"Exogenous" 5 Alpha Reductase Deficiency: A Case Report

Testosterone and dihydrotestosterone are significant drivers of male external genital development, and therefore teratogens that alter these hormone profiles have been hypothesized to cause aberrations in development. Here, we present the first case report of genitalia anomalies after prenatal exposure to spironolactone and dutasteride through 8-weeks of gestation. The patient was born with abnormal male external genitalia which was surgically managed. Long-term outcomes such as gender identity, sexual function, hormonal maturation through puberty, and fertility remain unknown. These numerous considerations necessitate multi-disciplinary management with close follow-up to address sexual, psychological, and anatomic concerns.

Diagnosis and management of glycogen storage diseases type VI and IX: a clinical practice resource of the American College of Medical Genetics and Genomics (ACMG)

PURPOSE

Glycogen storage disease (GSD) types VI and IX are rare diseases of variable clinical severity affecting primarily the liver. GSD VI is caused by deficient activity of hepatic glycogen phosphorylase, an enzyme encoded by the PYGL gene. GSD IX is caused by deficient activity of phosphorylase kinase (PhK), the enzyme subunits of which are encoded by various genes: ɑ (PHKA1, PHKA2), β (PHKB), ɣ (PHKG1, PHKG2), and δ (CALM1, CALM2, CALM3). Glycogen storage disease types VI and IX have a wide spectrum of clinical manifestations and often cannot be distinguished from each other, or from other liver GSDs, on clinical presentation alone. Individuals with GSDs VI and IX can present with hepatomegaly with elevated serum transaminases, ketotic hypoglycemia, hyperlipidemia, and poor growth. This guideline for the management of GSDs VI and IX was developed as an educational resource for health-care providers to facilitate prompt and accurate diagnosis and appropriate management of patients.

METHODS

A national group of experts in various aspects of GSDs VI and IX met to review the limited evidence base from the scientific literature and provided their expert opinions. Consensus was developed in each area of diagnosis, treatment, and management. Evidence bases for these rare disorders are largely based on expert opinion, particularly when targeted therapeutics that have to clear the US Food and Drug Administration (FDA) remain unavailable.

RESULTS

This management guideline specifically addresses evaluation and diagnosis across multiple organ systems involved in GSDs VI and IX. Conditions to consider in a differential diagnosis stemming from presenting features and diagnostic algorithms are discussed. Aspects of diagnostic evaluation and nutritional and medical management, including care coordination, genetic counseling, and prenatal diagnosis are addressed.

CONCLUSION

A guideline that will facilitate the accurate diagnosis and optimal management of patients with GSDs VI and IX was developed. This guideline will help health-care providers recognize patients with GSDs VI and IX, expedite diagnosis, and minimize adverse sequelae from delayed diagnosis and inappropriate management. It will also help identify gaps in scientific knowledge that exist today and suggest future studies.

Inheritance of HLA-Cw7 Associated With Autism Spectrum Disorder (ASD)

Autism spectrum disorder (ASD) is a behaviorally defined disorder that is now thought to affect approximately 1 in 69 children in the United States. In most cases, the etiology is unknown, but several studies point to the interaction of genetic predisposition with environmental factors. The immune system is thought to have a causative role in ASD, and specific studies have implicated T lymphocytes, monocytes, natural killer (NK) cells, and certain cytokines. The human leukocyte antigen (HLA) system is involved in the underlying process for shaping an individual's immune system, and specific HLA alleles are associated with specific diseases as risk factors. In this study, we determine whether a specific HLA allele was associated with ASD in a large cohort of patients with ASD. Identifying such an association could help in the identification of immune system components which may have a causative role in specific cohorts of patients with ASD who share similar specific clinical features. Specimens from 143 patients with ASD were analyzed with respect to race and ethnicity. Overall, HLA-Cw7 was present in a much greater frequency than expected in individuals with ASD as compared to the general population. Further, the cohort of patients who express HLA-Cw7 shares specific immune system/inflammatory clinical features including being more likely to have allergies, food intolerances, and chronic sinusitis as compared to those with ASD who did not express HLA-Cw7. HLA-Cw7 has a role in stimulating NK cells. Thus, this finding may indicate that chronic over-activation of NK cells may have a role in the manifestation of ASD in a cohort of patients with increased immune system/inflammatory features.

Bioenergetic variation is related to autism symptomatology

Autism spectrum disorder (ASD) has been associated with mitochondrial dysfunction but few studies have examined the relationship between mitochondrial function and ASD symptoms. We measured Complex I and IV and citrate synthase activities in 76 children with ASD who were not receiving vitamin supplementation or medication. We also measured language using the Preschool Language Scales or Clinical Evaluation of Language Fundamentals, adaptive behavior using the Vineland Adaptive Behavioral Scale, social function using the Social Responsiveness Scale and behavior using Aberrant Behavior Checklist, Childhood Behavior Checklist and the Ohio Autism Clinical Impression Scale. Children with ASD demonstrated significantly greater variation in mitochondrial activity compared to controls with more than expected ASD children having enzyme activity outside of the normal range for Citrate Synthase (24%), Complex I (39%) and Complex IV (11%). Poorer adaptive skills were associated with Complex IV activity lower or higher than average and lower Complex I activity. Poorer social function and behavior was associated with relatively higher Citrate Synthase activity. Similar to previous studies we find both mitochondrial underactivity and overactivity in ASD. This study confirms an expanded variation in mitochondrial activity in ASD and demonstrates, for the first time, that such variations are related to ASD symptoms.

Mitochondrial Dysfunction may explain symptom variation in Phelan-McDermid Syndrome

Phelan-McDermid Syndrome (PMS), which is defined by a deletion within 22q13, demonstrates significant phenotypic variation. Given that six mitochondrial genes are located within 22q13, including complex I and IV genes, we hypothesize that mitochondrial complex activity abnormalities may explain phenotypic variation in PMS symptoms. Complex I, II, II + III and IV activity was measured in 51 PMS participants. Caretakers completed questionnaires and provided genetic information through the PMS foundation registry. Complex activity was abnormal in 59% of PMS participants. Abnormalities were found in complex I and IV but not complex II + III and II activity, consistent with disruption of genes within the 22q13 region. However, complex activity abnormalities were not related to specific gene deletions suggesting a "neighboring effect" of regional deletions on adjacent gene expression. A specific combination of symptoms (autism spectrum disorder, developmental regression, failure-to-thrive, exercise intolerance/fatigue) was associated with complex activity abnormalities. 64% of 106 individuals in the PMS foundation registry who did not have complex activity measured also endorsed this pattern of symptoms. These data suggest that mitochondrial abnormalities, specifically abnormalities in complex I and IV activity, may explain some phenotypic variation in PMS individuals. These results point to novel pathophysiology mechanisms and treatment targets for PMS patients.

Expanding the clinical and molecular characteristics of PIGT-CDG, a disorder of glycosylphosphatidylinositol anchors

PIGT-CDG, an autosomal recessive syndromic intellectual disability disorder of glycosylphosphatidylinositol (GPI) anchors, was recently described in two independent kindreds [Multiple Congenital Anomalies-Hypotonia-Seizures Syndrome 3 (OMIM, #615398)]. PIGT encodes phosphatidylinositol-glycan biosynthesis class T, a subunit of the heteropentameric transamidase complex that facilitates the transfer of GPI to proteins. GPI facilitates attachment (anchoring) of proteins to cell membranes. We describe, at ages 7 and 6 years, two children of non-consanguineous parents; they had hypotonia, severe global developmental delay, and intractable seizures along with endocrine, ophthalmologic, skeletal, hearing, and cardiac anomalies. Exome sequencing revealed that both siblings had compound heterozygous variants in PIGT (NM_015937.5), i.e., c.918dupC, a novel duplication leading to a frameshift, and c.1342C > T encoding a previously described missense variant. Flow cytometry studies showed decreased surface expression of GPI-anchored proteins on granulocytes, consistent with findings in previous cases. These siblings further delineate the clinical spectrum of PIGT-CDG, reemphasize the neuro-ophthalmologic presentation, clarify the endocrine features, and add hypermobility, low CSF albumin quotient, and hearing loss to the phenotypic spectrum. Our results emphasize that GPI anchor-related congenital disorders of glycosylation (CDGs) should be considered in subjects with early onset severe seizure disorders and dysmorphic facial features, even in the presence of a normal carbohydrate-deficient transferrin pattern and N-glycan profiling. Currently available screening for CDGs will not reliably detect this family of disorders, and our case reaffirms that the use of flow cytometry and genetic testing is essential for diagnosis in this group of disorders.

Approaches to studying and manipulating the enteric microbiome to improve autism symptoms

There is a growing body of scientific evidence that the health of the microbiome (the trillions of microbes that inhabit the human host) plays an important role in maintaining the health of the host and that disruptions in the microbiome may play a role in certain disease processes. An increasing number of research studies have provided evidence that the composition of the gut (enteric) microbiome (GM) in at least a subset of individuals with autism spectrum disorder (ASD) deviates from what is usually observed in typically developing individuals. There are several lines of research that suggest that specific changes in the GM could be causative or highly associated with driving core and associated ASD symptoms, pathology, and comorbidities which include gastrointestinal symptoms, although it is also a possibility that these changes, in whole or in part, could be a consequence of underlying pathophysiological features associated with ASD. However, if the GM truly plays a causative role in ASD, then the manipulation of the GM could potentially be leveraged as a therapeutic approach to improve ASD symptoms and/or comorbidities, including gastrointestinal symptoms. One approach to investigating this possibility in greater detail includes a highly controlled clinical trial in which the GM is systematically manipulated to determine its significance in individuals with ASD. To outline the important issues that would be required to design such a study, a group of clinicians, research scientists, and parents of children with ASD participated in an interdisciplinary daylong workshop as an extension of the 1st International Symposium on the Microbiome in Health and Disease with a Special Focus on Autism (www.microbiome-autism.com). The group considered several aspects of designing clinical studies, including clinical trial design, treatments that could potentially be used in a clinical trial, appropriate ASD participants for the clinical trial, behavioral and cognitive assessments, important biomarkers, safety concerns, and ethical considerations. Overall, the group not only felt that this was a promising area of research for the ASD population and a promising avenue for potential treatment but also felt that further basic and translational research was needed to clarify the clinical utility of such treatments and to elucidate possible mechanisms responsible for a clinical response, so that new treatments and approaches may be discovered and/or fostered in the future.

A Delphi-based consensus clinical practice protocol for the diagnosis and management of 3-methylcrotonyl CoA carboxylase deficiency

3-MCC deficiency is among the most common inborn errors of metabolism identified on expanded newborn screening (1:36,000 births). However, evidence-based guidelines for diagnosis and management of this disorder are lacking. Using the traditional Delphi method, a panel of 15 experts in inborn errors of metabolism was convened to develop consensus-based clinical practice guidelines for the diagnosis and management of 3-MCC screen-positive infants and their mothers. The Oxford Centre for Evidence-based Medicine system was used to grade the literature review and create recommendations graded from A (evidence level of randomized clinical trials) to D (expert opinion). Panelists reviewed the initial evaluation of the screen-positive infant-mother dyad, diagnostic guidelines, and management of diagnosed patients. Grade D consensus recommendations were made in each of these three areas. The panel did not reach consensus on all issues. This consensus protocol is intended to assist clinicians in the diagnosis and management of screen-positive newborns for 3-MCC deficiency and to encourage the development of evidence-based guidelines.

45,X/47,XYY mosaicism: clinical discrepancy between prenatally and postnatally diagnosed cases

45,X/47,XYY mosaicism is a rare chromosomal disorder with clinical information limited to 11 postnatal cases in the literature and with uncertainty regarding prenatal prediction of phenotype and prognosis. We report on 7 new cases of 45,X/47,XYY mosaicism, three detected prenatally and 4 diagnosed postnatally. A clinical comparison of the cases of 45,X/47,XYY mosaicism is presented together with a literature review.