Cardiac involvement (CI) in phosphomannomutase 2-congenital disorders of glycosylation (PMM2-CDG) is part of the multisystemic presentation contributing to high mortality rates. The most common cardiac manifestations are pericardial effusion, cardiomyopathy, and structural heart defects. A genotype-phenotype correlation with organ involvement has not yet been described. We analyzed clinical, biochemical, and molecular genetic data of 222 patients from eight European centers and characterized the natural course of patients with CI. Fifty-seven patients (45 children) presented with CI, of whom 24 died (median age 21 months, standard deviation 49.8). Pericardial effusion was the most frequent manifestation (55.4%), occurring mostly within the first 6 months of life. The most common pathogenic variants in patients with CI were p.(Arg141His) in 74%, followed by p.(Val231Met) in 36%, which is 3.5 times higher than in PMM2-CDG patients without CI (p < 0.0001). Twenty-one out of 36 patients with p.(Val231Met) had CI; among them, 15 died, compared to 33 out of 166 patients without p.(Val231Met) who had CI (p < 0.0001). Nine out of 33 patients died (p = 0.0015), indicating greater clinical severity. Furthermore, the p.(Val231Met) variant is predominant in Eastern Europe, suggesting a founder effect. Cardiac complications in PMM2-CDG patients are common and serious. The variant p.(Val231Met) profoundly influences the extent of CI and mortality rates. Therefore, we recommend cardiac surveillance be included in the follow-up protocols for PMM2-CDG.
- MeSH
- dítě MeSH
- fenotyp * MeSH
- fosfotransferasy (fosfomutasy) * genetika nedostatek MeSH
- genetické asociační studie MeSH
- kardiomyopatie genetika MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mutace MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- stupeň závažnosti nemoci MeSH
- vrozené poruchy glykosylace * genetika MeSH
- Check Tag
- dítě MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- novorozenec MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- multicentrická studie MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Evropa MeSH
Phosphomannomutase 2 (PMM2-CDG) is the most common congenital disorder of N-glycosylation and is caused by a deficient PMM2 activity. The clinical presentation and the onset of PMM2-CDG vary among affected individuals ranging from a severe antenatal presentation with multisystem involvement to mild adulthood presentation limited to minor neurological involvement. Management of affected patients requires a multidisciplinary approach. In this article, a systematic review of the literature on PMM2-CDG was conducted by a group of international experts in different aspects of CDG. Our managment guidelines were initiated based on the available evidence-based data and experts' opinions. This guideline mainly addresses the clinical evaluation of each system/organ involved in PMM2-CDG, and the recommended management approach. It is the first systematic review of current practices in PMM2-CDG and the first guidelines aiming at establishing a practical approach to the recognition, diagnosis and management of PMM2-CDG patients.
PURPOSE: PMM2-CDG is the most common congenital disorder of glycosylation (CDG), which presents with either a neurologic or multisystem phenotype. Little is known about the longitudinal evolution. METHODS: We performed data analysis on PMM2-CDG patients' clinical features according to the Nijmegen CDG severity score and laboratory data. Seventy-five patients (28 males) were followed up from 11.0 ± 6.91 years for an average of 7.4 ± 4.5 years. RESULTS: On a group level, there was no significant evolution in overall clinical severity. There was some improvement in mobility and communication, liver and endocrine function, and strabismus and eye movements. Educational achievement and thyroid function worsened in some patients. Overall, the current clinical function, the system-specific involvement, and the current clinical assessment remained unchanged. On follow-up there was improvement of biochemical variables with (near) normalization of activated partial thromboplastin time (aPTT), factor XI, protein C, antithrombin, thyroid stimulating hormone, and liver transaminases. CONCLUSION: PMM2-CDG patients show a spontaneous biochemical improvement and stable clinical course based on the Nijmegen CDG severity score. This information is crucial for the definition of endpoints in clinical trials.
- MeSH
- dítě MeSH
- fenotyp MeSH
- fosfotransferasy (fosfomutasy) nedostatek MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- následné studie MeSH
- předškolní dítě MeSH
- progrese nemoci MeSH
- vrozené poruchy glykosylace epidemiologie patofyziologie MeSH
- Check Tag
- dítě MeSH
- lidé MeSH
- mladiství MeSH
- mladý dospělý MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Úvod: Deficit fosfomanomutázy 2 (PMM2-CDG) je nejčastějším typem poruch N-glykosylace s popsanými >900 pacienty. Onemocnění je autosomálně recesivně dědičné a biochemickou podstatou je porucha přeměny manóza-6-fosfátu na manóza-1-fosfát (M1P). Onemocnění se projevuje encefalopatií, neuropatií, typickou dysmorfií, atrofií mozečku a koagulopatií. Práce prezentuje výsledky klinických, biochemických a molekulárních vyšetření pacientů diagnostikovaných v ČR. Výsledky: Od roku 2002 bylo v ČR diagnostikováno 22 pacientů z 18 rodin. Dvě děti zemřely v kojeneckém věku. Věk žijících 20 pacientů je v rozpětí 9 měsíců až 29 let (medián 14 let). U všech pacientů je přítomný hypotonický a mozečkový syndrom, strabismus, deformity skeletu, koagulopatie a mentální retardace, která je v pásmu od lehkého až po hluboké postižení. U 94 % pacientů jsme prokázali atrofii mozečku. Typická dysmorfie (atypické rozložení tuku a vpáčení bradavek) byla zjištěna u 82 % dětí. U 9 pacientů se projevila epilepsie a 3 pacienti prodělali iktu podobné příhody. Isoelektrická fokusace transferinu v séru prokázala u všech pacientů zvýšené zastoupení nízkosialovaných forem. Diagnóza byla potvrzena enzymologicky detekcí snížené aktivity PMM2 v lymfocytech či fibroblastech a/nebo molekulárně-geneticky. V našem souboru pacientů bylo zastoupeno 10 mutací v genu PMM2, všichni pacienti jsou složení heterozygoti a 71 % mutovaných alel neslo jednu ze dvou prevalentních patogenních variant (c.422G>A, c.338C>T). Závěr: S ohledem na odhadovanou incidenci PMM2-CDG 1:20 000 se jedná o onemocnění v ČR poddiagnostikované. PMM2-CDG patří do diferenciální diagnostiky všech dětí s atrofií mozečku, a to i bez přítomnosti charakteristických dysmorfických rysů. V plánu je zařazení českých pacientů do prospektivní multicentrické mezinárodní studie hodnotící přirozený průběh onemocnění a eventuálně zařazení do klinické studie s novou experimentální léčebnou molekulou LipoM1P (manóza-1-fosfát inkorporovaná do liposomu).
Introduction: PMM2-CDG is the most common autosomal recessive N-glycosylation disorder with more than 900 patients described worldwide. It is caused by a deficiency of the phosphomannomutase 2 enzyme (PMM2) which catalyzes the second step of the mannose pathway, namely the conversion of mannose-6-phosphate to mannose-1-phosphate. The clinical presentation is characterised by encephalopathy, neuropathy, typical dysmorphism, cerebellar atrophy and coagulopathy. We present the results of clinical, biochemical and molecular analyses in patients diagnosed in the Czech Republic. Results: Since 2002, a total of 22 Czech patients from 18 families with PMM2 deficiency have been diagnosed. The age range of the patients spans from 9 months to 29 years with a median of 14 years, except two patients who died during infancy. Muscle hypotonia, intellectual disability of varying severity, strabismus, ataxia, bone deformities, and coagulopathy were observed in all patients. Cerebellar atrophy was documented in 94% of the investigated patients. The characteristic dysmorphism (inverted nipples and atypical fat pads) were present in 82% of the patients. Nine patients suffered from seizures, and three patients showed transient neurological deterioration after stroke-like episodes. In all the patients, increased amount of hypoglycosylated transferrin was found by isoelectric focusing. The diagnosis of the PMM2-CDG was confirmed at enzymatic and/or at molecular levels. Molecular analyses revealed that all patients are compound heterozygotes for a total of 10 different mutations in PMM2, and that 71% of our patients´ alleles have one of the two most frequent genetic variants (c.422G>A, c.338C>T). Conclusion: The estimated incidence of PMM2-CDG is 1:20,000, suggesting that this disorder is underdiagnosed in the Czech Republic. PMM2-CDG must be considered in differential diagnosis of patients with cerebellar atrophy even if they do not manifest characteristic dysmorphism. We plan to include our patients in a longitudinal international multicenter observational study and potentially the upcoming clinical trial with LipoM1P (lipomised mannose-1-phosphate).
- Klíčová slova
- atrofie mozečku,
- MeSH
- dědičné koagulopatie diagnóza patologie MeSH
- dítě MeSH
- dospělí MeSH
- fosfotransferasy (fosfomutasy) * nedostatek MeSH
- genetické techniky MeSH
- isoelektrická fokusace MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mozeček patologie MeSH
- předškolní dítě MeSH
- retrospektivní studie MeSH
- vrozené poruchy glykosylace * diagnóza komplikace patofyziologie MeSH
- Check Tag
- dítě MeSH
- dospělí MeSH
- kojenec MeSH
- lidé MeSH
- mladiství MeSH
- mužské pohlaví MeSH
- předškolní dítě MeSH
- ženské pohlaví MeSH
- Publikační typ
- práce podpořená grantem MeSH
- přehledy MeSH
We report on the seventh known patient with S-adenosylhomocysteine hydrolase (SAHH) deficiency presenting at birth with features resembling phosphomannomutase 2 (PMM2-CDG Ia) deficiency. Plasma methionine and total homocysteine levels were normal at 2 months and increased only after the 8th month of age. SAHH deficiency was confirmed at 4.5 years of age by showing decreased SAHH activity (11% in both erythrocytes and fibroblasts), and compound heterozygosity for a known mutation c.145C>T (p.R49C) and a novel variant c.211G>A (p.G71S) in the AHCY gene. Retrospective analysis of clinical features revealed striking similarities between SAHH deficiency and the PMM2-CDG Ia.
- MeSH
- adenosylhomocysteinasa nedostatek genetika MeSH
- diferenciální diagnóza MeSH
- erytrocyty enzymologie patologie MeSH
- fibroblasty enzymologie patologie MeSH
- fosfotransferasy (fosfomutasy) nedostatek MeSH
- heterozygot MeSH
- homocystein krev MeSH
- lidé MeSH
- methionin krev MeSH
- mutace * MeSH
- novorozenec MeSH
- vrozené poruchy glykosylace diagnóza MeSH
- Check Tag
- lidé MeSH
- novorozenec MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
