Adverse Drug Reaction Probability Scale Research Articles

Acute hypokalemic periodic paralysis possibly precipitated by albuterol

An episode of acute hypokalemic paralysis associated with the use of inhaled albuterol is described. A 34-year-old woman admitted to the emergency department reported the development of pain and diffuse paralysis of the extremities and torso shortly after using an albuterol inhaler. At age 18, she had been diagnosed with hyokalemic periodic paralysis (HPP), a disorder of muscle membrane excitability caused by serum potassium depletion that can lead to life-threatening neuromuscular and cardiovascular complications. After a 15-year period of episodically recurring HPP symptoms despite long-term acetazolamide use, she was switched to spironolactone therapy and had experienced no HPP exacerbations for about 1 year. On her arrival in the emergency department, the patient's serum potassium concentration was 1.8 meq/L and she was mildly tachycardic (heart rate of 125 beats/min). After careful supplementation to gradually increase the serum potassium concentration to 5.4 meq/L, the patient slowly regained movement and strength in her extremities. Application of the adverse drug reaction probability scale of Naranjo et al. to this case yielded a score of 3, indicating that albuterol was possibly the cause of the patient's HPP exacerbation. Beta-2-adrenergic agonists and several other medications can affect serum potassium levels; although the potential risks posed by the use of such drugs in patients with a history of HPP are unclear, cautious use in the context of known HPP is advised. A patient previously diagnosed with HPP experienced an exacerbation of HPP possibly induced by inhaled albuterol treatment.

Treatment of antipsychotic-induced hyperprolactinemia with bromocriptine: A case report

INTRODUCTION Previous literature has highlighted an increase in morbidity and mortality associated with antipsychotic use in persons with severe mental illnesses (SMI), which include schizophrenia and bipolar disorder. Drug-induced hyperprolactinemia is a function of dopamine blockade in the anterior pituitary. Elevated prolactin levels are often accompanied by symptoms of decreased libido and erectile dysfunction (ED) in men, and galactorrhea and amenorrhea in women. However, the extent to which antipsychotic (AP) use is associated with sexual dysfunction has not been extensively reported. Hyperprolactinemia may also increase the risk for osteopenia.

Memory loss during lenalidomide treatment: a report on two cases

BackgroundThere are many reports of cognitive dysfunction in patients receiving chemotherapy or targeted therapies. Many antineoplastic agents may be involved in the condition also known as “chemo brain” or “chemo fog”.Case presentationTwo male patients (aged 41 and 70) with multiple myeloma developed severe, rapidly progressing cognitive impairment (mostly involving episodic memory) and loss of independence in activities of daily living during lenalidomide-based treatment. On withdrawal of the drug, one patient recovered normal cognitive function and independence in activities of daily living, whereas mild cognitive impairment persisted in the other patient. The Naranjo Adverse Drug Reaction Probability Scale score was 6 out of 13 for the first patient and 5 out of 13 for the second, suggesting a probable causal relationship between the adverse event and lenalidomide administration.ConclusionLenalidomide may induce particular cognitive disorders (notably episodic memory impairments) in some patients. The drug’s putative neurotoxicity is probably promoted by specific risk factors (such as previous chemotherapy, prior mild cognitive impairment, age and the presence of cerebrovascular lesions).

Dysarthria induced by irinotecan in a patient with colorectal cancer

Successful management and subsequent prevention of a rare adverse drug reaction (ADR) associated with irinotecan chemotherapy are reported. A 49-year-old man with meta-static colon cancer undergoing treatment with i.v. irinotecan (180 mg/m(2) to be infused over 120 minutes) as part of a multidrug chemotherapy regimen developed dysarthria about 90 minutes into irinotecan infusions on two occasions. In both instances, the dysarthric symptoms (numbness of the tongue and difficult speech) resolved after the discontinuation of irinotecan and administration of hydration therapy. Brain imaging studies showed no functional or structural abnormalities; several concomitantly administered medications, including metoclopramide, palonosetron, and other components of the chemotherapy regimen, were deemed unlikely to have played a causal or contributory role in the episodes of dysarthria. Application of the ADR probability scale of Naranjo et al. in this case yielded a score of 9, indicating a definite ADR caused by irinotecan. For subsequently administered chemotherapy cycles, the duration of the patient's irinotecan infusions was increased (to 180 minutes for cycles 3-5 and to 240 minutes for cycles 6-12). Dysarthria did not recur and, with the exception of transient tongue twisting during two of the 180-minute infusions, he completed the full course of irinotecan therapy without a recurrence of dysarthric symptoms. Irinotecan-induced dysarthria in a man being treated for colon cancer resolved with the discontinuation of irinotecan. With increases in the duration of infusion, the man received additional irinotecan treatments with no recurrence of dysarthria.

Gastrointestinal bleeding secondary to interaction of Artemisia absinthium with warfarin

Artemisia absinthium, also known as wormwood, is used widely as an herbal medicine. In this report, we introduce an 82-year-old Turkish woman who was treated with warfarin for atrial fibrillation and was hospitalized for gastrointestinal bleeding as a result of extremely elevated international normalized ratio (INR) after consumption of A. absinthium. Naranjo adverse drug reaction probability scale score was 6, which indicated a probable relationship between the patient's elevated INR and her concomitant use of wormwood and warfarin. Clinicians should be vigilant about potential dangers of herbal medicines taken with conventional drugs, and patients taking drugs with a narrow therapeutic index, such as warfarin, should be educated about avoiding consumption of herbal medicines.

A case of montelukast induced hypercholesterolemia, severe hypertriglyceridemia and pancreatitis

Montelukast sodium is a leukotriene inhibitor, and competitively antagonizes cys-LT1 receptor and used widely and effectively in treating allergic rhinitis, bronchial asthma and allied respiratory conditions. This case report outlines a rare case of montelukast induced hypercholesterolemia, severe hypertriglyceridemia and acute pancreatitis in a 22 years old male patient. The patient was taking 10 mg oral montelukast daily for allergic rhinitis. Although his symptoms improved considerably, after 2 months of therapy, he experienced unusual weight gain and got admitted with severe pain abdomen. Clinical and other relevant investigation findings revealed the presence of acute pancreatitis with associated hypercholesterolemia and severe hypertriglyceridemia. There were no evidences of any other possible hereditary, surgical, metabolic, infective, organic or other pathologic causes giving rise to these conditions. De-challenge was done and the patient was treated conservatively resulting in reversal of the diseased state. Naranjo adverse drug reaction probability scale suggested that it was ‘probable’ that oral administration of montelukast was responsible for the acute pancreatitis associated with hypercholesterolemia and severe hypertriglyceridemia. There is only a singular and confirmed reported case of montelukast induced hypertriglyceridemia from India. For patients taking montelukast for a long duration, routine lipid profile monitoring should be done, and if these patients present with symptoms of epigastric and periumbilical pain with vomiting, provisions for screening acute pancreatitis might be warranted.

Two cases of hallucination in elderly patients due to a probable interaction between flu immunization and tramadol

Annual vaccination against influenza (FluV) is indicated forindividuals at risk of developing medical complicationsbecause of underlying pathological conditions [1]. Most ofthese patients are likely to be exposed to drug treatmentsoccasionally characterised by a narrow therapeutic index.The possible effects of FluV on the metabolism of thesedrugs have not been investigated in detail [2].We report on an adverse drug reaction (ADR) in two elderlypatients, a woman and a man aged 85 and 84 years, respective-ly, highly homogeneous in terms of pathological manifesta-tions, who developed hallucinations after the administration ofFluV (Vaxigrip® and Intanza®, respectively). Both patients atthe moment of vaccination had been receiving treatment withtramadol for several months due to chronic lumbar pain.The female patient had tolerated tramadol (100 mg/day)well, and no interactions were evident with the concomitanttherapy (Table 1). Six days after vaccination she developedhallucinations resulting in equilibrium imbalance and a majorfall. Neurological examinations carried out in the EmergencyDepartment (ED), including computed axial tomography(CAT) scan, did not reveal organic causes. The neurologistsuspecting the iatrogenic nature of the hallucinations,suspended the tramadol treatment and the hallucinationsdisappeared within 36 h. The following day, the patient de-cided to take 100 mg of tramadol and once again developedhallucinations with confusion and amnesic episodes. She wasadmitted again to the ED, and a second neurological examalso did not reveal any organic cause for the symptoms.Tramadol treatment was suspended and the hallucinationsdisappeared once again, this time within 48 h.In the male patient tramadol (25 mg/day) had also beenwell tolerated; no interactions were evident with the con-comitant therapy (Table 1). Five days after vaccination thepatient was hospitalised for hallucinations, psychomotoragitation, hypotension and malaise. Tramadol withdrawalled to an improvement in the severity of the hallucinations,which completely disappeared in 2 days. The neurologicalexaminations including CAT scan did not reveal possibleorganic causes.The Naranjo ADR probability scale indicates a “proba-ble” relationship between the female patient’s developmentof ADRs and therapy with tramadol, and a “possible” rela-tionship for the male patient. In both patients tramadol waswell tolerated, and ADRs developed in both cases only afterimmunisation against influenza. Both patients denied usingherbal remedies.Tramadol is inactivated by cytochrome P450 (CYP) 3A4and CYP2B6 [3, 4] and metabolised by CYP2D6 to itsactive metabolite M1. FluV decreases CYP3A4 activity,with peak inactivation occurring 7 days after vaccination[5, 6]. This reduction in CYP3A4 activity is greater inelderly people [5] and is consistent with the time course of

A case of thrombotic thrombocytopenic purpura associated with bupropion

To report a case of bupropion-associated thrombotic thrombocytopenic purpura (TTP) syndrome. A 55-year-old man was admitted with complaints of diarrhea, acute renal failure, and confusion ~ 54 days after bupropion initiation for smoking cessation. Subsequently he had a tonic-clonic seizure and had to be intubated because of altered consciousness. Laboratory findings were compatible with microangiopathic hemolytic anemia. He was diagnosed as TTP for which the Naranjo adverse drug reaction probability scale indicated a probable relationship with bupropion (a score of 5). He was treated with plasma exchange, systemic corticosteroids, hemodialysis and recovered fully. Bupropion is an anti-depressant drug also indicated for smoking cessation. It has widely reported neuropsychiatric and allergic adverse effects; however, TTP associated with bupropion has only been reported once. The clinical course of TTP in this case was compatible with TTP related to acute, immune mediated drug toxicity, which suggests that auto-antibodies might have been responsible. Given the fact that the clinical condition is compatible with acute, immune-mediated TTP syndrome, we suggest bupropion deserves evaluation for auto-antibody induction. Prescribers should be aware of the possible risk of thrombocytopenia and TTP.

De novo Tardive Tourette-like syndrome after prolonged combination depot and oral neuroleptic therapy.

Introduction Tardive Tourette-like syndrome is recognised by the observation of several motor and vocal tics often in individuals receiving psychotropic medications and can happen within 1-3 months of treatment. Clinical case We report a case which is unique in its onset of Tardive Tourette-like syndrome comprising of vocal, motor tics and coprolalia after more than three decades of treatment with combination depot and oral neuroleptics. Discussion Use of the Naranjo Adverse Drug Reaction Probability Scale indicates a probable relationship between the onset of Tardive Tourettism and the antipsychotic therapy in this patient. This was in contrast to earlier reports which noted earlier onset and partial reversal with termination or change of medications. Clinicians need to pay heed to the emergence of late-onset Tourettism in order to better manage its manifestation and prevent its worsening in the context of holistic care for patients with neuropsychiatric conditions including schizophrenia.

Rash Associated with Dabigatran Etexilate

Patients experiencing atrial fibrillation are at an increased risk for thromboembolic events. Therefore, anticoagulation therapy is imperative to prevent thrombus formation and stroke. Dabigatran etexilate was approved by the Food and Drug Administration in 2010 as anticoagulant prophylaxis for patients with nonvalvular atrial fibrillation. The frequency of dermatologic reactions to dabigatran etexilate is estimated in the product labeling to be less than0.1%. To date, five cases of dabigatran etexilate-associated rash have reported, including three published cases. We describe the sixth reported case of dabigatran etexilate-associated rash, in a 59-year-old man with a history of atrial fibrillation who received dabigatran etexilate 150mg twice/day for atrial flutter before cardioversion. The patient had taken dabigatran etexilate for 5days before the rash was noted on hospital admission. He had no known previous drug allergies, and his platelet count, serum creatinine concentration, and hepatic function were normal. The rash resolved 7days after the discontinuation of dabigatran etexilate, and the patient was stabilized on warfarin therapy. Use of the Naranjo Adverse Drug Reaction Probability Scale indicated a probable relationship (score of 5) between the patient's development of the rash and dabigatran etexilate therapy. Clinicians should be aware of this adverse effect of dabigatran etexilate and monitor for dermatologic reactions during follow-up visits.

Methylprednisolone Sodium Succinate–Associated Macroglossia in a Critically Ill Patient

Allergic hypersensitivity reactions are a rare adverse effect of corticosteroids. Previous reports have identified patients who developed symptoms of urticaria, dyspnea, hypotension, bronchospasm, and angioedema occurring within minutes to an hour after corticosteroid administration. A 35-year-old woman is described who developed an atypical reaction of isolated macroglossia after receiving intravenous methylprednisolone sodium succinate for myasthenic crisis. Macroglossia was identified on day 2 of therapy and worsened through day 5. On day 5, she was transitioned to prednisone 50mg daily administered by feeding tube. Tongue swelling improved by day 7 and on day 10, the patient was extubated. The patient required reintubation due to stridor, but received a tracheostomy and was weaned off mechanical ventilation by day 15. The reaction was not confirmed with skin-prick tests, intradermal tests, or a drug rechallenge; however, she had previously received and tolerated all other drugs administered during this time. Due to the timing of administration and onset of symptoms, we feel this adverse drug reaction was likely due to administration of methylprednisolone. Applying the Naranjo adverse drug reaction probability scale to this case, a score of six was obtained, indicating a probable association between the administration of methylprednisolone and the development of macroglossia. As intravenous corticosteroids are often used in the treatment of allergic reactions, they may be overlooked as a cause of macroglossia and other allergic reactions; therefore, practitioners need to be aware of the possibility of this adverse effect secondary to corticosteroid administration. In the event of methylprednisolone sodium succinate-induced macroglossia, alternative nonesterified corticosteroids, such as dexamethasone or prednisone, should be considered if continuation of therapy is required.

A Case of Panic Attack Induced by St John’s Wort

To the Editor: St John’s wort (Hypericum perforatum L) is one of the oldest and best investigated medicinal herbs.1 Hypericum extracts have been shown to be significantly effective in treating mild-to-moderate depression.2 To the best of our knowledge, we report the first case of panic attack induced by a single dose of St John’s wort extract. Case report. Mr A, an otherwise healthy 35-year-old man, was admitted to the hospital for gradually increased trembling and fear of dying. He stated that, 2 hours after he drank a glass of St John’s wort extract (because of difficulty falling asleep), he became restless, anxious, and agitated. He also reported palpitations, sweating, chest discomfort, shortness of breath, nausea, blurred vision, and feelings of derealization. The patient denied hallucinations or delusions. An electrocardiogram showed tachycardia. Vital signs were remarkable for a pulse of 110 bpm and respiratory rate of 22 breaths/min. Improvement was seen in the panic state, and vital signs returned to normal within 25 minutes after oral alprazolam 1 mg was administered. He denied any psychiatric history (apart from difficulty falling asleep 1 or 2 days a week), current stressors, or use of alcohol. Family history was noncontributory. When questioned, Mr A reported a similar episode after drinking a glass of St John’s wort extract approximately 2 months previously. The patient met the Diagnostic and Statistical Manual of Mental Disorders, Fourth Edition, diagnostic criteria for panic attack. According to the Naranjo Adverse Drug Reaction Probability Scale,3 there was a probable association between St John’s wort and panic attack. After being discharged, Mr A denied any further panic attacks at his 1- and 3-month visits. Although the exact mechanism of action is not known, there is good evidence from in vitro experiments that St John’s wort extracts are potent but nonspecific inhibitors of the synaptosomal reuptake of serotonin, norepinephrine, and dopamine.4 In vivo studies have shown that Hypericum extracts lead to a down-regulation of β-adrenergic receptors and an up-regulation of 5-HT2 receptors.4 The most important risk associated with Hypericum extracts is reported to be the interactions with other drugs.5 However, as reported here, a single dose of St John’s wort extract can induce a panic attack. It is crucial to investigate herbal drug use in patients presenting with psychiatric complaints. It is important that clinicians become aware of the potential psychiatric adverse effects associated with St John’s wort, which is a widely used medicinal herb, and explain these effects to their patients.

Higher than expected rates of seizures associated with the use of ertapenem in older hospitalized patients

BackgroundUse of carbapenems is expected to increase with rising prevalence of multidrug-resistant bacteria. Available literature indicates that the incidence of seizure with ertapenem use ranges from 0.2% to 0.5% in adults. However, anecdotal clinical experience suggests that the frequency of seizures in frail geriatric patients could be higher. AimWe sought to estimate the rate of seizures with the use of ertapenem in older hospitalized patients and to identify possible predisposing factors for their occurrence. MethodsWe performed a retrospective chart review for hospital episodes of patients who were admitted to the department of geriatric medicine of an acute care hospital and received at least one dose of ertapenem between October 2009 and September 2010. ResultsChart reviews for 116 patients were conducted. The mean age of the study population was 82.9 years [standard deviation (SD) = 8.1] and 69% of the patients were female. The mean number of comorbidities was 8.6 (SD = 3.7) and the mean number of assisted or dependent activities of daily living out of 5 was 3.5 (SD = 2.0). Seizures occurred in six (5.17%) hospitalized patients. The Naranjo Adverse Drug Reaction Probability Scale revealed a causality relationship graded as “possible” in two episodes and “probable” in the remaining four episodes. Patients who experienced seizures were significantly younger (mean age: 75.7 vs. 83.3 years, p = 0.023) and had fewer comorbidities (5.5 vs. 8.8, p = 0.033). Seizure occurrence had statistically nonsignificant associations with a history of central nervous system disorders and previous seizures. ConclusionWe found a higher rate of seizures amongst older hospitalized patients who were using ertapenem than reported in existing literature. Further studies should include a wider population of older hospitalized patients and compare seizure incidence with the use of carbapenem alternatives.

THE COMPARISON BETWEEN MONOTHERAPY AND POLYTHERAPY IN EPILEPSY IDIOPATHIC GENERALISED TONIC CLONIC

The prevalence of epilepsy in the world reachs 5-20 per 1000 population. In Indonesia, the prevalence of epilepsy is approximately at 0.5-1.2%. Antiepilepsy drug has an important role in the epilepsy treatment. This study was aimed to know the effectiveness and safety of monotherapy treatment compared to polytherapy in terms of seizure frequency, seizure-free duration, and adverse drug reaction. This study was the observational research. The data were collected prospectively using instruments i.e.: seizure diaries and APS (Adverse Drug Reaction Probability Scale). Subject of this study were epileptic patient with idiopathic generalized tonic clonic who receive either polytherapy or monotherapy in neurological clinic of Dr. Sardjito Hospital on May-June 2012 period, which fulfilled the inclusion criteria. The data from monotherapy and polytherapy group was analysed in term of seizure frequency, seizure-free duration and adverse drug reaction. Result showed that monotherapy treatment more effective in controlling seizure (reduce the frequency of seizure) compared to polytherapy (<0.05). Percentage of seizure free was 83% in monotherapy compared to 48% in polytherapy. The prevalence of adverse drug reaction was about 20% in monotherapy and 14% in polytherapy. Based on the interview, although monotherapy caused more adverse drug reaction than that in polytherapy, the drug adverse reaction in monotherapy was milder and did not annoy patient convenience. Keywords: Epilepsy, Idiopathic Generalised Tonic Clonic, Monotherapy, Polytherapy, Adverse Drug Reaction

Desvenlafaxine-Induced Worsening of Hypertension

Desvenlafaxine-Induced Worsening of Hypertension

Neurologic Adverse Effects of Ranolazine in an Elderly Patient with Renal Impairment

Ranolazine, an antianginal agent, has activity at muscle and neuronal sodium channels. Congenital genetic mutations to sodium channels in humans and supratherapeutic ranolazine concentrations in animal models have produced similar neurologic adverse reactions. We describe a case of neurologic adverse effects in an 81-year-old woman with coronary artery disease, renal impairment, and mild neurologic disease who received ranolazine for symptomatic control of a non-ST-segment elevation myocardial infarction. Just over 48 hours after a dose increase, she experienced new-onset dysarthia, dysmetria, hallucinations, worse tremors, and difficulty with word finding. Her workup for acute stroke and infectious causes was negative. Her symptoms abated 2days after ranolazine was discontinued. The patient was at risk for ranolazine adverse effects due to the high dose administered and her advanced age, renal impairment, and baseline mild neurologic disease. Use of the Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 5) between the patient's neurologic adverse events and the ranolazine therapy. To our knowledge, this is the first case report illustrating rare but debilitating neurologic adverse effects of ranolazine. Health care practitioners should be aware of the adverse effects of ranolazine and avoid doses greater than500mg twice/day in patients older than80years or those with a creatinine clearanceof less than 30ml/minute.

Azithromycin-Induced Hepatotoxicity

Objective To report a case of hepatotoxicity in a patient receiving azithromycin. Case Summary A 38-year-old female was admitted for an acute exacerbation of her liver disease. The patient received a course of azithromycin 2 weeks prior to admission for a respiratory tract infection. On admission, the patient had elevated liver function tests (LFTs), ascites, jaundice with sclera icterus, and abdominal pain. Etiologies such as infection and worsening liver disease were ruled out, and the patient's symptoms and transaminitis were attributed to azithromycin-induced hepatotoxicity. The patient was medically managed with diuretics and discharged after the symptoms stabilized and LFTs were trending down. Discussion There are 6 previous case reports of patients experiencing azithromycin-induced hepatotoxicity. The patient's presentation and onset of symptoms after azithromycin initiation were similar to other patients. Although this patient had a history of steatohepatitis, progression of liver disease was ruled out and other etiologies were considered unlikely. The patient's laboratory values supported cholestatic liver injury, and the most likely cause of the transaminitis and symptoms was attributed to azithromycin. Although azithromycin is usually well-tolerated and liver injury is a rare adverse effect, there is increasing literature surrounding azithromycin-induced hepatotoxicity. The Naranjo adverse drug reaction probability scale revealed a possible interaction between azithromycin and the hepatotoxic adverse event. Conclusions We report a possible case of azithromycin-induced hepatotoxicity. Even though hepatotoxicity is an uncommon side effect of azithromycin, prescribers should be cognizant of this potential adverse effect in order to discontinue therapy as necessary and prevent re-exposure to the medication.

Hot Flashes in a Young Girl: A Wake-up Call Concerning Serenoa repens Use in Children

Extracts of the plant Serenoa repens are widely used in male adults for the treatment of benign prostatic hyperplasia. Recently, therapy with S repens has been proposed as a "natural" alternative to conventional treatments for male androgenetic alopecia as well as for other hair disorders. Telogen effluvium is a form of alopecia characterized by abnormality of hair cycling, resulting in excessive loss of telogen hair. We report the case of an 11-year-old girl presenting hot flashes that appeared after treatment of telogen effluvium with a food supplement containing S repens that lasted for ~2 months. When use of the product was discontinued, the hot flashes no longer occurred. Four months after the start of S repens intake and 45 days from the cessation of therapy, the girl experienced menarche at the age of 11 years. The Naranjo adverse drug reaction probability scale indicated a probable relationship (score of 6) between the appearance of hot flashes and the intake of S repens. A correlation between exposure to S repens and the onset of menarche is not certain, but it cannot be excluded. Medicinal products or food supplements containing S repens are generally well tolerated in male adults, but we believe that their use in pediatric patients should be better evaluated.

Vancomycin‐Induced Thrombocytopenia Without Isolation of a Drug‐Dependent Antibody

Vancomycin is a glycopeptide antibiotic used in the treatment of gram-positive infections including methicillin-resistant Staphylococcus aureus (MRSA). The most common adverse reaction to vancomycin is red man syndrome, which is a histaminergic reaction causing a rash on the upper torso, neck, and face after rapid infusion of the drug. Less commonly, vancomycin has been associated with thrombocytopenia. The etiology is believed to be the induction of drug-dependent antibodies, which in turn cause immune-mediated destruction of platelets. We describe a 41-year-old man who received two courses of vancomycin for the treatment of MRSA pneumonia and then experienced a decline in platelet count to a nadir of 15 x 10³/mm³. Vancomycin was discontinued, doxycycline was started, and the patient's platelet count rebounded over the next 6 days. The patient was readmitted to the hospital 2 months later for MRSA bacteremia and was rechallenged with vancomycin. He again experienced a decline in platelet count. Vancomycin was discontinued, and daptomycin was started. The patient's platelet count rebounded to normal levels over the next 5 days. Although the patient experienced acute thrombocytopenia after vancomycin exposure, no bleeding complications occurred, and the patient's platelet count rebounded to normal after the discontinuation of vancomycin. The patient had no other known risk factors for the development of rapid thrombocytopenia. Use of the Naranjo adverse drug reaction probability scale indicated a definite relationship (score of 9) between the patient's development of thrombocytopenia and vancomycin therapy. Although vancomycin was the presumed cause of thrombocytopenia in this patient, no drug-dependent antibody was isolated from blood samples collected after both exposures to vancomycin (analyzed by using a screening assay to identify drug-dependent antibodies to vancomycin [developed by the BloodCenter of Wisconsin]). Although the evidence supporting vancomycin induction of antibody-mediated destruction of platelets was lacking, further studies delineating alternate mechanisms of platelet destruction are warranted. Therefore, even in the absence of a positive antibody test, vancomycin should still be considered in the differential diagnosis as a cause of drug-induced thrombocytopenia.

Probable levetiracetam-related serum alkaline phosphatase elevation

BackgroundLevetiracetam (LEV) is an antiepileptic drug with a favorable tolerability and safety profile with little or no effect on liver function.Case presentationHere, we reported an epileptic pediatric patient who developed a significant elevation in serum alkaline phosphatase level (ALP) during LEV monotherapy. Moreover, the serum ALP level was surprisingly decreased to normal after LEV discontinuation. The Naranjo Adverse Drug Reaction Probability Scale score was 6, indicating firstly LEV was a probable cause for the increased serum ALP.ConclusionsCautious usage and concerns of the LEV-associated potential ALP elevation should be considered when levetiracetam is prescribed to epilepsy patients, especially pediatric patients.