Hunter syndrome with its typical heart: a close mimic to rheumatic heart

Metabolic Cardiomyopathies and Cardiac Defects in Inherited Disorders of Carbohydrate Metabolism: A Systematic Review

Heart failure (HF) is a progressive chronic disease that remains a primary cause of death worldwide, affecting over 64 million patients. HF can be caused by cardiomyopathies and congenital cardiac defects with monogenic etiology. The number of genes and monogenic disorders linked to development of cardiac defects is constantly growing and includes inherited metabolic disorders (IMDs). Several IMDs affecting various metabolic pathways have been reported presenting cardiomyopathies and cardiac defects. Considering the pivotal role of sugar metabolism in cardiac tissue, including energy production, nucleic acid synthesis and glycosylation, it is not surprising that an increasing number of IMDs linked to carbohydrate metabolism are described with cardiac manifestations. In this systematic review, we offer a comprehensive overview of IMDs linked to carbohydrate metabolism presenting that present with cardiomyopathies, arrhythmogenic disorders and/or structural cardiac defects. We identified 58 IMDs presenting with cardiac complications: 3 defects of sugar/sugar-linked transporters (GLUT3, GLUT10, THTR1); 2 disorders of the pentose phosphate pathway (G6PDH, TALDO); 9 diseases of glycogen metabolism (GAA, GBE1, GDE, GYG1, GYS1, LAMP2, RBCK1, PRKAG2, G6PT1); 29 congenital disorders of glycosylation (ALG3, ALG6, ALG9, ALG12, ATP6V1A, ATP6V1E1, B3GALTL, B3GAT3, COG1, COG7, DOLK, DPM3, FKRP, FKTN, GMPPB, MPDU1, NPL, PGM1, PIGA, PIGL, PIGN, PIGO, PIGT, PIGV, PMM2, POMT1, POMT2, SRD5A3, XYLT2); 15 carbohydrate-linked lysosomal storage diseases (CTSA, GBA1, GLA, GLB1, HEXB, IDUA, IDS, SGSH, NAGLU, HGSNAT, GNS, GALNS, ARSB, GUSB, ARSK). With this systematic review we aim to raise awareness about the cardiac presentations in carbohydrate-linked IMDs and draw attention to carbohydrate-linked pathogenic mechanisms that may underlie cardiac complications.

Dermatologic manifestations of pediatric cardiovascular diseases: Skin as a reflection of the heart

Cutaneous disease can often be an initial clue of an underlying cardiovascular disease. Many congenital conditions (ie, Noonan syndrome with multiple lentigines, Carney complex, and Fabry disease) and acquired conditions may present initially with specific cutaneous features that should prompt clinicians to conduct a full cardiac workup. Given the extensive number of conditions with both cardiovascular and cutaneous findings, this review will focus on diseases with cardiocutaneous pathology with hopes of raising clinician awareness of these associations to decrease morbidity and mortality, as several of these diseases often result in fatal outcomes.

Efficacy of Idursulfase therapy in patients with Mucopolysaccharidosis type II who initiated enzyme replacement therapy in adult age. A systematic review of the literature

BACKGROUND

Enzyme replacement therapy (ERT) has been shown to decrease urine glycosaminoglycans (uGAGs) and liver and spleen volumes, and to improve clinical symptoms in mucopolysaccharidosis type II (MPS-II) patients.

METHODS

A systematic search of the literature, from inception to August 2017, was conducted to identify randomized trials or observational studies including ≥1 MPS-II patients with ERT initiated in adult age (≥16 years) and evaluating ERT efficacy. Evidence was rated according to GRADE criteria. Common efficacy outcomes of the clinical studies were analyzed. Case reports were separately evaluated.

RESULTS

One randomized clinical trial, 4 observational studies and 5 case reports were selected. ERT decreased uGAG levels and liver and spleen size with moderate evidence level and led to anti-ERT antibody and IRRS development in a significant proportion of patients with moderate evidence level. There were no conclusive results for beneficial effects on 6MWT, respiratory, cardiac and neurological function, joint mobility, sleep disorders of respiratory origin, and quality of life.

LIMITATIONS

Excluding one observational study, all others were not conducted specifically in the target population (ERT ≥16 years). Data were from subgroup analyses of selected studies. There was a great heterogeneity between study designs and clinical outcomes evaluated.

CONCLUSIONS

ERT improves uGAGs and liver/spleen volume with a moderate evidence level in MPS-II patients initiating therapy as adults, although the putative associated clinical benefit is unclear.

Cardiovascular Abnormalities in Egyptian Children with Mucopolysaccharidoses

INTRODUCTION

The Mucopolysaccharidoses (MPS) are rare inherited metabolic disorders. They are characterized by the progressive systemic deposition of Glycosaminoglycans (GAGs). GAGs accumulate in the myocardium and the cardiac valves. Enzyme Replacement Therapy (ERT) is available for MPS I, II, and VI. However, ERT does not appear to improve cardiac valve disease in patients with valve disease present at the start of ERT.

AIM

To evaluate the cardiac involvement in Egyptian children with MPS.

MATERIALS AND METHODS

Echocardiograms (ECG) were done for 34 patients. Both quantitative and qualitative Glycosaminoglycans (GAGs) in urine and enzyme assay confirmed the diagnosis. Mitral, tricuspid and aortic valves were evaluated for increased thickness, regurgitation and/or stenosis, left ventricular chamber dimensions, septal and posterior wall thicknesses.

RESULTS

The patients' age ranged from 0.9-16 years (median age 4 years). They included 19 cases of MPS I (55.9%), 3 cases of MPS II (8.8%), 2 cases of MPS III (5.9%), 6 cases of MPS IV (17.6%) and 4 cases of MPS VI (11.8%). Heart murmur was heard in 9 of the participants (9/34) (26%). However, 15 patients (15/34) (44%) revealed cardiac lesions on ECG examinations. Mitral regurge (47%), followed by pulmonary hypertension (40%), were the most frequent findings.

CONCLUSION

The absence of Cardiac murmurs does not exclude the heart involvement. Cardiac valve dysfunction may not be reversible. Regular ECG should be routinely warranted in children with MPS and early ERT are recommended.