Maximal dietary responsiveness after tetrahydrobiopterin (BH4) in 19 phenylalanine hydroxylase deficiency patients: What super-responders can expect

Background

Inherited phenylalanine hydroxylase deficiency, also known as phenylketonuria (PKU), causes poor growth and neurologic deficits in the untreated state. After ascertainment through newborn screen and dietary phenylalanine (Phe) restriction to achieve plasma Phe in the range of 120-360 μmol/L, these disease manifestations can be prevented. Poor compliance with protein restricted diets supported by medical food is typical in later years, beginning in the late toddler and teenage years. Pharmacologic doses of oral tetrahydrobiopterin (BH4; sapropterin dihydrochloride) is effective in reducing plasma Phe in about 40-50% of PKU patients but effectiveness is highly variable.

Objective

To assess the maximal responsiveness to 20 mg/kg/day oral BH4 as it affects plasma Phe and dietary Phe allowance in PKU patients.

Materials and methods

This was a single-center, retrospective observational study, combining case reports of individual patients. We reported an outcome of 85 patients with PKU who were trialed on BH4. Phe levels and dietary records of 19 BH4 "super-responders" were analyzed.

Results

Overall, 63.5% of the patients (54/85) were considered BH4 responders. However, we quantitated the dietary liberalization of 19 of our responsive patients (35%), those with at least a 2-fold increase in dietary Phe and maintenance of plasma Phe in treatment range. In these "super-responders", the mean plasma Phe at baseline was 371 ± 237 μmol/L and decreased to 284 ± 273 μmol/L after 1 year on BH4. Mean dietary Phe tolerance increased significantly from 595 ± 256 to 2260 ± 1414 mg/day (p ≤0.0001), while maintaining mean plasma Phe levels within treatment range. Four patients no longer required dietary Phe restriction and could discontinue medical food. The majority of patients had at least one BH4-responsive genotype.

Conclusion

This cohort demonstrates the maximally achievable dietary liberalization which some PKU patients may expect with BH4 therapy. Health benefits are considered to accrue in patients with increased intact protein.

Biochemical and molecular characteristics among infants with abnormal newborn screen for very-long-chain acyl-CoA dehydrogenase deficiency: A single center experience

Objective

To define the biochemical and molecular characteristics and diagnostic outcomes of a large US cohort of VLCAD deficiency positive cases as detected by newborn screening (NBS) with MS:MS. This relatively common disorder of fatty acid oxidation is screened for in every state in America and often results in extensive testing of multiple samples to arrive at a diagnostic conclusion.

Materials and methods

We compared NBS dried blood spot (DBS) acylcarnitine profile (ACP) C14, C14:1, C14:2, C14:1/C12:1 ratio and plasma C14, C14:1, C14:2, C14:1/C12:1, C14:1/C16 and C14:1/C2 ratios among true positive and false positive cases. Results of VLCAD enzyme analysis, molecular testing and fibroblast fatty acid oxidation probe assay were analyzed.

Results

The presence of compound heterozygous or homozygous pathogenic variants, along with elevations of C14, C14:1 and C14:1/C12:1 ratio, identified 19 VLCAD deficiency cases. All were asymptomatic at most recent follow-up visits. The C14:1/C12:1 ratio in NBS-DBS ACP and plasma acylcarnitine profiles at follow-up (follow-up plasma ACP), is the most useful marker to differentiate between true and false positive cases. Among all cases with molecular analysis data available, approximately 56.7% had a single pathogenic mutation. Lymphocyte enzyme analysis (n = 61) was uninformative in 23% of cases studied.

Conclusion

VLCAD deficiency NBS by MS:MS is highly effective at identifying asymptomatic affected infants. Our cohort showed that elevation of C14:1/C12:1, in both NBS DBS and plasma ACP, was informative in discriminating affected from unaffected individuals and contributes to improve the accuracy of confirmatory testing of infants with presumptive positive for VLCAD deficiency.

Variants in GNAI1 cause a syndrome associated with variable features including developmental delay, seizures, and hypotonia

PURPOSE

Neurodevelopmental disorders (NDDs) encompass a spectrum of genetically heterogeneous disorders with features that commonly include developmental delay, intellectual disability, and autism spectrum disorders. We sought to delineate the molecular and phenotypic spectrum of a novel neurodevelopmental disorder caused by variants in the GNAI1 gene.

METHODS

Through large cohort trio-based exome sequencing and international data-sharing, we identified 24 unrelated individuals with NDD phenotypes and a variant in GNAI1, which encodes the inhibitory Gαi1 subunit of heterotrimeric G-proteins. We collected detailed genotype and phenotype information for each affected individual.

RESULTS

We identified 16 unique variants in GNAI1 in 24 affected individuals; 23 occurred de novo and 1 was inherited from a mosaic parent. Most affected individuals have a severe neurodevelopmental disorder. Core features include global developmental delay, intellectual disability, hypotonia, and epilepsy.

CONCLUSION

This collaboration establishes GNAI1 variants as a cause of NDDs. GNAI1-related NDD is most often characterized by severe to profound delays, hypotonia, epilepsy that ranges from self-limiting to intractable, behavior problems, and variable mild dysmorphic features.

Medical Decision Support to Reduce Unwarranted Methylene Tetrahydrofolate Reductase (MTHFR) Genetic Testing

Most major national medical associations have advised against routine MTHFR testing since at least 2013. However, many providers continue to order this unwarranted genetic test. This study assessed the efficacy of an electronic best practice alert to aid ordering providers. We tracked the rate of MTHFR tests ordered per 1 million patients in the twelve months before and after the implementation of an alert that suggested an alternative test. Associated factors including the ordering department, diagnosis, patient sex, and patient age were also analyzed. Chi square analysis was used to compare the difference between pre- and post-alert test ordering rates. A total of 997 MTHFR analysis were ordered in Southern California Kaiser Permanente from January 2017 through December 2018. Overall, the average MTHFR monthly test ordering rates dropped significantly from 12.93 per million patients in 2017 to 7.08 per million patients in 2018 (p = 0.0056). However, testing rates in children were unchanged and, in some associated diagnoses, such as psychiatric illnesses and neurodevelopmental conditions, the testing rates increased. Recommending an alternate test in lieu of the unwarranted one significantly reduced the overall rate of MTHFR testing. The alert was most effective for specialties and diagnoses where MTHFR was historically medically indicated. This suggests such alerts are an effective intervention that health care systems can implement to serve as an educational update and to reduce unwarranted genetic testing.

Dual specific oral tolerance induction using interferon gamma for IgE-mediated anaphylactic food allergy and the dissociation of local skin allergy and systemic oral allergy: tolerance or desensitization?

BACKGROUND

Specific oral tolerance induction (SOTI) for IgE-mediated food allergy (IFA) can be successfully achieved using interfero gamma (classic SOTI).

OBJECTIVE

In this study, a tolerable dose was introduced during tolerance induction with interferon gamma (dual SOTI), and its effectiveness was evaluated.

METHODS

The study population comprised 25 IFA patients. Blood samples were taken for analysis, including complete blood count with differential counts of eosinophils, serum total IgE levels, and specific IgE for allergenic foods. Skin prick tests were conducted with the allergens. Oral food challenges were performed to diagnose IFA. Ten patients received dual SOTI, 5 received classic SOTI, 5 received SOTI without interferon gamma (original SOTI), and 5 were not treated (controls).

RESULTS

Patients treated with dual SOTI and classic SOTI using interferon gamma became tolerant to the allergenic food. The tolerable dose was introduced successfully in dual SOTI. It was difficult to proceed with the same dosing protocol used for classic SOTI in cases treated with original SOTI. Following dual SOTI, the systemic reaction to oral intake subsided, but the local skin reaction to contact with the allergenic food persisted.

CONCLUSIONS

Dual SOTI is an improved protocol for SOTI using interferon gamma for IFA.The local skin reaction and systemic reaction to oral intake were dissociated following dual SOTI. In cases of food allergy, tolerance appears to result from desensitization to allergens.

Angiotensin II-accelerated atherosclerosis and aneurysm formation is attenuated in osteopontin-deficient mice

Osteopontin (OPN) is expressed in atherosclerotic lesions, particularly in diabetic patients. To determine the role of OPN in atherogenesis, ApoE-/-OPN+/+, ApoE-/-OPN+/-, and ApoE-/-OPN-/- mice were infused with Ang II, inducing vascular OPN expression and accelerating atherosclerosis. Compared with ApoE-/-OPN+/+ mice, ApoE-/-OPN+/- and ApoE-/-OPN-/- mice developed less Ang II-accelerated atherosclerosis. ApoE-/- mice transplanted with bone marrow derived from ApoE-/-OPN-/- mice had less Ang II-induced atherosclerosis compared with animals receiving ApoE-/-OPN+/+ cells. Aortae from Ang II-infused ApoE-/-OPN-/- mice expressed less CD68, C-C-chemokine receptor 2, and VCAM-1. In response to intraperitoneal thioglycollate, recruitment of leukocytes in OPN-/- mice was impaired, and OPN-/- leukocytes exhibited decreased basal and MCP-1-directed migration. Furthermore, macrophage viability in atherosclerotic lesions from Ang II-infused ApoE-/-OPN-/- mice was decreased. Finally, Ang II-induced abdominal aortic aneurysm formation in ApoE-/-OPN-/- mice was reduced and associated with decreased MMP-2 and MMP-9 activity. These data suggest an important role for leukocyte-derived OPN in mediating Ang II-accelerated atherosclerosis and aneurysm formation.

Synthetic LXR ligand inhibits the development of atherosclerosis in mice

The nuclear receptors LXRalpha and LXRbeta have been implicated in the control of cholesterol and fatty acid metabolism in multiple cell types. Activation of these receptors stimulates cholesterol efflux in macrophages, promotes bile acid synthesis in liver, and inhibits intestinal cholesterol absorption, actions that would collectively be expected to reduce atherosclerotic risk. However, synthetic LXR ligands have also been shown to induce lipogenesis and hypertriglyceridemia in mice, raising questions as to the net effects of these compounds on the development of cardiovascular disease. We demonstrate here that the nonsteroidal LXR agonist GW3965 has potent antiatherogenic activity in two different murine models. In LDLR(-/-) mice, GW3965 reduced lesion area by 53% in males and 34% in females. A similar reduction of 47% was observed in male apoE(-/-) mice. Long-term (12-week) treatment with LXR agonist had differential effects on plasma lipid profiles in LDLR(-/-) and apoE(-/-) mice. GW3965 induced expression of ATP-binding cassettes A1 and G1 in modified low-density lipoprotein-loaded macrophages in vitro as well as in the aortas of hyperlipidemic mice, suggesting that direct actions of LXR ligands on vascular gene expression are likely to contribute to their antiatherogenic effects. These observations provide direct evidence for an atheroprotective effect of LXR agonists and support their further evaluation as potential modulators of human cardiovascular disease.

Intravenous immune globulin effects on serum-soluble CD5 levels in atopic dermatitis

BACKGROUND

Intravenous immune globulin (IVIG) therapy has been tried in the treatment of atopic dermatitis. Recently, the presence of serum-soluble CD5 (ssCD5) in atopic dermatitis was reported.

OBJECTIVE

IVIG effects on ssCD5 levels in atopic dermatitis were examined and the correlation of ssCD5 level changes with clinical and laboratory parameters were investigated.

METHODS

IVIG therapy was tried on 40 atopic dermatitis and 17 recurrent spontaneous abortion patients. Five atopic dermatitis patients received normal saline as a placebo control group. The clinical and laboratory parameters were evaluated on day 0, 1, 7 and 21 after administering the IVIG therapy.

RESULTS

With IVIG therapy, in atopic dermatitis, the ssCD5 level was 5.5 +/- 6.2 ng/mL before infusion (day 0), 15.2 +/- 12.1 ng/mL on day 1, 13.8 +/- 14.1 ng/mL on day 7, and 3.9 +/- 4.1 ng/mL on day 21. The clinical severity score was 350.5 +/- 120.3 on day 0, 420.4 +/- 174.8 on day 1, 250.0 +/- 121.2 on day 7, and 115.5 +/- 53.9 on day 21. White blood cell (WBC) counts and serum IgE levels showed a gradual decrease with IVIG infusions. Blood eosinophil fractions were 5.3 +/- 2.8% on day 0, 8.6 +/- 5.2% on day 1, 7.3 +/- 3.7% on day 7, and 6.8 +/- 4.0% on day 21. Changes in the total eosinophil count were insignificantly parallel with those of blood eosinophil fractions

CONCLUSION

In atopic dermatitis, IVIG therapy increased the ssCD5 levels. Further studies concerning the exact role of ssCD5 are needed.

The necessity of diet therapy for successful interferon-gamma therapy in atopic dermatitis

The avoidance of incriminated foods is one of the principal therapies for atopic dermatitis (AD). Recently, interferon (IFN)-gamma therapy has been tried in AD with limited success. The necessity of diet therapy for the success of IFN-gamma therapy in AD was evaluated. A total of 524 AD patients participated in this study and 316 patients among them were entered into open food challenge tests. As the first step, an elimination diet was administered to 43 AD patients and 30 AD patients were enrolled as an untreated control group. As the second step, 45 AD patients were treated by both IFN-gamma therapy and elimination diet alone, 30 AD patients by elimination diet alone, 50 AD patients by IFN-gamma therapy, and 43 AD patients as controls. Clinical severity reduced significantly by using only the elimination diet in 58.1% patients with varying degrees of AD. Elimination diet improved the clinical results of IFN-gamma therapy in AD. In regard to the food challenge test, 77.8% of AD patients showed an adverse reaction to at least one food. Diet therapy itself had therapeutic effects on AD and an elimination diet might be essential for the success of IFN-gamma therapy in AD.

Troglitazone inhibits formation of early atherosclerotic lesions in diabetic and nondiabetic low density lipoprotein receptor-deficient mice

Peroxisome proliferator-activated receptor-gamma (PPARgamma) is a ligand-activated nuclear receptor expressed in all of the major cell types found in atherosclerotic lesions: monocytes/macrophages, endothelial cells, and smooth muscle cells. In vitro, PPARgamma ligands inhibit cell proliferation and migration, 2 processes critical for vascular lesion formation. In contrast to these putative antiatherogenic activities, PPARgamma has been shown in vitro to upregulate the CD36 scavenger receptor, which could promote foam cell formation. Thus, it is unclear what impact PPARgamma activation will have on the development and progression of atherosclerosis. This issue is important because thiazolidinediones, which are ligands for PPARgamma, have recently been approved for the treatment of type 2 diabetes, a state of accelerated atherosclerosis. We report herein that the PPARgamma ligand, troglitazone, inhibited lesion formation in male low density lipoprotein receptor-deficient mice fed either a high-fat diet, which also induces type 2 diabetes, or a high-fructose diet. Troglitazone decreased the accumulation of macrophages in intimal xanthomas, consistent with our in vitro observation that troglitazone and another thiazolidinedione, rosiglitazone, inhibited monocyte chemoattractant protein-1-directed transendothelial migration of monocytes. Although troglitazone had some beneficial effects on metabolic risk factors (in particular, a reduction of insulin levels in the diabetic model), none of the systemic cardiovascular risk factors was consistently improved in either model. These observations suggest that the inhibition of early atherosclerotic lesion formation by troglitazone may result, at least in part, from direct effects of PPARgamma activation in the artery wall.

Successful interferon alpha therapy in atopic dermatitis of Besnier's prurigo pattern with normal serum IgE and blood eosinophil fraction: randomized case-controlled study

A randomized case-controlled study was carried out to investigate for interferon alpha therapy in atopic dermatitis (AD) of Besnier's prurigo pattern with normal serum IgE and normal blood eosinophil fraction. Interferon alpha therapy was conducted on 14 non-responders to interferon gamma and subsequent thymopentin therapy among 100 atopic dermatitis patients. Eight patients who improved significantly, showed skin lesions of the Besnier's prurigo pattern with normal serum IgE and normal blood eosinophil fraction. For the randomized prospective case-controlled study, 44 patients with the above characteristics were selected. Thirteen Besnier's prurigo patients were treated with interferon alpha therapy, ten with interferon gamma, ten with thymopentin, and the remaining 11 were untreated as the control group. With interferon alpha therapy, 11 out of 13 Besnier's prurigo patients with normal IgE and normal blood eosinophil fraction improved significantly, two out of ten improved with interferon gamma therapy, and none improved with thymopentin therapy or in the untreated control group. Interferon alpha therapy was effective on AD of Besnier's prurigo pattern with normal serum IgE and normal blood eosinophil fraction. These results suggest the possibility of non-IgE-mediated AD and the heterogeneity of atopic dermatitis.

Pilot study of IFN-gamma-induced specific hyposensitization for house dust mites in atopic dermatitis: IFN-gamma-induced immune deviation as a new therapeutic concept for atopic dermatitis

IFN-gamma/IL-4 imbalance is a central immunologic defect which is responsible for increased IgE antibody response in atopic dermatitis. Effects of hyposensitization were controversial in atopic dermatitis. Reversed IFN-gamma/IL-4 balance was induced using IFN-gamma in atopic dermatitis and specific hyposensitization with house dust mites (HDM) was tried in the status of IFN-gamma-induced immune deviation. A total of 58 atopic dermatitis patients who had obvious allergy to HDM were selected in this study. IFN-gamma-induced hyposensitization for HDM was tried in 10 patients. Twenty-two patients received IFN-gamma therapy and six were treated by simple hyposensitization. Twenty were enrolled as control subjects. The clinical severity scores decreased effectively only by IFN-gamma-induced hyposensitization for HDM. Specific hyposensitization for HDM in the status of IFN-gamma-induced immune deviation successfully improved atopic dermatitis. HDM might play a pathogenic role in subpopulation of atopic dermatitis.

Intravenous immune globulin (i.v.IG) therapy in steroid-resistant atopic dermatitis

Many trials have been done on steroid-resistant atopic dermatitis. Recently, intravenous immune globulin (i.v.IG) was reported to be effective in the treatment of steroid-dependent atopic dermatitis. The aim of this study was to clarify whether i.v.IG therapy is effective in steroid-resistant atopic dermatitis. Forty-one steroid-resistant atopic dermatitis patients were tested in this study. Patients who weighed less than 30 kg were administered 500 mg/kg of i.v.IG. Patients who weighed 30 kg or more were administered 15 g of i.v.IG. Patient evaluations and laboratory tests with peripheral bloods such as eosinophil percentages and serum IgE levels were performed at days 0, 1, 7, and 21. In the present study, patients who responded to i.v.IG therapy were classified as Group A. Twelve patients who showed transient effects with lower clinical significance were classified as Group B (29.3%). Remaining 12 patients (29.3%) in Group C showed no improvement at all. Serum IgE levels and blood eosinophil percentages were markedly decreased in Group A. I.v.IG therapy may be recommended in the treatment of atopic dermatitis with extremely high serum IgE levels.

Computing system for pediatric cardiology (CathEcho 2.5)

CathEcho version 2.5 (CathEcho 2.0) was developed as database system of clinical data for pediatric cardiology patients including X-ray and echocardiogram picture for a scientific purpose. We classified congenital heart defects and combined these data to meet any diagnosis or syndrome and any diagnostic coding system. Anatomical data was saved systematically along the anatomical hierarchy of heart. Laboratory data were calculated automatically after the validation. All congenital defects were revised and diagnosis was made automatically. In this system the determination of operation can be suggested according to the cardiac indexes and data can be reported as clinical charts. We can monitor the statistics of patient data and obtain information about patient clinical data easily even at emergency state. This system can make physician to have complete examination about congenital heart disease as well as other heart state. The followings are the main constitutions of the CathEcho version 2.5. BASIC INFORMATION RECORDS. In this part, the unique number is given to any patient. The basic patient informations are checked and stored as clinical data for the management of patients and for the research purposes. CARDIAC CATHETERIZATION RECORDS. Cardiac catheterization data are recorded in this part. The cardiac anatomical data are recorded in according to the segmental steps and the anatomical relationships. Laboratory data are recorded and the cardiac indexes are calculated automatically. This system can recommend the therapeutic plans on operation. Final diagnosis can be automatically arranged by a complete revision of anatomical and laboratory data. CARDIAC ECHOCARDIOGRAM RECORDS. Echocardiogram data are recorded systematically and the cardiac indexes can be calculated automatically. This system also can recommend the necessity of the operation. Full anatomical and laboratory data are completely revised and diagnosis can be made automatically. ELECTROCARDIOGRAPHY (EKG) RECORDS. EKG data are stored systematically and reported with catheterization data, echo data and X-ray data. X-RAY RECORDS. X-ray data of patients also are stored for the complete clinical data. With CathEcho 2.5 we are now storing the formatted clinical data for the expert systems which are now being developed to assist the therapeutic planning and updated to link to cardiac electrophysiology.