Newborn screening for mucopolysaccharidoses: A pilot study of 2,640 samples

Abstracts / Molecular Genetics and Metabolism 117 (2016) S14–S124

ambulatory status, medical history, Tanner score, and laboratory results were evaluated. In the 3 patients analyzed in this study (2 females) the mean age was 26.9 years. All patients were full-time ambulators. Two traumatic fractures were reported in a patient. WB and hip scans could not be obtained due to presence of prosthetic hip hardware, and only one LS scan was technically valid with normal Z-score (Z-score = -0.8). LDF scans were valid for all the patients. LDF Z-score was low at all regions analyzed with average for R1 = -3.1, R2 = -2.3, R3 = -2.1. In conclusion, patients with Morquio syndrome type B have low BMD of the lower extremities irrespective of ambulatory status. Patients did not experience low-energy fractures despite low BMD. The LDF is the most feasible measurement in patients with skeletal dysplasias. doi:10.1016/j.ymgme.2015.12.324

167 Hematopoietic stem cell transplantation and ERT for Hunter syndrome Francyne Kubaskia, Aratrik Guhaa, Yasuyuki Suzukib, Akemi Tanakac, Hiromasa Yabed, Li Xiee, Tor Gunnar Hugo Onstenf, Sandra LeistnerSegalf, Roberto Giuglianif, Robert W. Masona, Kenji E. Oriig, Haruo Shintakuc, Tadao Oriib, Shunji Tomatsuh, aUniversity of Delaware, Newark, DE, United States, bGifu University, Gifu, Japan, cOsaka City University, Osaka, Japan, dTokai University School of Medicine, Isehara, Japan, eNemours/ Alfred I.duPont Childre Hospital, Wilmington, DE, United States, fHospital de Clinicas de Porto Alegre, Porto Alegre, Brazil, g Gifu University Hospital, Gifu, Japan, hNemours/Alfred I.duPont Children Hospital, Wilmington, DE, United States To elucidate the impact of hematopoietic stem cell transplant (HSCT) and enzyme replacement therpay (ERT) in patients affected with Hunter syndrome, dried blood spots (DBS) from 78 subjects with Hunter syndrome (HSCT 4 and 17, and ERT 17 and 27 for attenuated, and severe phenotype, respectively, and 13 untreated patients) were analyzed for heparan sulfate (NS and OS) and keratan sulfate (mono and di) compared to 15 normal controls by liquid chromatography mass spectrometry (LC-MS/MS). Activity of daily living (ADL) was analyzed in treated patients. Average of HSCT patients was 15.2 years and 11.5 range: 2.5-25.4 (severe and attenuated phenotype respectively) while for ERT treated patients was 19.9 and 14 range: 3.7 to 40.7 (severe and attenuated phenotype respectively). HSCT had a better improvement compared to ERT regardless of phenotype. For HS-NS the average for untreated patients was 25 ng/ml while ERT attenuated was 11.5 ng/ml (p = 0.023) and severe was 11.3 ng/ml (p = 0.021) x 4.7 ng/ml for HSCT attenuated (p = 0.011) and 7.7 ng/ml for HSCT severe (p = 0.005). For HS-0S untreated patients had an average of 102.4, ERT attenuated 42.5 ng/ml (p = 0.005), 44.6 ng/ml ERT severe (p = 0.006) x 26.5 HSCT attenuated (p = 0.013) and 28.5 for HSCT severe (p = 0.001). For mono-sulfated KS average for untreated patients was 299.5 ng/ml, 294.7 for ERT attenuated, 309.3 for ERT severe, 207 for HSCT attenuated and 225.5 for HSCT severe. For disulfated KS untreated patients had an average of 108.9 ng/ml, ERT attenuated 136 ng/ml, 140.5 ng/ml ERT severe, 74.1 HSCT attenuated and 93.9 HSCT severe. HSCT severe phenotype patients had higher ADL scores than ERT severe patients. Our data shows the decrease in GAG levels compared with untreated and ERT-treated patients. In conclusion, our findings bring the urge for a discussion in the use of a therapy that was previously not recommended in the guidelines for treatment of Hunter syndrome, but which might be safe and successful when realized in young patients. doi:10.1016/j.ymgme.2015.12.325

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168 Newborn screening for mucopolysaccharidoses: A pilot study of 2,640 samples Francyne Kubaskia, Robert W. Masona, Roberto Giuglianib, Junji Hanaic, Li Xied, Naomi N. van Vliese, Heather Churchf, Seiji Yamaguchig, Yasuyuki Suzukih, Tadao Oriih, Adriana M. Montanoi, Shunji Tomatsud, a University of Delaware, Newark, DE, United States, bHospital de Clinicas de Porto Alegre, Porto Alegre, Brazil, cSapporo City Institute, Sapporo, Japan, dNemours/ Alfred I.duPont Children Hospital, Wilmington, DE, United States, eUniversity of Amsterdam, Amsterdam, Netherlands, f St Mary`s Hospital, Manchester, United Kingdom, gShimane University, Izumo, Japan, hGifu University, Gifu, Japan, iUniversity of Saint Louis, Saint Louis, MO, United States Mucopolysaccharidoses (MPS) have an estimated combined incidence of 1 in 22,000 live births. Specific treatment is already available for several MPS, and outcomes of therapy are generally better when treatment is started early. Thus, early diagnosis will improve both treatment and prognosis. The current study is a pilot study with 2,640 samples for newborn screening of MPS. Dried blood spots (DBS) from controls (2,640) or newborn MPS patients (MPS I = 6, MPS II = 2, MPS III = 5) were evaluated by specific enzyme digestion of DBS with heparitinase and keratanase to produce disaccharides that were analyzed by liquid chromatography mass spectrometry to determine levels of heparan sulfate (0S, NS) and keratan sulfate (mono-KS, di-KS and ratio di-KS/total KS). Cutoff levels to distinguish MPS from unaffected control individuals were established for HS. The average values for each subclass of HS in controls was HS-0S = 37 ng/ml (+50), HS-NS = 12 ng/ml (+28), mono-KS = 154 ng/ml (+168), di-KS = 35 ng/ml (+38), ratio di-KS in total KS = 18% (+9). Average for MPS patients for HS-0S = 201 ng/ml (+57), HS-NS: 60 ng/ml (+17), monoKS = 206 ng/ml (+125), di-KS = 64 ng/ml (+35), ratio di-KS in total KS = 26% (+ 12). Cutoffs were defined as mean + 2SD from newborn control samples (HS-0S N 137 ng/ml, HS-NS N 67 ng/ml). 2% and 6% of the controls, respectively, were higher than these values. As previous studies had reported, we also found increased KS levels in MPS I, II, and III (p = 0.02). We conclude that HS-0S (98% specificity and 77% sensitivity) and ratio di-KS in total KS are potential biomarkers for the newborn screening of newborn of MPS I, II, and III. doi:10.1016/j.ymgme.2015.12.326

169 Hematopoietic stem cell transplantation in Morquio syndrome type A Francyne Kubaskia, Robert W. Masona, Suzuki Yasuyukib, Shunji Tomatsuc, aUniversity of Delaware, Newark, DE, United States, bGifu University, Gifu, Japan, cNemours/ Alfred I.duPont Children Hospital, Wilmington, DE, United States Little has been known about the outcome of hematopoietic stem cell transplantation (HSCT) for Morquio syndrome type A, which stores keratan sulfate (KS). To understand whether blood KS level is reduced by HSCT in Morquio syndrome type A, KS levels (monosulfated KS, di-sulfated KS and ratio di-sulfated KS in total KS) DBS were measured by liquid chromatography tandem mass spectrometry (LC-MS/MS) in two patients with HSCT (attenuated and severe phenotype, respectively) compared with 6 untreated patients and 15 healthy control subjects (over 20 years of age). Both patients were transplanted at 15 years of age, and the DBS specimens were