhaddelayedgastricemptying,andalsoduring stopfeedingdurationitwasdifficulttotakeastoolsample. Itwasconcludedthatpretermwithfeedingintolerance hadstatisticallysignificantelevatedlevelsofFCPcompared topreterminfantswithoutfeedingintolerance.

Conflicts

of

interest

Theauthorsdeclarenoconflictsofinterest.

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