Experience in a PHTS Expertise Centre: Yield of Thyroid Ultrasound Surveillance in Children with PTEN Hamartoma Tumor Syndrome.

Objective: Children with PTEN hamartoma tumor syndrome (PHTS) are at increased risk for developing thyroid abnormalities, including differentiated thyroid carcinoma (DTC). The Dutch PHTS guideline recommends ultrasound surveillance starting from age 18. Since the literature describes PHTS patients who developed DTC before age 18, the Dutch PHTS expertise centre has initiated annual ultrasound surveillance starting from age 12. The purpose of this study was to identify the yield of thyroid ultrasound surveillance in children. Methods: A retrospective single centre cohort study was conducted. Pediatric PHTS patients who received thyroid ultrasound surveillance before age 18 between 2016-2023 were included. Patients' medical records have been reviewed. Primary outcomes included prevalence and time to develop thyroid nodules ≥10mm, nodular growth, goiter, thyroiditis and DTC. Descriptive statistics and Kaplan-Meier analyses were performed. Results: Forty-three patients were included. Two patients (5%) were diagnosed with DTC at ages 12 and 17. Both DTCs were identified as minimally invasive follicular carcinoma at stages pT3NxMx and pT1NxMx respectively. A total of 84% were diagnosed with thyroid abnormalities at a median age of 12 years (range 9-18). Most common findings were benign, including nodular disease (74%), goiter (30%) and autoimmune thyroiditis (12%). Nodular growth was observed in 14 patients (33%) resulting in (hemi)thyroidectomy in 7 patients (16%). Conclusion: Thyroid ultrasound surveillance resulted in the detection of DTC in 2/43 PHTS patients before age 18. These findings support the recommendation to initiate thyroid ultrasound surveillance in children at least from age 12, preferably within an expertise centre.

IGF1 Haploinsufficiency: Phenotype and Response to Growth Hormone Treatment in 9 Patients.

INTRODUCTION: The clinical features of bi-allelic IGF1 defects are well established, i.e., severe growth failure and microcephaly, delayed psychomotor development, and sensorineural deafness. However, information on clinical and endocrine consequences of heterozygous IGF1 variants and treatment options is scarce. We aimed at extending the knowledge base of the clinical presentation and growth response to recombinant human growth hormone (rhGH) of patients carrying such variants. METHODS: Retrospective case series of patients with pathogenic heterozygous IGF1 variants. RESULTS: Nine patients from six families were included, harbouring five whole or partial gene deletions and one frameshift variant resulting in a premature stop codon (three de novo, one unknown inheritance). In the other two families, variants segregated with short stature. Mean (SD) birth length was -1.9 (1.3) SDS (n = 7), height -3.8 (0.6) SDS, head circumference -2.5 (0.6) SDS, serum IGF-I -1.9 (0.7) SDS, serum IGFBP-3 1.1 (0.4) SDS (n = 7), and GH peak range 5-31 µg/L (n = 4). Five patients showed feeding problems in infancy. Average height increased after 1 and 2 years of rhGH treatment by 0.8 SDS (range 0.3-1.3 SDS) and 1.3 SDS (range 0.5-2.0 SDS), respectively. Adult height in 2 patients was -2.8 and -1.3 SDS, which was, respectively, 1.3 and 2.9 SDS taller than predicted before start of treatment. CONCLUSION: Haploinsufficiency of IGF1 causes a variable phenotype of prenatal and postnatal growth failure, microcephaly, feeding difficulties, low/low-normal serum IGF-I values in contrast to serum IGFBP-3 in the upper-normal range. Treatment with rhGH increased growth in the first 2 years of treatment, and in 2 patients adult height after treatment was higher than predicted at treatment initiation.

Facilitators and barriers to the transition from outpatient clinic visits to home-based check-ups for children being treated with growth hormone: a mixed-methods study.

Although the coronavirus disease 2019 (COVID-19) pandemic accelerated the adoption and expansion of telemedicine worldwide, little is known about the transition to home-based care for children. This study aims to investigate the facilitators and barriers to the transition from outpatient clinic visits to home-based check-ups (HBCU), for children being treated with growth hormone. A mixed-methods study was performed at Amalia Children's Hospital (Radboud University Medical Centre, Nijmegen), consisting of questionnaires and semi-structured and focus group interviews. For the quantitative part, the Measurement Instrument for Determinants of Innovation (MIDI) was utilised to investigate the facilitators and barriers for the 81 participants regarding the transition to HBCU. The MIDI questionnaire is comprised of four domains: the innovation-, user-, organisation-, and the socio-political scale. Descriptive statistics were performed for analysing the questionnaires. For the qualitative part, interviews with 10 participants derived from the questionnaire and the two focus group interviews were conducted, to gain more in-depth information about the research topic, until data saturation was reached. The interviews were analysed by using the reflective thematic approach, starting with deductive coding and followed by inductive coding. Several facilitators were recognised in our study: procedural clarity, self-efficacy, convenience, patient-centred care, increased accuracy in height measurements, social support, client/patient satisfaction/cooperation, patient-centred care, the flexibility and adaptivity of HBCU, physical start-up period of HBCU, and a potential decrease in healthcare costs. However, several barriers were also noted in our study: poor compatibility with current practice, lack of consultation within the team, feeling of being less controlled by physicians, unsettledness of the organisation, an increased workload for the staff, and insufficient information communication technology (ICT) facilities. CONCLUSION: This study revealed that HBCU have considerable benefits for both patients and healthcare professionals, from the standpoint of innovation, user, and socio-political points of view. The identified facilitators and barriers to HBCU should be taken into account when further steps of implementing HBCU are considered. WHAT IS KNOWN: • The Corona-Virus-Disease 2019 (COVID-19) pandemic has had an immense impact on health care worldwide. A substantial amount of the outpatient clinic visits for children treated with growth hormone was, as a result of the pandemic, transferred to online consultation. Transitioning paediatric growth hormone treatment to the home setting may be favorable for children and their parents/caregivers) as well for healthcare professionals. • Insights regarding facilitators and barriers is vital for the successful implementation and adoption of home-care technologies. WHAT IS NEW: • To our knowledge, we are first to report on and explicit the facilitators and barriers of the transition to home-based check-ups, via online consultation for children being treated with growth hormone. • Both children and healthcare professionals reported major facilitators and some minor barriers to the transition to home-based check-ups, illustrating their potential value. These facilitators and barriers should be considered while working towards implementation of home-based check-ups.

Parental measurement of height in growth hormone-treated children in the hospital setting proves valid: an observational study - potential for replacement of outpatient clinic visits to the home setting.

Reliable height measurement plays a pivotal role in evaluating the efficacy of costly growth hormone (GH) therapy in children. Currently, regularly outpatient clinic visits are needed to accurately measure height. The outpatient clinic visits are time-consuming for parents as well for health care professionals. This observational study aimed to investigate the validity of parentally performed height measurements compared to height measurements in the outpatient setting. An observational study was performed at the outpatient clinic of Amalia's Children's Hospital Nijmegen. A portable stadiometer (PS) was developed for height measurements at home. Measurements with the PS were performed by the researcher (PSR) and parents/caregivers (PSP). Measurements performed with the electronic digital ruler (EDS) were considered as the gold standard. The parents were potentially unblinded for the gold standard measurement (EDS). Descriptive statistics, Wilcoxon signed-rank, and Pearson's correlation tests were performed. The Bland-Altman plots were made to illustrate the correlation of the PSR or PSP with the gold standard. The correlation between the height measurements with PSR or PSP compared to the EDS was substantial (PSR: r = 0.9998, R2 = 0.9996, P < 0.001; PSP: r = 0.9998, R2 = 0.9995, P < 0.001). However, a statistically significant underestimation of the PSR and PSP was observed (P < 0.001). The mean difference of the PSR and PSP was respectively - 0.21 cm ± 0.52 SD and - 0.30 cm ± 0.62 SD in comparison to the EDS. The Bland-Altman plots illustrated that 95% of the PSR measurements were between - 1.03 and 0.60 cm and 95% of the PSP measurements were between - 1.26 and 0.66 cm compared to the EDS. CONCLUSION: We found a strong correlation between the PSR or PSP and the EDS, with only a minor underestimation of approximately 0.2-0.3 cm. In our opinion, this underestimation is clinically irrelevant as it does not result in an adjustment in GH dose. To conclude, parental height measurements could be a promising tool as it partially replaces outpatient clinic visits needed for measurements of height. Further studies are required to confirm this statement. WHAT IS KNOWN: • The immense impact of the coronavirus disease 2019 (COVID-19) pandemic on health care has increased telemedicine worldwide. For adequate integration of telemedicine in paediatric growth hormone treatment, reliable height and weight measurements in the home setting are required. • Earlier studies have shown that parents are capable to reliable perform height measurements in healthy children. WHAT IS NEW: • To our knowledge, this is the first study to show a strong correlation between the height measurements with a portable stadiometer by parents and those made with the electronic digital ruler (gold standard) in children treated with growth hormone. There was only a minor underestimation of approximately 0.2-0.3 cm, which we anticipated to be clinically irrelevant. • Therefore, home height measurements can at least partly replace costly outpatient visits for children being treated with growth hormone as part of an uncomplicated course. Moreover, these results may also be promising for implementation in other paediatric populations besides children treated with growth hormone.

The Indirect Basophil Activation Test Is a Safe, Reliable, and Accessible Tool to Diagnose a Peanut Allergy in Children.

BACKGROUND: The gold standard for the diagnosis of a peanut allergy is an oral food challenge (OFC), but it is a time-consuming, patient-unfriendly, and expensive test. The in vitro direct basophil activation test (BAT) for peanuts was shown to be a promising diagnostic tool for replacing the OFC. OBJECTIVE: To determine the diagnostic accuracy of the indirect (passive) BAT. Compared with the direct BAT, the timing of the indirect BAT is more flexible, and the problem of nonresponding basophils (unresponsive to IgE receptor-mediated signaling) is circumvented. METHODS: In 74 children, suspected of peanut allergy and eligible for an OFC, indirect BAT results for peanut extract, Ara h2, and Ara h6 were compared with the results of a double-blind placebo-controlled food challenge. The reactivity and sensitivity of the basophils in the BAT were correlated to both the allergy status and the threshold dose in the OFC. RESULTS: The combined basophil reactivity for Ara h2 and Ara h6 showed the highest accuracy (94%) for the diagnosis of a peanut allergy, with positive and negative predictive values of 96% and 89%, respectively. The sensitivity of the basophils for Ara h2 significantly discriminates between patients who tolerated up to 0.4 g of peanut protein in the OFC and those who did not. CONCLUSIONS: Because the indirect BAT showed a high diagnostic accuracy for peanut allergy, it is a promising alternative to the classical direct BAT and could lead to a reduction in OFC use.

Two-year effects of the community-based overweight and obesity intervention program Gezond Onderweg! (GO!) in children and adolescents living in a low socioeconomic status and multi-ethnic district on Body Mass Index-Standard Deviation Score and quality of life.

BACKGROUND: In most childhood obesity interventions, disadvantaged groups are underrepresented, and results are modest and not maintained. A long-term collaborative community-based approach is necessary to reach out to children from multi-ethnic backgrounds and achieve sustainable behavior change, resulting in sustained Body Mass Index-Standard Deviation Score (BMI-SDS) reductions. The objective is to determine the effects of GO! on BMI-SDS and Health-Related Quality of Life (HRQoL) for children and adolescents having overweight or obesity. METHODS: A prospective, longitudinal cohort study was used to collect two-year follow-up data from November 2014 to July 2019. Children and adolescents (4-19 years old) from the low socioeconomic status and multi-ethnic district of Malburgen in the Dutch city of Arnhem were included. 178 children having overweight or obesity were recruited, with 155 children measured at baseline and after two years as a minimum, while 23 were lost to follow up. Participants attending the program for over six months were defined as completers (n=107) and participants attending the program for less than six months were defined as non-completers (n=48). The child health coach (CHC) acts as a central care provider in the collaborative community with healthcare providers from both medical and social fields. This coach coordinates, monitors and coaches healthy lifestyles, while increasing self-management for both children and parents. This is done in a customized and neighborhood-oriented manner and provided by all the stakeholders involved in GO!. The main outcomes are the change in BMI-SDS scores and HRQoL scores reported by participants. FINDINGS: After 24 months, completers showed a decrease in BMI-SDS of -0·32 [95% CI: -0·42, -0·21], compared with -0·14 [95% CI: -0·29, 0·01] for non-completers (adjusted for gender and ethnicity; P=0.036). While 25% suffered from overweight and 75% from obesity at the start, following the intervention 5% showed normal weight, with 33% overweight and 62% with obesity. HRQoL reported by participants improved over time, showing no differences between completers and non-completers, gender and ethnicity after two years. INTERPRETATION: Our results suggest that the GO! program might be effective in reaching out and reducing BMI-SDS for participants in a low socioeconomic status and multi-ethnic district over a two-year period. We noticed also trends to beneficial shifts in obesity grades. HRQoL improved regardless of the participation rate, gender and ethnic background. In light of the study limitations, further studies are needed to corroborate our observations. FUNDING: Dullerts-foundation, Nicolai Broederschap foundation, Burger en Nieuwe weeshuis foundation, Rijnkind foundation, Arnhems Achterstandswijken foundation, Menzis-foundation, the municipalities of Arnhem, Rheden, Overbetuwe and Lingewaard, the Association of Dutch municipalities, and Province of Gelderland.

Cell Biological Responses after Shiga Toxin-1 Exposure to Primary Human Glomerular Microvascular Endothelial Cells from Pediatric and Adult Origin.

Hemolytic uremic syndrome (HUS) is characterized by a triad of symptoms consisting of hemolytic anemia, thrombocytopenia and acute renal failure. The most common form of HUS is caused by an infection with Shiga toxin (Stx) producing Escherichia coli bacteria (STEC-HUS), and the kidneys are the major organs affected. The development of HUS after an infection with Stx occurs most frequently in children under the age of 5 years. However, the cause for the higher incidence of STEC-HUS in children compared to adults is still not well understood. Human glomerular microvascular endothelial cells (HGMVECs) isolated and cultured from pediatric and adult kidney tissue were investigated with respect to Stx binding and different cellular responses. Shiga toxin-1 (Stx-1) inhibited protein synthesis in both pediatric and adult HGMVECs in a dose-dependent manner at basal conditions. The preincubation of pediatric and adult HGMVECs for 24 hrs with TNFα resulted in increased Stx binding to the cell surface and a 20-40% increase in protein synthesis inhibition in both age groups. A decreased proliferation of cells was found when a bromodeoxyuridine (BrdU) assay was performed. A trend towards a delay in endothelial wound closure was visible when pediatric and adult HGMVECs were incubated with Stx-1. Although minor differences between pediatric HGMVECs and adult HGMVECs were found in the assays applied in this study, no significant differences were observed. In conclusion, we have demonstrated that in vitro primary HGMVECs isolated from pediatric and adult kidneys do not significantly differ in their cell biological responses to Stx-1.

Raising the Cut-Off Level of Anti-Tissue Transglutaminase Antibodies to Detect Celiac Disease Reduces the Number of Small Bowel Biopsies in Children with Type 1 Diabetes: A Retrospective Study.

OBJECTIVE: To study the optimal cut-off value for anti-tissue transglutaminase type 2 IgA antibodies (TG2A) in serum to select for diagnostic small bowel biopsies for celiac disease in children with type 1 diabetes mellitus. STUDY DESIGN: Children with type 1 diabetes mellitus with elevated TG2A titers and duodenal biopsies performed during the course of their diabetes treatment were included. Anti-endomysial antibodies were recorded if present. The optimal TG2A cut-off value, expressed as the ratio between obtained value and upper limit of normal (ULN), was determined using receiver operating characteristic curve analysis and compared with the cut-off value used in the European Society for Pediatric Gastroenterology, Hepatology and Nutrition guidelines in terms of sensitivity, specificity, positive and negative predictive value. RESULTS: We included 63 children. The optimal cut-off value for performing biopsies is demonstrated to be 11 times the ULN. Raising the cut-off value from 3 times the ULN to 11 times the ULN changed sensitivity from 96% to 87% and increased specificity from 36% to 73%, increased the positive predictive value from 88% to 94% and lowered negative predictive value from 67% to 53%. The percentage of normal histology was decreased from 12% to 6%. CONCLUSIONS: Increasing the TG2A cut-off value for performing duodenal biopsies in children with type 1 diabetes mellitus and suspected celiac disease leads to a substantial reduction of unnecessary biopsies. We advocate to adapt the European Society for Pediatric Gastroenterology, Hepatology and Nutrition 2012 guidelines for this group of children, including monitoring patients with TG2A levels of less than 11 times the ULN over time.

Corrigendum to "Benign course after acute high dose levothyroxine intoxication in a 3-year-old boy".

[This corrects the article DOI: 10.1297/cpe.26.171.].

[New test to detect food allergy: the basophil activation test]. / Basofielenactivatietest bij IgE-gemedieerde voedselallergie.

Over recent decades the prevalence of food allergies and the allergy-related costs of care have increased considerably. The double-blind, placebo-controlled food challenge test is the gold standard for diagnosing food allergy. However, this test is not without risk and it is labour-intensive and expensive. In addition, the food challenge test only has limited availability which has led to (long) waiting lists. Therefore, there is a need for a safe, reliable and patient-friendly test to detect food allergy that is also fast and cheap. The basophil activation test is a potentially good alternative, however, it is only available at a few clinics and laboratories in the Netherlands and it can currently only be used for a limited number of allergens - and therefore only in a limited number of patients. National collaboration between laboratories and allergy centres should lead to more knowledge, the consolidation of which will benefit the validation and national implementation of the test.

The Basophil Activation Test reduces the need for a food challenge test in children suspected of IgE-mediated cow's milk allergy.

BACKGROUND: The gold standard for the diagnosis of cow's milk allergy is the Double-Blind Placebo-Controlled Food Challenge (DBPCFC) test. However, disadvantages of the DBPCFC are the potential risk of anaphylactic reactions, the time-consuming procedure and high costs. OBJECTIVE: The aim of this study was to determine the reliability of the Basophil Activation Test (BAT) both for the initial diagnosis of cow's milk allergy in children and for the determination of tolerance in children with cow's milk allergy. METHODS: Ninety-seven BATs and cow's milk-specific IgE (sIgE) tests were performed in 86 infants/young children, suspected of (persistent) cow's milk allergy, who were qualified for an in-hospital DBPCFC. The BAT was performed with cow's milk extract and the purified major allergens casein, α-lactalbumin, ß-lactoglubulin. Basophil activation was determined by CD63 upregulation measured by flow cytometry. The BAT results were compared to the DBPCFC outcomes. RESULTS: Based on unequivocal DBPCFC and BAT result combinations (80%), the BAT had a sensitivity and specificity of 100% (CI: 86%-100% and 68%-100%, respectively) in IgE-sensitized children (41% of the tested children). All non-IgE-sensitized children (59%) had a negative DBPCFC and BAT, except for five patients. These latter showed delayed and relatively mild symptoms in the DBPCFC with a negative BAT, supporting a non-IgE-mediated allergy in these children. CONCLUSIONS AND CLINICAL RELEVANCE: The BAT seems reliable and cost-effective to diagnose patients with an IgE-mediated cow's milk allergy. In IgE-sensitized patients, a BAT might replace a DBPCFC. For non-IgE-sensitized patients presenting with mild symptoms, we propose to consider a (double-blind) extended (time) challenge test at home.

Benign course after acute high dose levothyroxine intoxication in a 3-year-old boy.

Acute ingestion of thyroid hormone preparations is a common intoxication, with 181 cases in children <12 yr in 2009 in the Netherlands, but generally has a mild course. However, some reports show that even low dosages may cause serious events such as seizures, thyroid storm and coma. We report a 3 yr old boy case with an acute intoxication with high dose levothyroxine (0.5 mg/kg). We describe the proper management of levothyroxine intoxication in children. A 3-year-old boy with no notable medical history ingested sixty tablets of levothyroxine 150 µg. His vital-signs were normal and the only symptom during admission was a tachycardia the following day. Laboratory data showed elevated T3, fT3 and fT4 levels; and decrease TSH levels. He was treated prophylactically and therapeutically with activated charcoal and propranolol. Despite very high levels, his clinical symptoms were relatively mild. After clinical follow-up for 3 d he was discharged. We propose that children with thyroid hormone intoxication with either a levothyroxine dose >0.1 g/kg, a short interval since ingestion, symptomatic presentation, and/or a fT4 >100 pmol/l should be monitored in the hospital during at least 48-72 h post-ingestion and on an outpatient basis for 14 d.

Frequent delay of coeliac disease diagnosis in symptomatic patients with type 1 diabetes mellitus: clinical and genetic characteristics.

BACKGROUND: Patients with type 1 diabetes mellitus (T1DM) are more prone to develop other auto-immune diseases, including coeliac disease (CD). Paediatric patients with T1DM are screened for CD, whereas in adult T1DM patients screening programs for CD are not standardised. The aim of this study was to investigate clinical and genetic characteristics of patients with both diagnoses so as to lead to better detection of CD in adult patients with T1DM. METHODS: We studied 118 patients with both T1DM and CD identified in The Netherlands. We retrospectively collected data on sex distribution, age of onset of T1DM, age of CD diagnosis, CD complaints, duration of CD complaints before CD diagnosis, family history of CD or T1DM, comorbidity and HLA-DQ type. RESULTS: Thirty-three percent of T1DM+CD patients reported CD related complaints for at least 5 years before CD diagnosis. Two peaks in the age of CD diagnosis in T1DM patients were observed: around 10 and 45 years of age. Women were diagnosed with CD at a younger age than men (median 25 years (IQR 9-38) versus 39 (12-55) years, respectively, P<0.05). CONCLUSION: A delay of CD diagnosis is frequently found in adult T1DM patients and two peaks in the age of CD diagnosis are present in T1DM patients. This observational study emphasises that more frequent screening for CD in particularly adult T1DM patients is required, preferably by a 5 years interval.

Probable association of tachyarrhythmia with nebulized albuterol in a child with previously subclinical wolff Parkinson white syndrome.

We present the case of a 2-year-old asthmatic boy with atrioventricular (AV)-reentry tachycardia following albuterol inhalation, who was later diagnosed with Wolff-Parkinson-White (WPW) syndrome. The Naranjo adverse drug reaction probability scale score for this adverse event was 7, indicating that the association between his AV-reentry tachycardia and inhalation of albuterol is probable. To our knowledge, this is the first case report that shows the potential arrhythmogenic effects of albuterol in a child with WPW syndrome. We urge clinicians to be aware of this potentially life-threatening adverse effect and to closely monitor these patients when they need beta-adrenergic drugs in case of emergency. Furthermore, this report highlights the dilemma regarding the safe treatment of pediatric patients with both asthma and WPW syndrome.

Foreign adopted children are a source of methicillin-resistant Staphylococcus aureus transmission to countries with low prevalence.

We report a 13.0% prevalence rate of methicillin-resistant Staphylococcus aureus (MRSA) carriers in foreign adopted children, who are frequently hospitalized within the first year after arrival. Hospitalization in the country of origin and special need status are no significant risk factors for MRSA colonization. Healthcare workers are overrepresented among their adoptive parents. These children represent a potential source of MRSA transmission into the healthcare system.

Rapid enterovirus molecular testing in cerebrospinal fluid reduces length of hospitalization and duration of antibiotic therapy in children with aseptic meningitis.

We studied the potential benefits of introducing a rapid enterovirus molecular test in children with enterovirus meningitis. The 2 groups of pediatric patients were comparable with respect to clinical and laboratory data, but differed in availability of enterovirus test results. In the control group, the results were available within 3 to 7 days, whereas in the study group, rapid enterovirus molecular test results were available within 3 to 24 hours. The median duration of hospitalization and the duration of antibiotics were significantly reduced to, respectively, 2 days and 1 day in the study group when compared with the control group (P < 0.001). Mean costs per patient calculation showed an average reduction of more than US $1450 (P < 0.001).

Autosomal recessive mental retardation, deafness, ankylosis, and mild hypophosphatemia associated with a novel ANKH mutation in a consanguineous family.

CONTEXT: Mutations in ANKH cause the highly divergent conditions familial chondrocalcinosis and craniometaphyseal dysplasia. The gene product ANK is supposed to regulate tissue mineralization by transporting pyrophosphate to the extracellular space. OBJECTIVE: We evaluated several family members of a large consanguineous family with mental retardation, deafness, and ankylosis. We compared their skeletal, metabolic, and serological parameters to that of the autosomal recessive progressive ankylosis (ank) mouse mutant, caused by a loss-of-function mutation in the murine ortholog Ank. PARTICIPANTS: The studied patients had painful small joint soft-tissue calcifications, progressive spondylarthropathy, osteopenia, mild hypophosphatemia, mixed hearing loss, and mental retardation. RESULTS: After mapping the disease gene to 5p15, we identified the novel homozygous ANK missense mutation L244S in all patients. Although L244 is a highly conserved amino acid, the mutated ANK protein was detected at normal levels at the plasma membrane in primary patient fibroblasts. The phenotype was highly congruent with the autosomal recessive progressive ankylosis (ank) mouse mutant. This indicates a loss-of-function effect of the L244S mutation despite normal ANK protein expression. Interestingly, our analyses revealed that the primary step of joint degeneration is fibrosis and mineralization of articular soft tissues. Moreover, heterozygous carriers of the L244S mutation showed mild osteoarthritis without metabolic alterations, pathological calcifications, or central nervous system involvement. CONCLUSION: Beyond the description of the first human progressive ankylosis phenotype, our results indicate that ANK influences articular soft tissues commonly involved in degenerative joint disorders. Furthermore, this human disorder provides the first direct evidence for a role of ANK in the central nervous system.

Cinacalcet for hyperparathyroidism in pregnancy and puerperium.

The efficacy and safety of various modes of medical treatment for primary hyperparathyroidism (PHPT) in pregnancy is largely unknown. This report describes two cases of PHPT in pregnancy that were temporarily treated with the calcimimetic cinacalcet. The first case was diagnosed in the 31st week of pregnancy. The patient was asymptomatic and had an albumin-corrected total calcium level (Ca(corr)) of 3.24 mmol/l. As serum calcium was only mildly elevated it was decided to postpone surgery to the postpartum period. Cinacalcet was started immediately after delivery to prevent a postpartum surge in serum calcium. The second patient presented with hypertension and symptomatic hypercalcemia (Ca(corr) 3.96 mmol/l) in the 32nd week of pregnancy. Surgery was postponed because of suspected pheochromocytoma. Treatment with a combination of cinacalcet and calcitonin reduced serum Ca(corr) to 3.0 mmol/l. This report describes the monitoring of mother and child, and explores the pros and cons of the use of calcimimetics during pregnancy and puerperium.