Genetic predisposition to adverse drug reactions in the intensive care unit

The Evolving Role of Next Generation Sequencing in Pediatric Neurosurgery: a Call for Action for Research, Clinical Practice, and Optimization of Care

NGS (Next-Generation Sequencing) is one of the most promising technologies that have truly revolutionized many aspects of clinical practice in recent years. It has been and is increasingly applied in many disciplines of medicine; however, it appears that pediatric neurosurgery despite its great potential has not truly embraced this new technology and is hesitant to employ it in its routine practice and guidelines. In this review, we briefly summarized the developments that lead to the establishment of NGS technology, reviewed the current applications and potentials of NGS in the disorders treated by pediatric neurosurgeons, and lastly discuss the steps we need to take to better harness NGS in pediatric neurosurgery.

Pharmacogenomics of Alzheimer's Disease: Novel Strategies for Drug Utilization and Development

Alzheimer's disease (AD) is a priority health problem in developed countries with a high cost to society. Approximately 20% of direct costs are associated with pharmacological treatment. Over 90% of patients require multifactorial treatments, with risk of adverse drug reactions (ADRs) and drug-drug interactions (DDIs) for the treatment of concomitant diseases such as hypertension (>25%), obesity (>70%), diabetes mellitus type 2 (>25%), hypercholesterolemia (40%), hypertriglyceridemia (20%), metabolic syndrome (20%), hepatobiliary disorder (15%), endocrine/metabolic disorders (>20%), cardiovascular disorder (40%), cerebrovascular disorder (60-90%), neuropsychiatric disorders (60-90%), and cancer (10%).For the past decades, pharmacological studies in search of potential treatments for AD focused on the following categories: neurotransmitter enhancers (11.38%), multitarget drugs (2.45%), anti-amyloid agents (13.30%), anti-tau agents (2.03%), natural products and derivatives (25.58%), novel synthetic drugs (8.13%), novel targets (5.66%), repository drugs (11.77%), anti-inflammatory drugs (1.20%), neuroprotective peptides (1.25%), stem cell therapy (1.85%), nanocarriers/nanotherapeutics (1.52%), and other compounds (<1%).Pharmacogenetic studies have shown that the therapeutic response to drugs in AD is genotype-specific in close association with the gene clusters that constitute the pharmacogenetic machinery (pathogenic, mechanistic, metabolic, transporter, pleiotropic genes) under the regulatory control of epigenetic mechanisms (DNA methylation, histone/chromatin remodeling, microRNA regulation). Most AD patients (>60%) are carriers of over ten pathogenic genes. The genes that most frequently (>50%) accumulate pathogenic variants in the same AD case are A2M (54.38%), ACE (78.94%), BIN1 (57.89%), CLU (63.15%), CPZ (63.15%), LHFPL6 (52.63%), MS4A4E (50.87%), MS4A6A (63.15%), PICALM (54.38%), PRNP (80.7059), and PSEN1 (77.19%). There is also an accumulation of 15 to 26 defective pharmagenes in approximately 85% of AD patients. About 50% of AD patients are carriers of at least 20 mutant pharmagenes, and over 80% are deficient metabolizers for the most common drugs, which are metabolized via the CYP2D6, CYP2C9, CYP2C19, and CYP3A4/5 enzymes.The implementation of pharmacogenetics can help optimize drug development and the limited therapeutic resources available to treat AD, and personalize the use of anti-dementia drugs in combination with other medications for the treatment of concomitant disorders.

Genophenotypic Factors and Pharmacogenomics in Adverse Drug Reactions

Adverse drug reactions (ADRs) rank as one of the top 10 leading causes of death and illness in developed countries. ADRs show differential features depending upon genotype, age, sex, race, pathology, drug category, route of administration, and drug–drug interactions. Pharmacogenomics (PGx) provides the physician effective clues for optimizing drug efficacy and safety in major problems of health such as cardiovascular disease and associated disorders, cancer and brain disorders. Important aspects to be considered are also the impact of immunopharmacogenomics in cutaneous ADRs as well as the influence of genomic factors associated with COVID-19 and vaccination strategies. Major limitations for the routine use of PGx procedures for ADRs prevention are the lack of education and training in physicians and pharmacists, poor characterization of drug-related PGx, unspecific biomarkers of drug efficacy and toxicity, cost-effectiveness, administrative problems in health organizations, and insufficient regulation for the generalized use of PGx in the clinical setting. The implementation of PGx requires: (i) education of physicians and all other parties involved in the use and benefits of PGx; (ii) prospective studies to demonstrate the benefits of PGx genotyping; (iii) standardization of PGx procedures and development of clinical guidelines; (iv) NGS and microarrays to cover genes with high PGx potential; and (v) new regulations for PGx-related drug development and PGx drug labelling.

Investigation of toxicity attenuation mechanism of tetrahydroxy stilbene glucoside in Polygonum multiflorum Thunb. by Ganoderma lucidum

ETHNOPHARMACOLOGICAL RELEVANCE

The idiosyncratic hepatotoxicity of Polygonum multiflorum Thunb. (PM) has attracted great interest, and tetrahydroxy stilbene glucoside (TSG) was the main idiosyncratic hepatotoxicity constituent, but biological detoxification on idiosyncratic hepatotoxicity of PM was not well investigated.

AIM OF THE STUDY

This study aimed to illustrate biological detoxification mechanism on PM-induced idiosyncratic hepatotoxicity by Ganoderma lucidum (G. lucidum).

MATERIALS AND METHODS

G. lucidum was used for biological detoxification of tetrahydroxy stilbene glucoside (TSG)-induced idiosyncratic hepatotoxicity of PM. The TSG consumption and products formation were dynamically determined during transformation using high-performance liquid chromatography coupled with diode-array detection and electrospray ionization tandem mass spectrometry (HPLC-DAD-MSn). The transformation invertases (β-D-glucosidase and lignin peroxidase) were evaluated by using intracellular and extracellular distribution and activity assay. The key functions of lignin peroxidase (LiP) were studied by experiments of adding inhibitors and agonists. The entire TSG transformation process was confirmed in vitro simulated test. The cellular toxicity of TSG and the transformation products was detected by MTT.

RESULTS

A suitable biotransformation system of TSG was established with G. lucidum, then p-hydroxybenzaldehyde and 2,3,5-trihydroxybenzaldehyde can be found as transformation products of TSG. The transformation mechanism involves two extracellular enzymes, β-D-glucosidase and LiP. β-D-glucosidase can remove glycosylation of TSG firstly and then LiP can break the double bond of remaining glycosides. The toxicity of TSG after biotransformation by G. lucidum was attenuated.

CONCLUSIONS

This study would reveal a novel biological detoxification method for PM and explain degradation processes of TSG by enzymic methods.

Propylthiouracil-induced organizing pneumonia: A case report

RATIONALE

Propylthiouracil (PTU) is a common antithyroid drug which can treat hyperthyroidism effectively. PTU is, however, associated to multiple adverse effects. In rare case, PTU can cause interstitial pneumonia.

PATIENT CONCERNS

A 40-year-old woman presented with dyspnea and was diagnosed with pulmonary infection at the first time. After the treatment with moxifloxacin, her symptoms still got worse.

DIAGNOSIS

The lung tissues biopsy confirmed the diagnosis of organizing pneumonia (OP) and the administration of PTU suggested the diagnosis of PTU-induced OP.

INTERVENTION

Withdrawal of PTU and the administration of methylprednisolone.

OUTCOMES

The patient's symptoms relieved significantly 1 month later and lung computed tomography (CT) scan also demonstrated significant reduction of lung lesions.

LESSONS

Here we report the first case of histologically confirmed OP induced by PTU and conduct a literature review of the cases of PTU-induced interstitial pneumonia. The awareness of PTU-induced OP can help physicians reduce the possibility of misdiagnosis.

Hepatotoxicity and hepatoprotection of Polygonum multiflorum Thund. as two sides of the same biological coin

ETHNOPHARMACOLOGICAL RELEVANCE

Polygonum multiflorum Thund., a well-known and commonly-used TCM (Traditional Chinese Medicine) for treating hypertension, hyperlipidemia, premature graying of hair, and etc., has aroused wide concern for its reported potential liver toxicity. Due to its various active ingredients, the mechanisms underlying the hepatotoxicity of raw Polygonum multiflorum Thund (RPM) remain largely unknown.

AIM OF THE STUDY

¹H NMR metabolomics was used to study the mechanism of RPM induced hepatotoxicity and disclosed the existence of hepatotoxicity and hepatoprotection conversion during RPM administration in mice.

MATERIALS AND METHODS

Three dosages of RPM were administered by gavage to mice for consecutive 28 days. The serum and liver samples were collected and then subjected for histopathology observation, biochemical measurement and ¹H NMR metabolic profiling.

RESULTS

RPM caused oxidative stress and mitochondria dysfunction in mice, resulting in significant disturbance in energy metabolism, amino acid metabolism and pyrimidine metabolism and also inducing inflammatory responses. RPM induced hepatotoxicity in an apparent non-linear manner: the most severe in low dosage group, and to a less extent in medium group according to metabolomics analysis. The attenuation of liver injury in mice livers might result from the therapeutic effects, such as anti-oxidative capacity of RPM components.

CONCLUSION

RPM exerted a complicated non-linear manner in healthy recipients, switching between hepatoxicity and hepatoprotection dependent on the dosage and status of the body.

Pharmacogenomics of Medications Commonly Used in the Intensive Care Unit

In the intensive care unit (ICU) setting, where highly variable and insufficient drug efficacies, as well as frequent and unpredictable adverse drug reactions (ADRs) occur, pharmacogenomics (PGx) offers an opportunity to improve health outcomes. However, PGx has not been fully evaluated in the ICU, partly due to lack of knowledge of how genetic markers may affect drug therapy. To fill in this gap, we conducted a review to summarize the PGx information for the medications commonly encountered in the ICU.

The pharmacogenomics of severe traumatic brain injury

Pharmacotherapy for traumatic brain injury (TBI) is focused on resuscitation, prevention of secondary injury, rehabilitation and recovery. Pharmacogenomics may play a role in TBI for predicting therapies for sedation, analgesia, seizure prevention, intracranial pressure-directed therapy and neurobehavioral/psychiatric symptoms. Research into genetic predictors of outcomes and susceptibility to complications may also help clinicians to tailor therapeutics for high-risk individuals. Additionally, the expanding use of genomics in the drug development pipeline has provided insight to novel investigational and repurposed medications that may be useful in the treatment of TBI and its complications. Genomics in the context of treatment and prognostication for patients with TBI is a promising area for clinical progress of pharmacogenomics.

Cis-stilbene glucoside in Polygonum multiflorum induces immunological idiosyncratic hepatotoxicity in LPS-treated rats by suppressing PPAR-γ

The root of Polygonum multiflorum Thunb (PM) has been used in China to treat a variety of diseases, such as constipation, early graying of the hair and hyperlipemia. Recent evidence shows that PM causes idiosyncratic drug-induced liver injury (IDILI) in humans. In this study, we investigated the molecular basis of PM-induced liver injury in a rat model of IDILI based on a non-hepatotoxic dose of LPS. SD rats were orally administered 3 potentially hepatotoxic compounds of PM: cis-stilbene glucoside (cis-SG, 50 mg/kg), trans-SG (50 mg/kg) or emodin (5 mg/kg), followed by injection of LPS (2.8 mg/kg, iv). Serum and liver histology were evaluated 7 h after LPS injection. Among the 3 compounds tested, cis-SG, but not emodin or trans-SG, induced severe liver injury in rats when combined with LPS. The levels of AST and ALT in plasma and inflammatory cytokines in both plasma and liver tissues were markedly elevated. The liver tissues showed increased injury, hepatocyte apoptosis, and macrophage infiltration, and decreased cell proliferation. Microarray analysis revealed a negative correlation between peroxisome proliferator-activated receptor-γ (PPAR-γ) and LPS/cis-SG-induced liver injury. Immunohistochemical staining and RT-PCR results further confirmed that cis-SG significantly inhibited activation of the PPAR-γ pathway in the liver tissues of LPS/cis-SG-treated rats. Pre-treatment with a PPAR-γ agonist pioglitazone (500 g/kg, ig) reversed LPS/cis-SG-induced liver injury, which was associated with inhibiting the nuclear factor kappa B (NF-κB) pathway. These data demonstrate that cis-stilbene glucoside induces immunological idiosyncratic hepatotoxicity through suppressing PPAR-γ in a rat model of IDILI.

Design and evaluation of a pharmacogenomics information resource for pharmacists

OBJECTIVE

To develop and evaluate a pharmacogenomics information resource for pharmacists.

MATERIALS AND METHODS

We built a pharmacogenomics information resource presenting Food and Drug Administration (FDA) drug product labelling information, refined it based on feedback from pharmacists, and conducted a comparative usability evaluation, measuring task completion time, task correctness and perceived usability. Tasks involved hypothetical clinical situations requiring interpretation of pharmacogenomics information to determine optimal prescribing for specific patients.

RESULTS

Pharmacists were better able to perform certain tasks using the redesigned resource relative to the Pharmacogenomic Knowledgebase (PharmGKB) and the FDA Table of Pharmacogenomic Biomarkers in Drug Labeling. On average, participants completed tasks in 107.5 s using our resource, compared to 188.9 s using PharmGKB and 240.2 s using the FDA table. Using the System Usability Scale, participants rated our resource 79.62 on average, compared to 53.27 for PharmGKB and 50.77 for the FDA table. Participants found the correct answers for 100% of tasks using our resource, compared to 76.9% using PharmGKB and 69.2% using the FDA table.

DISCUSSION

We present structured, clinically relevant pharmacogenomic FDA drug product label information with visualizations to help explain the relationships between gene variants, drugs, and phenotypes. The results from our evaluation suggest that user-centered interfaces for pharmacogenomics information can increase ease of access and comprehension.

CONCLUSION

A clinician-focused pharmacogenomics information resource can answer pharmacogenomics-related medication questions faster, more correctly, and more easily than widely used alternatives, as perceived by pharmacists.

The direct cost of care among surgical inpatients at a tertiary hospital in south west Nigeria

Introduction

This study was conducted to assess the direct cost of care and its determinants among surgical inpatients at university College Hospital, Ibadan.

Methods

A retrospective review of records of 404 inpatients that had surgery from January to December, 2010 was conducted. Information was extracted on socio-demographic variables, investigations, drugs, length of stay (LOS) and cost of carewith a semi-structured pro-forma. Mean cost of care were compared using t-test and Analysis of variance (ANOVA). Linear regression analysis was used to identify determinants of cost of care. Level of significance of 5% was used. In year 2010 $1 was equivalent to 150 naira ($1=₦ 150).

Results

The median age of patients was 30 years with inter-quartile range of 13-42 years. Males were 257(63. 6%). The mean overall cost of care was ₦66,983 ± ₦31,985. Cost of surgery is about 50% of total cost of care. Patient first seen at the Accident and Emergency had a significantly higher mean cost of care of ß = ₦17,207(95% CI: ₦4,003 to ₦30,410). Neuro Surgery (ß=₦36,210), and Orthopaedic Surgery versus General Surgery(ß=₦10,258),and Blood transfusion (ß=₦18,493) all contributed to cost of care significantly. Increase of one day in LOS significantly increased cost of care by ₦2,372. 57.

Conclusion

The evidence evaluated here shows that costs and LOS are interrelated. Attempt at reducing LOS will reduce the costs of care of surgical inpatient.

Comparison of delivery strategies for pharmacogenetic testing services

The number and use of pharmacogenetic tests to assess a patient's likelihood of response or risk of an adverse event is expanding across medical specialties and becoming more prevalent. During this period of development and translation, different approaches are being investigated to optimize delivery of pharmacogenetic services. In this paper, we review pre-emptive and point-of-care delivery approaches currently implemented or being investigated and discuss the advantages and disadvantages of each approach. The continued growth in knowledge about the genetic basis of drug response combined with development of new and less expensive testing technologies and electronic medical records will impact future delivery systems. Regardless of delivery approach, the currently limited knowledge of health professionals about genetics generally or PGx specifically will remain a major obstacle to utilization.

Approaches for dosage individualisation in critically ill patients

INTRODUCTION

Pharmacokinetic variability in critically ill patients is the result of the overlapping of multiple pathophysiological and clinical factors. Unpredictable exposure from standard dosage regimens may influence the outcome of treatment. Therefore, strategies for dosage individualisation are recommended in this setting.

AREAS COVERED

The authors focus on several approaches for dosage individualisation that have been developed, ranging from the well-established therapeutic drug monitoring (TDM) up to the innovative application of pharmacogenomics criteria. Furthermore, the authors summarise the specific population pharmacokinetic models for different drugs developed for critically ill patients to improve the initial dosage selection and the Bayesian forecasting of serum concentrations. The authors also consider the use of Monte Carlo simulation for the selection of dosage strategies.

EXPERT OPINION

Pharmacokinetic/pharmacodynamics (PK/PD) modelling and dosage individualisation methods based on mathematical and statistical criteria will contribute in improving pharmacologic treatment in critically ill patients. Moreover, substantial effort will be necessary to integrate pharmacogenomics criteria into critical care practice. The lack of availability of target biomarkers for dosage adjustment emphasizes the value of TDM which allows a large part of treatment outcome variability to be controlled.

Drug induced interstitial lung disease

With an increasing number of therapeutic drugs, the list of drugs that is responsible for severe pulmonary disease also grows. Many drugs have been associated with pulmonary complications of various types, including interstitial inflammation and fibrosis, bronchospasm, pulmonary edema, and pleural effusions. Drug-induced interstitial lung disease (DILD) can be caused by chemotherapeutic agents, antibiotics, antiarrhythmic drugs, and immunosuppressive agents. There are no distinct physiologic, radiographic or pathologic patterns of DILD, and the diagnosis is usually made when a patient with interstitial lung disease (ILD) is exposed to a medication known to result in lung disease. Other causes of ILD must be excluded. Treatment is avoidance of further exposure and systemic corticosteroids in patients with progressive or disabling disease.

Introduction to drug pharmacokinetics in the critically ill patient

Despite regular use of drugs for critically ill patients, overall data are limited regarding the impact of critical illness on pharmacokinetics (PK). Designing safe and effective drug regimens for patients with critical illness requires an understanding of PK. This article reviews general principles of PK, including absorption, distribution, metabolism, and elimination, and how critical illness can influence these parameters. In the area of drug absorption, we discuss the impact of vasopressor use, delayed gastric emptying and feeding tubes, and nutrient interactions. On the topic of drug distribution, we review fluid resuscitation, alterations in plasma protein binding, and tissue perfusion. With drug metabolism, we discuss hepatic enzyme activity, protein binding, and hepatic blood flow. Finally, we review drug elimination in the critically ill patient and discuss the impact of augmented renal clearance and acute kidney injury on drug therapies. In each section, we highlight select literature reviewing the PK impact of these conditions on a drug PK profile and, where appropriate, provide general suggestions for clinicians on how to modify drug regimens to manage PK challenges.