The management and clinical outcomes of pregnancies in women with urea cycle disorders: A review of the literature and results of an international survey.

An increasing number of women with urea cycle disorders (UCDs) are reaching child-bearing age and becoming pregnant. Improved diagnostics and increased awareness of inherited metabolic diseases has also led to more previously undetected women being diagnosed with a UCD during or shortly after pregnancy. Pregnancy increases the risk of acute metabolic decompensation with hyperammonemia-which can occur in any trimester, and/or the postpartum period, and may lead to encephalopathy, psychosis, coma, and even death, if not diagnosed promptly and treated appropriately. There are also (theoretical) concerns that a maternal UCD, or its treatment, may cause potential risks for the unborn child. Currently evidence on management and outcome of pregnancies in UCDs is limited to case reports and there are no clear guidelines. In order to inform management and investigate outcomes of pregnancies in women with a UCD, we performed a retrospective review of published cases and analyzed data collected from an international online survey. We conclude that, although risk during the intra- and postpartum period exists, multidisciplinary management by an experienced team and a prospective plan usually result in successful pregnancy, labor, delivery, and postpartum period. No deaths were reported in mothers managed accordingly. With the exception of male neonates with Ornithine Transcarbamylase deficiency, the clinical outcome of children born to mothers with UCDs appears positive, although follow-up is limited. The outcome for women presenting with a first acute metabolic decompensation during pregnancy or postpartum is less favorable. Deaths were associated with diagnostic delay/late management of hyperammonemia in previously undiagnosed women.

The Impact of Phenylketonuria on Body Composition in Adults.

INTRODUCTION: Patients with phenylketonuria (PKU) must follow a lifelong phenylalanine (Phe)-restricted diet with additional amino acid supplementations, and this may put them at risk for nutritional disturbances. However, the body composition and nutritional status of adult patients with PKU has only been partially explored. The current study aims to assess the body composition of adult patients with PKU using multifrequency bioimpedance analysis (MF-BIA) and to reveal potential correlations between therapy adherence and body composition. Additionally, we compared body composition of patients with healthy controls. METHODS: Fifty adult patients with early-treated PKU (27 female and 23 male) and 40 healthy, age- and gender-matched controls were included in this single-center, cross-sectional study. MF-BIA was performed on all subjects. Additionally, we determined serum nutritional markers for all patients. In the PKU patient group, correlation analyses were performed between body composition parameters and therapy adherence. We compared body composition of patients with PKU and controls using BIA. RESULTS: The proportion of overweight was 56% among all patients with PKU. Female patients with PKU had significantly higher body fat percentage compared with controls. In parallel with higher fat content, we observed lower muscle mass, protein, and mineral content among female patients with PKU compared to controls. Such findings were not observed in male patients. Female patients with PKU had decreased therapy adherence and had significantly lower prealbumin levels compared with males. There was no significant correlation observed between body composition parameters and therapy adherence over the last 10 years in the PKU patient group. CONCLUSION: Although female patients had less optimal therapy adherence over the last 10 years compared with male patients, our results suggest that this does not influence body composition fundamentally. Our results suggest that obesity is an important comorbidity in young adult patients with PKU, especially in females. We advocate that nutritional assessments and weight management should be additional objectives of PKU management to provide optimal care.

The Association of Therapy Adherence and Thyroid Function in Adult Patients with Phenylketonuria.

BACKGROUND: The standard, lifelong therapy of phenylketonuria (PKU) is a natural protein-restricted diet complemented with phenylalanine (Phe)-free L-amino acid mixtures that provide the daily necessary micronutrients. OBJECTIVE: To assess thyroid function and structure and the iodine status of early-treated adult PKU (ETPKU) patients in Hungary. METHODS: Sixty-nine PKU patients (aged 18-41 years) and 50 healthy controls were enrolled in the study. Thyroid hormones, serum thyroglobulin, thyroid antibodies, urinary iodine, and selenium concentrations were measured, and thyroid ultrasound was performed. RESULTS: The incidence of thyroid dysfunction was infrequent (n = 2). Blood Phe was negatively correlated with thyroid-stimulating hormone (TSH), and PKU patients had higher free thyroxine and lower TSH levels than healthy controls. Although optimal iodine status was found in the entire PKU population, by dividing the patients according to their therapy compliance, we observed that lower therapy adherence was associated with mild iodine deficiency and lower urinary selenium levels. CONCLUSIONS: The results of this study suggest that iodine status is strongly influenced by the adherence to therapy in ETPKU patients. No or not enough medical food consumption combined with a low-Phe diet can lead to subclinical iodine deficiency.

[Adult phenylketonuria]. / Phenylketonuria felnottkorban.

Starting from 1975 phenylketonuria is part of the newborn screening program in Hungary. Since then a generation, treated with special diet and medical foods right after neonatal diagnosis has reached adulthood. Thanks to early treatment initiation, children with phenylketonuria are able to lead life to the full. Consequently, phenylketonuria is no longer considered a pediatric disease. Follow up of adult patients with phenylketonuria is performed in internal medicine centers specialized in metabolic diseases. The outcome of the lifelong special treatment, and the particularities of phenylketonuria in adulthood are yet to be determined. The aim of our review is to present recent findings in phenylketonuria focusing mainly on the adult care. After long time the first international guidelines appeared, new therapies were put in use, and these current developments are expected to be implemented in daily practice in the near future. New challenges must be met such as maternal phenylketonuria, long term effects of dietotherapy and the sequelae of untreated phenylketonuria in adulthood. Orv Hetil. 2017; 158(46): 1857-1863.

[Bone metabolism in adults with phenylketonuria - Hungarian data]. / Csontanyagcsere felnott phenylketonuriás pácienseknél ­ hazai adatok.

INTRODUCTION: Patients with phenylketonuria have lower bone mineral density compared to healthy people, however, the ethiology of these alterations is not clear. Hungarian data were missing in this topic. AIM: The main aim of our study was to survey the correlation between metabolic control and change of bone mineral density in early treated Hungarian adult patients with phenylketonuria. METHOD: In this monocentric study bone mineral density of 59 adult PKU patients have been repeatedly measured in a 4-year interval using dual-energy X-ray absorptiometry. Two subgroups have been established based on average blood phenylalanine levels. The correlation between the change in bone mineral density and average phenylalanine, tyrosine concentrations have been determined while initial bone mineral density and change have also been examined in the subgroups. RESULTS: Mean phenylalanine concentration was 614 (182-1222) micromol/L, whereas mean tyrosine concentration was 49 (24-99) micromol/L and the calculated ratio was 16 (4,5-35). Three patients have had severely decreased bone mineral density in either localisation while 22 have had mild decrease. Low bone mineral density compared to cronological age has been found by 9 patient. The mean change was +0.0380 (-0.1550-0.7800) g/cm2 in femur, and +0.0120 (-0.57300-0.3130) g/cm2 in the lumbar spine. There was a correlation in the change in Z-score neither with mean phenylalanine nor with tyrosine concentration. CONCLUSIONS: Bone mineral density was not changed and hardly influenced by the metabolic control in early-treated young adult phenylketonuria patients in a few years interval. Orv Hetil. 2017; 158(47): 1868-1872.

[Diet treatment of classical galactosemia]. / Klasszikus galactosaemia dietetikai kezelési lehetoségei.

Classical galactosemia is an inherited disorder of the carbohydrate metabolism, most often caused by the deficient activity of the enzyme galactose-1-phosphate-uridyltransferase. Classical galactosemia presents in the neonatal period with life threatening illness after galactose is introduced in the diet. Symptoms and signs include poor feeding, vomiting, and diarrhea, weight loss, jaundice, hypotension, cataracts, hepatosplenomegaly, hepatocellular insufficiency, and encephalopathy. Since 1975 the testing for galactosemia is part of the neonatal screening program in Hungary. Affected newborns are recognized in the first days of their life, and special diet is introduced immediately. The therapy of galactosemia is the lactose-free and galactose-poor diet for life. As a result of the nationwide newborn screening and the lifelong medical therapy, early treatment with galactosemia can achieve a normal life without serious complications. Orv Hetil. 2017; 158(47): 1864-1867.

[Williams-Beuren syndrome (Williams syndrome). Case report]. / Williams­Beuren-szindróma (Williams-szindróma).

Williams syndrome is a rare genetic disorder, that occurs equally in all ethnic groups and both sexes. The diagnosis might be missed during childhood in mild cases. However, establishing the diagnosis is important, not only to find the cause of intellectual disability but to look for cardiovascular, endocrine, psychiatry, urology and other conditions, which can occur at any age in the patients' lifetime. This case report presents the story of 47-year-old woman, who was admitted with haematemesis. During her stay on the ward, in the light of the distinctive facial features, mental retardation, and social behaviour patterns, the possibility of Williams syndrome emerged. Later, the diagnosis was confirmed by genetic analysis. This female is the oldest living patient with Williams syndrome in Hungary. Orv Hetil. 2017; 158(47): 1883-1888.

Genetic variants of the HSD11B1 gene promoter may be protective against polycystic ovary syndrome.

The HSD11B1 gene encodes the type 1 isoform of the 11-ß-hydroxysteroid dehydrogenase that is responsible for the regeneration of glucocorticoids from hormonally-inactive metabolites into active forms in a tissue-specific manner. Altered activity of the enzyme, and certain genetic variants of the HSD11B1 gene, has been associated with various metabolic morbidities. In this study, our aim was to systematically test the potential role of the HSD11B1's single nucleotide polymorphisms (SNPs) in polycystic ovary syndrome (PCOS). Nine HSD11B1 SNPs were selected and genotyped using Taqman SNP assays on real-time PCR in a group of PCOS patients (n = 58) and in age-matched healthy controls (n = 64). Genotype-phenotype correlations were determined and haplotype analysis was performed. An in silico prediction for potential transcription factor binding sites was also performed. Of the 5 promoter SNPs, 3 (rs760951; rs4844880; rs3753519) were less frequent in the PCOS group compared to healthy controls. SNPs rs4844880 and rs3753519 were in a complete linkage and the mutant haplotype (AA) was less frequent in the PCOS group. No association between HSD11B1 variants and clinical, pathological findings was observed in patients, but in healthy women the rs4844880 and the AA haplotype were associated with higher levels of homeostasis model assessment of beta cell function. The polymorphic form of the rs4844880 was predicted to bind Pbx-1. Promoter SNPs of the HSD11B1 gene might exert a potential genetic protective role against the development of PCOS, possibly via their beneficial effect on carbohydrate homeostasis due to facilitation of insulin efflux from pancreatic beta-cells.

Long-Term Renal Function in Adult Patients with Phenylketonuria.

INTRODUCTION: In phenylketonuria (PKU), toxic phenylalanine (Phe) can harm other organs beyond the brain. Furthermore, the lifelong therapy of PKU consists of consumption of increased amounts of amino-acid mixture that provoke hyperfiltration in the glomeruli. Therefore, the adherence to therapy in PKU might influence the long-term kidney function in PKU patients. METHODS: Data from 41 adult, early treated PKU patients were analyzed in this 10-year, retrospective, monocentric study. Two subgroups were created according to their therapy adherence: one with long-term blood Phe levels in the therapeutic range (<600 µmol/L), and one with suboptimal blood Phe levels. Renal function and metabolic parameters were collected over 10 years. Kidney function parameters were compared between the two groups and associations between blood Phe levels and kidney function were tested. RESULTS: After 10 years, serum creatinine levels (p = 0.369) and estimated glomerular filtration rate (eGFR) (p = 0.723) did not change significantly from baseline in the good therapeutic group. The suboptimal therapeutic group's eGFR decreased in the same period (from 110.4 ± 14 mL/min/1.73 m2 to 94.2 ± 16 mL/min/1.73 m2, p = 0.017). At 10 years, the suboptimal therapeutic group had an increased serum creatinine level (81 ± 14.4 µmol/L vs. 71.5 ± 13 µmol/L, p = 0.038), and a decreased eGFR (94.2 ± 16 mL/min/1.73 m2 vs. 103.3 ± 13 mL/min/1.73 m2p = 0.031) compared to the good adhering group. Significant negative correlation between Phe levels and eGFR (r = -0.41, p = 0.008) was observed. CONCLUSION: Long-term suboptimal therapy adherence in PKU patients with high blood Phe levels may lead to deterioration in kidney function.

Health-related quality of life in a european sample of adults with early-treated classical PKU.

BACKGROUND: Phenylketonuria (PKU) is a rare inborn error of metabolism affecting the catabolism of phenylalanine (Phe). To date, findings regarding health-related quality of life (HRQoL) in adults with early-treated classical PKU are discrepant. Moreover, little is known about metabolic, demographic, and cognitive factors associated with HRQoL. Hence, we aimed to investigate HRQoL and its association with demographic, metabolic, and cognitive characteristics in a large European sample of adults with early-treated classical PKU. RESULTS: This cross-sectional study included 124 adults with early-treated classical PKU from Hungary, Italy, Spain, Switzerland, and Turkey. All participants prospectively completed the PKU quality of life questionnaire (PKU-QoL), a questionnaire specifically designed to evaluate the impact of PKU and its treatment on HRQoL in individuals with PKU. In addition, information about Phe levels (concurrent and past year), demographic (age and sex), and cognitive variables (intelligence quotient, IQ) were collected. Most domains revealed little or no impact of PKU on HRQoL and more than three-quarters of the patients rated their health status as good, very good, or excellent. Nevertheless, some areas of concern for patients were identified. Patients were worried about the guilt that they experience if they do not adhere to the dietary protein restriction and they were most concerned about high Phe levels during pregnancy. Further, tiredness was the most affected symptom, and the supplements' taste was considered a main issue for individuals with PKU. The overall impact of PKU on HRQoL was higher in women (U = 1315.5, p = .012) and in adults with a lower IQ (rs = - 0.448, p = .005). The overall impact of dietary protein restriction was higher in adults with higher concurrent Phe levels (rs = 0.272, p = .007) and higher Phe levels during the past year (rs = 0.280, p = .009). CONCLUSION: The impact of PKU on most domains assessed in the PKU-QoL was considered to be low. These results likely reflect the successful implementation of the newborn screening resulting in the prevention of severe adverse long-term outcomes. However, a particular clinical focus should be given to patients with lower IQ, higher Phe levels, and women, as these variables were associated with a lower HRQoL.

[The role of methylglyoxal metabolism in type-2 diabetes and its complications]. / A metilglioxál metabolizmus szerepe 2-es típusú cukorbetegségben és szövodményeiben.

Transient or chronic hyperglycaemia increases the formation of intracellular reactive oxygen species and aldehydes. The accumulation of reactive aldehydes is implicated in the development of diabetic complications. Methylglyoxal, a glucose dependent α-dicarbonyl might be the most important reactive aldehyde in diabetes and its complications. Diabetes was the first disease in which evidence emerged for the increased formation of methylglyoxal in the cells and in the serum. Methylglyoxal has a toxic effect on insulin secretion from pancreatic beta-cells, and on modifications of proteins and nucleic acids. Moreover, methylglyoxal is one of the major precursors of advanced glycation end-products. The glyoxalase enzyme system that exists in all mammalian cells is catalyzing the detoxification of methylglyoxal. This review summarizes the methylglyoxal metabolism in normoglycaemic and hyperglycamic conditions and the role of methylglyoxal in the development of late diabetic microvascular complications.

Prognostic factors and mitotane treatment of adrenocortical cancer. Two decades of experience from an institutional case series.

Objectives: This study aimed to characterise the clinicopathological features and prognostic factors of a large cohort of Hungarian patients with adrenocortical cancer diagnosed between 2000-2021. Patients and methods: This retrospective study included seventy-four patients (27 men and 47 women) with histologically confirmed adrenocortical cancer in a single tertiary referral endocrine centre. Descriptive statistics were performed, providing summaries of selected clinical and pathological parameters. Clinicopathological factors contributing to overall survival were analysed. Results: The median age of patients was 48,5 years (17-84 years) at diagnosis. The majority of cases were diagnosed at ENSAT stage II (39,2%) and stage IV (33,8%). At diagnosis, the median tumour size was 9,0 cm (4,5-20 cm). In 47 patients (71,6%), the tumour was hormonally active. The median overall survival and the 5-year survival rate were 23,5 months (95% CI, 17-30,5 months) and 18,3%, respectively. Primary tumour resection was performed in 68 patients (91,8%); R0 surgical resection was achieved in 30 patients. In univariate Cox regression model, tumours with stages III and IV, high proliferative activity (Ki67-index > 10%), R1-R2 surgical resection state and hormonal activity were associated with poorer survival. Cortisol excess, both isolated and combined with androgen production, was associated with poorer survival. Fifty-five patients were treated with mitotane. The overall survival of patients achieving therapeutic mitotane plasma concentration was significantly better compared to those who never reached it [27.0 (2-175) months vs 18.0 (2-83) months; p<0.05)]. The median age, the distribution of gender, ENSAT stage, resection state and Ki67-index did not differ between these two groups. The time needed to reach the therapeutic range of serum mitotane was 96.5 days (95% CI, 75-133 days). Conclusion: Our results confirm previous data that disease stage, mitotic activity, the resection state and the mitotane treatment achieving therapeutic concentration are the most critical parameters influencing the prognosis of adrenocortical cancer. Our data suggest that hormonal activity may be more frequent than described previously, and it is a strong and independent prognostic factor of overall survival. To our knowledge, this is the first single-centre study confirming the prognostic importance of achieving therapeutic mitotane concentration.

[Study of the Toll-like receptor 4 gene polymorphisms in diseases presenting with subclinical and chronic inflammation]. / A Toll-like receptor-4-polimorfizmus vizsgálata szubklinikus és krónikus gyulladással járó betegségekben.

UNLABELLED: Toll-like receptor 4, a central mediator of the innate immune response has been shown to play an important role not only in the defense mechanism against microorganism, but also other non-infectious inflammatory diseases such as atherosclerosis. The Asp299Gly and Thr399Ile, which are common co-segregation polymorphisms of the Toll-like receptor 4 gene have been shown to be associated with increased susceptibility for Gram-negative infections, but with a lower risk of carotid atherosclerosis and a reduced level of certain proinflammatory cytokines. AIM: The role of these polymorphisms in diabetes mellitus with its late microvascular complications, in ischemic stroke, and in chronic periodontitis was investigated in three independent studies. METHODS: In all studies the alleles of both polymorphisms were detected by polymerase chain reaction and subsequent cleavage by restriction endonucleases followed by gel electrophoresis. RESULTS: In patients with type 2 diabetes, heterozygote carriers of the Asp299Gly and Thr399Ile polymorphisms of the Toll-like receptor 4 gene had a significantly reduced prevalence of peripheral neuropathy, while there was no association with any other diabetic microvascular complication, or with cerebral ischemia or with chronic periodontitis. CONCLUSIONS: Toll-like receptor 4 gene polymorphisms are not enough sensitive genetic markers for risk stratification either in diabetes mellitus or in cerebral ischemia or in chronic periodontitis.

[Diabetes and thyroid disorders]. / Cukorbetegség és pajzsmirigybetegségek.

Both diabetes mellitus and thyroid disorders are common diseases. According to epidemiologic studies the prevalence of specific thyroid disorders in diabetic subjects is two times higher. Risk factors are age, female gender and autoimmune diabetes mellitus. However, thyroid disorders are diagnosed only half of the cases in diabetic population. The review briefly summarizes the association of autoimmune diabetes mellitus and thyreoiditis, the risk of thyroid disorders in type 1 diabetic pregnant women. Furthermore, the influence of obesity in the risk on thyroid cancer and the effect of glucagon-like peptide 1 analogue on thyroid medullary C-cells are discussed.

[Somatostatin receptor endoradiotherapy of neuroendocrine tumors: experience in Hungarian patients]. / Neuroendokrin daganatok szomatosztatinreceptor-endoradioterápiája: hazai betegeken szerzett tapasztalatok.

Beside conventional therapies for the treatment of neuroendocrine tumors, a new therapeutical approach, peptide receptor radionuclide therapy has been developed recently. There are two important features which make this therapy feasible: somatostatin receptors are strongly over-expressed in most neuroendocrine tumors resulting in a high tumor-to-background ratio and internalization of the somatostatin-receptor complex in neuroendocrine cells. Due to these features, neuroendocrine tumors can be treated with radiolabelled somatostatin analogues. For peptide receptor radionuclide therapy, somatostatin analogues are conjugated to a chelator that can bind a radionuclide. The most frequently used radionuclides for neuroendocrine tumor treatment are the ß-emitter Yttrium-90 (9°Y) and the ß+γ emitter Lutetium-177 (¹77Lu). Candidates for somatostatin receptor endoradiotherapy are patients with progressive, metastatic, somatostatin-receptor positive neuroendocrine tumors. Many patients have been successively treated with this approach: according to international results major remission can be achieved in 25% of the cases. Although this therapy is still unavailable in Hungary, Hungarian patients can be treated with somatostatin receptor endoradiotherapy with financial support from the National Health Fund in a co-operation with the University of Basel since 2005. During the past 5 years, 51 Hungarian patients have been treated with this therapy. This review briefly summarizes the theoretical background, indications, effectiveness and side effects of somatostatin receptor endoradiotherapy and the authors present the first data obtained from Hungarian patients.

Complete Remission of Advanced Adrenocortical Cancer Following Mitotane Monotherapy: A Case Report and Literature Review of Predictive Markers.

Mitotane has been used for the treatment of adrenocortical cancer (ACC) for over 50 years. Despite its widespread use both in monotherapy and in combination with chemotherapeutics, our knowledge of its mechanism of action and therapeutic efficacy is scarce. The number of patients with advanced ACC who have achieved complete remission documented by detailed clinical data is below ten. We report a case of a 64-year-old woman with a non-functional ACC. Histological examination showed vascular invasion, Ki67 of 10% and a mitotic count of 3/10 high-power field. Immunohistochemistry revealed p53 positivity. Pathological TNM grade was reported as T2N0M0, ENSAT stage 2. Nine months after the initial diagnosis, re-staging CT revealed multiple peritoneal nodules, lymph node and kidney metastases confirmed by histologic examination. Mitotane monotherapy was started with a maintenance dose between 2.0 and 2.5 grams/day. Partial remission was established at six months. Subsequently, for another 12 months, each of the three-monthly CT scans confirmed complete remission. Nineteen months after the initiation of mitotane, an unexpected sudden death occurred. A detailed autopsy work-up, performed in the full awareness of oncological history, confirmed complete remission. The authors review the molecular biomarkers and clinical features reported as predictors of response to mitotane monotherapy.

Case Report: Complete Necrosis of a Large Adrenocortical Cancer and Liver Metastases Achieved by Selective Arterial Embolization: A Case Study and Review of Literature.

There is very limited experience regarding the interventional radiological treatment of adrenocortical cancer (ACC). We present the case of a 57-year-old female patient with a large, potentially unresectable left-sided ACC and two hepatic metastases. Both liver tumors were effectively treated by trans-arterial embolization (TAE), followed by TAE of the bulky primary tumor as a life-saving intervention necessitated by severe intratumoral bleeding. Surgical removal of the primary tumor revealed complete necrosis. The patient is considered tumor free after 3.5 years. To the best of our knowledge, this is the first report to show that even a primary ACC may be completely ablated by selective embolization, and the fourth to prove the curative potential of liver TAE for ACC metastases. This case highlights the potential of selective embolization in ACC treatment.

Reduced macular thickness and macular vessel density in early-treated adult patients with PKU.

PURPOSE: Macular structure is poorly evaluated in early-treated phenylketonuria (ETPKU). To evaluate potential changes, we aimed to examine retinas of PKU patients using optical coherence tomography (OCT) with additional OCT angiography (OCTA) and compare the results to healthy controls. METHODS: A total of 100 adults were recruited in this monocentric, case-control study: 50 patients with ETPKU (mean age: 30.66 ± 8.00 years) and 50 healthy controls (mean age: 30.45 ± 7.18 years). Macular thickness, vessel density and flow area of the right eye was assessed with spectral domain OCT angiography SD-OCT(A). Macular microstructural data between the ETPKU and control group was compared. In the ETPKU group, the relationship between visual functional parameters (best corrected visual acuity [VA], spherical equivalent [SE], contrast sensitivity [CS] and near stereoacuity) and microstructural alterations was examined. The dependency of OCT(A) values on serum phenylalanine (Phe) level was analysed. RESULTS: There was significant average parafoveal and perifoveal total retinal layer thinning in ETPKU patients compared to healthy controls (p < 0.016 and p < 0.001, respectively), while the foveal region remained unchanged in the ETPKU group. Whole macular and parafoveal superficial capillary plexus density was significantly decreased in ETPKU compared to controls (p < 0.001). There were no significant differences in the foveal avascular zone, nonflow area, macular superficial and deep capillary plexus between the groups. The temporal parafoveal inner retinal layer thickness was found to negatively correlate with individual Phe levels (r = -0.35, p = 0.042). There was no difference in vascular density and retinal thickness in the subgroup analysis of patients with good therapy adherence compared to patients on a relaxed diet. CONCLUSIONS: Durable elevation in Phe levels are only partially associated with macular retinal structural changes. However, therapy adherence might not influence these ophthalmological complications.

Altered visual functions, macular ganglion cell and papillary retinal nerve fiber layer thickness in early-treated adult PKU patients.

PURPOSE: Retinal changes are poorly described in early treated phenylketonuria (ETPKU). We aimed to investigate possible visual functional and ocular microstructural changes in adult patients with ETPKU. Optical coherence tomography (OCT) and its angiography (OCTA) data from patients with PKU were compared to healthy controls. METHODS: In this prospective, monocentric, cross-sectional, case-control study 50 patients with ETPKU and 50 healthy subjects were evaluated with OCT and OCTA. Measurements were performed on right eyes. The following visual function parameters were studied: best corrected visual acuity (BCVA), spherical equivalent (SE), contrast sensitivity and near stereoacuity; microstructural parameters: retinal nerve fiber layer thickness (RNFLT), ganglion cell layer (GCC) thickness, focal loss of volume (FLV), global loss of volume (GLV), peripapillary, papillary vessel density (VD), ocular axial length (AL) and intraocular pressure (IOP). RESULTS: Among functional tests there were significant differences in contrast sensitivity at 1.5 (p < 0.001), 6 (p < 0.013), 12 (p < 0.001), 18 (p < 0.003) cycles per degree, in near stereoacuity (Titmus Wirt circles, p < 0.001) and in best corrected visual acuity (BCVA, p < 0.001). A statistically significant, moderate positive linear correlation was observed between BCVA and average Phe levels over the last ten years (ß = 0.49, p < 0.001). The average (p < 0.001), superior (p < 0.001) inferior GCC (p < 0.001), the FLV (p < 0.003), GLV (p < 0.001) and the average RNFLT (p < 0.004) values of the PKU group were significantly lower than the controls. The serum phenylalanine level (Phe) in the PKU group negatively correlated with inferior (-0.32, p < 0.007), superior (r = -0.26, p < 0.028) and average (-0.29 p < 0.014) RNFL and with AL (-0.32, p < 0.026). In AL we detected a significant difference (p < 0.04) between the good and suboptimal dietary controlled group. There was no significant difference between the ETPKU and control group in the measured vessel density parameters and in IOP. CONCLUSIONS: Our results suggest that functional and ocular microstructural defects are present in patients with PKU, and some of them may depend on dietary control. The mechanism is unclear, but the correlation indicates the importance of strict dietary control in terms of preservation of retinal functions.