Natural history of cardiac findings in mucopolysaccharidosis type I: report from an international registry

Mucopolysaccharidosis type I is an inborn error of glycosaminoglycan catabolism with phenotypes ranging from severe (Hurler syndrome) to attenuated (Hurler-Scheie and Scheie syndromes). Cardiovascular involvement is common and contributes significantly to morbidity and mortality. We conducted a retrospective analysis of the prevalence and natural history of cardiac abnormalities in treatment-naïve individuals enrolled in the international Mucopolysaccharidosis Type I Registry. Interrogation of echocardiography data (presence of cardiac valve regurgitation and/or stenosis; measurements of left ventricular chamber dimensions in diastole and systole, diastolic left ventricular posterior wall and interventricular septal thicknesses and ventricular systolic function (shortening fraction)) showed that mitral regurgitation was the most common and earliest finding for individuals with both severe (58.3%, median age 1.2 years) and attenuated (74.2%, median age 8.0 years) disease. Left-sided valve stenosis was also common in individuals with attenuated disease (mitral 30.3%; aortic 25%). Abnormal ventricular wall and septal thickness (Z-scores ≥2) were observed early in both phenotypes. Z-scores for diastolic left ventricular posterior wall and interventricular septal thicknesses increased with age in the severe phenotype (annualised slopes of 0.2777 [p = 0.037] and 0.3831 [p = 0.001], respectively); a similar correlation was not observed in the attenuated phenotype (annualised slopes of -0.0401 [p = 0.069] and -0.0029 [p = 0.875], respectively). Decreased cardiac ventricular systolic function (defined as shortening fraction <28%) was uncommon but, when noted, was more frequent in infants with the severe phenotype. While cardiac abnormalities occur early in both severe and attenuated mucopolysaccharidosis type I, the pattern of valve dysfunction and progression of ventricular abnormalities vary by phenotype.

Long term disease burden post-transplantation: three decades of observations in 25 Hurler patients successfully treated with hematopoietic stem cell transplantation (HSCT)

BACKGROUND

Mucopolysaccharidosis type I-Hurler syndrome (MPSI-H) is a lysosomal storage disease characterized by severe physical symptoms and cognitive decline. Early treatment with hematopoietic cell transplant (HSCT) is critical to the survival of these patients. While survival rates and short-term outcomes are known to be improved by HSCT, the long-term cognitive, adaptive and psychosocial functional outcomes of children with (MPSI-H) post-HSCT are not well documented. This manuscript focuses on retrospective long-term follow-up (7-33 years) of 25 MPSI-H patients, transplanted between 1986 and 2011.

RESULTS

The median age at transplantation was 21 months (range 12-57 months). Except for one death, all successfully transplanted MPSI-H patients surviving at least 1 year after HSCT are alive to-date, with a median age of 21 years (range 8-36 years) at the last follow-up evaluation. A majority of HSCT grafts were bone marrow transplants (BMT), resulting in durable full chimerism in 18 (72%). Pre-HSCT, the onset of first symptoms occurred very early, at a median age of 3 months (range birth-16 months). The most prevalent symptoms before MPSI-H diagnosis involved progressive dysostosis multiplex; almost all patients suffered from hip dysplasia and thoracolumbar spine Kyphosis. Despite HSCT, considerable residual disease burden and ensuing corrective surgical interventions were observed in all, and at every decade of follow-up post HSCT. Late-onset psychiatric manifestations were significant (n = 17 patients; 68%), including depression in 13 patients at a median onset age of 18 years (range 13-31 years), hyperactivity and attention deficit disorder (n = 4), and multiple acute psychotic episodes (APE), independent of depression observed (n = 3) at a median onset age of 18 years (range 17-31 years). The adult Welscher Intelligence Scale results (n = 16) were heterogenous across the four scale dimensions; overall lower scores were observed on both working memory index (median WMI = 69.5) and processing speed index (median PSI = 65), whereas verbal comprehension index (median VCI = 79) and perceptual reasoning index (median PRI = 74) were higher.

CONCLUSION

With advanced treatment options, MPSI-H are living into 3rd and 4th decades of life, however not disease free and with poor adaptation. Residual disease (loss of mobility, limited gross and fine motor skills; low cognitive ability; suboptimal cardiopulmonary function, vision and hearing) negatively impacts the quality of life and psychosocial functioning of affected individuals.

Intrauterine Growth Restriction and Hypertrophic Cardiomyopathy as Prenatal Ultrasound Findings in a Case of Leprechaunism

Donohue syndrome (leprechaunism; OMIM *246200) is a rare and often lethal autosomal recessive disease caused by mutations in the INSR gene. We report the case of a 29-year-old pregnant woman, primigravida, who was referred at 33 weeks of gestation for severe intrauterine growth restriction (IUGR). Ultrasound examination found severe IUGR associated with an obstructive hypertrophic cardiomyopathy (HCM), confirmed postnatally. The newborn's blood glucose level fluctuated from fasting hypoglycemia to postprandial hyperglycemia. The infant was found to be homozygous for a novel missense pathogenic variant, c.632C>T (p.T211l), in exon 2 of the INSR gene, predicted to result in an abnormal insulin receptor. To our knowledge, this is the first report of leprechaunism being revealed by IUGR and HCM during the prenatal period. Clinicians should keep in mind that the association of these prenatal signs could indicate leprechaunism and specific early neonatal management could be proposed, in particular with recombinant human insulin-like growth factor-I.

P4646Prospective study for antenatal diagnosis of coarctation of the aorta

Material and methods

This prospective single-center study from 2010 to 2018 included all fetus diagnosed with isolated ventricular and/ or great vessels asymetry (right heart dominance). Complex CHD were excluded. The cohort was divided in patients with coarctation after birth (COA) and those free from coarctation (noCOA). Left heart, aortic and ductus measurements were collected serially at second trimester (T2), third trimester (T3) ad Z-scores were assessed. COA and noCOA were compared, sensitivity (Se) and specificity (Spec) and ROC curves (cut-off values) were assessed for each parameter.

Results

67 cases were included: 34 (50.7%) ranged in group COA and 33 (49.3%) in noCOA. Coarctation occurred more frequently if suspected at T2 (70.6% in COA vs 30.3% in noCOA, p=0.001). Mitral annulus (T3) was 8.6mm in COA vs 10.3mm in noCOA (p=0.002) with cut-off <7.3mm (Se= 50%, Spec= 93.6%, OR= 14.5). Aortic annulus diameter (T3) was 4.8mm in COA vs 6mm in noCOA (p=0.005), with cut-off <5.4mm (Se= 65%, Spec= 77%, OR= 6.3). Aortic isthmus diameter (T3) was 1.4mm in COA vs 2.8mm in noCOA (p=0.003), with cut-off <3mm (Se= 91%, Spec= 65%, OR= 18.9). Ductus arteriosus/ aortic isthmus ratio (T3) was 2.5 in COA vs 1.8 in noCOA (p=0.01) with cut-off >1.57mm (Se= 90.5%, Spec= 62%, OR= 15.4).

Conclusion

Mitral annulus <7.3mm, aortic annulus <5.4mm, aortic isthmus <3mm and ductus/isthmus ratio >1.57 assessed during 3rd trimester of fetal life may help to predict postnatal coractation of the aorta. These results have to be confirmed by larger prospective studies.

Outcomes of Newborns with Prenatal Ventricular Asymmetry not Requiring Neonatal Surgical Intervention: a 22-Year Retrospective Single-Center Study

To assess the outcomes of neonates prenatally diagnosed with ventricular asymmetry and not operated on within the neonatal period and to determine the risk factors for left heart obstruction occurrence at follow-up. All neonates with prenatal asymmetry of the ventricles, diagnosed from August 1993 to July 2015, not operated on within the neonatal period, were retrospectively included in the study. Left heart echocardiographic measurements at birth and at last follow-up were collected and compared. Left heart anomaly included isthmus and/or aortic valve and/or mitral valve obstruction. There were a total of 34 newborns included in the study. The median follow-up was 2 years. There was no death. Eleven patients were operated on at a median age of three months; seven of them had an obstruction of the left heart (five coarctations of the aorta, one sub-aortic and aortic valve stenosis, and one mitral stenosis). Estimated freedom of left heart surgery was 80% at 6 months and 75% at 10 years. The main risk factor for progression to a left heart anomaly was a hypoplasia of the aortic isthmus (p = 0.0003), while the presence of a left superior vena cava was more frequent in these patients although the difference was not significant. Patients with an aortic isthmus z-score below - 2 at the closure of arterial duct are at risk of later coarctation and therefore follow-up should be extended to at least 3 months. Furthermore, the prenatal ventricular asymmetry does not only identify patients at risk of coarctation but also of other left heart anomalies. This last point should be a better approach with future parents to improve prenatal counseling on a more complex postnatal diagnostic than a simple isolated coarctation.

Fetal right ventricular diverticulum with pericardial effusion: report of a new case treated by in utero pericardiocentesis

Right ventricular diverticulum associated with pericardial effusion was diagnosed in a male fetus at 13 weeks of gestation. Screening for infectious, chromosomal, or structural disease was negative. Because there was concern about pulmonary hypoplasia, fetal pericardiocentesis was performed at 17 weeks of gestation. The pericardial fluid did not reaccumulate, and the diverticulum decreased and finally disappeared before the third trimester. The diverticulum could not be seen on the neonatal echocardiography scan performed on the full-term live baby, who was delivered vaginally. The child is doing well at 11 months of age. Given the good outcome of this case, in utero drainage should be considered in similar cases.

[A rare cause of hyponatremia during introductory treatment of acute lymphoblastic leukemia in an infant: inappropriate secretion of atrial natriuretic factor?]

BACKGROUND

--Hyponatremia is frequently seen during the treatment of acute lymphoblastic leukemia: its causes are numerous. This work aims to present a case in whom hyponatremia was possibly due to an increased secretion of atrial natriuretic factor.

CASE REPORT

--A 3 week-old baby was admitted because of malignant hemopathy. A diagnosis of acute lymphoblastic leukemia was rapidly made and the patient was firstly given alkaline diuresis, urate-oxidase and corticosteroids. Vincristine and daunorubicin were associated one week later. Insertion of a central intravenous line in the right subclavicular artery failed so that this catheter was finally inserted into the left jugular vein. Natremia was 126 mmol/l at that time and dramatically decreased within 24 hours to 109 mmol/l without net changes in water and electrolytic input. At that time, sodium urinary excretion was 6 mmol/kg/day (diuresis: 420 mlF/day). There was no hemodynamic changes, nor digestive or cardiac manifestations. Ultrasonography showed that the left superior cava vein drained into the right cardiac atrium. The catheter was withdrawn and the patient was given sodium supplementation permitting complete and definitive cure of hyponatremia within 2 days.

CONCLUSIONS

--All usual causes of hyponatremia having been ruled out in this patient, we postulate that hyponatremia was due to direct stimulation of atrial natriuretic peptide through an increase in atrial pressure secondary to the catheter insertion near the cardiac atrium.