MyMedR

Controversy of proton pump inhibitor and clopidogrel interaction: a review

Tan HJ

J Dig Dis, 2010 Dec;11(6):334-42.

PMID: 21091895 DOI: 10.1111/j.1751-2980.2010.00466.x

A proton pump inhibitor (PPI) is often co-prescribed with clopidogrel to reduce the gastrointestinal risk of bleeding ulcers in patients following acute coronary syndrome or a stent implant. However, the safety issue of such practice has been scrutinized after some studies reporting an increased incidence of cardiovascular events and mortality, although there have also been contrary research reports. This has lead to a warning statement from the US Food and Drug Administration cautioning the concomitant use of PPI and clopidogrel. This review examines the evidence of PPI as gastroprotective agent, histamine H(2) antagonists as an alternative therapy, the influence of PPI on the antiplatelet effect of clopidogrel, and the controversies of various studies.

An unusual rash and end-stage renal failure

Tan HJ, Eadington D

Hosp Med, 2001 Mar;62(3):176-7.

PMID: 11291470

Extragastrointestinal manifestations of Helicobacter pylori infection: facts or myth? A critical review

Tan HJ, Goh KL

J Dig Dis, 2012 Jul;13(7):342-9.

PMID: 22713083 DOI: 10.1111/j.1751-2980.2012.00599.x

Helicobacter pylori (H. pylori) infection is reported to be associated with many extragastrointestinal manifestations, such as hematological diseases [idiopathic thrombocytopenic purpura (ITP) and unexplained iron deficiency anemia (IDA)], cardiovascular diseases (ischemic heart diseases), neurological disorders (stroke, Parkinson's disease, Alzheimer's disease), obesity and skin disorders. Among these, the best evidence so far is in ITP and unexplained IDA, with high-quality studies showing the improvement of IDA and ITP after H. pylori eradication. The evidence of its association with coronary artery disease is weak and many of the results may be erroneous. The role of H. pylori infection in affecting serum leptin and ghrelin levels has attracted a lot of attention recently and available data to date have been conflicting. There have also been many uncontrolled, small sample studies suggesting an association between H. pylori infection and neurological disorders or chronic urticaria. However, more studies are required to clarify such proposed causal links.

Fulltext Infective endocarditis in pregnancy complicated by septic embolization to the cerebellum

Tan HJ, Rabani R, Noorfaizan S

Med J Malaysia, 2007 Aug;62(3):249-50.

PMID: 18246919 MyJurnal

This report describes a pregnant lady in early trimester that was admitted with fever and left loin pain and was initially treated as presumed pyelonephritis. Subsequently she was found to have infective endocarditis with vegetation on the mitral valve. The course of her illness was complicated by acute pulmonary edema and septic embolization to the cerebellum. A decompressive craniectomy and resection of the lateral lobe of cerebellum was performed. Although the presenting features and risk factors are well described, the atypical presentations of infective endocarditis in pregnancy remain a diagnostic challenge for the treating physician. This report highlights the importance of rapid detection of endocarditis in pregnancy and the treatment of systemic complications.

Changing epidemiology of Helicobacter pylori in Asia

Tan HJ, Goh KL

J Dig Dis, 2008 Nov;9(4):186-9.

PMID: 18959588 DOI: 10.1111/j.1751-2980.2008.00344.x

As in developed societies, the prevalence of Helicobacter pylori has declined rapidly in Asia. This has been shown in both seroprevalence-based and endoscopy-based studies. While the decline in the incidence of gastric cancer has now been observed, a decrease in peptic ulcer disease has not been so clearly evident. This apparent paradox can be explained by an increase in non-H. pylori associated ulcers - such as those related to non-steroidal anti-inflammatory drugs or idiopathic ulcers. The increase of gastroesophageal reflux disease in Asia has been widely observed and commented on and its relationship to the decline in H. pylori speculated upon. However there have been few conclusive studies from Asia on this subject. While the improved diagnosis and elimination of H. pylori has contributed to its decline, a more basic change involving large segments of the Asian population must be responsible. An improvement in hygiene and living conditions that results from more affluent Asian societies is thought to be a possible cause.

Corpus callosum infarction in uncontrolled diabetes mellitus

Ng CF, Tan HJ

Acta Neurol Belg, 2021 Oct;121(5):1335-1337.

PMID: 34184193 DOI: 10.1007/s13760-021-01729-8

Fulltext Parietal Hand Weakness in a Patient with Astrocytoma

Ng CF, Tan HJ

J Neurosci Rural Pract, 2022 Jan;13(1):164-166.

PMID: 35110942 DOI: 10.1055/s-0041-1741568

Fulltext Disseminated histoplasmosis in AIDS: a report of three patients

Tan HJ, Cheong I, Muhaizan WM

Med J Malaysia, 2000 Jun;55(2):259-62.

PMID: 19839156

Histoplasmosis is a fungal infection caused by Histoplasma capsulatum. Although uncommon, it should be considered among the list of important opportunistic infections in severely immunocompromised patients. Patients living with AIDS are at particular risk of disseminated histoplasmosis. Diagnosis requires a high level of clinical suspicion. The infection is best confirmed by demonstration of the organism in tissue specimens or by culture. Amphotericin B is the most effective drug for severe disseminated histoplasmosis. Response is good but life-long maintenance is required to prevent relapse.

Fulltext Preeruptive Unilateral Cerebellar Ataxia in an Immunocompetent Adult: A Rare Case of Varicella

Ng CF, Ong BH, Tan HJ

J Neurosci Rural Pract, 2018 5 5;9(2):281-283.

PMID: 29725187 DOI: 10.4103/jnrp.jnrp_461_17

Fulltext A Case of Herpes Simplex Virus Type 1 (HSV-1) Encephalitis as a Possible Complication of Cosmetic Nasal Dermal Filler Injection

Khoo CS, Tan HJ, Sharis Osman S

Am J Case Rep, 2018 Jul 13;19:825-828.

PMID: 30002360 DOI: 10.12659/AJCR.909883

BACKGROUND Dermal fillers are increasingly used for medical and aesthetic purposes in clinical practice. Common complications following filler injections include bruising, itching, infections, allergic reactions, and tissue necrosis. This case is the first report of Herpes simplex virus type 1 (HSV-1) encephalitis as a possible complication of dermal filler injection. CASE REPORT A 27-year-old woman with no past medical history presented with altered mental state, headaches, and seizures. She had a nasal dermal filler injection for aesthetic purpose five weeks before her acute presentation. A diagnosis of HSV-1 encephalitis was made based on brain imaging with computed tomography and magnetic resonance imaging (MRI) findings that showed bilateral frontotemporal lobe hyperintensity. Analysis of her cerebrospinal fluid (CSF) confirmed the presence of HSV-1 DNA. Despite anti-viral treatment with acyclovir, she developed postencephalitic syndrome. CONCLUSIONS This case report highlights the possibility that among the complications of the use of cosmetic dermal fillers, the transmission of HSV-1 and the development of HSV-1 encephalitis should be recognized.

Fulltext Longitudinally Extensive Transverse Myelitis in Highly Active Relapsing-remitting Multiple Sclerosis

Ng CF, Remli R, Tan HJ

Neurol India, 2021 11 9;69(5):1412-1413.

PMID: 34747827 DOI: 10.4103/0028-3886.329533

Transverse myelitis in multiple sclerosis is typically a short cord lesion with patchy distribution. Rarely, longitudinally extensive transverse myelitis can be seen in those with highly active disease or frequent relapses. The recognition of this uncommon phenotype in multiple sclerosis is important as the treatment is largely different from other demyelinating diseases. We describe a patient with highly active relapsing-remitting multiple sclerosis on interferon beta-1a who developed LETM after multiple relapses.

Fulltext Chemotherapy-induced transverse melanonychia

Ng CF, Tan HJ, Remli R

BMJ Case Rep, 2021 Aug 17;14(8).

PMID: 34404676 DOI: 10.1136/bcr-2021-245878

Fulltext Stroke care in Pusat Perubatan UKM; the actual picture

Sahathevan R, Wan Yahya WNN, Tan HJ, Mohd Ibrahim N

Med J Malaysia, 2013 Apr;68(2):187-8.

PMID: 23629577

Fulltext Short QTc in epilepsy patients without cardiac symptoms

Teh HS, Tan HJ, Loo CY, Raymond AA

Med J Malaysia, 2007 Jun;62(2):104-8.

PMID: 18705439

Epilepsy patients have a higher mortality rate than the general population. Sudden unexpected death in epilepsy (SUDEP) is a major cause of mortality for these patients. The possibility of cardiac involvement in the pathogenesis of SUDEP has been suggested by many previous studies. This study compared the QT interval in epilepsy patients and normal controls, and identified the factors that affected the QT interval. Standard 12-lead ECGs were recorded from 70 consecutive epilepsy patients from the neurology clinic of HUKM and 70 age, race and gender matched controls. The mean QT interval corrected for heart rate (QTc) was calculated and compared. The mean QTc among the epilepsy patients was 0.401 +/- 0.027s. It was significantly shorter than the QTc (0.420 +/- 0.027s) in the control group (p<0.0005). Thirty five epilepsy patients (50%) and 17 matched controls (24.3%) had a mean QTc shorter than 0.40s (p=0.001). Among the epilepsy patients, the mean QTc did not significantly differ between patients in the duration (F=0.836, p=0.438) of the epilepsy, frequency (F=0.273, p=0.845) and types of seizures (p=0.633). There was no significant difference in the mean QTc between the epilepsy patients on different number of antiepileptic agents (F=0.444, p=0.643). Patients with cryptogenic epilepsy had a mean QTc of 0.392 +/- 0.029s, which was significantly shorter than patients with symptomatic epilepsy (QTc = 0.410 +/- 0.027s, p = 0.015). The mean QTc of the same subjects showed no significant interobserver difference (p=0.661). This study, for the first time, demonstrates that epilepsy patients have a significantly shorter QTc than controls, particularly in the subgroup of patients with cryptogenic epilepsy.
Study site: Neurology clinic, Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia

Fulltext The electroencephalogram changes in migraineurs

Tan HJ, Suganthi C, Dhachayani S, Rizal AM, Raymond AA

Med J Malaysia, 2007 Mar;62(1):56-8.

PMID: 17682573 MyJurnal

Migraine is associated with a variety of electroencephalographic (EEG) changes. Previous studies using analogue EEG and old diagnostic criteria may under or over report the prevalence of EEG changes in migraine. The objective of this study was to reevaluate the EEG changes in migraine patients diagnosed by applying the new International Classification of Headache Disorder -2 criteria. This was a case control study involving 70 migraine patients and 70 age and gender matched control who were subjected to scalp EEG. The EEG changes during hyperventilation (HV), which were significantly more common in the migraine group were theta activity (34 vs 22, p = 0.038) and frontal intermittent rhythmic delta activity (FIRDA) (10 vs 3, p = 0.042). Applying the new ICHD -2 diagnostic criteria and digital EEG, this study yielded previously unrecognized features including FIRDA during HV on EEG.

Role of Helicobacter pylori virulence factor and genotypes in non-ulcer dyspepsia

Tan HJ, Rizal AM, Rosmadi MY, Goh KL

J Gastroenterol Hepatol, 2006 Jan;21(1 Pt 1):110-5.

PMID: 16706821

The role of Helicobacter pylori (HP) in non-ulcer dyspepsia is debatable. Eradicating HP will help a small group of non-ulcer dyspeptic patients. However, it is unclear which subgroup of patients will benefit from eradication therapy. The aim of the present study was to compare the cagA and cagE status, as well as vacA genotypes, of HP in non-ulcer dyspeptic patients who responded successfully to eradication therapy compared with those patients who did not.

Distribution of Helicobacter pylori cagA, cagE and vacA in different ethnic groups in Kuala Lumpur, Malaysia

Tan HJ, Rizal AM, Rosmadi MY, Goh KL

J Gastroenterol Hepatol, 2005 Apr;20(4):589-94.

PMID: 15836708

There is a geographic variation in Helicobacter pylori (HP) genotypes and virulence factors. Cytotoxin associated genes A (cagA) and E (cagE), and certain vacuolating cytotoxin (vacA) genotypes are associated with peptic ulcer disease (PUD). There is also a different prevalence of PUD among different ethnic groups in Malaysia. The present study compared the distribution of vacA alleles and cagA and cagE status in three ethnic groups residing in Kuala Lumpur, Malaysia, and their association with clinical outcome.

Fulltext A Treatable Encephalopathy in a Peritoneal Dialysis Patient - Cefepime-Induced Encephalopathy

Khoo CS, Tee TY, Tan HJ, Ali RA

J Neurosci Rural Pract, 2019 4 20;10(2):324-326.

PMID: 31001027 DOI: 10.4103/jnrp.jnrp_315_18

We report a patient with end-stage renal disease on peritoneal dialysis, who developed encephalopathy after receiving a few doses of cefepime. He recovered clinically and electroencephalographically after having discontinued the culprit agent and undergone hemodialysis. This case highlights the importance of promptly recognizing this reversible encephalopathy, which can lead to the avoidance of unnecessary workup, reduce the length of hospital stay, and thereby improve the patients' outcome.

Silent microaspirations: The forerunner to the diagnosis of bulbar onset myasthenia gravis in a young woman

Tan TL, Tan HJ, Cheah CF, Kumaresh R, Azzahra NA

Med J Malaysia, 2020 05;75(3):295-297.

PMID: 32467548

Recurrent pneumonia warrants a diligent work-up to identify the underlying cause that perpetuates the disease process. Insidious bulbar dysfunction is arguably the most devastating as it would be diagnosed late after significant pulmonary complications due to chronic micro-aspiration. Bulbar disorder should be considered as the potential aetiology of recurrent pulmonary infections in the young population after excluding immunodeficiency disorder and respiratory anatomical anomaly. This report illustrates a rare case of bulbar onset myasthenia gravis which manifested as focal bronchiolectasis due to recurrent undiagnosed aspiration pneumonia three years earlier. Absence of hallmark features of Myasthenia Gravis (MG) such as ptosis, opthalmoplegia and proximal muscle weakness contributed to the diagnostic delay and challenges in this case. The diagnosis was established with the collaboration of multidisciplinary teams. Subsequent correct therapeutic interventions resulted in remarkable recovery in functional status and prevented her from further aspiration in the long run.

Oral epigallocatechin gallate reduces intestinal nadolol absorption via modulation of Oatp1a5 and Oct1 transcriptional levels in spontaneously hypertensive rats

Tan HJ, Ling WC, Chua AL, Lee SK

Phytomedicine, 2021 Sep;90:153623.

PMID: 34303263 DOI: 10.1016/j.phymed.2021.153623

BACKGROUND: Concurrent use of epigallocatechin-3-gallate (EGCG) and medication may lead to botanical-drug interactions, subsequently therapeutic failure or drug toxicity. It has been reported that EGCG reduces plasma nadolol bioavailability in normotensive models. Nevertheless, evidence on the effects of EGCG on hypertensive model, and the possible underlying mechanism have not been elucidated.

OBJECTIVES: This study aims (i) to investigate the effects of EGCG on nadolol pharmacokinetics (maximum plasma concentration, time to achieve maximum concentration, area under the time-plasma concentration curve, plasma half-life and total clearance) and subsequently its impact on blood pressure control; and (ii) to identify transcriptional regulatory roles of EGCG on the nadolol intestinal and hepatic drug-transporters in SHR.

METHODS: Male SHR were pre-treated with a daily dose of EGCG (10 mg/kg body weight, i.g.) for 13 days. On day-14, a single dose of nadolol (10 mg/kg body weight) was given to the rats 30 min after the last dose of EGCG administration. Systolic blood pressure (SBP) was measured at 6-h and 22-h post-nadolol administration. Plasma and urinary nadolol concentrations were quantified using high-performance liquid chromatography, and pharmacokinetic parameters were analyzed by using non-compartmental analysis. Hepatic and ileal Oatp1a5, P-gp, and Oct1 mRNA expressions were determined by real-time PCR.

RESULTS: SBP of SHR pre-treated with EGCG and received nadolol was significantly higher than those which were not pre-treated with EGCG but received nadolol. Pre-treatment of EGCG resulted in a marked reduction of plasma nadolol maximum concentration (Cmax) and area under the time-plasma concentration curve (AUC) by 53% and 51% compared to its control. The 14-day treatment with oral EGCG led to a significant downregulation of mRNA levels of ileal Oatp1a5, P-gp, and Oct1 genes by 4.03-, 8.01- and 4.03-fold; and hepatic P-gp, and Oct1 genes by 2.61- and 2.66-fold.

CONCLUSION: These data concluded that exposure to EGCG could lead to reduced nadolol bioavailability and therefore, uncontrolled raised blood pressure and higher risks of cardiovascular events. Our data suggest that the reduced nadolol bioavailability is associated with the downregulation of ileal Oatp1a5 and Oct1 mRNA levels that subsequently lead to poor absorption of nadolol to the systemic circulation.

Displaying publications 1 - 20 of 98 in total