Resilience strengthening in youth with a chronic medical condition: a randomized controlled feasibility trial of a combined app and coaching program.

Youth with a chronic medical condition (CMC) are often affected by comorbid mental disorders. Resilience-strengthening interventions can protect youth's mental health, yet evidence-based programs remain scarce. To address this lack, this study aimed to evaluate the feasibility of a dual approach combining app-based resilience training and cognitive behavioral group coaching. Fifty-one youths with CMC treated at a German university children's hospital aged 12-16 years were recruited. They were randomly assigned to a combined app game and coaching intervention or sole app gameplay. At pre-, post-intervention, and at a 2-month follow-up resilience, automatic negative thoughts and an app and coaching evaluation were assessed. Feasibility was defined as a recruitment rate of 70%, an 85% adherence rate for the REThink game, and 70% participation in both coaching sessions. Feasibility criteria were reached for coaching participation but not for recruitment or app adherence. While both the REThink game app and coaching intervention had high acceptance rates among youth with CMC, participants receiving additional coaching sessions showed higher satisfaction and adherence rates. Participants preferred remote to in-person meetings. The findings support a combination of a gamification app approach with online group coaching. Group coaching can improve adherence while online options increase accessibility. Future research should focus on testing in diverse participant samples, language, and age-adapted updates of the REThink game app. These findings provide guidance for increasing adherence in future intervention studies in youth with CMC cohorts.

Evaluation of lipoprotein-associated phospholipase A2 as a marker for renal microvasculopathy in adolescents with Type 1 diabetes.

AIM: To assess the relevance of lipoprotein-associated phospholipase A2 activity as a diagnostic and prognostic marker for renal microvascular diseases. METHODS: We analysed lipoprotein-associated phospholipase A2 activity and lysophosphatidylcholine levels (as a surrogate marker of oxidative stress) in 165 adolescents (aged 17.0 ± 2.3 years) with a history of Type 1 diabetes greater than 10 years. Clinical data were obtained from the German/Austrian nationwide Diabetes-Patients Follow-up (DPV) registry at blood collection and on average 2.4 ± 1.3 years later at follow-up. Relationships between lipoprotein-associated phospholipase A2 activity and clinical, demographic and laboratory variables, lysophosphatidylcholine levels and presence of albuminuria were evaluated by multivariable linear and logistic regression. RESULTS: Lipoprotein-associated phospholipase A2 activity was higher in male than female adolescents (P = 0.002). Albuminuria was present in 14% (22/158) of participants at baseline, and 5% (4/86) of participants without albuminuria at baseline developed albuminuria until follow-up. Lipoprotein-associated phospholipase A2 activity was associated neither with present nor with incident albuminuria. Lysophosphatidylcholine did not correlate with lipoprotein-associated phospholipase A2 activity. Cross-sectional bivariate correlation as well as multivariable linear regression analysis revealed a negative correlation of lipoprotein-associated phospholipase A2 activity with HbA1c and HDL-cholesterol. CONCLUSIONS: Lipoprotein-associated phospholipase activity was not associated with surrogate markers for oxidative stress and early diabetic nephropathy. The association of decreased lipoprotein-associated phospholipase A2 activity with poor glucose control might limit its function as a predictor of micro- and macrovascular diseases in Type 1 diabetes.

Need for Better Diabetes Treatment: The Therapeutic Potential of NMDA Receptor Antagonists.

Diabetes mellitus is the most common metabolic disorder in children and adolescents. Optimal control of blood glucose concentration is essential to prevent acute and diabetic long-term complications. The options to treat diabetes have clearly improved over the last decades, however, to date neither type 1 diabetes nor type 2 diabetes mellitus can be cured. Therefore, diabetes research aims at developing ß-cell protective agents that prevent or even reverse diabetes onset. N-methyl-D-aspartate receptors (NMDARs) are glutamate-gated ion channels that are widely expressed in the central nervous system (CNS) where they hold central roles in CNS function. NMDAR dysfunction is associated with several neurological and psychiatric disorders and therefore NMDAR modulators have several potential therapeutic indications. Only little is known about the role of pancreatic NMDA receptors. Our data provide evidence that inhibition of pancreatic NMDARs, either genetically or pharmacologically with the over-the-counter drug dextromethorphan, increases glucose-stimulated insulin secretion from mouse and human pancreatic islets, improves glucose tolerance in mice and individuals with diabetes and promotes islet cell survival under diabetogenic conditions. Thus, our data indicate for the first time that NMDAR antagonists could serve as adjunct treatment for diabetes mellitus. The development of a safe, blood glucose lowering and particularly ß-cell protective medication would significantly enhance current diabetes treatment.

Intrahepatic cholestasis of pregnancy (ICP): case report and review of the literature.

Intrahepatic cholestasis of pregnancy (ICP) represents the most common pregnancy-related liver disease in women. Women frequently present in the third trimester with pruritus and elevated serum bile acid and/or alanine transaminase levels. Clinical symptoms quickly resolve after delivery; however, recurrence in subsequent pregnancies has to be expected. Intrahepatic cholestasis of pregnancy is associated with increased perinatal complications, such as premature delivery, meconium staining of the amniotic fluid, respiratory distress, low Apgar scores, and even stillbirth. The risk for the fetus is significantly increased with maternal serum bile acid levels above 40 µmol/L, which characterize severe ICP. An important factor for ICP development is a rise of gestational hormones leading to cholestasis in genetically predisposed women. Variants in the bile salt export pump (BSEP) and the multidrug resistance protein 3 (MDR3) are most often identified in ICP. Here, we give an overview of the current literature on ICP and present the case of a woman with recurrent severe ICP. A common BSEP polymorphism as well as a rare MDR3 mutation may underlie the development of ICP in our patient. She had a premature delivery with meconium staining of the amniotic fluid. The neonate showed signs of respiratory distress with a low Apgar score. This case emphasizes that women with severe ICP have an increased risk for perinatal complications. Furthermore, severe ICP was associated with a MDR3 mutation, which has already been described in adult patients with liver cirrhosis. Thus, ICP may unmask an underlying MDR3 defect, which may predispose to development of hepatobiliary diseases such as gallstone disease, liver fibrosis/cirrhosis, as well as hepatobiliary malignancies. Therefore, genetic testing should be considered in women with severe as well as early onset ICP. Furthermore, regular follow-up should be discussed for women with genetic variants.

Hyperargininemia due to arginase I deficiency: the original patients and their natural history, and a review of the literature.

Hyperargininemia is caused by deficiency of arginase 1, which catalyzes the hydrolysis of L-arginine to urea as the final enzyme in the urea cycle. In contrast to other urea cycle defects, arginase 1 deficiency usually does not cause catastrophic neonatal hyperammonemia but rather presents with progressive neurological symptoms including seizures and spastic paraplegia in the first years of life and hepatic pathology, such as neonatal cholestasis, acute liver failure, or liver fibrosis. Some patients have developed hepatocellular carcinoma. A usually mild or moderate hyperammonemia may occur at any age. The pathogenesis of arginase I deficiency is yet not fully understood. However, the accumulation of L-arginine and the resulting abnormalities in the metabolism of guanidine compounds and nitric oxide have been proposed to play a major pathophysiological role. This article provides an update on the first patients ever described, gives an overview of the distinct clinical characteristics, biochemical as well as genetical background and discusses treatment options.

Fatal non-accidental alpha-lipoic acid intoxication in an adolescent girl.

The aim of our report is to increase awareness that the antioxidant alpha-lipoic acid, which is marketed primarily as weight loss and energy supplement, has potentially lethal effects. A 14-year-old girl ingested in suicidal intention a large amount of alpha-lipoic acid, which led to multiorgan failure and subsequent death within 24 h. Multiorgan failure consisted of decreased myocardial contractility, seizures, anuria, thrombocytopenia, and coagulopathy. Therapy consisted of ventilation, anticonvulsive treatment and circulatory support with high-dose catecholamines. According to alpha-lipoic acid serum levels following ingestion the girl must have ingested a minimum of 10 alpha-lipoic acid tablets of 600 mg each. This is the first report on a fatal case of alpha-lipoic acid ingestion, which is intended to inform physicians, pharmacists and patients about critical side effects of this allegedly innocuous drug.

Nasogastric vs. intravenous rehydration in children with gastroenteritis and refusal to drink: a randomized controlled trial.

BACKGROUND: Nasogastric rehydration therapy (NGRT) is the recommended therapy in moderately dehydrated children with gastroenteritis and refusal to drink, since it is supposed to be as effective if not better than intravenous rehydration therapy (IVRT). However, in clinical practice IVRT is often favored. We conducted a clinical trial to determine whether IVRT is not inferior to NGRT. PATIENTS AND METHODS: Children 3 months to 6 years of age with moderate dehydration and refusal to drink secondary to gastroenteritis were recruited. After clinical assessment of the degree of dehydration, patients were assigned randomly to receive either IVRT or NGRT over 6 h on the hospital ward. RESULTS: Recruitment did not yield the estimated number of patients. Mainly, non-enrollment was due to failure to obtain parental consent because IVRT was expected. 97 patients were enrolled in the study, 46 were randomized to NGRT and 51 to IVRT. There was no difference between IVRT and NGRT groups concerning length of hospital stay (2.2±1.1 days vs. 2.4±1.1 days), success of rehydration (78 vs. 76%) and adverse events. DISCUSSION: Since we had to terminate the study ahead of schedule due to a low recruiting rate, our results are not reliable. However, data from the literature shows that the widespread described superiority of NGRT over IVRT is seriously influenced by studies from developing countries questioning the applicability of the results to a setting available in high-income countries nowadays. CONCLUSION: Our study demonstrates the difficulties performing such a study in a high-income country to come to an objective and clearly evident final conclusion.

Association of exercise-induced hyperinsulinaemic hypoglycaemia with MCT1-expressing insulinoma.

AIMS/HYPOTHESIS: Exercise-induced hyperinsulinism (EIHI) is a hypoglycaemic disorder characterised by inappropriate insulin secretion following anaerobic exercise or pyruvate load. Activating promoter mutations in the MCT1 gene (also known as SCLA16A1), coding for monocarboxylate transporter 1 (MCT1), were shown to associate with EIHI. Recently, transgenic Mct1 expression in pancreatic beta cells was shown to introduce EIHI symptoms in mice. To date, MCT1 has not been demonstrated in insulin-producing cells from an EIHI patient. METHODS: In vivo insulin secretion was studied during an exercise test before and after the resection of an insulinoma. The presence of MCT1 was analysed using immunohistochemistry followed by laser scanning microscopy, western blot analysis and real-time RT-PCR of MCT1. The presence of MCT1 protein was analysed in four additional insulinoma patients. RESULTS: Clinical testing revealed massive insulin secretion induced by anaerobic exercise preoperatively, but not postoperatively. MCT1 protein was not detected in the patient's normal islets. In contrast, immunoreactivity was clearly observed in the insulinoma tissue. Western blot analysis and real-time RT-PCR showed a four- to fivefold increase in MCT1 in the insulinoma tissue of the EIHI patient compared with human pancreatic islets. MCT1 protein was detected in three of four additional insulinomas. CONCLUSIONS/INTERPRETATION: We show for the first time that an MCT1-expressing insulinoma was associated with EIHI and that MCT1 might be present in most insulinomas. Our data suggest that MCT1 expression in human insulin-producing cells can lead to EIHI and warrant further studies on the role of MCT1 in human insulinoma patients.

Neuromyelitis optica and pregnancy during therapeutic B cell depletion: infant exposure to anti-AQP4 antibody and prevention of rebound relapses with low-dose rituximab postpartum.

Neuromyelitis optica (NMO) predominantly affects women, some in childbearing age, and requires early therapeutic intervention to prevent disabling relapses. We report an anti-AQP4 antibody-seropositive patient who became pregnant seven months after low-dose (100 mg) rituximab application. Pregnancy showed no complications, and low-dose rituximab restarted two days after delivery resulted in neurological stability for 24 months. Remarkably, her otherwise healthy newborn presented with anti-AQP4 antibody and reduced B lymphocyte counts in umbilical cord blood, which normalized three months later. Confirming and extending previous reports, our case suggests that low-dose rituximab might be compatible with pregnancy and prevent rebound NMO disease activity postpartum.

Pseudotumor cerebri in childhood and adolescence -- results of a Germany-wide ESPED-survey.

BACKGROUND: No valid epidemiological data on Pseudotumor cerebri (PTC) in childhood and adolescence are available. This national survey aims to raise awareness of the PTC in paediatrics and contribute to a better understanding of age-related characteristics. METHODS: Over 1 year (January-December 2008) new cases of PTC in childhood and adolescence from all paediatric hospitals in Germany were collected by the German Paediatric Surveillance Unit for rare diseases (ESPED). RESULTS: With a total of 61 cases, an annual incidence of 0.5 per 100 000 children <18 years was found. Children of all age groups were affected. A female preponderance and obesity was only found in adolescents. Clinical presentation was variable. Headaches represent the most common symptom affecting prepubertal children less frequently. A wide range of vision problems could be documented (papilledema, visual loss, double vision, visual field defects, disturbed colour and stereo vision). In 10 patients no papilledema was found. Comorbidities were reported in 23% of patients. 14 children gained remission after lumbar puncture without medication. Acetazolamide was the drug of choice, with relatively low dosages used. Escalation strategies were variable. 2 patients were treated invasively (sinus venous stent, LP shunt). CONCLUSION: PTC in childhood and adolescence appears to be as frequent as in the general population. Unspecific clinical characteristics and the broad spectrum of ophthalmologic findings emphasize the importance of a skilful neuroophthalmological investigation. Inconsistent therapeutic approaches are most likely due to a lack of diagnostic and therapeutic standards. Present diagnostic criteria and guidelines for the management of paediatric PTC do not sufficiently consider paediatric aspects.

Sedation of children during measurement of CSF opening pressure: lack of standardisation in German children with pseudotumor cerebri.

BACKGROUND: Diagnosis of pseudotumor cerebri (PTC) requires proper documentation of raised CSF opening-pressure. In childhood results may not be reliable due to insufficient sedation/analgesia or drug effects. We aimed to evaluate the current practice regarding pain and stress management in children undergoing lumbar puncture (LP) for pressure measurement. METHODS: A one-year survey was conducted involving 368 German paediatric departments. All children with newly diagnosed PTC should be reported. Details analyzed here included: age, sex, CSF opening pressure and type of procedural sedation and analgesia (PSA) during LP. RESULTS: 61 patients were analyzed, aged 6 months to 17 years. 29 patients (47%) did not receive any kind of PSA. In children receiving PSA the following regimens were used: Ketamine; Midazolam; Ketamine + Midazolam; Midazolam + Piritramide; Propofol; Profofol + Midazolam; general anaesthesia. CONCLUSION: Pain and stress management in children undergoing LP for CSF opening pressure measurement is often insufficient. Pain, stress and the variability of PSA regimen may be confounders of pressure measurement. In order to prevent false diagnoses of PTC and to obtain comparable results at different centers, a general consensus on PSA in children undergoing LP for CSF opening pressure measurements is required.

Bloody nipple discharge (BND) in an 8 months old girl and a 9 months old male--rational diagnostic approach.

Bloody nipple discharge in adults is, in men as well as in women, often a symptom of an underlying malignant disease. In respect of this, multiple invasive and mutilating diagnostic procedures have been performed in infants and older children. Apart from individual cases in older and pubertal children, in childhood benign conditions are most common and can be diagnosed by non-invasive diagnostic procedures. Here we discuss a rational diagnostic approach on the basis of 2 patients with bloody nipple discharge at the age of 8 and 9 months which resolved spontaneously without treatment after 3 and 6 months, respectively.

Cat scratch disease--heterogeneous in clinical presentation: five unusual cases of an infection caused by Bartonella henselae.

BACKGROUND: Cat-scratch disease (CSD) is common in children, however the wide spectrum of the clinical presentation of CSD may lead to delayed diagnosis. An atypical presentation of CSD includes in its differential diagnosis diseases such as tuberculosis, other mycobacterioses, Epstein-Barr-Virus infection (EBV) or malignant disease. Since, in a small number of cases, these diseases may be present concurrently with an active CSD, it is important to consider CSD early in the differential diagnosis and order the appropriate tests. These tests include serology and, where possible, histology including molecular diagnostic methods on tissue specimens. PATIENTS AND METHOD: We performed a case series of five patients treated in our hospital with a clinical diagnosis of cat-scratch disease, confirmed by serology. An analysis of the history and clinical symptoms associated specifically with an atypical presentation of CSD was performed. RESULTS: The clinical presentation of CSD no longer encompasses the original typical description from 1950, but rather presents with a wide spectrum of signs and symptoms, including the absence of a documented cat scratch, fever, primary lesions or peripheral lymphadenopathy. Low density lesions in spleen, liver and lymph nodes are typical findings in ultrasound, MRI, or CT. Ignoring CSD as a possibility in investigating possible malignancy or tuberculosis could lead to unnecessary hospitalisation and delay in the proper treatment. CONCLUSION: CSD should also be considered in differential diagnosis of any patient with intraabdominal lymphadenopathy, abdominal pain and fever of unknown origin. A careful history is important, however, often patients with CSD have no history of contact with cats. Therefore in atypical cases of CSD the finding of other clinical symptoms and performance of specific diagnostic tests is important. Our experience suggests that early serological testing for Bartonella henselae should be performed and may avoid invasive diagnostic procedures.

Diagnostic difficulties in glucokinase hyperinsulinism.

Glucokinase hyperinsulinism is a rare variant of congenital hyperinsulinism caused by activating mutations in the glucokinase gene and has been reported so far to be a result of overactivity of glucokinase within the pancreatic beta-cell. Here we report on a new patient with difficulties to diagnose persistent hyperinsulinism and discuss diagnostic procedures of this as well as the other reported individuals. After neonatal hypoglycemia, the patient was reevaluated at the age of 3 years for developmental delay. Morning glucose after overnight fast was 2.5-3.6 mmol/l. Fasting tests revealed supressed insulin secretion at the end of fasting (1.4-14.5 pmol/l). In addition, diagnostic data of the patients reported so far were reviewed. A novel heterozygous missense mutation in exon 10 c.1354G>C (p.Val452Leu) was found and functional studies confirmed the activating mutation. There was no single consistent diagnostic criterion found for our patient and glucokinase hyperinsulinism individuals in general. Often at the time of hypoglycemia low insulin levels were found. Therefore insulin concentrations at hypoglycemia, or during fasting test as well as reactive hypoglycemia after an oral glucose tolerance test were not conclusive for all patients. A glucose lowering effect in extra-pancreatic tissues independent from hyperinsulinism that results in diagnostic difficulties may contribute to underestimation of glucokinase hyperinsulinism. Mutational analysis of the GCK-gene should be performed in all individuals with unclear episodes of hypoglycemia even without documented hyperinsulinism during hypoglycemia. Delay of diagnosis might result in mental handicap of the affected individuals.

Diagnosis of glutathione synthetase deficiency in newborn screening.

Glutathione synthetase (GSS) deficiency is a rare disorder of glutathione metabolism with varying clinical severity. Patients may present with haemolytic anaemia alone or together with acidosis and central nervous system impairment. Diagnosis is made by clinical presentation and detection of elevated concentrations of 5-oxoproline in urine and low GSS activity in erythrocytes or cultured skin fibroblasts. Diagnosis can be confirmed by mutational analysis. Treatment consists of the correction of acidosis, blood transfusion, and supplementation with antioxidants. The most important determinants for outcome and survival in patients with GSS deficiency are early diagnosis and early initiation of treatment. The case of a newborn with GSS deficiency diagnosed by tandem mass spectrometry (MS/MS)-based newborn screening is described. After onset of clinical symptoms on the 2nd day of life, expanded newborn screening revealed normal results for all disorders included in the German screening programme; however, selective MS/MS screening revealed a >10-fold elevation of 5-oxoproline in dried blood, leading to the presumptive diagnosis of GSS deficiency by the 5th day of life. Diagnosis was later confirmed by detection of markedly reduced glutathione concentration in erythrocytes and mutational analysis of the GSS gene. Presently, GSS deficiency is not included in newborn screening programmes in Europe. As outcome depends significantly on early start of treatment, routine inclusion of this disorder in newborn screening panels should be considered.

Management and outcome in 75 individuals with long-chain fatty acid oxidation defects: results from a workshop.

At present, long-chain fatty acid oxidation (FAO) defects are diagnosed in a number of countries by newborn screening using tandem mass spectrometry. In the majority of cases, affected newborns are asymptomatic at time of diagnosis and acute clinical presentations can be avoided by early preventive measures. Because evidence-based studies on management of long-chain FAO defects are lacking, we carried out a retrospective analysis of 75 patients from 18 metabolic centres in Germany, Switzerland, Austria and the Netherlands with special regard to treatment and disease outcome. Dietary treatment is effective in many patients and can prevent acute metabolic derangements and prevent or reverse severe long-term complications such as cardiomyopathy. However, 38% of patients with very long-chain acyl-CoA dehydrogenase (VLCAD) deficiency had intermittent muscle weakness and pain despite adhering to therapy. Seventy-six per cent of patients with disorders of the mitochondrial trifunctional protein (TFP)-complex including long-chain 3-hydroxyacyl-CoA dehydrogenase (LCHAD) deficiency, had long-term myopathic symptoms. Of these, 21% had irreversible peripheral neuropathy and 43% had retinopathy. The main principle of treatment was a fat-reduced and fat-modified diet. Fat restriction differed among patients with different enzyme defects and was strictest in disorders of the TFP-complex. Patients with a medium-chain fat-based diet received supplementation of essential long-chain fatty acids. l-Carnitine was supplemented in about half of the patients, but in none of the patients with VLCAD deficiency identified by newborn screening. In summary, in this cohort the treatment regimen was adapted to the severity of the underlying enzyme defect and thus differed among the group of long-chain FAO defects.

Treatment recommendations in long-chain fatty acid oxidation defects: consensus from a workshop.

Published data on treatment of fatty acid oxidation defects are scarce. Treatment recommendations have been developed on the basis of observations in 75 patients with long-chain fatty acid oxidation defects from 18 metabolic centres in Central Europe. Recommendations are based on expert practice and are suggested to be the basis for further multicentre prospective studies and the development of approved treatment guidelines. Considering that disease complications and prognosis differ between different disorders of long-chain fatty acid oxidation and also depend on the severity of the underlying enzyme deficiency, treatment recommendations have to be disease-specific and depend on individual disease severity. Disorders of the mitochondrial trifunctional protein are associated with the most severe clinical picture and require a strict fat-reduced and fat-modified (medium-chain triglyceride-supplemented) diet. Many patients still suffer acute life-threatening events or long-term neuropathic symptoms despite adequate treatment, and newborn screening has not significantly changed the prognosis for these severe phenotypes. Very long-chain acyl-CoA dehydrogenase deficiency recognized in neonatal screening, in contrast, frequently has a less severe disease course and dietary restrictions in many patients may be loosened. On the basis of the collected data, recommendations are given with regard to the fat and carbohydrate content of the diet, the maximal length of fasting periods and the use of l-carnitine in long-chain fatty acid oxidation defects.

Infantile onset neurofibromatosis type 2 presenting with peripheral facial palsy, skin patches, retinal hamartoma and foot drop.

BACKGROUND: Neurofibromatosis type 2 (NF2) has long been regarded as an adult onset disease. However, it is now known that many NF2 patients present clinical signs and symptoms in early childhood. We here report an illustrative case of a male adolescent with an infantile onset clinical symptomatology. PATIENT: A 15-year-old male adolescent presented with a history of congenital peripheral facial palsy, amblyopia, a retinal "membrane", and weakness of the left lower limb. Clinical, electrophysiological, radiological, and molecular studies of the patient are shown. A peripheral axonal neuropathy of the left lower limb was found. Formerly unidentified retinal findings could be diagnosed as combined pigment epithelial, and retinal hamartoma (CPERH). In addition, two café au lait spots and a nodular skin tumour were found. Bilateral vestibular schwannoma finally led to the diagnosis of NF2, which could be genetically confirmed. CONCLUSIONS: NF2 can already become evident in infancy. While in adulthood tinnitus, hearing loss and vestibular symptoms are the classical signs, these are often absent in the paediatric group. Children rather have ocular symptoms, neurological problems such as cranial nerve palsies other than eighth nerve, limb weakness and skin manifestations as early clinical signs.

Neurological findings in Hunter disease: pathology and possible therapeutic effects reviewed.

Hunter disease (mucopolysaccharidosis type II, MPS II) is an X-linked lysosomal storage disease caused by deficiency of iduronate-2-sulfatase. Accumulation of chondroitin sulfate B and heparan sulfate in various tissues is the biochemical consequence of MPS II. Children with Hunter disease are normal at birth, and symptoms occur between 2 and 10 years of age. Typical symptoms include coarse facies with enlarged tongue and prominent forehead as well as a short, stocky built stature with short neck. The cardiovascular, respiratory and gastrointestinal systems may be affected, and oral, dermatological and psychiatric as well as neurological complications are described. Life expectancy is markedly reduced and may be limited to 12 years for severely affected patients. The most common causes of death are airway obstruction and cardiac failure. The most severe symptoms may result from neurological symptoms or complications including hydrocephalus, spinal cord compression, cervical myelopathy, optic nerve compression, and hearing impairment. Patients may also develop carpal tunnel syndrome, sleep apnoea, seizures or mental retardation. This review describes characteristic neurological manifestations in MPS II and its underlying pathophysiology. In addition, an appraisal is given whether or not enzyme replacement therapy may be able to improve in particular the neurological symptoms of Hunter disease.