Comparison of Fluorometric Immunoassay and Tandem Mass Spectrometry Methods Used in the Diagnosis of Phenylalanine Metabolism Disorders in Turkish Children


Kazanasmaz H., KARACA M.

ISTANBUL MEDICAL JOURNAL, cilt.20, sa.4, ss.279-284, 2019 (ESCI, TRDizin) identifier identifier

  • Yayın Türü: Makale / Tam Makale
  • Cilt numarası: 20 Sayı: 4
  • Basım Tarihi: 2019
  • Doi Numarası: 10.4274/imj.galenos.2019.53189
  • Dergi Adı: ISTANBUL MEDICAL JOURNAL
  • Derginin Tarandığı İndeksler: Emerging Sources Citation Index (ESCI), TR DİZİN (ULAKBİM)
  • Sayfa Sayıları: ss.279-284
  • Karadeniz Teknik Üniversitesi Adresli: Hayır

Özet

Introduction: Phenylketonuria is one of the common causes of preventable mental retardation. Therefore, dietary and/or cofactor therapy initiated by early detection of the disease is of great clinical importance. In this study, the specificity and sensitivity of fluorescence immunoassay (FIA), tandem mass spectrometry (MS/MS) and plasma amino acid analysis methods used in the diagnosis of phenylalanine metabolism disorder (PMD) were compared. Methods: Patients who were referred to our clinic with a prediagnosis of PMD disorder (n=163) from primary health care institutions were included in the study. Results: The median age of the patients on admission was 3 months (range: 0-25 months). It was observed that the samples were resent to the newborn screening program at a rate of 68.1%. The sensitivity and specificity of FIA for phenylalanine (Phe) with a cut-off value of 2.95 mg/dL were 73.3% and 78.6%, respectively. The sensitivity and specificity of MS/MS for Phe with a cut-off value of >= 94.94 mu mol/L were 93.3% and 92.2%, respectively. Conclusion: A clinical delay was detected in the diagnosis of the cases. Because of this clinical delay, it is considered that the samples in the screening program are repeated frequently and that families do not have enough information about the disease. In our study, it was shown that MS/MS was more effective than FIA. The use of MS/MS instead of FIA for the detection of phenylalanine metabolism disorder in the neonatal screening program may be effective in preventing the diagnostic delay.