Allopurinol is the well-known first-line treatment option for symptomatic hyperuricaemia and gout. It is cost-effective particularly for the management of chronic gout. The common early side effects of allopurinol are skin rashes, diarrhoea and nausea. Meanwhile, a dangerous concerning complication is Stevens–Johnson syndrome, which can cause severe morbidity and mortality. Delayed hypersensitivity to allopurinol is rare but should be one of the differential diagnoses if a patient with underlying gout on chronic allopurinol treatment presents with skin rashes. The present case highlights the importance of a high index of suspicion in at-risk patients with underlying gout along with skin rashes on long-term allopurinol treatment to avoid unnecessary patient management.
Hypersensitivity, Delayed ; Allopurinol ; Exanthema

Background: One of the causes of inflammatory arthritis is excessive production of uric acid or hyperuricemia. It is a painful disease that is treated with a commercial xanthine oxidase inhibitor to decrease uric acid synthesis. However, the treatment is associated with adverse side effects and thus, there is interest in medicinal plants that could have similar therapeutic effects with minimal side effects. There are many reported indigenous plants and trees in the Philippines that are reported to have therapeutic and bioactive compounds. One such plant is Canarium ovatum or locally called pili. This study aimed to determine the antihyperuricemic activity of the ethanolic extract of the leaves of C. ovatum. Objective: Determine the antihyperuricemic activity of the crude ethanolic extract of C. ovatum leaves and its partially purified fractions through inhibition of xanthine oxidase and its effect on the blood uric acid level of oxonate-induced hyperuricemic mice. Methodology: The crude ethanol extract from C. ovatum leaves and its partially purified fractions obtained through column chromatography were tested for their in vitro xanthine oxidase (XO) inhibitory activity by measuring spectrophotometrically the uric acid formation from xanthine as the substrate. The crude ethanol extract and the fraction with the most XO inhibitory activity were then tested for their in vivo XO inhibitory activity in oxonate-induced hyperuricemic mice by measuring their blood uric acid levels using uric acid test strips. Results: The crude ethanolic extract of C. ovatum leaves at 100ppm showed 83.62±2.05% in vitro inhibition of XO while the most active fraction showed 80.30±4.00% inhibition. Both were comparable (p>0.05) to the positive control, allopurinol, which showed 91.47±5.64% inhibition. In vivo, the crude extract and the fraction that showed the highest XO inhibitory activity at 200 mg/kg significantly (p<0.01 and p<0.05) respectively reduced the serum uric acid levels of the hyperuricemic mice one hour after induction as compared to the negative control. Moreover, their antihyperuricemic activity were not statistically significant as compared to that of allopurinol (p<0.0001). Conclusion The crude ethanolic extract of C. ovatum leaves and its most active fraction showed statistically significant in vitro xanthine oxidase inhibition and in vivo antihyperuricemic activity. The activities shown by both crude and active fraction were not statistically different from that determined for allopurinol. Therefore, further studies can be conducted to isolate the most active compound and study its pharmacokinetic properties.
Xanthine Oxidase ; Uric Acid ; Allopurinol

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions. Although viral reactivation is associated with DRESS syndrome, its role in TEN remains unclear. An 80-year-old woman visited our hospital because of fever and skin eruption. DRESS syndrome was diagnosed and was thought to caused by the use of the drug allopurinol. She was treated by discontinuation of the drug and administration of systemic steroids. She recovered from DRESS syndrome and was discharged from the hospital with tapering doses of steroids prescribed. One week after discharge, she visited our hospital again as the skin rash recurred and oral pain as well as oral and ocular mucosal lesions developed. In addition to the skin rash, blisters and Nikolsky's sign that were different from the skin lesions present in the previous DRESS syndrome were observed. Unlike those in DRESS syndrome, the viral serological test results were positive for anti-cytomegalovirus (CMV) IgM and CMV polymerase chain reaction. Therefore, it was thought that TEN was due to reactivation of CMV and she was treated this with ganciclovir and intravenous immunoglobulin. Here, we report a case of TEN caused by viral reactivation after DRESS syndrome developed after use of allopurinol which recovered after steroid treatment.
Aged, 80 and over ; Allopurinol ; Blister ; Cytomegalovirus Infections ; Cytomegalovirus ; Drug Hypersensitivity Syndrome ; Eosinophilia ; Exanthema ; Female ; Fever ; Ganciclovir ; Humans ; Immunoglobulin M ; Immunoglobulins ; Polymerase Chain Reaction ; Serologic Tests ; Skin ; Steroids ; Stevens-Johnson Syndrome

There are geographical, regional, and ethnic differences in the phenotypes and endotypes of patients with drug hypersensitivity reactions (DHRs) in different parts of the world. In Asia, aspects of drug hypersensitivity of regional importance include IgE-mediated allergies and T-cell-mediated reactions, including severe cutaneous adverse reactions (SCARs), to beta-lactam antibiotics, antituberculous drugs, nonsteroidal anti-inflammatory drugs (NSAIDs) and radiocontrast agents. Delabeling of low-risk penicillin allergy using direct oral provocation tests without skin tests have been found to be useful where the drug plausibility of the index reaction is low. Genetic risk associations of relevance to Asia include human leucocyte antigen (HLA)-B*1502 with carbamazepine SCAR, and HLA-B*5801 with allopurinol SCAR in some Asian ethnic groups. There remains a lack of safe and accurate diagnostic tests for antituberculous drug allergy, other than relatively high-risk desensitization regimes to first-line antituberculous therapy. NSAID hypersensitivity is common among both adults and children in Asia, with regional differences in phenotype especially among adults. Low dose aspirin desensitization is an important therapeutic modality in individuals with cross-reactive NSAID hypersensitivity and coronary artery disease following percutaneous coronary intervention. Skin testing allows patients with radiocontrast media hypersensitivity to confirm the suspected agent and test for alternatives, especially when contrasted scans are needed for future monitoring of disease relapse or progression, especially cancers.
Adult ; Allopurinol ; Anaphylaxis ; Anti-Bacterial Agents ; Asia ; Asian Continental Ancestry Group ; Aspirin ; Asthma ; Carbamazepine ; Child ; Cicatrix ; Contrast Media ; Coronary Artery Disease ; Diagnostic Tests, Routine ; Drug Hypersensitivity ; Ethnic Groups ; Humans ; Hypersensitivity ; Penicillins ; Percutaneous Coronary Intervention ; Phenotype ; Recurrence ; Skin Tests

Drug reaction with eosinophilia and systemic symptoms (DRESS) syndrome is a severe cutaneous adverse reaction involving various internal organs. Flare-ups after recovery from the initial presentation of DRESS are caused by relapse of drug-induced T-cell-mediated reactions. However, the specific underlying mechanism is unclear. Here, we report a case of a 60-year-old man with allopurinol-induced DRESS who suffered recurrent episodes of generalized rash with eosinophilia, which mimicked immune reconstitution inflammatory syndrome. Analysis of immunological profiles revealed that the percentages of T lymphocytes and regulatory T cells in the patient with DRESS were higher than those in healthy controls. In addition, there was a notable change in the subtype of monocytes in the patient with DRESS; the percentage of nonclassical monocytes increased, whereas that of classical monocytes decreased. Upon viral infection, nonclassical monocytes exhibited strong pro-inflammatory properties that skewed the immune response toward a Th2 profile, which was associated with persistent flare-ups of DRESS. Taken together, the results increase our understanding of the pathogenesis of DRESS as they suggest that expansion of nonclassical monocytes and Th2 cells drives disease pathogenesis.
Allopurinol ; Drug Hypersensitivity Syndrome ; Eosinophilia ; Exanthema ; Herpesviridae ; Humans ; Immune Reconstitution Inflammatory Syndrome ; Middle Aged ; Monocytes ; Recurrence ; T-Lymphocytes ; T-Lymphocytes, Regulatory ; Th2 Cells

PURPOSE: Despite morbidities and fatalities, nationwide epidemiologic data for severe cutaneous adverse reactions (SCARs), including Stevens-Johnson syndrome (SJS), toxic epidermal necrolysis (TEN), and drug reaction with eosinophilia and systemic symptoms (DRESS), are not widely available. We aimed to investigate SCAR epidemiology over the last two decades in Korea. MATERIALS AND METHODS: We analyzed individual case safety reports (ICSRs) of SCARs in the Korea Adverse Event Reporting System from 1988 to 2013. Administered drugs, demographic profiles, and causality assessment according to the World Health Organization-Uppsala Monitoring Center system were analyzed. RESULTS: A total of 755 SCAR cases (508 SJS/TEN, 247 DRESS) were reported. The number of SCAR ICSRs has been increasing with increasing ICSRs for overall adverse drug events. Since 2010, the number of SCAR ICSRs has increased up to 100 cases/year. Allopurinol was the most common causative drug (SJS/TEN: 10.2%; DRESS: 11.3%; SCAR ICSRs: 10.6%), followed by carbamazepine (SJS/TEN: 8.7%; DRESS: 9.7%; SCAR ICSRs: 8.6%). Regarding drug groups, antiepileptics (19.5%) and antibiotics for systemic use (12.7%) were common causative drug groups. Twenty SCAR-related deaths were recorded. Antibacterials were the most common causes of deaths (8 cases), followed by antiepileptics (5 cases). The potential risk of SCARs was not specified in the drug information leaflet for 40.2% of drugs causing SJS/TEN and 82.5% causing DRESS syndrome in Korea. CONCLUSION: The number of SCAR ICSRs has increased rapidly with recent active pharmacovigilance programs in Korea. Allopurinol and antiepileptics are the most common individual and categorical causative agents, respectively.
Allopurinol ; Anti-Bacterial Agents ; Anticonvulsants ; Carbamazepine ; Cause of Death ; Cicatrix ; Drug Hypersensitivity Syndrome ; Drug-Related Side Effects and Adverse Reactions ; Epidemiology ; Global Health ; Korea ; Pharmacovigilance ; Stevens-Johnson Syndrome

BACKGROUND: Severe cutaneous adverse reactions (SCAR) to drugs are a crucial public health issue and the use of systemic corticosteroids in SCAR has been controversial. OBJECTIVE: To analyze clinical features, causative drugs, treatment, outcomes, and prognostic factors of SCAR in the case-series of 173 patients, and add more information to the debate of using systemic corticosteroids in SCAR management. METHODS: A retrospective study of 173 SCAR patients diagnosed with drug reaction with eosinophilia and systemic symptoms (DRESS), Stevens-Johnson syndrome (SJS)/toxic epidermal necrolysis (TEN) or acute generalized exanthematous pustulosis (AGEP) at a tertiary care institution in China between January 2014 and December 2017 was conducted. RESULTS: Of 173 patients, allopurinol, carbamazepine, and antibiotics are the most frequently implicated drugs for DRESS (40.4%), SJS/TEN (26.0%), and AGEP (40.0%) respectively. Moreover, there is a strongly negative correlation between early corticosteroids use and the progression (p=0.000) and severity (p=0.01) of skin lesions. However, there is no association between early corticosteroids use and the mortality of SCAR (odds ratio: 1.01, 95% confidence interval: 0.95~1.08). In addition, lymphadenopathy, eosinophilia, and interval from onset to corticosteroids treatment were correlated with SCAR prognosis. CONCLUSION: Prompt short-course systemic corticosteroids use is associated with early-stage skin lesions remission without influencing the disease mortality. Lymphadenopathy and eosinophilia were the independent poor prognostic factors of SCAR.
Acute Generalized Exanthematous Pustulosis ; Adrenal Cortex Hormones ; Allopurinol ; Anti-Bacterial Agents ; Carbamazepine ; China ; Cicatrix ; Drug Hypersensitivity Syndrome ; Eosinophilia ; Humans ; Lymphatic Diseases ; Mortality ; Prognosis ; Public Health ; Retrospective Studies ; Skin ; Stevens-Johnson Syndrome ; Tertiary Healthcare

Drug reaction with eosinophilia and systemic symptoms(DRESS), which occurs 2–8 weeks after taking a medication is a rare and potentially life-threatening drug-induced hypersensitivity reaction, which includes skin eruption, hematologic abnormalities, lymphadenopathy, and internal organ such as liver, lung, kidney involvement. Antiepileptic agents (e.g., carbamazepine, lamotrigine, phenytoin, and phenobarbital) and allopurinol are the most commonly reported causes. However, new antiepileptic agents, such as oxcarbazepine, rarely cause drug reaction with eosinophilia and systemic symptoms. A 11-year-old boy who was administered oxcarbazepine for 34 days developed widespread rashes, facial edema, fever, cough, nasal stuffiness, tonsillitis, and cervical lymphadenopathy. Laboratory test results showed leukocytosis, eosinophilia, thrombocytosis, elevated c-reactive protein, and elevated liver transaminase levels. As we suspected drug reaction with eosinophilia and systemic symptoms, we immediately withdrew oxcarbazepine and commenced corticosteroid therapy. The patient's skin lesions and abnormal laboratory results slowly improved. Before change the antiepileptic agents, we performed human leukocyte antigen (HLA) typing to assess the genetic risk factors of the drug reaction and the result was positive for HLA DRB1*04:03 known to cause severe acute drug hypersensitivity, such as Stevens-Johnson syndrome by oxcarbazepine in Koreans. We have presented the first report of drug reaction with eosinophilia and systemic symptoms associated with oxcarbazepine in a patient with HLA DRB1*04:03. Although DRESS by oxcarazepine is extremely rare and unpredictable, when suspected clinical symptoms occur, it is necessary to interrupt the causative drug rapidly and confirming the patient's HLA typing may help to select a safer alternative drug.
Allopurinol ; Anticonvulsants ; C-Reactive Protein ; Carbamazepine ; Child ; Cough ; Drug Eruptions ; Drug Hypersensitivity ; Drug Hypersensitivity Syndrome* ; Edema ; Eosinophilia ; Exanthema ; Fever ; Histocompatibility Testing ; Humans ; Hypersensitivity ; Kidney ; Leukocytes ; Leukocytosis ; Liver ; Lung ; Lymphatic Diseases ; Male ; Palatine Tonsil ; Phenytoin ; Risk Factors ; Skin ; Stevens-Johnson Syndrome ; Thrombocytosis ; Tonsillitis

Adverse drug reactions can cause considerable discomfort. They can be life-threatening in severe cases, requiring or prolonging hospitalization, impeding proper treatment, and increasing treatment costs considerably. Although the incidence of severe cutaneous adverse reactions (SCARs) is low, they can be serious, have permanent sequelae, or lead to death. A recent pharmacogenomic study confirmed that genetic factors can predispose an individual to SCARs. Genetic markers enable not only elucidation of the pathogenesis of SCARs, but also screening of susceptible subjects. The human leukocyte antigen (HLA) genotypes associated with SCARs include HLA-B*57:01 for abacavir (Caucasians), HLA-B*58:01 for allopurinol (Asians), HLA-B*15:02 (Han Chinese) and HLA-A*31:01 (Europeans and Koreans) for carbamazepine, HLA-B*59:01 for methazolamide (Koreans and Japanese), and HLA-B*13:01 for dapsone (Asians). Therefore, prescreening genetic testing could prevent severe drug hypersensitivity reactions. Large-scale epidemiologic studies are required to demonstrate the usefulness and cost-effectiveness of screening tests because their efficacy is affected by the genetic differences among ethnicities.
Allopurinol ; Carbamazepine ; Cicatrix ; Dapsone ; Drug Hypersensitivity ; Drug Hypersensitivity Syndrome ; Drug-Related Side Effects and Adverse Reactions ; Epidemiologic Studies ; Genetic Markers* ; Genetic Testing ; Genotype ; Health Care Costs ; HLA Antigens ; Hospitalization ; Humans ; Incidence ; Leukocytes ; Mass Screening ; Methazolamide ; Pharmacogenetics ; Stevens-Johnson Syndrome

BACKGROUND/AIMS: Stevens-Johnson syndrome (SJS) and toxic epidermal necrolysis (TEN) are severe cutaneous adverse reactions that frequently result in fatal outcomes. We investigated cases of SJS and TEN in a regional hospital. METHODS: From 2008 to 2014, SJS and TEN cases were enrolled retrospectively by allergy and dermatology specialists, and their clinical features and severity-of-illness score for TEN (SCORTEN) were assessed. RESULTS: During the 7-year study period, 56 SJS and 14 TEN cases were recruited. The majority (71%) were 40-70 years of age (mean age of male and female patients, 55 and 54 years, respectively). Regarding drugs, anticonvulsants (42.8%) were the most frequently causative, followed by carbonic anhydrase inhibitors (20.0%), antimicrobials (15.7%), allopurinol (7.1%), and non-steroidal anti-inflammatory drugs (7.1%). No fatal case of SJS was seen. However, 7 of the 14 patients with TEN died (50%; mean age, 67 years; 1 of 5 [20%] males and 6 of 9 females [66.7%]). The mortality rate was reflected in the SCORTEN values. Vancomycin, allopurinol, methazolamide (two cases each) and megestrol (one case) were the causative drugs in the seven fatal TEN cases. Treatment modality did not affect the likelihood of death due to TEN. CONCLUSIONS: The causative drugs of, and frequency of mortality due to, SJS and TEN should be recognized by physicians. Elderly females with TEN are at high risk of mortality. SCORTEN values reflect the mortality rate of TEN patients. Early recognition and proper management of SJS and TEN may reduce the mortality rate.
Aged ; Allopurinol ; Anticonvulsants ; Carbonic Anhydrase Inhibitors ; Dermatology ; Drug-Related Side Effects and Adverse Reactions ; Fatal Outcome ; Female ; Humans ; Hypersensitivity ; Male ; Megestrol ; Methazolamide ; Mortality ; Retrospective Studies ; Specialization ; Stevens-Johnson Syndrome* ; Vancomycin