Comprehensive dissection of prevalence rates, sex differences, and blood level-dependencies of clozapine-associated adverse drug reactions

Clozapine is often underused due to concerns about adverse drug reactions (ADRs) but studies into their prevalences are inconclusive. We therefore comprehensively examined prevalences of clozapine-associated ADRs in individuals with schizophrenia and demographic and clinical factors associated with their occurrence. Data from a multi-center study (n = 698 participants) were collected. The mean number of ADRs during clozapine treatment was 4.8, with 2.4 % of participants reporting no ADRs. The most common ADRs were hypersalivation (74.6 %), weight gain (69.3 %), and increased sleep necessity (65.9 %), all of which were more common in younger participants. Participants with lower BMI prior to treatment were more likely to experience significant weight gain (>10 %). Constipation occurred more frequently with higher clozapine blood levels and doses. There were no differences in ADR prevalence rates between participants receiving clozapine monotherapy and polytherapy. These findings emphasize the high prevalence of clozapine-associated ADRs and highlight several demographic and clinical factors contributing to their occurrence. By understanding these factors, clinicians can better anticipate and manage clozapine-associated ADRs, leading to improved treatment outcomes and patient well-being.

Barriers and facilitators for healthcare professionals to the implementation of Multidisciplinary Timely Undertaken Advance Care Planning conversations at the outpatient clinic (the MUTUAL intervention): a sequential exploratory mixed-methods study

BACKGROUND

Advance Care Planning (ACP) enables patients to define and discuss their goals and preferences for future medical treatment and care. However, the structural implementation of ACP interventions remains challenging. The Multidisciplinary Timely Undertaken Advance Care Planning (MUTUAL) intervention has recently been developed which takes into account existing barriers and facilitators. We aimed to evaluate the MUTUAL intervention and identify the barriers and facilitators healthcare professionals experience in the implementation of the MUTUAL intervention and also to identify suggestions for improvement.

METHODS

We performed a sequential exploratory mixed-methods study at five outpatient clinics of one, 300-bed, non-academic hospital. Firstly, semi-structured interviews were performed with a purposive sample of healthcare professionals. The content of these interviews was used to specify the Measurement Instrument for Determinants of Innovations (MIDI). The MIDI was sent to all healthcare professionals. The interviews and questionnaires were used to clarify the results.

RESULTS

Eleven healthcare professionals participated in the interviews and 37 responded to the questionnaire. Eight barriers and 20 facilitators were identified. Healthcare professionals agreed that the elements of the MUTUAL intervention are clear, correct, complete, and simple - and the intervention is relevant for patients and their proxies. The main barriers are found within the user and the organisational domain. Barriers related to the organisation include: inadequate replacement of staff, insufficient staff, and insufficient time to introduce and invite patients. Several suggestions for improvement were made.

CONCLUSION

Our results show that healthcare professionals positively evaluate the MUTUAL intervention and are very receptive to implementing the MUTUAL intervention. Taking into account the suggestions for improvement may enhance further implementation.

Prevalence and Predictors of Uncontrolled Asthma in Children Referred for Asthma and Other Atopic Diseases

Background

Uncontrolled asthma in children is still highly prevalent despite the availability of effective asthma treatment. We investigated 1) the prevalence of uncontrolled asthma among children referred for asthma and referred for atopic diseases other than asthma (ie food allergy, allergic rhinitis or atopic dermatitis) to secondary care; and 2) the predictors associated with uncontrolled asthma.

Methods

All children (4 to 18 years) referred for asthma or atopic diseases other than asthma to 8 secondary care centers in The Netherlands were invited to an electronic portal (EP). The EP is a web-based application with several validated questionnaires including the ISAAC questionnaires and the Asthma Control Test (ACT). Children were eligible for inclusion in this study when their parents reported in the EP that their child had asthma diagnosed by a physician. The ACT was used to assess asthma control. Multiple predictors of asthma control (patient, asthma and atopic characteristics) were evaluated by univariable and multivariable logistic regression analyses.

Results

We included 408 children: 259 children (63%) with asthma referred for asthma and 149 children (37%) with asthma referred for atopic diseases other than asthma. Thirty-nine percent of all children had uncontrolled asthma: 47% of the children referred for asthma and 26% of the children referred for atopic diseases other than asthma. Predictors associated with uncontrolled asthma were a family history of asthma (odds ratio [OR] 2.08; 95% confidence interval [95% CI] 1.34 to 3.24), and recurrent upper and lower respiratory tract infections in the past year (OR 2.40; 95% CI 1.52 to 3.81 and OR 2.00; 95% CI 1.25 to 3.23, respectively).

Conclusion

Uncontrolled asthma is highly prevalent in children with asthma referred to secondary care, even if children are primarily referred for atopic diseases other than asthma. Thus, attention should be paid to asthma control in this population.

Predictors of treatment success in children with difficult to treat atopic dermatitis using a personalized integrative multidisciplinary (PIM) treatment programme

BACKGROUND

A 6-week personalized integrative multidisciplinary treatment programme (PIM) was developed for children with difficult to treat AD who appeared unresponsive to treatment according to current guidelines.

OBJECTIVE

The aim of the present study was to identify clinical and psychosocial characteristics that predict long-term treatment success after PIM.

METHODS

Treatment was considered successful when there was a 75% reduction on the Self-Administered Eczema Area and Severity Index and/or little impact of AD on daily life, measured with the Children's Dermatology Life Quality Index (score ≤ 6), 6 months after the end of PIM. PIM is a personalized, integrative, multidisciplinary treatment programme with clearly defined goals and strategies, addressing atopic, paediatric, mental health comorbidities and general well-being, for children and adolescents aged 8- to 18 years. Multivariate logistic regression models were constructed using a backward selection procedure. Questionnaires were used to assess psychosocial characteristics; clinical data was extracted from medical records.

RESULTS

In total, 79 children/adolescents with difficult to treat AD completed PIM and long-term treatment results were available for 74 children/adolescents. The majority (77%) of children/adolescents demonstrated long-term treatment success with PIM. Predictors of long-term treatment success (adjusted ORs) included maternal disease acceptance OR (95% CI) 1.84 (1.15-2.94). A group (23%) of mostly females OR (95% CI) 0.10 (0.02-0.54) with multiple somatic complaints OR (95% CI) 0.88(0.80-0.97), from families where the mother has anxiety for the use of topical corticosteroids OR (95% CI) 0.62(0.40-0.94), is less likely to obtain long-term treatment success.

CONCLUSION

Most children and adolescents with difficult to treat AD, seemingly unresponsive to conventional treatment according to current guidelines, are able to improve with PIM. Psychosocial and family but not clinical variables, predicted long-term treatment success after participating in PIM.

Effectiveness of alpine climate treatment for children with difficult to treat atopic dermatitis: Results of a pragmatic randomized controlled trial (DAVOS trial)

BACKGROUND

Alpine climate treatment has historically been used in Europe to treat atopic dermatitis (AD), but no randomized trials have been conducted to provide evidence for its effectiveness.

OBJECTIVE

To investigate the long-term effectiveness of alpine climate treatment for children with difficult to treat AD.

MATERIALS & METHODS

A pragmatic, open, randomized controlled trial was conducted. Children diagnosed with AD that was considered difficult to treat, aged between 8 and 18 years and willing to be treated in Switzerland were randomized to a six-week personalized integrative multidisciplinary treatment period in a clinical setting in the alpine climate (Switzerland) or an outpatient setting in moderate maritime climate (Netherlands). Study assessments were conducted at the Wilhelmina Children's Hospital; an electronic portal was used for the collection of questionnaire data. Primary outcomes were disease activity (SAEASI), quality of life (CDLQI) and catastrophizing thoughts (JUCKKI/JU) 6 months after intervention. Other assessments were immediately and 6 weeks after intervention. Subgroup analyses concerned asthma-related outcomes. Children were randomly assigned to either the intervention or control group using a covariate adaptive randomization method, taking age and asthma diagnosis into account. Children, parents and healthcare professionals involved in treatment were not blinded to group assignment. Data were analysed according to intention-to-treat with linear mixed-effects models for continuous outcomes. The trial is registered at Current Controlled Trials ISCRTN88136485.

RESULTS

Between 14 September 2010 and 30 September 2014, 88 children were enrolled in the trial, 84 children were randomized (41 assigned to intervention, 43 to control) of whom 77 completed the intervention (38 of 41 (93%) intervention, 39 of 43 (91%) control) and 74 completed follow-up (38 of 41 (93%) intervention, 36 of 43 (84%) control). Six months after intervention there were no significant differences between the groups on disease activity (SAEASI mean difference -3.4 (95%CI -8.5 to 1.7)), quality of life (CDLQI mean difference -0.3 (95%CI -2.0 to 1.4)) and catastrophizing thoughts (JUCCKI/JU subscale mean difference -0.7 (95%CI -1.4 to -0.0)). Immediately and 6 weeks after intervention, disease activity and quality of life were significantly different in favour of alpine climate treatment. Mean differences on SAEASI were -10.1 (95%CI -14.5 to -5.8) and -8.4 (95%CI -12.2 to -4.6) and on CDLQI -1.9 (95%CI -3.3 to -0.5) and -1.5 (95%CI -2.8 to -0.3) immediately and 6 weeks after the intervention, respectively. There were no long-term differences on asthma-related outcomes. Five serious adverse events occurred during the study period, which were not thought to be related to the treatment.

CONCLUSIONS & CLINICAL RELEVANCE

For children with difficult to treat AD, there was no additional long-term benefit of alpine climate treatment, in contrast to the short-term, compared to an outpatient treatment programme in moderate maritime climate, using a personalized integrative multidisciplinary treatment approach.

Using Component-Resolved Diagnostics in the Management of Peanut-Allergic Patients

Instead of relying on crude peanut extract, component-resolved diagnostics (CRD) uses sensitization to allergenic proteins within peanut. In this review, we describe the recent advances and future perspectives of the use of CRD in the management of peanut-allergic patients. There is strong evidence that sensitization to Ara h 2 is the best predictor for clinically relevant peanut allergy in children and adults. Isolated sensitization to other peanut components is only rarely present in patients with systemic reactions to peanut. It is, however, important to remark that cut-off points of sIgE to Ara h 2 that predict tolerance or allergy vary between different study populations, different age groups and geographical regions, and validation studies performed in different settings are necessary to implement cut-offs in daily practice. Future studies should focus on the role of CRD in risk-assessment early in life, predicting long-term tolerance and monitoring treatment responses following immunotherapy.

A systematic review of the effect of thermal processing on the allergenicity of tree nuts

BACKGROUND

Allergenicity of foods can be influenced by processing. Tree nuts are an important source of nutrition and increasingly consumed; however, processing methods are quite variable and data are currently lacking on the effects of processing on allergenicity.

OBJECTIVE

To perform a systematic literature review on the effects of food processing on the allergenicity of tree nuts.

METHODS

A systematic literature search of PubMed and Embase databases was performed, with screening of references, related articles and citations. Studies were included if they assessed the allergenicity or immunogenicity of processed nuts.

RESULTS

The search resulted in 32 articles suitable for analysis. Clinical studies indicate that roasting reduces the allergenicity of hazelnut in individuals with a birch pollen allergy and reactivity to raw hazelnut. Thermal processing may reduce the allergenicity of the PR-10 protein in hazelnut and almond in vitro. The majority of the in vitro studies investigating the allergenicity of nonspecific lipid transfer proteins (nsLTPs) and seed storage proteins in hazelnut, almond, cashew nut, Brazil nut, walnut, pecan nut and pistachio nut show heat stability towards different thermal processing methods.

CONCLUSION

Thermal processing may reduce allergenicity of PR-10 proteins in hazelnut and almond, in contrast to nsLTPs and seed storage proteins. This has important implications for source materials used for IgE testing and food challenges and diet advice.

Moving from peanut extract to peanut components: towards validation of component-resolved IgE tests

BACKGROUND

Replacement of peanut extracts by recombinant peanut components is an important step in allergy serologic testing. Criteria are needed for the unbiased inclusion of patients into a study to validate such a replacement.

METHODS

Plasma samples from 64 peanut-positive children (42 reactors, 22 nonreactors in a double-blind, placebo-controlled food challenge) were used to compare IgE reactivity to six recombinant peanut allergens with reactivity to natural peanut proteins extracted at neutral or low pH. We tested the hypothesis that poor extractability of Ara h 9 and other basic allergens at neutral pH leads to under-representation of patients with such sensitization.

RESULTS

IgE reactivity to the components did not fully explain IgE reactivity to peanut extract in 5 of 32 reactors with IgE to peanut extract ≤100 kUA /l. IgE reactivity to components was stronger than to the extract in 11 plasma samples, which was largely due to a low Ara h 8 reactivity of the extract. IgE reactivity to Ara h 9 was much lower than reactivity to other basic proteins, some of which bound IgE well in the RAST, but lost IgE reactivity upon immunoblotting.

CONCLUSIONS

Conventional peanut extracts are deficient in significant IgE-binding components. The inclusion of patients for a validation study should be based on serology performed with improved peanut reagents to avoid a bias against these under-represented, potentially important allergens. To judge clinical relevance of an allergen, the reagent used for inclusion of patients needs to be efficient in detecting IgE to this component.

Diagnostic value of hazelnut allergy tests including rCor a 1 spiking in double-blind challenged children

BACKGROUND

The diagnostic value of hazelnut allergy tests in double-blind challenged children is largely unknown. The aim of this study was to analyze the performance of current diagnostic tests for hazelnut allergy in children and the effect of spiking.

METHODS

Data of 151 children who underwent a double-blind placebo-controlled food challenge for hazelnut were analyzed. The positive predictive value and negative predictive value (PPV/NPV) of level of specific IgE (sIgE) for hazelnut, the influence of rCor a 1 spiking of the ImmunoCAP, and size of the skin prick test (SPT) for hazelnut were determined, also in relation to the severity of the hazelnut allergy. Reported accidental ingestion leading to an allergic reaction to hazelnut was also analyzed in relation to hazelnut allergy.

RESULTS

Specific IgE ≥0.35 kU(A) /l for hazelnut was a moderate predictor for hazelnut allergy. The spiking decreased the PPV from 41% to 38% and increased the NPV from 91% to 100% for sIgE ≥0.35 kU(A) /l. The maximum reached PPV was 73% for sIgE cutoff of 26 kU(A) /l. Level of sIgE before spiking was significantly different between different grades of severity and was lost after spiking. Skin prick test was a better predictor for hazelnut allergy and severity than the level of sIgE. A history of accidental ingestion leading to an allergic reaction to hazelnut had a predictive value of 59% for hazelnut allergy.

CONCLUSIONS

This study showed a good NPV of diagnostic tests for hazelnut allergy in children which further improved by rCor a 1 spiking. However, the PPVs are moderate and decreased by spiking.

[Double-blind placebo-controlled cow's milk challenge for children in general hospitals]

Every child with possible food allergies has the right to a double-blind, placebo-controlled cow's milk challenge. This test can be performed in the paediatric ward of a non-academic hospital. Challenge with other foodstuffs can lead to more serious side effects and therefore should be considered in a general hospital setting only after extensive experience with double-blind, placebo-controlled challenge for cow's milk has been obtained. Other items of international discussion on double-blind, placebo-controlled challenge in children are: the natural development of tolerance for cow's milk, IgE- versus non-IgE-mediated cow's milk allergy, and the exacerbation of pre-existing eczema during and after double-blind, placebo-controlled challenge.

[Episodes of angioedema in children with C1 esterase inhibitor deficiency]

A 6-year-old boy and a 3.5-year-old girl presented with unexplained episodes of angioedema without urticaria. Low serum C1 esterase inhibitor activity was found in both children. Family history revealed autosomal dominant inheritance in the girl. The boy had a negative family history for angioedema. C1 esterase inhibitor deficiency is a rare but serious condition that may cause oedema of the upper respiratory tract and death by asphyxiation. Episodes of angioedema occur spontaneously, usually subsiding within 48-72 h. Between episodes, the patients are symptom free. Treatment consists of substitution of synthetic C1 esterase inhibitor during episodes of edema carrying a risk of upper airway obstruction. In patients who have more than one episode of severe angioedema per month, daily treatment with tranexamic acid should be considered. Both of these patients were not receiving daily treatment.

Acute allergic reactions in children with AEDS after prolonged cow's milk elimination diets

BACKGROUND

Food allergy is not always correctly diagnosed in children with atopic eczema dermatitis syndrome (AEDS) and treatment with an avoidance diet is not without danger.

METHODS

After admission to our clinic, 11 children with a prolonged cow's milk (CM) elimination diet because of AEDS and sensitization underwent double-blind placebo-controlled food challenge (DBPCFC). Retrospectively, the exposure to CM, sensitization and reactions to accidental ingestion were carefully documented. The DBPCFC was used to evaluate the childrens' current status.

RESULTS

Before the elimination period (median 2.3 years; started before the admission) all 11 children with AEDS were sensitized and had ingested CM (four bottle-fed; seven breast-fed without CM diet of the mother) without the development of acute reactions. The diagnosis of CM allergy was not confirmed by DBPCFC previously. After elimination the AEDS had not improved, but nevertheless the diet was continued. During the elimination period, eight of 11 children developed severe acute allergic reactions to CM after accidental ingestion. In evaluation, in our clinic all 11 children experienced acute allergic reactions to CM during DBPCFC.

CONCLUSION

There is a considerable chance of developing acute allergic reactions to CM after elimination in children with AEDS without previous problems after CM intake.

[Double blind placebo controlled cow's milk provocation for the diagnosis of cow's milk allergy in infants and children]

OBJECTIVE

To test a protocol for a double-blind placebo-controlled cow's milk provocation for the diagnosis of acute allergic reactions to milk in an outpatient setting.

DESIGN

Prospective, descriptive.

METHOD

During the period from June 1, 1999 to February 28, 2001 the protocol was tested on all infants and children who were referred to the Paediatric outpatient clinic of the University Medical Centre on Utrecht with symptoms indicative of cow's milk allergy. The protocol comprised of a phased administration of two test meals, one with a true feed and one with placebo, during the course of one day. In case of allergic symptoms the test was discontinued and the code was broken. A diagnosis of 'cow's milk allergy' was made if the symptoms appeared during the provocation with true feeding.

RESULTS

The test group (n = 154) consisted of 85 boys and 69 girls with ages ranging from 0.25 to 14 years (median 1.5). Acute type reactions to cow's milk occurred in 21 of the children who underwent the provocation. These reactions mainly consisted of cutaneous symptoms (erythema and urticaria). In none of these cases the symptoms were severe enough to require a prolonged stay in the hospital. There were no reactions on placebo meals nor acute reactions during the reintroduction of milk at home.

CONCLUSION

It is possible to perform double-blind placebo-controlled provocations routinely in the diagnostic work-up of children with a suspicion of cow's milk allergy.

Identification of a nonsense mutation in the granulocyte-colony-stimulating factor receptor in severe congenital neutropenia

Severe congenital neutropenia (Kostmann syndrome) is characterized by profound absolute neutropenia and a maturation arrest of marrow progenitor cells at the promyelocyte-myelocyte stage. Marrow cells from such patients frequently display a reduced responsiveness to granulocyte-colony-stimulating factor (G-CSF). G-CSF binds to and activates a specific receptor which transduces signals critical for the proliferation and maturation of granulocytic progenitor cells. Here we report the identification of a somatic point mutation in one allele of the G-CSF receptor gene in a patient with severe congenital neutropenia. The mutation results in a cytoplasmic truncation of the receptor. When expressed in murine myeloid cells, the mutant receptor transduced a strong growth signal but, in contrast to the wild-type G-CSF receptor, was defective in maturation induction. The mutant receptor chain may act in a dominant negative manner to block granulocytic maturation.

Acute hemiparesis as the presenting sign in a heterozygote for ornithine transcarbamylase deficiency

Strokes in children occur in conjunction with cardiac disease, hematological disorders, trauma, intracranial infections and migraine. Recently several inborn errors of metabolism have been recognized as possible causes of stroke-like symptoms. We describe a female heterozygote of ornithine transcarbamylase deficiency, who presented with convulsions and right sided hemiplegia. MR-imaging of the brain demonstrated an acute ischemic lesion in the left hemisphere. In addition to other known metabolic causes of stroke like attacks urea cycle defects should be considered in the differential diagnosis of acute hemiplegia in childhood.