Featured Publications
Invasive Pneumococcal Disease After 2 Decades of Pneumococcal Conjugate Vaccine Use.
Yildirim I, Lapidot R, Shaik-Dasthagirisaheb Y, Hinderstein S, Lee H, Klevens M, Grant L, Arguedas Mohs A, Cane A, Madoff L, Johnson H, Ivanof C, Burns M, Pelton S. Invasive Pneumococcal Disease After 2 Decades of Pneumococcal Conjugate Vaccine Use. Pediatrics 2023, 153 PMID: 38087952, DOI: 10.1542/peds.2023-063039.Peer-Reviewed Original ResearchConceptsInvasive pneumococcal diseaseIPD casesPCV13 eraPneumococcal diseaseCases of IPDIncidence of IPDRates of IPDPneumococcal conjugate vaccine useSerotype 15B/CImplementation of PCV13Non-PCV13 serotypesPneumococcal conjugate vaccineConfidence intervalsStatewide surveillance systemIPD incidence ratesIPD ratesPenicillin nonsusceptibilityConjugate vaccineVaccine serotypesSerotype 19ASterile sitesIncidence rateVaccine useLower incidenceVaccine formulations
2024
BK polyomavirus DNAemia, allograft rejection, and de novo donor‐specific antibodies after lowering target tacrolimus levels in pediatric kidney transplant recipients
Huang H, Xiang Y, George R, Winterberg P, Serluco A, Liverman R, Yildirim I, Garro R. BK polyomavirus DNAemia, allograft rejection, and de novo donor‐specific antibodies after lowering target tacrolimus levels in pediatric kidney transplant recipients. Pediatric Transplantation 2024, 28: e14791. PMID: 38808701, DOI: 10.1111/petr.14791.Peer-Reviewed Original ResearchConceptsDe novo donor-specific antibodiesTarget tacrolimus levelsDevelopment of de novo donor-specific antibodiesBiopsy-proven rejectionDonor-specific antibodiesMonths post-KTTacrolimus levelsTime of transplantationPediatric KT recipientsBK polyomavirusBKV-DNAemiaPost-KTPost-intervention cohortAllograft rejectionRecipient ageKT recipientsKidney transplantationPediatric kidney transplant recipientsLow tacrolimus levelsReduction of immunosuppressionKaplan-Meier survival analysisYounger recipient ageIndividualized immunosuppressive regimensKidney transplant recipientsRetrospective chart reviewDevelopment and comparison of immunologic assays to detect primary RSV infections in infants
Anderson L, Jadhao S, Hussaini L, Ha B, McCracken C, Gibson T, Yildirim I, Yi J, Stephens K, Korski C, Kao C, Sun H, Lee C, Jaunarajs A, Rostad C, Anderson E. Development and comparison of immunologic assays to detect primary RSV infections in infants. Frontiers In Immunology 2024, 14: 1332772. PMID: 38283339, PMCID: PMC10811012, DOI: 10.3389/fimmu.2023.1332772.Peer-Reviewed Original ResearchConceptsRespiratory syncytial virusIgG enzyme immunoassayNeutralizing antibody assaysELISPOT assayAntibody assayRSV antibodiesEnzyme immunoassayRSV infectionSubgroup ARespiratory syncytial virus seasonDocumented RSV infectionPrimary RSV infectionEffective respiratory syncytial virusVaccine clinical trialsEvidence of past infectionEpidemiological studiesRed cell lysisYoung childrenMaternal microchimerismPBMC specimensPregnant womenIFN-gSyncytial virusAntibody enzyme immunoassayELISPOT
2021
Respiratory Syncytial Virus–Associated Mortality Among Young Infants in Karachi, Pakistan: A Prospective Postmortem Surveillance Study
Kazi AM, Aguolu OG, Mughis W, Ahsan N, Jamal S, Khan A, Qureshi HM, Yildirim I, Malik FA, Omer SB. Respiratory Syncytial Virus–Associated Mortality Among Young Infants in Karachi, Pakistan: A Prospective Postmortem Surveillance Study. Clinical Infectious Diseases 2021, 73: s203-s209. PMID: 34472574, PMCID: PMC8411247, DOI: 10.1093/cid/ciab488.Peer-Reviewed Original ResearchConceptsRespiratory syncytial virusRespiratory symptomsInfant deathRSV seasonalityRole of RSVYoung infantsPresence of RSVMultivariable logistic regression analysisMaternal immunization strategiesSignificant mortality burdenVaccine-hesitant populationYoung infant deathsMultivariable logistic regressionCold-like symptomsSignificant predictorsLogistic regression analysisPostneonatal ageRSV mortalityRSV seasonMaternal immunizationInfant morbidityNasopharyngeal specimensNasopharyngeal swabsSyncytial virusRespiratory illnessA Retrospective Test-Negative Case-Control Study to Evaluate Influenza Vaccine Effectiveness in Preventing Hospitalizations in Children
Yildirim I, Kao CM, Tippett A, Suntarattiwong P, Munye M, Yi J, Elmontser M, Quincer E, Focht C, Watson N, Bilen H, Baker JM, Lopman B, Hogenesch E, Rostad CA, Anderson EJ. A Retrospective Test-Negative Case-Control Study to Evaluate Influenza Vaccine Effectiveness in Preventing Hospitalizations in Children. Clinical Infectious Diseases 2021, 73: 1759-1767. PMID: 34410341, PMCID: PMC8599178, DOI: 10.1093/cid/ciab709.Peer-Reviewed Original ResearchConceptsInfluenza vaccine effectivenessInfluenza-positive casesInfluenza-related hospitalizationsVaccine effectivenessInfluenza seasonOdds ratioInfluenza ALaboratory-confirmed influenza-related hospitalizationsTest-negative case-control study designAdjusted vaccine effectivenessInfluenza-negative controlsTest-negative controlsCase-control study designHospitalization of childrenTest-negative casesConfidence intervalsNon-Hispanic blacksLogistic regression modelsPreventing HospitalizationInfluenza vaccinationInfluenza burdenMedian ageInfluenza B.Influenza infectionPediatric hospitalizationsSafety, Tolerability, and Population Pharmacokinetics of Intravenous and Oral Isavuconazonium Sulfate in Pediatric Patients
Arrieta AC, Neely M, Day JC, Rheingold SR, Sue PK, Muller WJ, Danziger-Isakov LA, Chu J, Yildirim I, McComsey GA, Frangoul HA, Chen TK, Statler VA, Steinbach WJ, Yin DE, Hamed K, Jones ME, Lademacher C, Desai A, Micklus K, Phillips DL, Kovanda LL, Walsh TJ. Safety, Tolerability, and Population Pharmacokinetics of Intravenous and Oral Isavuconazonium Sulfate in Pediatric Patients. Antimicrobial Agents And Chemotherapy 2021, 65: 10.1128/aac.00290-21. PMID: 34031051, PMCID: PMC8284446, DOI: 10.1128/aac.00290-21.Peer-Reviewed Original ResearchConceptsPhase 1 studyPediatric patientsIsavuconazonium sulfatePlasma drug exposureDrug exposureOral administrationImmunocompromised Pediatric PatientsNew triazole agentProdrug isavuconazonium sulfateTolerability of isavuconazoleBody mass indexPopulation PK modelInvasive fungal infectionsProbability of targetTarget rangeConcentration-time curveFirst-order inputMass indexPopulation pharmacokineticsStepwise covariate modelingTriazole agentsClinical dosePK parametersLinear eliminationPatientsClinical Epidemiology and Outcomes of Pediatric Musculoskeletal Infections
Yi J, Wood JB, Creech CB, Williams D, Jimenez-Truque N, Yildirim I, Sederdahl B, Daugherty M, Hussaini L, Munye M, Tomashek KM, Focht C, Watson N, Anderson EJ, Thomsen I. Clinical Epidemiology and Outcomes of Pediatric Musculoskeletal Infections. The Journal Of Pediatrics 2021, 234: 236-244.e2. PMID: 33771580, PMCID: PMC8238832, DOI: 10.1016/j.jpeds.2021.03.028.Peer-Reviewed Original ResearchMeSH KeywordsAcute DiseaseAdministration, OralAdolescentAnti-Bacterial AgentsArthritis, InfectiousChildChild, PreschoolCombined Modality TherapyFemaleGram-Negative Bacterial InfectionsGram-Positive Bacterial InfectionsHumansInfantLogistic ModelsMaleMethicillin-Resistant Staphylococcus aureusOrthopedic ProceduresOsteomyelitisRetrospective StudiesStaphylococcal InfectionsTreatment OutcomeUnited StatesConceptsOsteomyelitis/septic arthritisAcute hematogenous osteomyelitisMethicillin-resistant S aureusSeptic arthritisHematogenous osteomyelitisTreatment failureS aureusOral therapyAntibiotic therapyMusculoskeletal infectionsHigher oddsPediatric musculoskeletal infectionsLonger hospital stayOral antibiotic therapyRetrospective cohort studyTreatment-related complicationsTreatment-associated complicationsHospital stayPediatric infectionsCohort studyParenteral therapyTreatment complicationsIntensive careRecurrent infectionsWorse outcomes
2020
Vaccine‐induced protection against hepatitis B in pediatric solid organ transplant patients
Ball M, Liverman R, Serluco A, Yildirim I. Vaccine‐induced protection against hepatitis B in pediatric solid organ transplant patients. Pediatric Transplantation 2020, 25: e13920. PMID: 33217081, DOI: 10.1111/petr.13920.Peer-Reviewed Original ResearchConceptsVaccine-induced protectionPediatric solid organ transplant patientsSolid organ transplant patientsOrgan transplant patientsHepatitis B virusHBV vaccinationTransplant patientsHepatitis B surface antibody titerHBV vaccination coverageHBV vaccine seriesPediatric SOT recipientsDetailed chart reviewYears of ageHBsAb titersSeroprotection ratesSOT recipientsHBV infectionTransplanted childrenVaccine seriesChart reviewHepatitis BLaboratory featuresImmunogenicity dataVaccination coverageVaccine immunityRecognition and Outcomes of Pneumococcal Meningitis in 2 Tertiary Pediatric Hospitals Since the Introduction of the 13-Valent Pneumococcal Conjugate Vaccine
Stevens JP, Lively A, Jerris R, Yildirim I, Lantis P. Recognition and Outcomes of Pneumococcal Meningitis in 2 Tertiary Pediatric Hospitals Since the Introduction of the 13-Valent Pneumococcal Conjugate Vaccine. Pediatric Emergency Care 2020, 38: e354-e359. PMID: 33181795, DOI: 10.1097/pec.0000000000002288.Peer-Reviewed Original ResearchConceptsPneumococcal conjugate vaccineLumbar puncturePneumococcal meningitisConjugate vaccineMeningeal signsLow suspicionMental statusPositive cerebrospinal fluid culturesLonger hospital lengthStreptococcus pneumoniae meningitisCerebrospinal fluid culturesCranial nerve palsyHours of admissionTertiary pediatric hospitalPoor clinical outcomeTertiary healthcare systemPneumococcal meningitis casesPneumococcal immunizationPneumoniae meningitisHospital lengthNerve palsyPrimary outcomeAntibiotic administrationClinical outcomesPediatric hospitalThe burden of respiratory syncytial virus infections among children with sickle cell disease
Rostad CA, Maillis AN, Lai K, Bakshi N, Jerris RC, Lane PA, Yee ME, Yildirim I. The burden of respiratory syncytial virus infections among children with sickle cell disease. Pediatric Blood & Cancer 2020, 68: e28759. PMID: 33034160, PMCID: PMC8246443, DOI: 10.1002/pbc.28759.Peer-Reviewed Original ResearchConceptsRespiratory syncytial virusSickle cell diseaseRespiratory viral panelRSV-positive casesRSV infectionAnnual incidenceHospitalization ratesCell diseaseBurden of RSVPediatric lower respiratory tract infectionsLaboratory-confirmed RSV infectionRespiratory syncytial virus infectionRSV-related hospitalization rateLower respiratory tract infectionsRSV positive testRSV-negative childrenRSV-negative patientsAcute chest syndromeSyncytial virus infectionRespiratory tract infectionsAverage annual incidenceMultivariate logistic regressionConfidence intervalsCase-control studyOutcome of childrenMicrobiology and radiographic features of osteomyelitis in children and adolescents with sickle cell disease
Kao CM, Yee ME, Maillis A, Lai K, Bakshi N, Rostad BS, Jerris RC, Lane PA, Yildirim I. Microbiology and radiographic features of osteomyelitis in children and adolescents with sickle cell disease. Pediatric Blood & Cancer 2020, 67: e28517. PMID: 32710705, PMCID: PMC8369475, DOI: 10.1002/pbc.28517.Peer-Reviewed Original ResearchConceptsSickle cell diseaseMethicillin-susceptible Staphylococcus aureusMagnetic resonance imagingAntibiotic treatmentOperative culturesCell diseaseLarge tertiary pediatric centerPrescribed antibiotic treatmentTertiary pediatric centerCulture-positive casesKey presenting symptomsChildren ages 6Bone painMicrobiologic etiologyPresenting symptomPediatric centersBone infarctsMedical chartsMicrobiologic findingsRadiographic featuresImaging featuresOsteomyelitisProbable osteomyelitisDiagnostic codingTissue debridementBrincidofovir for the treatment of human adenovirus infection in pediatric solid organ transplant recipients: A case series
Londeree J, Winterberg PD, Garro R, George RP, Shin S, Liverman R, Serluco A, Romero R, Yildirim I. Brincidofovir for the treatment of human adenovirus infection in pediatric solid organ transplant recipients: A case series. Pediatric Transplantation 2020, 24: e13769. PMID: 32558134, DOI: 10.1111/petr.13769.Peer-Reviewed Original ResearchConceptsPediatric SOT recipientsSOT recipientsCase seriesSevere diseasePediatric solid organ transplant recipientsSolid organ transplant recipientsType of allograftMainstay of treatmentOrgan transplant recipientsSeverity of diseaseHuman adenovirus infectionHAdV diseaseHAdV viremiaPediatric recipientsTransplant recipientsHAdV infectionDisease courseAntiviral therapySignificant morbidityDisease presentationUS FDAAdenovirus infectionBrincidofovirDiseaseRecipientsInfluenza vaccine effectiveness and disease burden in children and adolescents with sickle cell disease: 2012‐2017
Kao CM, Lai K, McAteer JM, Elmontser M, Quincer EM, Yee MEM, Tippet A, Jerris RC, Lane PA, Anderson EJ, Bakshi N, Yildirim I. Influenza vaccine effectiveness and disease burden in children and adolescents with sickle cell disease: 2012‐2017. Pediatric Blood & Cancer 2020, 67: e28358. PMID: 32469138, PMCID: PMC8221251, DOI: 10.1002/pbc.28358.Peer-Reviewed Original ResearchConceptsInfluenza vaccine effectivenessSickle cell diseaseVaccine effectivenessYears of ageInfluenza infectionOdds ratioCell diseaseLaboratory-confirmed influenza infectionSeasonal influenza vaccine effectivenessTest-negative case-control study designAdjusted vaccine effectivenessAdjusted VE estimatesInfluenza-positive casesOverall vaccine effectivenessAcute chest syndromeBurden of influenzaPatients 6 monthsMulticenter prospective studyTest-negative controlsAnnual influenza vaccineCase-control study designConfidence intervalsLogistic regression modelsChest syndromeInfluenza seasonUrinary Tract Infections With Extended-spectrum-β-lactamase-producing Bacteria: Case-control Study.
Amin O, Prestel C, Gonzalez MD, Lyon T, Shane A, Jaggi P, Tippett A, Yildirim I. Urinary Tract Infections With Extended-spectrum-β-lactamase-producing Bacteria: Case-control Study. The Pediatric Infectious Disease Journal 2020, 39: 211-216. PMID: 32032306, DOI: 10.1097/inf.0000000000002531.Peer-Reviewed Original ResearchConceptsUrinary tract infectionESBL-producing bacteriaCase-control studyRisk factorsTract infectionsPrior intensive care unit admissionIntensive care unit admissionPediatric urinary tract infectionCause of UTIClinical signs/symptomsCare unit admissionIndependent risk factorYear of diagnosisΒ-lactamase-producing bacteriaSigns/symptomsCommon bacterial infectionsSpectrum β-lactamasesRational antimicrobial useESBL casesESBL-UTIUnit admissionUnderlying comorbiditiesPrior hospitalizationEmpirical therapyPediatric patientsWho is at risk of 13-valent conjugated pneumococcal vaccine failure?
Yildirim M, Keskinocak P, Pelton S, Pickering L, Yildirim I. Who is at risk of 13-valent conjugated pneumococcal vaccine failure? Vaccine 2020, 38: 1671-1677. PMID: 31974018, DOI: 10.1016/j.vaccine.2019.12.060.Peer-Reviewed Original ResearchConceptsInvasive pneumococcal diseaseVaccine failureIPD casesVaccine serotypesDiagnosis of IPDHigh vaccine coverage ratesPneumococcal conjugate vaccineVaccine coverage ratesUnderlying risk factorsYears of ageMonths of agePneumococcal pneumoniaImmunization PracticesVaccine scheduleConjugate vaccinePneumococcal diseasePrimary dosesClinical presentationImmunization scheduleSerotype 19ACourse of immunisationRisk factorsComorbiditiesStudy periodPassive surveillance
2019
Assessment and Validation of Syndromic Case Definitions for Respiratory Syncytial Virus Infections in Young Infants: A Latent Class Analysis.
Lalani K, Yildirim I, Phadke VK, Bednarczyk RA, Omer SB. Assessment and Validation of Syndromic Case Definitions for Respiratory Syncytial Virus Infections in Young Infants: A Latent Class Analysis. The Pediatric Infectious Disease Journal 2019, 38: 1177-1182. PMID: 31568250, DOI: 10.1097/inf.0000000000002468.Peer-Reviewed Original ResearchConceptsRespiratory syncytial virusSyndromic case definitionsCase definitionYoung infantsWorld Health OrganizationRSV infectionLatent class analysisPredictive valueLaboratory-confirmed RSV infectionRespiratory syncytial virus infectionSyncytial virus infectionAcute respiratory infectionsHigh positive predictive valueRoutine clinical careStandardized case definitionsHigh-resource settingsAppropriate case definitionsHigh-income settingsNegative predictive valueMonths of agePositive predictive valueRespiratory infectionsVaccine evaluationClinical featuresPediatric morbidityIncidence of invasive Haemophilus influenzae infections in children with sickle cell disease
Yee ME, Bakshi N, Graciaa SH, Lane PA, Jerris RC, Wang YF, Yildirim I. Incidence of invasive Haemophilus influenzae infections in children with sickle cell disease. Pediatric Blood & Cancer 2019, 66: e27642. PMID: 30724001, PMCID: PMC6472970, DOI: 10.1002/pbc.27642.Peer-Reviewed Original ResearchConceptsSickle cell diseaseComprehensive clinical databaseInfluenzae infectionAntibiotic prophylaxisInfluenzae diseaseInvasive infectionsCell diseaseInvasive Haemophilus influenzae infectionsPediatric tertiary care centerHaemophilus influenzae type bLarge pediatric tertiary care centerUniversal antibiotic prophylaxisSterile body fluid culturesTertiary care centerHaemophilus influenzae infectionsBody fluid culturesInfluenzae type bYears of ageDistribution of serotypesNonvaccine serotypesClinical featuresOverall incidenceCare centerFluid cultureIncidence rate
2018
Impact of Pharmacy-Initiated Interventions on Influenza Vaccination Rates in Pediatric Solid Organ Transplant Recipients
Gattis S, Yildirim I, Shane AL, Serluco S, McCracken C, Liverman R. Impact of Pharmacy-Initiated Interventions on Influenza Vaccination Rates in Pediatric Solid Organ Transplant Recipients. Journal Of The Pediatric Infectious Diseases Society 2018, 8: 525-530. PMID: 30307524, DOI: 10.1093/jpids/piy095.Peer-Reviewed Original ResearchConceptsSolid organ transplant recipientsPediatric SOT recipientsInfluenza vaccination ratesOrgan transplant recipientsSOT recipientsTransplant recipientsInfluenza infectionVaccination ratesVaccination coveragePediatric solid organ transplant recipientsSubsequent graft dysfunctionHeart transplant recipientsInfluenza vaccination coveragePre-post study designNumber of patientsRate of vaccinationGraft dysfunctionInfluenza immunizationInfluenza vaccinationChart reviewPharmacy interventionsMedian timeVaccine coverageTransplant servicesInfluenza ratesInfants at Risk for Invasive Pneumococcal Disease in the 13-Valent Pneumococcal Conjugate Vaccine Era
Yildirim I, Pelton SI. Infants at Risk for Invasive Pneumococcal Disease in the 13-Valent Pneumococcal Conjugate Vaccine Era. Clinical Infectious Diseases 2018, 69: 91-92. PMID: 30281070, DOI: 10.1093/cid/ciy848.Peer-Reviewed Original ResearchAssessment and Validation of Syndromic Case definitions for Respiratory Syncytial Virus Testing in a Low Resource Population
Omer SB, Bednarczyk R, Kazi M, Guterman LB, Aziz F, Allen KE, Yildirim I, Ali SA. Assessment and Validation of Syndromic Case definitions for Respiratory Syncytial Virus Testing in a Low Resource Population. The Pediatric Infectious Disease Journal 2018, Publish Ahead of Print: &na;. PMID: 30074977, PMCID: PMC6437080, DOI: 10.1097/inf.0000000000002159.Peer-Reviewed Original ResearchConceptsCommunity-based surveillanceCase definitionRespiratory syncytial virus testingRespiratory syncytial virus infectionSyncytial virus infectionLow-resource populationsStandardized case definitionsSyndromic case definitionsResource-limited settingsVaccine evaluationVirus infectionVirus testingYoung infantsVirus control strategiesModest specificitySurveillanceCyanosisWheezeApneaInfantsInfection