Abstract
Objective: Cystic fibrosis (CF) is an inherited disorder which has negative impact on life span and quality. Newbornscreening (NBS) is carried out by sweat chloride test (SCT) in babies with high immunoreactive trypsinogen (IRT) values.We aimed to present our data consisting of application and evaluation of sweat chloride test in babies referred to ourcenter with two elevated IRT levels following national NBS.
Material and Methods: This retrospective study evaluated clinical data, sweat chloride test and CF transmembraneregulator (CFTR) gene mutation analysis results of referred infants due to positive CF NBS between January 2015–January 2019. Sweat chloride test results were interpreted as normal (<30mmol/L), intermediate (30-59 mmol/L) or high(≥60mmol/L). Infants missing a second test despite an initial invalid result (<10 mmol/L) or inadequate sweat collectionwere not included.
Results: The study group consisted of 184 infants of female/male ratio as 113/71(61.4/38.6%). The median admissiontime was postnatal 26 (9-98) days. The mean gestational week was 39 ± 1.75 weeks and mean birth weight was 3300± 432 grams. All infants passed their first stool in 48 hours at most. Five infants (3.6%) faced prolonged jaundice andtwo (1.4%) had neonatal pneumonia. Weight gain was insufficient in seven (5%) infants. No infant showed physicalexamination findings consistent with CF. First SCT was normal (n=153, 83.1%), intermediate (n=9, 4.9%) or high (n=1,0.5%). Thirty-one infants had the second test because of inadequate sweat collection, invalid or high/intermediaterange initial result. Consequently, 178 infants (96.7%) reflected normal results. Repeated SCT was high (n=2, 1.1%)/intermediate (n=4, 2.2%) in six (3.3%) infants. CFTR mutation analysis revealed one homozygote F508 deletion andthree 5T/7T/9T polymorphisms. Three patients received treatment while three were conservatively followed-up.
Conclusion: NBS can provide early diagnosis of patients with CF if standardized implementation and careful interpretationof sweat chloride test are achieved. Sharing of data by centers performing sweat chloride test is extremely important for the assurance of interoperability of the system.
Keywords: cystic fibrosis, neonatal screening
References
- KAYNAKLAR: 1) Boyle MP, De Boeck K. A new era in the treatment of cystic fibrosis: correction of the underlying CFTR defect. Lancet Respir Med. 2013;1(2):158-63.
- 2) Cystic Fibrosis Mutation Database. http://www.genet.sickkids.on.ca/Home.htlm2013. Accessed Jan 14, 2019.
- 3) Southern KW, Munck A, Pollitt R, Travert G, Zanolla L, Dankert-Roelse J, et al. A survey of newborn screening for cystic fibrosis in Europe. J Cyst Fibros. 2007;6:57–65.
- 4) Uslu HS, Zübarioğlu AU, Bülbül A. Neonatoloji Perspektifinden Selektif Metabolik Tarama Testleri. Selective Metabolic Screening from a Neonatology Perspective. JAREM 2015; 5: 39-46.
- 5) Paranjape SM, Mogayzel PJ Jr. Cystic fibrosis. Pediatr Rev. 2014;35(5):194-205.
- 6) Türk Toraks Derneği Kistik Fibrozis Tanı ve Tedavi Rehberi. Türk Toraks Dergisi 2011; 12:2. https://www.toraks.org.tr/book.aspx?list=1078&menu=222&menu=222
- 7) Farrell PM, White TB, Howenstine MS, Munck A, Parad RB, Rosenfeld M, et al. Diagnosis of Cystic Fibrosis in Screened Populations. J Pediatr. 2017;181S:S33-S44.e2.
- 8) Cystic Fibrosis Foundation. 2012 Annual Data Report. Bethesda, MD: Cystic Fibrosis Foundation Patient Registry; 2013.
- 9) Farrell PM, Rosenstein BJ, White TB, Accurso FJ, Castellani C, Cutting GR, et al. Guidelines for diagnosis of cystic fibrosis in newborns through older adults: Cystic Fibrosis Foundation consensus report.3rd; Cystic Fibrosis Foundation.J Pediatr. 2008;153(2):S4-S14
- 10) Therrell BL Jr, Hannon WH, Hoffman G, Ojodu J, Farrell PM. Immunoreactive Trypsinogen (IRT) as a Biomarker for Cystic Fibrosis: challenges in newborn dried blood spot screening. Mol Genet Metab. 2012;106(1):1-6.
- 11) T.C. Sağlık Bakanlığı Türkiye Halk Sağlığı Kurumu. Kistik fibrozis yenidoğan tarama testi ile tanı alan hastaları izleme rehberi, 2015 (Çocuk Solunum Yolu Hastalıkları ve Kistik Fibrozis Derneği, Çocuk Göğüs Hastalıkları Derneği) http://kistikfibrozisturkiye.org/2017/files/admin/KF_yenidogan_tarama_rehberi.pdf
- 12) Gibson Le, Cooke Re. A test for concentration of electrolytes in sweat in cystic fibrosis of the pancreas utilizing pilocarpine by iontophoresis. Pediatrics 1959;23(3):545-9.
- 13) Lezana JL, Vargas MH, Karam-Bechara J, Aldana RS, Furuya ME. Sweat conductivity and chloride titration for cystic fibrosis diagnosis in 3834 subjects. J Cyst Fibros. 2003;2(1):1-7.
- 14) Baumer JH. Evidence-based guidelines for the performance of the sweat test for the investigation of cystic fibrosis in the UK. Arch Dis Child. 2003;88(12):1126-7.
- 15) Crossley JR, Elliott RB, Smith PA. Dried-blood spot screening for cystic fibrosis in the newborn. Lancet. 1979;1(8114):472-4.
- 16) Wagener JS, Zemanick ET, Sontag MK. Newborn screening for cystic fibrosis. Curr Opin Pediatr. 2012;24(3):329-35.
- 17) Grosse SD, Boyle CA, Botkin JR, Comeau AM, Kharrazi M, Rosenfeld M, et al; CDC. Newborn screening for cystic fibrosis: evaluation of benefits and risks and recommendations for state newborn screening programs. MMWR Recomm Rep. 2004;53(RR-13):1-36.
- 18) Cystic Fibrosis Foundation. Cystic Fibrosis Foundation Patient Registry 2014 annual data report. Bethesda (MD): Cystic Fibrosis Foundation; 2015. https://www.cff.org/Our-Research/CF-Patient-Registry/2015-Patient-Registry-Annual-Data-Report.pdf
- 19) Üstü Y, Uğurlu M. Ulusal Erken Tanı ve Tarama Programı: Kistik Fibrozis National Early Diagnosis and Screening Program: Cystic Fibrosis Ulusal Erken Tanı ve Tarama Programı: Kistik Fibrozis National Early Diagnosis and Screening Program: Cystic Fibrosis. Ankara Med J, 2016;16(2):239-41.
- 20) Salvatore D, Buzzetti R, Baldo E, Forneris MP, Lucidi V, Manunza D, et al. An overview of international literature from cystic fibrosis registries 2. Neonatal screening and nutrition/growth. J Cyst Fibros. 2010;9(2):75-83.
- 21) Rosenfeld M, Sontag MK, Ren CL. Cystic Fibrosis Diagnosis and Newborn Screening.Pediatr Clin North Am. 2016;63(4):599-615.
- 22) Southern KW, Merelle MM, Dankert-Roelase JE, Nagelkerke AD. Newborn screening for cystic fibrosis. Cochrane Database Syst Rev 2009; (1): CD001402.
- 23) Tluczek A, Becker T, Laxova A, Grieve A, Gilles CNR, Rock MJ, et al. Relationships among health-related quality of life, pulmonary health and newborn screening for cystic fibrosis. Chest 2011; 140: 170-177.
- 24) Rosenfeld M, Emerson J, McNamara S, Joubran K, Retsch-Bogart G, Graff GR, et al. Baseline characteristics and factors associated with nutritional and pulmonary status at enrollment in the cystic fibrosis EPIC observational cohort. Pediatr Pulmonol 2010; 45: 934-944.
- 25) Dijk FN, McKay K, Barzi F, Gaskin KJ, Fitzgerald DA. Improved survival in cystic fibrosis patients diagnosed by newborn screening compared to a historical cohort from the same centre. Arch Dis Child 2011;96(12):1118-23.
- 26) Castellani C, Massie J, Sontag M, Southern KW. Newborn screening for cystic fibrosis. Lancet Respir Med. 2016;4(8):653-661.
- 27) Sims EJ, Mugford M, Clark A, Aitken D, McCormick J, Mehta G, et al, and the UK Cystic Fibrosis Database Screening Committee. Economic implications of newborn screening for cystic fibrosis: a cost of illness retrospective cohort study. Lancet 2007; 369: 1187-95.
- 28) Cystic fibrosis Trust. UK Cystic Fibrosis Registry annual data report 2016. 2017. https://www.cysticfibrosis.org.uk/the-work-we-do/uk-cf-registry/reporting-and-resources
- 29) McColley SA, Michelson P, Petren K. A state level registry report for assessment of cystic fibrosis newborn screening programs. Pediatr Pulmonol 2014; 49 (S38): S383.
- 30) Groves T, Robinson P, Fitzgerald DA. Question 7: For an infant with an equivocal sweat chloride following newborn screening, how likely is a diagnosis of cystic fibrosis? Paediatr Respir Rev. 2016;20:48-50.
- 31) Salinas DB, Azen C, Young S, Keens TG, Kharrazi M, Parad RB. Phenotypes of California CF Newborn Screen-Positive Children with CFTR 5T Allele by TG Repeat Length. Genet Test Mol Biomarkers. 2016;20(9):496-503.