Mortality in Pedigrees with Acute Intermittent Porphyria

High mortality rates have been reported in historical cohorts of acute intermittent porphyria (AIP) patients. The mortality associated with (hydroxymethylbilane synthase) HMBS variant heterozygosity is unknown. This study estimates all-cause mortality in pedigrees with HMBS gene variants that cause AIP. We collected data on the lifespan of individuals in Dutch AIP pedigrees and performed analyses using the family tree mortality ratio method. This gave us standardized mortality ratios for these pedigrees compared to the Dutch general population as a primary outcome. Between 1810 and 2017, the overall mortality in these pedigrees was identical to that of the general Dutch population: (SMR 1.01, p = 0.441). However, compared with the general population the SMR was significantly higher in women aged 45–64 years (SMR 1.99, p = 0.00003), which was based on excess mortality between 1915 and 1964 (SMR 1.94, p < 0.00002). In men aged 70–74 years, the SMR was 1.55 (p = 0.0021), based on excess mortality that occurred between 1925 and 1964 (SMR 1.92, p = 0000000003). Overall, mortality from HMBS variant heterozygosity was not increased compared with the general population. Severe excess mortality occurred in young women and old men between 1915 and 1964. Heterozygotes reached a normal lifespan during the past half-century, in parallel with disease awareness and the prevention of new attacks through family counselling

Quality of life in children with erythropoietic protoporphyria:a case-control study

Erythropoietic protoporphyria (EPP) is an inherited metabolic disease that causes painful phototoxic reactions, starting in childhood. Studies have shown a reduced quality of life (QoL) in adults with EPP, however, data on children with the disease are lacking. Since treatment for EPP is currently not registered for children, knowledge about their QoL is of crucial importance. In this prospective, case–control study, we included children from the Netherlands and Belgium diagnosed with EPP and matched to healthy controls. Previously collected EPP quality of life (EPP-QoL) data from matched adults with EPP were used. QoL scores, utilizing the Pediatric Quality of Life Inventory (PedsQL) and the disease-specific EPP-QoL, were collected. Scores range from 0 to 100, with higher scores indicating a higher QoL. Non-parametric tests were used to compare groups. A total of 15 cases, 13 matched healthy control children, and 15 matched adults with EPP were included. Children with EPP exhibited lower median scores in the PedsQL in both physical (cases: 87.5 (interquartile range [IQR] 77.7–96.1), controls: 99.2 [IQR 94.9–100.0], p = 0.03) and social (cases: 77.5 [IQR 69.4–86.3], controls: 97.5 [IQR 78.8–100.0], p = 0.04) domains compared to healthy children, although these differences were not statistically significant after correcting for multiple testing. The overall median EPP-QoL score for children was similar to adults with EPP (children: 44.4 [IQR 25.0–54.2], adults: 45.8 [IQR 25.7–68.1], p = 0.68). However, within the EPP-QoL subdomain on QoL, children were found to have significantly lower median scores (children: 16.7 [IQR 0.0–33.3], adults: 33.3 [IQR 33.3–62.5], p &lt; 0.01). In conclusion, children with EPP experience a reduced QoL compared to both healthy children and adults with EPP. Ensuring treatment availability for this patient group is crucial for improving their QoL. We advocate the inclusion of children in safety and efficacy studies, to ensure availability of treatment in the future.</p

Quality of life in children with erythropoietic protoporphyria:a case-control study

Erythropoietic protoporphyria (EPP) is an inherited metabolic disease that causes painful phototoxic reactions, starting in childhood. Studies have shown a reduced quality of life (QoL) in adults with EPP, however, data on children with the disease are lacking. Since treatment for EPP is currently not registered for children, knowledge about their QoL is of crucial importance. In this prospective, case–control study, we included children from the Netherlands and Belgium diagnosed with EPP and matched to healthy controls. Previously collected EPP quality of life (EPP-QoL) data from matched adults with EPP were used. QoL scores, utilizing the Pediatric Quality of Life Inventory (PedsQL) and the disease-specific EPP-QoL, were collected. Scores range from 0 to 100, with higher scores indicating a higher QoL. Non-parametric tests were used to compare groups. A total of 15 cases, 13 matched healthy control children, and 15 matched adults with EPP were included. Children with EPP exhibited lower median scores in the PedsQL in both physical (cases: 87.5 (interquartile range [IQR] 77.7–96.1), controls: 99.2 [IQR 94.9–100.0], p = 0.03) and social (cases: 77.5 [IQR 69.4–86.3], controls: 97.5 [IQR 78.8–100.0], p = 0.04) domains compared to healthy children, although these differences were not statistically significant after correcting for multiple testing. The overall median EPP-QoL score for children was similar to adults with EPP (children: 44.4 [IQR 25.0–54.2], adults: 45.8 [IQR 25.7–68.1], p = 0.68). However, within the EPP-QoL subdomain on QoL, children were found to have significantly lower median scores (children: 16.7 [IQR 0.0–33.3], adults: 33.3 [IQR 33.3–62.5], p &lt; 0.01). In conclusion, children with EPP experience a reduced QoL compared to both healthy children and adults with EPP. Ensuring treatment availability for this patient group is crucial for improving their QoL. We advocate the inclusion of children in safety and efficacy studies, to ensure availability of treatment in the future.</p

The effects of cholecalciferol and afamelanotide on vitamin D levels in erythropoietic protoporphyria:a multicentre cohort study

Background: Patients with erythropoietic protoporphyria experience lifelong painful photosensitivity resulting in a lack of sunlight exposure. Previous studies have shown that 47-63% of patients with EPP suffer from vitamin D deficiency and a high prevalence of osteoporosis. An effective treatment for EPP has been available since 2016: the α-melanocyte stimulating hormone analogue afamelanotide. So far, studies on vitamin D levels in EPP have only investigated patients who have not been treated with afamelanotide. Objectives: To investigate the effects of afamelanotide treatment on vitamin D levels in EPP. Methods: A multicentre observational cohort study in adults with EPP from the Erasmus Medical Centre, the Netherlands, and the University Hospital Düsseldorf, Germany, was carried out. Routinely collected vitamin D levels between 2005 and 2021 were used for analysis. Patient exposure to cholecalciferol or afamelanotide was categorized into four treatment groups: untreated, cholecalciferol, afamelanotide and combined treatment. A linear mixed model for longitudinal data was applied to measure the effect of the treatment groups compared with the untreated groups on vitamin D levels. Results: A total of 230 patients and 1774 vitamin D measurements were included. The prevalence of vitamin D deficiency and severe deficiency remained high despite afamelanotide treatment (&lt; 50 nmol L-1 in 71.8% of patients and &lt; 30 nmol L-1 in 48.1%, respectively). Afamelanotide treatment alone did not lead to a significant average increase in vitamin D levels [β = 0.5, 95% confidence interval (CI) -3.2 to 4.2]. In contrast, cholecalciferol and combined therapy with afamelanotide led to a significant increase in vitamin D levels [β = 11.6 (95% CI 7.2-15.9) and β = 15.2 (95% CI 12.3-18.1), respectively].Conclusions: Cholecalciferol remains essential for the treatment of vitamin D deficiency in EPP, irrespective of new treatment options like afamelanotide. Afamelanotide treatment did not affect vitamin D levels. We suggest that future guidelines include continuous monitoring of vitamin D and a prescription for cholecalciferol in all patients with EPP, including those treated with afamelanotide.</p

Orofacial abnormalities in mucopolysaccharidosis and mucolipidosis type II and III:A systematic review

Mucopolysaccharidoses (MPSs) and mucolipidosis II and III (ML II and III) often manifest with orofacial (progressive) abnormalities, which may have a major impact on quality of life. However, because these patients have multiple somatic health issues, orofacial problems are easily overlooked in clinical practice and available literature on this topic solely consists of case reports, small case series, and small cohort studies. The aim of this systematic review was to gain more insight in the nature and extent of orofacial abnormalities in MPS, ML II, and III. A systematic review of all previously published articles addressing orofacial abnormalities in MPS, ML II, and III was performed. Both clinical studies and case reports were included. Outcome was the described orofacial abnormalities, subdivided into abnormalities of the face, maxilla, mandible, soft tissues, teeth, and occlusion. The search resulted in 57 articles, describing orofacial features in 340 patients. Orofacial abnormalities were present in all subtypes of MPS, ML II, and III, and consisted of thickened lips, a hypoplastic midface, a high‐arched palate, hypoplastic condyles, coronoid hyperplasia, macroglossia, gingival hyperplasia, thick dental follicles, dentigerous cysts, misshapen teeth, enamel defects, and open bite. Orofacial abnormalities are present in all subtypes of MPS, ML II, and III. As orofacial abnormalities may cause complaints, evaluation of orofacial health should be part of routine clinical care

Decreased Aerobic Exercise Capacity After Long-Term Remission From Cushing Syndrome: Exploration of Mechanisms.

BACKGROUND: Although major improvements are achieved after cure of Cushing syndrome (CS), fatigue and decreased quality of life persist. This is the first study to measure aerobic exercise capacity in patients in remission of CS for more than 4 years in comparison with matched controls, and to investigate whether the reduction in exercise capacity is related to alterations in muscle tissue. METHODS: Seventeen patients were included. A control individual, matched for sex, estrogen status, age, body mass index, smoking, ethnicity, and physical activity level was recruited for each patient. Maximal aerobic capacity (VO2peak) was assessed during incremental bicycle exercise to exhaustion. In 8 individually matched patients and controls, a percutaneous muscle biopsy was obtained and measures were made of cross-sectional areas, capillarization, and oxphos complex IV (COXIV) protein content as an indicator of mitochondrial content. Furthermore, protein content of endothelial nitric oxide synthase (eNOS) and eNOS phosphorylated on serine1177 and of the NAD(P)H-oxidase subunits NOX2, p47phox, and p67phox were measured in the microvascular endothelial layer. FINDINGS: Patients showed a lower mean VO2peak (SD) (28.0 [7.0] vs 34.8 [7.9] ml O2/kg bw/min, P < .01), maximal workload (SD) (176 [49] vs 212 [67] watt, P = .01), and oxygen pulse (SD) (12.0 [3.7] vs 14.8 [4.2] ml/beat, P < .01) at VO2peak. No differences were seen in muscle fiber type-specific cross-sectional area, capillarization measures, mitochondrial content, and protein content of eNOS, eNOS-P-ser1177, NOX2, p47phox, and p67phox. INTERPRETATION: Because differences in muscle fiber and microvascular outcome measures are not statistically significant, we hypothesize that cardiac dysfunction, seen in active CS, persists during remission and limits blood supply to muscles

Extending diagnostic practices in gyrate atrophy:Enzymatic characterization and the development of an in vitro pyridoxine responsiveness assay

Gyrate atrophy of the choroid and retina (GACR) is caused by pathogenic biallelic variants in the gene encoding ornithine-δ-aminotransferase (OAT), and is characterized by progressive vision loss leading to blindness. OAT is a pyridoxal-5′-phosphate (PLP) dependent enzyme that is mainly involved in ornithine catabolism, and patients with a deficiency develop profound hyperornithinemia. Therapy is aimed at lowering ornithine levels through dietary arginine restriction and, in some cases, through enhancement of OAT activity via supraphysiological dosages of pyridoxine. In this study, we aimed to extend diagnostic practices in GACR by extensively characterizing the consequences of pathogenic variants on the enzymatic function of OAT, both at the level of the enzyme itself as well as the flux through the ornithine degradative pathway. In addition, we developed an in vitro pyridoxine responsiveness assay. We identified 14 different pathogenic variants, of which one variant was present in all patients of Dutch ancestry (p.(Gly353Asp)). In most patients the enzymatic activity of OAT as well as the rate of [14C]-ornithine flux was below the limit of quantification (LOQ). Apart from our positive control, only one patient cell line showed responsiveness to pyridoxine in vitro, which is in line with the reported in vivo pyridoxine responsiveness in this patient. None of the patients harboring the p.(Gly353Asp) substitution were responsive to pyridoxine in vivo or in vitro. In silico analysis and small-scale expression experiments showed that this variant causes a folding defect, leading to increased aggregation properties that could not be rescued by PLP. Using these results, we developed a diagnostic pipeline for new patients suspected of having GACR. Adding OAT enzymatic analyses and in vitro pyridoxine responsiveness to diagnostic practices will not only increase knowledge on the consequences of pathogenic variants in OAT, but will also enable expectation management for therapeutic modalities, thus eventually improving clinical care.</p

Successful adult domino living donor liver transplantation in methylmalonic acidemia:case report

Background: Liver transplantation (LT) is a therapeutic option in multiple inherited metabolic diseases (IMDs), including methylmalonic acidemia (MMA), as LT reduces the risk of acute metabolic decompensations and long-term complications associated with these diseases. In certain IMDs, such as maple syrup urine disease (MSUD), domino liver transplant (DLT) is an accepted and safe method which expands the donor pool. However, only one adult case of DLT using an MMA donor liver has been reported; outcome and safety are still unknown and questioned. Case Description: In this case report, we describe our experience with DLT using MMA livers. Two adult MMA patients underwent living donor liver transplant (LDLT); their MMA livers were consecutively transplanted into two patients on the liver transplant waiting list who had limited chance of receiving a liver transplant in the short term due to their low model for end-stage liver disease (MELD) scores. No severe peri- or postoperative complications occurred, however the recipients of the MMA livers biochemically now have mild MMA. Conclusions: DLT using MMA grafts is a feasible strategy to treat end-stage liver disease and expand the donor organ pool. However, the recipient of the MMA domino liver may develop mild MMA which could affect quality of life, and long-term safety remains unclear. Further long-term of outcomes for domino recipients of MMA livers, focusing on quality of life and any metabolic complications of transplantation are needed to better define the risks and benefits

Successful adult domino living donor liver transplantation in methylmalonic acidemia:case report

Background: Liver transplantation (LT) is a therapeutic option in multiple inherited metabolic diseases (IMDs), including methylmalonic acidemia (MMA), as LT reduces the risk of acute metabolic decompensations and long-term complications associated with these diseases. In certain IMDs, such as maple syrup urine disease (MSUD), domino liver transplant (DLT) is an accepted and safe method which expands the donor pool. However, only one adult case of DLT using an MMA donor liver has been reported; outcome and safety are still unknown and questioned. Case Description: In this case report, we describe our experience with DLT using MMA livers. Two adult MMA patients underwent living donor liver transplant (LDLT); their MMA livers were consecutively transplanted into two patients on the liver transplant waiting list who had limited chance of receiving a liver transplant in the short term due to their low model for end-stage liver disease (MELD) scores. No severe peri- or postoperative complications occurred, however the recipients of the MMA livers biochemically now have mild MMA. Conclusions: DLT using MMA grafts is a feasible strategy to treat end-stage liver disease and expand the donor organ pool. However, the recipient of the MMA domino liver may develop mild MMA which could affect quality of life, and long-term safety remains unclear. Further long-term of outcomes for domino recipients of MMA livers, focusing on quality of life and any metabolic complications of transplantation are needed to better define the risks and benefits