Consensus guidelines for the monitoring and management of metachromatic leukodystrophy in the United States.

Metachromatic leukodystrophy (MLD) is a fatal, progressive neurodegenerative disorder caused by biallelic pathogenic mutations in the ARSA (Arylsulfatase A) gene. With the advent of presymptomatic diagnosis and the availability of therapies with a narrow window for intervention, it is critical to define a standardized approach to diagnosis, presymptomatic monitoring, and clinical care. To meet the needs of the MLD community, a panel of MLD experts was established to develop disease-specific guidelines based on healthcare resources in the United States. This group developed a consensus opinion for best-practice recommendations, as follows: (i) Diagnosis should include both genetic and biochemical testing; (ii) Early diagnosis and treatment for MLD is associated with improved clinical outcomes; (iii) The panel supported the development of newborn screening to accelerate the time to diagnosis and treatment; (iv) Clinical management of MLD should include specialists familiar with the disease who are able to follow patients longitudinally; (v) In early onset MLD, including late infantile and early juvenile subtypes, ex vivo gene therapy should be considered for presymptomatic patients where available; (vi) In late-onset MLD, including late juvenile and adult subtypes, hematopoietic cell transplant (HCT) should be considered for patients with no or minimal disease involvement. This document summarizes current guidance on the presymptomatic monitoring of children affected by MLD as well as the clinical management of symptomatic patients. Future data-driven evidence and evolution of these recommendations will be important to stratify clinical treatment options and improve clinical care.

Admixture mapping reveals evidence of differential multiple sclerosis risk by genetic ancestry.

Multiple sclerosis (MS) is an autoimmune disease with high prevalence among populations of northern European ancestry. Past studies have shown that exposure to ultraviolet radiation could explain the difference in MS prevalence across the globe. In this study, we investigate whether the difference in MS prevalence could be explained by European genetic risk factors. We characterized the ancestry of MS-associated alleles using RFMix, a conditional random field parameterized by random forests, to estimate their local ancestry in the largest assembled admixed population to date, with 3,692 African Americans, 4,915 Asian Americans, and 3,777 Hispanics. The majority of MS-associated human leukocyte antigen (HLA) alleles, including the prominent HLA-DRB1*15:01 risk allele, exhibited cosmopolitan ancestry. Ancestry-specific MS-associated HLA alleles were also identified. Analysis of the HLA-DRB1*15:01 risk allele in African Americans revealed that alleles on the European haplotype conferred three times the disease risk compared to those on the African haplotype. Furthermore, we found evidence that the European and African HLA-DRB1*15:01 alleles exhibit single nucleotide polymorphism (SNP) differences in regions encoding the HLA-DRB1 antigen-binding heterodimer. Additional evidence for increased risk of MS conferred by the European haplotype were found for HLA-B*07:02 and HLA-A*03:01 in African Americans. Most of the 200 non-HLA MS SNPs previously established in European populations were not significantly associated with MS in admixed populations, nor were they ancestrally more European in cases compared to controls. Lastly, a genome-wide search of association between European ancestry and MS revealed a region of interest close to the ZNF596 gene on chromosome 8 in Hispanics; cases had a significantly higher proportion of European ancestry compared to controls. In conclusion, our study established that the genetic ancestry of MS-associated alleles is complex and implicated that difference in MS prevalence could be explained by the ancestry of MS-associated alleles.

Consensus recommendations for the classification and long-term follow up of infants who screen positive for Krabbe Disease.

OBJECTIVE: To provide updated evidence and consensus-based recommendations for the classification of individuals who screen positive for Krabbe Disease (KD) and recommendations for long-term follow-up for those who are at risk for late onset Krabbe Disease (LOKD). METHODS: KD experts (KD NBS Council) met between July 2017 and June 2020 to develop consensus-based classification and follow-up recommendations. The resulting newly proposed recommendations were assessed in a historical cohort of 47 newborns from New York State who were originally classified at moderate or high risk for LOKD. RESULTS: Infants identified by newborn screening with possible KD should enter one of three clinical follow-up pathways (Early infantile KD, at-risk for LOKD, or unaffected), based on galactocerebrosidase (GALC) activity, psychosine concentration, and GALC genotype. Patients considered at-risk for LOKD based on low GALC activity and an intermediate psychosine concentration are further split into a high-risk or low-risk follow-up pathway based on genotype. Review of the historical New York State cohort found that the updated follow-up recommendations would reduce follow up testing by 88%. CONCLUSION: The KD NBS Council has presented updated consensus recommendations for efficient and effective classification and follow-up of NBS positive patients with a focus on long-term follow-up of those at-risk for LOKD.

"Here I can just be myself": How youth and adults collaboratively develop an identity-safe community across difference.

The aim of this study was to investigate the development of identity safety-where all participants are valued, included, and can engage without fear of stigmatization-among underrepresented youth and adults in a community-based youth development program. Qualitative in-depth interviews were conducted daily with three youth and two adult mentors about their experiences in the program (a total of 32 interviews). Data analysis revealed that participants developed identity safety through engaging in programmatic activities that explored youth's identities, practicing authenticity in daily interactions, and facilitating dynamic communication across intergenerational friendships. Participants described sustaining identity safety through formal social support spaces, mutual support in group settings, and peer support. Ultimately, these experiences set the foundation for youth and adults to engage in positive risk-taking and self-reflection. Implications for researchers and youth development programs are discussed.

Dietary factors and pediatric multiple sclerosis: A case-control study.

BACKGROUND: The role of diet in multiple sclerosis (MS) is largely uncharacterized, particularly as it pertains to pediatric-onset disease. OBJECTIVE: To determine the association between dietary factors and MS in children. METHODS: Pediatric MS patients and controls were recruited from 16 US centers (MS or clinically isolated syndrome onset before age 18, <4 years from symptom onset and at least 2 silent lesions on magnetic resonance imaging). The validated Block Kids Food Screener questionnaire was administered 2011-2016. Chi-squared test compared categorical variables, Kruskal-Wallis test compared continuous variables, and multivariable logistic regression analysis was performed. RESULTS: In total, 312 cases and 456 controls were included (mean ages 15.1 and 14.4 years). In unadjusted analyses, there was no difference in intake of fats, proteins, carbohydrates, sugars, fruits, or vegetables. Dietary iron was lower in cases ( p = 0.04), and cases were more likely to consume below recommended guidelines of iron (77.2% of cases vs 62.9% of controls, p < 0.001). In multivariable analysis, iron consumption below recommended guidelines was associated with MS (odds ratio = 1.80, p < 0.01). CONCLUSION: Pediatric MS cases may be less likely to consume sufficient iron compared to controls, and this warrants broader study to characterize a temporal relationship. No other significant difference in intake of most dietary factors was found.

Genetic risk factors for pediatric-onset multiple sclerosis.

BACKGROUND: Strong evidence supports the role of both genetic and environmental factors in pediatric-onset multiple sclerosis (POMS) etiology. OBJECTIVE: We comprehensively investigated the association between established major histocompatibility complex (MHC) and non-MHC adult multiple sclerosis (MS)-associated variants and susceptibility to POMS. METHODS: Cases with onset <18 years (n = 569) and controls (n = 16,251) were included from the United States and Sweden. Adjusted logistic regression and meta-analyses were performed for individual risk variants and a weighted genetic risk score (wGRS) for non-MHC variants. Results were compared to adult MS cases (n = 7588). RESULTS: HLA-DRB1*15:01 was strongly associated with POMS (odds ratio (OR)meta = 2.95, p < 2.0 × 10-16). Furthermore, 28 of 104 non-MHC variants studied (23%) were associated (p < 0.05); POMS cases carried, on average, a higher burden of these 28 variants compared to adults (ORavg = 1.24 vs 1.13, respectively), though the difference was not significant. The wGRS was strongly associated with POMS (ORmeta = 2.77, 95% confidence interval: 2.33, 3.32, p < 2.0 × 10-16) and higher, on average, when compared to adult cases. Additional class III risk variants in the MHC region associated with POMS were revealed after accounting for HLA-DRB1*15:01 and HLA-A*02. CONCLUSION: Pediatric and adult MS share many genetic variants suggesting similar biological processes are present. MHC variants beyond HLA-DRB1*15:01 and HLA-A*02 are also associated with POMS.

A Supply and Demand Management Perspective on the Accelerated Global Introductions of Inactivated Poliovirus Vaccine in a Constrained Supply Market.

A total of 105 countries have introduced IPV as of September 2016 of which 85 have procured the vaccine through UNICEF. The Global Eradication and Endgame Strategic Plan 2013-2018 called for the rapid introduction of at least one dose of IPV into routine immunization schedules in 126 all OPV-using countries by the end of 2015. At the time of initiating the procurement process, demand was estimated based on global modeling rather than individual country indications. In its capacity as procurement agency for the Global Polio Eradication Initiative and Gavi, the Vaccine Alliance, UNICEF set out to secure access to IPV supply for around 100 countries. Based on offers received, sufficient supply was awarded to two manufacturers to meet projected routine requirements. However, due to technical issues scaling up vaccine production and an unforecasted demand for IPV use in campaigns to interrupt wild polio virus and to control type 2 vaccine derived polio virus outbreaks, IPV supplies are severely constrained. Activities to stretch supplies and to suppress demand have been ongoing since 2014, including delaying IPV introduction in countries where risks of type 2 reintroduction are lower, implementing the multi-dose vial policy, and encouraging the use of fractional dose delivered intradermally. Despite these efforts, there is still insufficient IPV supply to meet demand. The impact of the supply situation on IPV introduction timelines in countries are the focus of this article, and based on lessons learned with the IPV introductions, it is recommended for future health programs with accelerated scale up of programs, to take a cautious approach on supply commitments, putting in place clear allocation criteria in case of shortages or delays and establishing a communication strategy vis a vis beneficiaries.

Managing the Planned Cessation of a Global Supply Market: Lessons Learned From the Global Cessation of the Trivalent Oral Poliovirus Vaccine Market.

The Polio Eradication and Endgame Strategic Plan 2013-2018 calls for the phased withdrawal of OPV, beginning with the globally synchronized cessation of tOPV by mid 2016. From a global vaccine supply management perspective, the strategy provided two key challenges; (1) the planned cessation of a high volume vaccine market; and (2) the uncertainty of demand leading and timeline as total vaccine requirements were contingent on epidemiology. The withdrawal of trivalent OPV provided a number of useful lessons that could be applied for the final OPV cessation. If carefully planned for and based on a close collaboration between programme partners and manufacturers, the cessation of a supply market can be undertaken with a successful outcome for both parties. As financial risks to manufacturers increase even further with OPV cessation, early engagement from the cessation planning phase and consideration of production lead times will be critical to ensure sufficient supply throughout to achieve programmatic objectives. As the GPEI will need to rely on residual stocks including with manufacturers through to the last campaign to achieve its objectives, the GPEI should consider to decide on and communicate a suitable mechanism for co-sharing of financial risks or other financial arrangement for the outer years.

Considerations for the Full Global Withdrawal of Oral Polio Vaccine After Eradication of Polio.

Eliminating the risk of polio from vaccine-derived polioviruses is essential for creating a polio-free world, and eliminating that risk will require stopping use of all oral polio vaccines (OPVs) once all types of wild polioviruses have been eradicated. In many ways, the experience with the global switch from trivalent OPV (tOPV) to bivalent OPV (bOPV) can inform the eventual full global withdrawal of OPV. Significant preparation will be needed for a thorough, synchronized, and full withdrawal of OPV, and such preparation would be aided by setting a reasonably firm date for OPV withdrawal as far in advance as possible, ideally at least 24 months. A shorter lead time would provide valuable flexibility for decisions about when to stop use of OPV in the context of uncertainty about whether or not all types of wild polioviruses had been eradicated, but it might increase the cost of OPV withdrawal.

Implementing the Synchronized Global Switch from Trivalent to Bivalent Oral Polio Vaccines-Lessons Learned From the Global Perspective.

In 2015, the Global Commission for the Certification of Polio Eradication certified the eradication of type 2 wild poliovirus, 1 of 3 wild poliovirus serotypes causing paralytic polio since the beginning of recorded history. This milestone was one of the key criteria prompting the Global Polio Eradication Initiative to begin withdrawal of oral polio vaccines (OPV), beginning with the type 2 component (OPV2), through a globally synchronized initiative in April and May 2016 that called for all OPV using countries and territories to simultaneously switch from use of trivalent OPV (tOPV; containing types 1, 2, and 3 poliovirus) to bivalent OPV (bOPV; containing types 1 and 3 poliovirus), thus withdrawing OPV2. Before the switch, immunization programs globally had been using approximately 2 billion tOPV doses per year to immunize hundreds of millions of children. Thus, the globally synchronized withdrawal of tOPV was an unprecedented achievement in immunization and was part of a crucial strategy for containment of polioviruses. Successful implementation of the switch called for intense global coordination during 2015-2016 on an unprecedented scale among global public health technical agencies and donors, vaccine manufacturers, regulatory agencies, World Health Organization (WHO) and United Nations Children's Fund (UNICEF) regional offices, and national governments. Priority activities included cessation of tOPV production and shipment, national inventories of tOPV, detailed forecasting of tOPV needs, bOPV licensing, scaling up of bOPV production and procurement, developing national operational switch plans, securing funding, establishing oversight and implementation committees and teams, training logisticians and health workers, fostering advocacy and communications, establishing monitoring and validation structures, and implementing waste management strategies. The WHO received confirmation that, by mid May 2016, all 155 countries and territories that had used OPV in 2015 had successfully withdrawn OPV2 by ceasing use of tOPV in their national immunization programs. This article provides an overview of the global efforts and challenges in successfully implementing this unprecedented global initiative, including (1) coordination and tracking of key global planning milestones, (2) guidance facilitating development of country specific plans, (3) challenges for planning and implementing the switch at the global level, and (4) best practices and lessons learned in meeting aggressive switch timelines. Lessons from this monumental public health achievement by countries and partners will likely be drawn upon when bOPV is withdrawn after polio eradication but also could be relevant for other global health initiatives with similarly complex mandates and accelerated timelines.

Dietary salt intake and time to relapse in paediatric multiple sclerosis.

BACKGROUND: Salt intake was reported to be associated with increased clinical and MRI activity in adult patients with relapsing-remitting multiple sclerosis (MS). OBJECTIVE: To determine if salt intake is associated with time to relapse in patients with paediatric-onset MS. METHODS: Paediatric-onset MS and patients with clinically isolated syndrome (CIS) within 4 years of disease onset were recruited from 15 paediatric MS centres in the USA as part of a case-control study. Patients with available prospective relapse data subsequent to enrolment were included in this project. Dietary sodium intake was assessed by self-report questionnaire using the validated Block Kids Food Screener. Cox proportional-hazards regression models were employed to determine the association of sodium density, excess sodium intake and sodium density tertiles with time to relapse following study enrolment, adjusting for several confounders. RESULTS: 174 relapsing-remitting MS/CIS patients were included in this analysis (mean age of 15.0 years, and 64.9% females). Median duration of follow-up was 1.8 years. In an unadjusted analysis, density of daily sodium intake was not associated with time to relapse, and patients with excess sodium intake had no decrease in time to relapse as compared with patients with non-excess sodium intake. The multivariable analysis demonstrated that patients in the medium and high tertile of sodium density had a HR of 0.69 (95% CI 0.37 to 1.30, p=0.25) and 1.37 (95% CI 0.74 to 2.51, p=0.32) compared with patients in the lowest tertile, respectively. CONCLUSIONS: Higher salt intake was not associated with decreased time to relapse in patients with paediatric-onset MS.

Cessation of Trivalent Oral Poliovirus Vaccine and Introduction of Inactivated Poliovirus Vaccine - Worldwide, 2016.

Since the 1988 World Health Assembly resolution to eradicate poliomyelitis, transmission of the three types of wild poliovirus (WPV) has been sharply reduced (1). WPV type 2 (WPV2) has not been detected since 1999 and was declared eradicated in September 2015. Because WPV type 3 has not been detected since November 2012, WPV type 1 (WPV1) is likely the only WPV that remains in circulation (1). This marked progress has been achieved through widespread use of oral poliovirus vaccines (OPVs), most commonly trivalent OPV (tOPV), which contains types 1, 2, and 3 live, attenuated polioviruses and has been a mainstay of efforts to prevent polio since the early 1960s. However, attenuated polioviruses in OPV can undergo genetic changes during replication, and in communities with low vaccination coverage, can result in vaccine-derived polioviruses (VDPVs) that can cause paralytic polio indistinguishable from the disease caused by WPVs (2). Among the 721 polio cases caused by circulating VDPVs (cVDPVs*) detected during January 2006-May 2016, type 2 cVDPVs (cVDPV2s) accounted for >94% (2). Eliminating the risk for polio caused by VDPVs will require stopping all OPV use. The first stage of OPV withdrawal involved a global, synchronized replacement of tOPV with bivalent OPV (bOPV) containing only types 1 and 3 attenuated polioviruses, planned for April 18-May 1, 2016, thereby withdrawing OPV type 2 from all immunization activities (3). Complementing the switch from tOPV to bOPV, introduction of at least 1 dose of injectable, trivalent inactivated poliovirus vaccine (IPV) into childhood immunization schedules reduces risks from and facilitates responses to cVDPV2 outbreaks. All 155 countries and territories that were still using OPV in immunization schedules in 2015 have reported that they had ceased use of tOPV by mid-May 2016.(†) As of August 31, 2016, 173 (89%) of 194 World Health Organization (WHO) countries included IPV in their immunization schedules.(§) The cessation of tOPV use is a major milestone toward the global goal of eradicating polio; however, careful surveillance for polioviruses and prompt, aggressive responses to polio outbreaks are still needed to realize a polio-free world.

"I Liked Girls and I Thought They Were Pretty": Initial Memories of Same-Sex Attraction in Young Lesbian and Bisexual Women.

There is little research on what is meant by the concept of "feeling attracted" and even less about what same-sex attraction looks and feels like for individuals. Without insight into the phenomenon of same-sex attraction, researchers risk misunderstanding the role of sexual attraction in sexual identity development and risk mis-categorizing individuals in research designs that compare LGBTQ and heterosexual samples. The current study draws from semi-structured interviews (n = 30) with young lesbian-, bisexual-, and queer-identified women (ages 18-24) about their initial memories of same-sex attraction. Two questions were pursued using qualitative analytic strategies. We examined the age that participants remembered first experiencing same-sex attraction using content analysis. Two age groups emerged as distinct: those with experiences of same-sex attraction in childhood and those with initial attractions in later adolescence. We also examined key elements in participants' descriptions of early same-sex attraction using thematic analysis. The role of embodied feelings, relationships with other young women, and social environments including media images emerged as central to initial experiences of attraction. Findings highlight how early experiences of same-sex attraction produced different types of interpretations within individuals and, in turn, these interpretations informed how participants did or did not take up LGBTQ identity labels. These findings may help guide the development of more refined measurement tools for researchers hoping to sample sexual minorities and can contribute to developing more effective supports for individuals who experience same-sex attraction but may not adopt LGBTQ identity labels and, as a result, are routinely missed in outreach efforts.

For debate: a new wave in public health improvement.

The rising burden of chronic disease poses a challenge for all public health systems and requires innovative approaches to effectively improve population health. Persisting inequalities in health are of particular concern. Disadvantage because of education, income, or social position is associated with a larger burden of disease and, in particular, multimorbidity. Although much has been achieved to enhance population health, challenges remain, and approaches need to be revisited. In this paper, we join the debate about how a new wave of public health improvement might look. We start from the premise that population health improvement is conditional on a health-promoting societal context. It is characterised by a culture in which healthy behaviours are the norm, and in which the institutional, social, and physical environment support this mindset. Achievement of this ambition will require a positive, holistic, eclectic, and collaborative effort, involving a broad range of stakeholders. We emphasise three mechanisms: maximisation of the value of health and incentives for healthy behaviour; promotion of healthy choices as default; and minimisation of factors that create a culture and environment which promote unhealthy behaviour. We give examples of how these mechanisms might be achieved.

Re-examining the effectiveness of monogamy as an STI-preventive strategy.

The utility of monogamy (in practice) as a strategy for preventing sexually transmitted infections (STIs) was investigated. By reviewing recent literature surrounding monogamous relationships and sexual behaviors, the authors determined that monogamy might not prevent against STIs as expected. First, the authors elucidate the ways in which public health officials and the general public define and interpret monogamy and discuss how this contributes to monogamy as an ineffectual STI prevention strategy. Second, the authors provide evidence that individuals' compliance with monogamy is likely to be low, similar to rates of compliance with other medical advice. Lastly, the authors draw upon recent research findings suggesting that people who label themselves as monogamous are less likely to engage in safer sex behaviors than people who have an explicit agreement with their partner to be non-monogamous. Future research and clinical directions to promote sexual health and destigmatize sexual behaviors are considered.

'Even though it's a small checkbox, it's a big deal': stresses and strains of managing sexual identity(s) on Facebook.

Facebook offers a socialisation context in which young people from ethnic, gender and sexual minorities must continually manage the potential for prejudice and discrimination in the form of homophobia and racism. In-depth interviews were conducted with eight young women, aged 16-19 years, who self-identified as queer and as women of colour. A detailed analysis of these interviews--focusing in particular on how young people described navigating expectations of rejection from family and friends--offered insight into the psychological and health consequences associated with managing sexual identity(s) while online. The 'closet' ultimately takes on new meaning in this virtual space: participants described trying to develop social relationships within Facebook, which demands sharing one's thoughts, behaviours and ideas, while also hiding and silencing their emerging sexuality. In this 'virtual closet', tempering self-presentation to offset social exclusion has become a continuous, yet personally treacherous, activity during the daily practice of using Facebook.

Diagnostic criteria for pediatric multiple sclerosis.

An estimated 2 % to 5 % of all persons with multiple sclerosis (MS) have onset of symptoms before 16 years of age Krupp and Hertz (Neurology 68(Suppl 2), 2007). As in adults, the diagnosis of pediatric MS is a clinical one, requiring recurrent episodes of CNS demyelination with supportive paraclinical data (MRI findings, CSF characteristics) in the absence of another plausible diagnosis. The differential diagnosis is broad and, the more atypical the case and the younger the child, the more consideration is necessary before making a diagnosis of MS. MS must be differentiated from acute disseminated encephalomyelitis (ADEM) or neuromyelitis optica (NMO). After initial presentation with a CNS demyelinating event or clinically isolated syndrome (CIS), children can meet the diagnostic criteria for MS if serial changes are noted on MRI and other disorders are excluded. Accurate diagnosis of pediatric MS is critical because of the implications of the diagnosis, including the need for long-term disease modifying therapy.

Retransitioning: The experiences of youth who socially transition genders more than once.

Background: Retransitions in youth are critical to understand, as they are an experience about which little is known and about which families and clinicians worry. Aims: This study aims to qualitatively describe the experiences of youth who made binary social transitions (came to live as the binary gender different from the one assigned at birth) in childhood by the age of 12, and who later socially transitioned genders again (here, called "retransitioning"). Methods: Out of 317 participants in an ongoing longitudinal study of (initially) binary transgender youth, 23 participants had retransitioned at least once and were therefore eligible for this study. Of those youth, 8 were cisgender at the time of data collection, 11 were nonbinary, and 4 were binary transgender youth (after having retransitioned to nonbinary identities for a period). Fifteen youth and/or their parent(s) participated in semi-structured interviews (MYouthA ge = 11.3 years; 9 non-Hispanic White; 3 Hispanic White; 3 Multiracial; 10 assigned male; 5 assigned female). Interviews gauged antecedents of transitions, others' reactions to transitions, and participants' general reflections. Responses were coded and thematically analyzed. Results: Participants described various paths to retransitions, including that some youth identified differently over time, and that some youth learned about a new identity (e.g., nonbinary) that fit them better. Social environments' responses to retransitions varied but were often neutral or positive. No participants spontaneously expressed regret over initial transitions. Conclusions: These findings largely do not support common concerns about retransitions. In supportive environments, gender diverse youth can retransition without experiencing rejection, distress, and regret.

Benefits of newborn screening and hematopoietic cell transplant in infantile Krabbe disease.

Infantile Krabbe disease (IKD) can be treated with hematopoietic cell transplantation (HCT) if done during the first weeks of life before symptoms develop. To facilitate this, newborn screening (NBS) has been instituted in 8 US states. An application to add IKD to the recommended NBS panel is currently under review. In this report, the outcomes of newborns with IKD diagnosed through NBS and treated with HCT are presented. The unique challenges associated with NBS for this disease are discussed, including opportunities for earlier diagnosis and streamlining treatment referrals. This is a retrospective review of six infants with IKD detected by NBS who were referred for HCT. The timing from diagnosis to HCT was examined, and both HCT and neurodevelopmental outcomes are described. Neurologic testing before HCT revealed evidence of active IKD in all infants. All underwent HCT between 24 and 40 days of age, were successfully engrafted, and are alive 30 to 58 months later (median, 47.5 months). All are gaining developmental milestones albeit at a slower pace than unaffected age-matched peers. Gross motor function is most notably affected. NBS for these patients enabled early access to HCT, the only currently available treatment of infants with IKD. All children are alive and have derived developmental and neurologic benefits from timely HCT. Long-term follow up is ongoing. Optimization of HCT and further development of emerging therapies, all of which must be delivered early in life, are expected to further improve outcomes of infants with IKD.