Phenytoin Intoxication in a Patient Receiving a Therapeutic Dose for Postoperative Seizure Prophylaxis: A Case Study.

OBJECTIVE: Phenytoin is commonly prescribed to prevent postoperative seizures. Despite the rarity of the CYP2C9 genetic polymorphism, which may result in poor phenytoin metabolism, in the Thai population, the authors report a case of phenytoin toxicity in a patient with poor metabolism administered with a standard dose of phenytoin. CASE REPORT: A 58-year-old Thai woman presented to the outpatient clinic with a 2-day history of nausea, vomiting, and dizziness. She underwent craniotomy for tumor removal 2 weeks after being diagnosed with tuberculum sellae meningioma. After the surgery, she was prescribed 300 mg of phenytoin daily to prevent seizures. During the physical examination, ataxia, horizontal nystagmus, and cerebellar abnormalities were observed, with an initial serum phenytoin concentration of 58.85 mg/L. The brain imaging results were unremarkable. Omeprazole was the only recognized drug interaction; however, it is highly unlikely to account for this condition. Pharmacogenetic investigation of CYP2C9 revealed a homozygous CYP2C9*3/*3 mutation, which is indicative of suboptimal drug metabolism and can reduce phenytoin metabolism by 50%. This patient was administered repeated dosages of activated charcoal over the course of 2 days. Her symptoms eventually subsided, with the phenytoin levels dropping to 29.51 mg/L. CONCLUSIONS: In the absence of an overdose history or drug-drug interaction, CYP2C9 polymorphism should be suspected in patients with phenytoin toxicity. In such situations, the phenytoin dosage must be decreased and monitored closely.

Antiepileptic drug-induced severe granulomatous interstitial nephritis.

Granulomatous interstitial nephritis (GIN) is a type of tubulointerstitial nephritis characterised by tubulointerstitial infiltration of mononuclear cells and eosinophils. It accounts for about 6% of all tubulointerstitial nephritis and is detected in ∼0.5%-0.9% of all renal biopsies. GIN has been linked to several antibiotics, non steroidal anti-inflammatory drugs (NSAIDs), and granulomatous disorders like tuberculosis and sarcoidosis but is rarely reported with anti-epileptic medications like phenytoin and levetiracetam. We present a case report of a man in his early 20's with previously normal renal function who developed GIN following levetiracetam and phenytoin consumption for 7 years. After withdrawal of the causative drug and starting steroid therapy, his kidney function gradually improved. In cases of GIN, medication history is important in the evaluation of aetiology.

Enhancement of receptor-mediated calcium responses by phenytoin through the suppression of calcium excretion in human gingival fibroblasts.

BACKGROUND AND OBJECTIVES: Gingival overgrowth caused by phenytoin is proposed to be associated with Ca2+ signaling; however, the mechanisms that increase the intracellular Ca2+ concentration ([Ca2+ ]i ) are controversial. The current study aimed to elucidate the mechanism underlying the phenytoin-induced increase in [Ca2+ ]i in human gingival fibroblasts (HGFs). METHODS: Effects of 100 µM phenytoin on [Ca2+ ]i in HGFs were examined at the single-cell level using fluorescence images of fura-2 captured by an imaging system consisting of an EM-CCD camera coupled to an inverted fluorescence microscope at room temperature. RESULTS: Exposure of HGFs to 100 µM phenytoin induced a transient increase in [Ca2+ ]i in the absence of extracellular Ca2+ , indicating that the phenytoin-induced increase in [Ca2+ ]i does not require an influx of extracellular Ca2+ . In addition, phenytoin increased [Ca2+ ]i in HGFs depleted of intracellular Ca2+ stores by thapsigargin, indicating that neither Ca2+ release from stores nor inhibition of Ca2+ uptake is involved. Furthermore, the phenytoin-induced [Ca2+ ]i elevation was reduced to 18.8% in the absence of extracellular Na+ , and [Ca2+ ]i elevation upon removal of extracellular Na+ was reduced to 25.9% in the presence of phenytoin. These results imply that phenytoin increases [Ca2+ ]i of HGFs by suppressing the Na+ /Ca2+ exchanger. Suppression of intracellular Ca2+ excretion is thought to enhance the Ca2+ responses induced by various stimuli. Analysis at the single-cell level showed that stimulation with 1 µM ATP or 3 µM histamine increased [Ca2+ ]i in 20-50% of cells, and [Ca2+ ]i increased in many unresponsive cells in the presence of phenytoin. CONCLUSION: Our findings demonstrate that phenytoin induced increase in [Ca2+ ]i by the inhibition of Ca2+ efflux in HGFs. It was also found that phenytoin strongly enhanced small Ca2+ responses induced by stimulation with a low concentration of ATP or histamine by inhibiting Ca2+ efflux. These findings suggest a possibility that phenytoin causes drug-induced gingival overgrowth by interacting with inflammatory bioactive substances in the gingiva.

Pseudotumour cerebri due to phenytoin in a child.

Pseudotumour cerebri is a manifestation of intracranial hypertension in an otherwise normal individual. We hereby report phenytoin-induced pseudotumour cerebri in a 9-year-old boy who received phenytoin as a prophylactic anticonvulsant following surgical removal of unifocal Langerhans cell histiocytosis involving the right frontal bone. The child was evaluated for headache and diplopia after starting phenytoin and on evaluation was found to have bilateral sixth nerve palsy. The only abnormality detected was an elevated cerebrospinal fluid pressure. Withdrawal of phenytoin resulted in complete resolution of symptoms. Despite meticulous literature search, we found only 1 other report of phenytoin induced pseudotumour cerebri. We report this case to highlight the need to consider this entity whenever a patient presents with new onset or persistent headache and visual symptoms soon after starting a medication since a high degree of suspicion is needed to arrive at the diagnosis and to take appropriate steps before it progresses to harmful complications such as vision loss.

Longstanding Phenytoin Use as a Cause of Progressive Dyspnea.

CASE PRESENTATION: A 54-year-old South African man with a medical history of type 2 diabetes mellitus, seizure disorder, OSA, and latent TB presented to the ER with gradually progressive dyspnea over months. He also reported occasional dry cough and fatigue at presentation but denied fever, chills, chest pain, leg swelling, palpitations, or lightheadedness. He was treated with a course of levofloxacin for presumed community-acquired pneumonia as an outpatient without improvement and had tested negative for COVID-19. He denied occupational or environmental exposures or sick contacts, though he had traveled back to South Africa 1 year before presentation. He had complex partial seizures for the past 22 years, which had been well controlled on phenytoin (300 mg daily). His other home medications included dulaglutide, sertraline, and atorvastatin and had no recent changes. He quit smoking 30 years ago after smoking one pack per day for 10 years.

Uso de membrana de celulosa oxidada post-gingivectomía en hiperplasia gingival inducida por fenitoína / Use of oxidized cellulose regenerated post-gingivectomy on ginigival hyperplasia induced by phenytoin

Introducción: La hiperplasia gingival es una condición benigna caracterizada por el aumento de volumen de la encía. Algunos fármacos, factores genéticos, aparatología y placa dentobacteriana son factores que pueden inducir esta condición. Objetivo: Devolver la anatomía a la encía brindando una mejor estética y permitiendo una óptima higiene oral. Material y métodos: Paciente masculino de 20 años de edad con antecedentes de fenitoína presenta aumento de volumen en la encía. Resultados: Se obtuvieron resultados estéticos y funcionales satisfactorios con el tratamiento quirúrgico y el uso de membrana de celulosa oxidada. Conclusión: En el manejo de la hiperplasia gingival es importante el enfoque no quirúrgico como control de placa dentobacteriana y medidas de higiene del mismo paciente (AU)

Introduction: Gingival hyperplasia is a benign condition characterized for the grown on the gingival volume. Some drugs, genetic, orthodontic and dental plaque are some factors that can induce this condition. Objective: To return the gingival anatomy, providing a better aesthetic allowing also good oral hygiene. Material and methods: A male 20 years of age with medical history of phenytoin display grown on the gingival volume. Results: Aesthetic and functional results were achieved with the surgical treatment and the oxidized cellulose membrane. Conclusion: In the gingival hyperplasia management is important de non-surgical approach, as dental plaque control and oral hygiene of the patient (AU)

Topical phenytoin administration accelerates the healing of acetic acid-induced colitis in rats: evaluation of transforming growth factor-beta, platelet-derived growth factor, and vascular endothelial growth factor.

Ulcerative colitis (UC), limited to the colon's innermost lining, has become a global health problem. Immunomodulatory and monoclonal antibodies are used to treat UC despite their side effects and limitations. Phenytoin is used to heal wounds owing to its effects on growth factors, collagen, and extracellular matrix synthesis. This study aimed to evaluate the effect of topical phenytoin administration in UC. Phenytoin was administered in two doses during the treatment. Eighty male Wistar rats (230-280 g) were divided randomly into ten groups of sham, control, hydrocortisone, phenytoin 1%, and 3% groups in 6- or 12-day treatment protocols. The UC model was induced by the administration of acetic acid 4% into the colon. Animals were killed on the 7th and 13th postoperative days. The main outcome measures included body weight loss, microscopic score, and ulcer index measured using specific criteria. Growth factors were measured by western blotting. Results illustrated that body weight loss was reversed in the treatment groups. Ulcer index had decreased on 6- and 12-day treatment protocols. Microscopic scores in 6-day enema treatment significantly decreased compared to the control groups. Transforming growth factor-beta (TGFß) significantly increased in a time-dependent manner and platelet-derived growth factor (PDGF) and vascular endothelial growth factor (VEGF) significantly increased in a time- and dose-dependent manner in phenytoin 1% and 3% in the 6- and 12-day protocols. Phenytoin dose- and time-dependently reversed weight loss. In addition, histopathological parameters included microscopic scores, and the ulcer index was decreased through the induction of growth factors TGFß, PDGF, and VEGF and consequently accelerated ulcer healing.

Utility of monitoring the serum levetiracetam concentration for intraoperative seizure control during awake craniotomy.

Awake craniotomy is an established procedure for resecting brain tumors in eloquent lesions, and intraoperative seizure is one of the most important complications. Phenytoin is normally used to control intraoperative seizures. Recently, phenytoin was replaced with levetiracetam at our institution because the latter has fewer side effects. While the phenytoin dose is calibrated in accordance with the serum concentration, there is currently no consensus on a method of monitoring the serum concentration of levetiracetam or the effective concentration range needed to control intraoperative seizures during awake craniotomy. The present study therefore aimed to determine whether monitoring the serum levetiracetam concentration is useful for controlling intraoperative seizures during awake craniotomy. The intraoperative serum concentration of levetiracetam during awake craniotomy was measured in 34 patients and compared with that of phenytoin in 33 patients undergoing the same procedure. The levetiracetam concentration inversely correlated with body surface area (BSA) and estimated glomerular filtration rate (eGFR). Levetiracetam was superior to phenytoin in terms of the correlation between the serum concentration and the dose adjusted for BSA and eGFR (correlation coefficient, 0.49 vs 0.21). Furthermore, the serum levetiracetam concentration in patients with intraoperative seizures was below the 95% confidence interval (CI) of the regression line whereas the serum phenytoin concentration of two patients with seizures was within the 95% CI, indicating that evaluating the serum levetiracetam concentration against the BSA and eGFR-adjusted dosage may be useful in preventing intraoperative seizures during awake craniotomy by allowing prediction of the seizure risk and enabling more accurate dosage calibration.

Levetiracetam versus fosphenytoin as a second-line treatment after diazepam for status epilepticus: study protocol for a multicenter non-inferiority designed randomized control trial.

BACKGROUND: Status epilepticus (SE) is an emergency condition for which rapid and secured cessation is important. Phenytoin and fosphenytoin, the prodrug of phenytoin with less severe adverse effects, have been recommended as second-line treatments. However, fosphenytoin causes severe adverse events, such as hypotension and arrhythmia. Levetiracetam reportedly has similar efficacy and higher safety for SE; however, evidence to support its use for adult SE is lacking. In the present study, a non-inferiority designed multicenter randomized controlled trial (RCT) is being conducted to compare levetiracetam with fosphenytoin after diazepam as a second-line treatment for SE. METHODS: This multicenter, prospective, and open-label RCT is conducted in emergency departments. Between December 23, 2019, and March 31, 2023, 176 patients with convulsive SE transported to an emergency room will be randomized into a fosphenytoin group and levetiracetam group at a ratio of 1:1. The definition of SE is "continuous seizures longer than 5 min or discrete seizures longer than 2 min with intervening consciousness disturbance." In both groups, diazepam is initially administered at 1-20 mg, followed by intravenous fosphenytoin at 22.5 mg/kg or intravenous levetiracetam at 1000-3000 mg. The primary outcome is the seizure cessation rate within 30 min. Seizure recurrence within 24 h, severe adverse events, and intubation rate within 24 h are secondary outcomes. DISCUSSION: The present study was approved and conducted as an initiative study of the Japanese Association for Acute Medicine. If non-inferiority is identified, the society will pursue an application for the national health insurance coverage of levetiracetam for SE via a public knowledge-based application. TRIAL REGISTRATION: Japan Registry of Clinical Trials jRCTs031190160 . Registered on December 13, 2019.

Síndrome DRESS asociado a fenitoína: informe de caso / DRESS syndrome associated with phenytoin: case report

El síndrome DRESS es una reacción adversa dermatológica que puede presentarse debido a diversos medicamentos, y constituye uno de los diagnósticos más importantes por encima del síndrome de Stevens-Johnson. Se trata de un caso relacionado con una reacción adversa de muy baja frecuencia, que está documentada en la literatura científica, a varios medicamentos, entre ellos la fenitoína. Por lo mencionado, la publicación de estos casos resulta escasa y limitada. Las principales preocupaciones del paciente relacionadas con su cuadro clínico radicaban en el gran compromiso cutáneo que lo llevó a hospitalización, dolor e incomodidad, por el cual recurrió al manejo tópico generalizado con vaselina. Los hallazgos clínicos relevantes fueron: eosinofilia severa, ulceraciones cutáneas, hepatitis química y fiebre. Con los hallazgos del cuadro clínico y la evaluación de la escala RegiSCAR se hace el diagnóstico de síndrome DRESS inducido por fenitoína. Se suspende la fenitoína, se inicia levetiracetam y se administran corticosteroides y acetaminofén con evolución favorable. (AU)

DRESS syndrome is a dermatological adverse reaction can occur due to various medications, being one of the most important diagnoses above Steven-Johnson syndrome. This is a case related to a very low frequency adverse reaction that is documented in the scientific literature to several medicines among those, the phenytoin. Therefore, the publication of these cases is scarce and limited. The main concerns of the patients related to their clinical picture were due to the great cutaneous compromise that lead to hospitalization, pain and discomfort for which they resorted to generalized topical management with vaseline (petrolatum). Relevant clinical findings were severe eosinophilia, skin ulcerations, chemical hepatitis and fever. With clinical picture findings and evaluation of the RegiSCAR scale, the diagnosis of Phenytoin-induced DRESS syndrome is made. Phenytoin is discontinued, levetiracetam is started and corticosteroids and acetaminophen are administrated with favorable evolution. (AU)

Agrandamiento gingival inducido por fenitoínas / Phenytoin induced gingival enlargement

Se entiende por agrandamiento gingival el incremento en masa y volumen del tejido gingival. Se considera una condición benigna de la cavidad oral, por lo general de manejo rutinario, que logra regularse con medidas simples de control del biofilm microbiano. El agrandamiento gingival puede ser producido por diversas condiciones clínicas, hereditarias, deficiente higiene oral o fármacos. La epilepsia afecta a 1% de la población mundial y requiere el uso de fármacos antiepilépticos o anticonvulsivantes para lograr su control, dentro de éstos la fenitoína actúa como un bloqueador selectivo de los canales de sodio sensibles al voltaje y constituye uno de los fármacos más empleados por su capacidad en el control de crisis focales y generalizadas. La fenitoína se ha relacionado con los agrandamientos gingivales como uno de sus efectos adversos, los cuales se incluyen dentro de las enfermedades por fármaco inducidas en la cavidad oral. El objetivo de este artículo es brindar la información necesaria sobre el manejo correcto de pacientes con agrandamiento gingival producido por fenitoínas y a la vez poder conocer las consecuencias de estos fármacos en la cavidad oral (AU)

Gingival enlargement means the increase in mass and volumen of the gingival tissue. It is considered a benign condition of the oral cavity, usually of routine management, wich can be regulated with simple measures of biofilm control. The gingival enlargement can be produced by diverse clinical conditions, hereditary deficient oral higiene or drugs. Epilepsy affects 1% of the world population and requires the use of antiepileptic or anticonvulsant drugs to achieve its control, within these phenytoin acts as selective blocker or voltage ­ sensitive sodium channels and is one of the most used grugs for its ability to control focal and generalized crises. Phenytoin has been linked to gingival enlargement as one of its adverse effects which is included within the drug diseases induced in the oral cavity. The objective of this article is to provide the necessary information on the correct managment of patients with gingival enlargemen produced by phenytoins and at the same time to know the consequences of these drugs in the oral cavity (AU)

Incidence of hyponatremia in patients given levetiracetam vs. phenytoin for early posttraumatic seizure prophylaxis.

BACKGROUND: Levetiracetam and phenytoin are comparable for acute posttraumatic seizure(PTS) prophylaxis. Levetiracetam-induced hyponatremia has been reported in non-trauma patients. We studied hyponatremia in posttraumatic intracranial hemorrhage(ICH) patients receiving either drug. METHODS: Retrospective review of patients with ICH receiving PTS prophylaxis was performed. Patients were categorized by degree of sodium nadir: normal, mild, moderate, or severe, and analyzed by levetiracetam versus phenytoin. Patients were matched 2:1 regarding age and injury severity score(ISS). Incidence and treatment for hyponatremia was examined. RESULTS: 1735 ICH patients received PTS prophylaxis over an 8-year period. After exclusions and matching, there were 282 phenytoin and 564 levetiracetam patients. Age, ISS and initial sodium were comparable between the matched cohorts. There was no clinically significant difference in the rate or degree of hyponatremia. Treatment was more common in levetiracetam patients. DISCUSSION: There was a small but clinically insignificant difference in the incidence of hyponatremia in traumatic ICH patients receiving levetiracetam vs. phenytoin for PTS prophylaxis. There was an increased rate of intervention for hyponatremia in the levetiracetam group, possibly due to a coincidental preventive paradigm shift.

Anticonvulsant hypersensitivity syndrome: clinic case and literature review.

INTRODUCTION: The anticonvulsant hypersensitivity syndrome is a rare adverse reaction in which the skin, lymph nodes and internal organs are affected. It is usually caused by classic anticonvulsants such as phenytoin, carbamazepine or phenobarbital. CASE REPORT: Here we present the case of a 25-year-old woman from Córdoba, Argentina, who suffered a severe reaction to oxcarbazepine with a rash, lymphadenopathy, hepatitis and an unusual analytic. Clinical abnormalities were reversed after oxcarbazepine was terminated and treatment with diphenhydramine and dexamethasone was initiated. DISCUSSION: DRESS syndrome is a hypersensitivity reaction that takes weeks to manifest, and is characterized by rash, leukocytosis with eosinophilia, adenopathies, liver involvement, and reactivation of the herpes virus 6, being more frequent in carbamazepine or phenytoin, and in rare cases to oxcarbazepine. CONCLUSIONS: In general, this strong medicine is not taken into account as a cause of hypersensitivity, reports suggest that it could be related to cases similar to this one, and studies that are more targeted are required, due to the morbidity and mortality of the syndrome.

Introducción: El síndrome de hipersensibilidad a los anticonvulsivantes es una reacción adversa rara en la que se ven afectados la piel, los ganglios linfáticos y los órganos internos. Generalmente es causada por anticonvulsivos clásicos como fenitoína, carbamazepina o fenobarbital. Caso clínico: Aquí presentamos el caso de una mujer de 25 años de Córdoba, Argentina, que sufrió una reacción severa a la oxcarbazepina con una erupción cutánea, linfadenopatías, hepatitis y un analítico inusual. Las anormalidades clínicas se revirtieron después de que se terminara la oxcarbazepina y se inició el tratamiento con difenhidramina y dexametasona. Discusión: El síndrome DRESS es una reacción de hipersensibilidad que tarda semanas en manifestarse, y se caracteriza por exantema, leucocitosis con eosinofilia, adenopatías, afectación hepática, y reactivación del virus herpes 6, siendo más frecuente ante carbamazepina o fenitoína, y en raros casos a oxcarbazepina. Conclusiones: Por lo general, este medicamento fuerte no se toma en cuenta como causa de hipersensibilidad, los informes sugieren que podría estar relacionado con casos similares a este, y se requieren estudios que sean más dirigidos, debido a la morbimortalidad del síndrome.

Crown Ether Nanovesicles (Crownsomes) Repositioned Phenytoin for Healing of Corneal Ulcers.

Drug repositioning is an important drug development strategy as it saves the time and efforts exerted in drug discovery. Since reepithelization of the cornea is a critical problem, we envisioned that the anticonvulsant phenytoin sodium can promote reepithelization of corneal ulcers as it was repurposed for skin wound healing. Herein, our aim is to develop novel crown ether-based nanovesicles "Crownsomes" of phenytoin sodium for ocular delivery with minimal drug-induced irritation and enhanced efficacy owing to "host-guest" properties of crown ethers. Crownsomes were successfully fabricated using span-60 and 18-crown-6 and their size, morphology, polydispersity index, ζ potential, drug loading efficiency, conductivity, and drug release were characterized. Crownsomes exhibited favorable properties such as formation of spherical nanovesicles of 280 ± 18 nm and -26.10 ± 1.21 mV surface charges. Crownsomes depicted a high entrapment efficiency (77 ± 5%) with enhanced and controlled-release pattern of phenytoin sodium. The optimum crownsomes formulation ameliorated ex vivo corneal drug permeability (1.78-fold than drug suspension) through the corneal calcium extraction ability of 18-crown-6. In vivo study was conducted utilizing an alkali-induced corneal injury rabbit model. Clinical and histopathological examination confirmed that crownsomes exhibited better biocompatibility and minimal irritation due to complex formation and drug shielding. Further, they enhanced corneal healing, indicating their effectiveness as a novel drug delivery system for ocular diseases.

Uso de testosterona en mujeres: un comentario sobre el consenso global sobre el uso de la terapia de testosterona para mujeres / Global consensus position statement on the use of testosterone therapy for women

Las mujeres han sido tratadas por décadas con testosterona intentando aliviar una gran variedad de síntomas con riesgos y beneficios inciertos. En la mayoría de los países, la testosterona se prescribe "off-label", de modo que las mujeres están utilizando compuestos y dosis ideadas para tratamientos en hombres. En este sentido, varias sociedades médicas de distintos continentes adoptaron recientemente por consenso una toma de posición sobre los beneficios y potenciales riesgos de la terapia con testosterona en la mujer, explorar las áreas de incertidumbre e identificar prácticas de prescripción con potencial de causar daño. Las recomendaciones con respecto a los beneficios y riesgos de la terapia con testosterona se basan en los resultados de ensayos clínicos controlados con placebo de al menos 12 semanas de duración. A continuación se comentan las recomendaciones. (AU)

There are currently no clear established indications for testosterone replacement therapy for women. Nonetheless, clinicians have been treating women with testosterone to alleviate a variety of symptoms for decades with uncertainty regarding its benefits and risks. In most countries, testosterone therapy is prescribed off-label, which means that women are using testosterone formulations or compounds approved for men with a modified dose for women. Due to these issues, there was a need for a global Consensus Position Statement on testosterone therapy for women based on the available evidence from placebo randomized controlled trials (RCTs). This Position Statement was developed to inform health care professionals about the benefits and potential risks of testosterone therapy intended for women. The aim of the Consensus was to provide clear guidance as to which women might benefit from testosterone therapy; to identify symptoms, signs, and certain conditions for which the evidence does not support the prescription of testosterone; to explore areas of uncertainty, and to identify any prescribing practices that have the potential to cause harm. (AU)

Phenytoin Seizure Prophylaxis Therapy Resulting in Severe Thrombocytopenia After Brain Tumor Debulking Surgery.

BACKGROUND Phenytoin is an antiepileptic drug that is usually prescribed as a prevention treatment for tonic-clonic seizures or partial seizures, and as a prophylaxis for the neurosurgical related seizures. Phenytoin administration has several drawbacks; one drawback phenytoin-induced thrombocytopenia, which is a rare and significant adverse event. We report a rare adverse event after phenytoin prophylaxis therapy after a brain tumor debulking surgery, which resulted in severe unpredicted thrombocytopenia. CASE REPORT A 40-year-old male with no known health problems started to have an on/off headaches and loss of memory. Clinical investigations revealed a right frontal brain lesion. On the first day of admission, the patient was managed on neurosurgical seizure prophylaxis therapy of 100 mg intravenous phenytoin every 8 hours and 4 mg oral dexamethasone every 6 hours. On the fifth day of hospital admission, the patient underwent tumor debulking surgery. Twenty-four hours post-surgery, the patient's platelet level dropped to 26×109/L. Severe thrombocytopenia was managed first by transfusion of 17 units of platelets and by cessation of intravenous phenytoin plus the starting of 500 mg levetiracetam orally twice daily. Further management included infusion of 34 grams (0.4 g/kg) intravenous immunoglobulin (IVIG) over 5 days. Five days later, the patient gradually recovered with a platelet count of 239×109/L. CONCLUSIONS Phenytoin-induced thrombocytopenia is considered a rare event, but it has life-threatening consequences. The first and cornerstone management of this event is the cessation of phenytoin, followed by consideration of appropriate management based on the level of thrombocytopenia severity, and avoiding concomitant therapy of phenytoin and the use of dexamethasone as neurosurgical-related seizure prophylaxis.

A first-in-human study of the novel metabolism-based anti-cancer agent SM-88 in subjects with advanced metastatic cancer.

Purpose SM-88 (D,L-alpha-metyrosine; racemetyrosine) is a novel anti-cancer agent, used with melanin, phenytoin, and sirolimus (SMK Therapy). This pilot first-in-human study characterized the safety, tolerability, and efficacy of SMK Therapy in subjects with advanced metastatic cancer. Methods All subjects (n = 30) received SMK Therapy for an initial 6 week Cycle (5 days on, 2 off per week) and continued if well tolerated. Safety signals, clinical response, overall survival, progression free survival (PFS), and quality of life changes were assessed. Results The most common drug related adverse events were hyperpigmentation and rash. All drug related adverse events were mild to moderate in intensity. Following treatment with SMK Therapy, 4 subjects achieved complete response, 6 partial response, and 17 stable disease according to Response Evaluation Criteria in Solid Tumors (RECIST) 1.1 (total clinical benefit 90%). Responses were observed within 6 weeks, and continued to improve, with 3 complete and 3 partial responders achieving best response after at least 3.2 months. Durable stable disease was observed, lasting a median duration of 11 months (range 1-31 months). Median overall survival for all subjects was 29.8 months, and median PFS was 13 months. Following 6 weeks of treatment, most (83.3%) subjects showed an improvement in Eastern Cooperative Oncology Group (ECOG) score and an improvement in the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ 30) global health status (baseline 61.2 ± 25.0; end of Cycle 1 80.7 ± 14.7; n = 29; p < 0.001). Conclusions The results of this study support continued development of SM-88.

Association of Antiepileptic Medications with Outcomes after Allogeneic Hematopoietic Cell Transplantation with Busulfan/Cyclophosphamide Conditioning.

High-dose busulfan (BU) followed by high-dose cyclophosphamide (CY) before allogeneic hematopoietic cell transplantation (HCT) has long been used as treatment for hematologic malignancies. Administration of phenytoin or newer alternative antiepileptic medications (AEMs) prevents seizures caused by BU. Phenytoin induces enzymes that increase exposure to active CY metabolites in vivo, whereas alternative AEMs do not have this effect. Lower exposure to active CY metabolites with the use of alternative AEMs could decrease the risk of toxicity but might increase the risk of recurrent malignancy after HCT. Previous studies have not determined whether outcomes with alternative AEMs differ from those with phenytoin in patients treated with BU/CY before allogeneic HCT. We studied a cohort of 2155 patients, including 1460 treated with phenytoin and 695 treated with alternative AEMs, who received BU/CY before allogeneic HCT between 2004 and 2014. We found no differences suggesting decreased overall survival or relapse-free survival or increased risks of relapse, nonrelapse mortality, acute or chronic graft-versus-host disease, or regimen-related toxicity associated with the use of alternative AEMs compared with phenytoin. The risk of dialysis was lower in the alternative AEM group than in the phenytoin group. Alternative AEMs are safe for prevention of seizures after BU administration and can avoid the undesirable toxicities and drug interactions caused by phenytoin.

Phenytoin versus levetiracetam as prophylaxis for postcraniotomy seizure in patients with no history of seizures: systematic review and meta-analysis.

OBJECTIVEDe novo seizure following craniotomy (DSC) for nontraumatic pathology may adversely affect medical and neurological outcomes in patients with no history of seizures who have undergone craniotomies. Antiepileptic drugs (AEDs) are commonly used prophylactically in patients undergoing craniotomy; however, evidence supporting this practice is limited and mixed. The authors aimed to collate the available evidence on the efficacy and tolerability of levetiracetam monotherapy and compare it with that of the classic AED, phenytoin, for DSC.METHODSPubMed, Embase, Web of Science, and the Cochrane Library were searched for studies that compared levetiracetam with phenytoin for DSC prevention. Inclusion criteria were adult patients with no history of epilepsy who underwent craniotomy with prophylactic usage of phenytoin, a comparator group with levetiracetam treatment as the main treatment difference between the two groups, and availability of data on the numbers of patients and seizures for each group. Patients with brain injury and previous seizure history were excluded. DSC occurrence and adverse drug reaction (ADR) were evaluated. Seizure occurrence was calculated using the Peto odds ratio (POR), which is the relative effect estimation method of choice for binary data with rare events.RESULTSData from 7 studies involving 803 patients were included. The DSC occurrence rate was 1.26% (4/318) in the levetiracetam cohort and 6.60% (32/485) in the phenytoin cohort. Meta-analysis showed that levetiracetam is significantly superior to phenytoin for DSC prevention (POR 0.233, 95% confidence interval [CI] 0.117-0.462, p < 0.001). Subgroup analysis demonstrated that levetiracetam is superior to phenytoin for DSC due to all brain diseases (POR 0.129, 95% CI 0.039-0.423, p = 0.001) and tumor (POR 0.282, 95% CI 0.117-0.678, p = 0.005). ADRs in the levetiracetam group were cognitive disturbance, thrombophlebitis, irritability, lethargy, tiredness, and asthenia, whereas rash, anaphylaxis, arrhythmia, and hyponatremia were more common in the phenytoin group. The overall occurrence of ADR in the phenytoin (34/466) and levetiracetam (26/432) groups (p = 0.44) demonstrated no statistically significant difference in ADR occurrence. However, the discontinuation rate of AEDs due to ADR was 53/297 in the phenytoin group and 6/196 in the levetiracetam group (POR 0.266, 95% CI 0.137-0.518, p < 0.001).CONCLUSIONSLevetiracetam is superior to phenytoin for DSC prevention for nontraumatic pathology and has fewer serious ADRs that lead to discontinuation. Further high-quality studies that compare levetiracetam with placebo are necessary to provide evidence for establishing AED guidelines.