Implementation of genetic screening test to reduce the incidence of dapsone hypersensitivity syndrome among patients with leprosy in Papua, Indonesia: a study protocol.

INTRODUCTION: The mainstay of leprosy treatment is multidrug treatment (MDT), which contains rifampicin, dapsone and clofazimine. The occurrence of dapsone hypersensitivity syndrome (DHS), a sudden, potentially fatal and traumatic adverse reaction due to dapsone, may affect treatment adherence and may result in fatality if untreated. Before MDT administration, screening for HLA-B*13:01 in patients with leprosy can potentially reduce DHS risk. The study aims to assess the effectiveness of using a screening test for HLA-B*13:01 in reducing the incidence of DHS and to evaluate the feasibility of using the quantitative PCR-based screening tool as DHS predictors before dapsone administration using individual patient testing in a referral centralised-lab model. METHODS AND ANALYSIS: A total of 310 newly diagnosed patients with leprosy will be recruited from health centres in two highly endemic districts in Indonesia. Dried blood will be taken on filter paper as the specimen receptacle to collect DNA from the patients and transported at room temperature to the leprosy referral laboratory before MDT administration. Checking for HLA-B*13:01 from human DNA is performed using the Nala PGx 1301 V.1 kit. The results will be shared with the leprosy health workers on the site via phone call and courier. Patients with a positive test result will be treated with MDT without dapsone, and patients with a negative result will be treated with complete MDT. Physical examination (weight, height, skin, muscle and nerve function examination), complete blood tests (including renal function test) will be carried out at baseline. Follow-up will be performed at the fourth and eighth weeks to observe any development of adverse drug reactions. ETHICS AND DISSEMINATION: The ethical approval for the study was issued by the Ethical Committee of the National Institute of Health Research and Development, Ministry of Health, Indonesia. Written informed consent will be sought from all participants.

Validation study of HLA-B*13:01 as a biomarker of dapsone hypersensitivity syndrome in leprosy patients in Indonesia.

Leprosy is a stigmatizing, chronic infection which degenerates the nervous system and often leads to incapacitation. Multi-drug therapy which consists of dapsone, rifampicin and clofazimine has been effective to combat this disease. In Indonesia, especially in Papua Island, leprosy is still a problem. Furthermore, there had been higher reports of Dapsone Hypersensitivity Syndrome (DHS) which also challenges leprosy elimination in certain aspects. Globally, DHS has a prevalence rate of 1.4% and a fatality rate up to 13%. The aim of this study is to validate HLA-B*13:01, a previously discovered biomarker for DHS in the Chinese population, as a biomarker for DHS in the Papua population.This is a case-control study of 34 leprosy patients who presented themselves with DHS (case subjects) and 52 leprosy patients without DHS (control subjects). Patients were recruited from 2 provinces: Papua and West Papua. DNA was extracted from 3 ml blood specimens. HLA-B alleles were typed using the gold-standard sequence based typing method. Results were then analysed using logistic regression and risk assessment was carried out. The results of HLA-typing showed that HLA-B*13:01 was the most significant allele associated with DHS, with odds ratio = 233.64 and P-value = 7.11×10-9, confirming the strong association of HLA-B*13:01 to DHS in the Papua population. The sensitivity of this biomarker is 91.2% and specificity is 96.2%, with an area under the curve of 0.95. HLA-B*13:01 is validated as a biomarker for DHS in leprosy patients in Papua, Indonesia, and can potentially be a good predictor of DHS to help prevent this condition in the future.

A Review on Dapsone Hypersensitivity Syndrome Among Chinese Patients with an Emphasis on Preventing Adverse Drug Reactions with Genetic Testing.

AbstractDapsone is a bactericidal and bacteriostatic against Mycobacterium leprae, a causative agent of leprosy. Dapsone is also applied in a range of medical fields because of its anti-inflammatory and immunomodulatory effects. Dapsone hypersensitivity syndrome (DHS) is a rare yet serious adverse drug reaction (ADR) caused by dapsone involving multiple organs. We performed a systematic review of published articles describing dapsone-induced hypersensitivity syndrome, including all Chinese articles and the latest literature available in online databases published between October 2009 and October 2015. We determined the prevalence, clinical characteristics, and mortality rate of DHS. Importantly, we also summarized the recent advances in genetic testing allowing prediction of ADRs. In an initial systematic electronic search, we retrieved 191 articles. Subsequently, these articles were further filtered and ultimately 84 articles (60 Chinese case reports, 21 non-Chinese articles, and three epidemiological studies) were selected, which included 877 patients. The prevalence of DHS among Chinese patients was 1.5% with a fatality rate of 9.6%. Early withdrawal of dapsone and appropriate treatment reduced the fatality rate. Most importantly, genetic screening for the HLA-B*13:01 allele among high-risk populations showed a significant utility as a useful genetic marker to DHS. In conclusion, this review discusses the epidemiological and clinical characteristics of DHS among Chinese patients, which may help physicians to understand this syndrome.

Drug reaction with eosinophilia and systemic symptoms (DRESS): A histopathology based analysis.

BACKGROUND: The data on the histology of cutaneous lesions of drug reaction with eosinophilia and systemic symptoms (DRESS) is limited. AIMS: To study the histopathology of cutaneous lesions of drug reaction with eosinophilia and systemic symptoms (DRESS) and to identify any features with diagnostic or prognostic significance. METHODS: All patients admitted to the dermatology ward of government medical college, Kozhikode from January 1, 2014 to December 31, 2014 with probable or definite DRESS as per the RegiSCAR scoring system and who were willing to undergo skin biopsy were included in this prospective study. RESULTS: The study population comprised of nine patients. The consistent histological finding documented was the predominantly lymphocytic dermal inflammatory infiltrate. Four of the five patients whose histology revealed focal interface dermatitis and keratinocyte vacuolation with or without apoptotic keratinocytes, had elevated liver transaminases. Tissue eosinophilia was associated with disease flares. The presence of atypical lymphocytes in peripheral smear and histological evidence of dense dermal inflammatory infiltrate showed an association with hepatic involvement. LIMITATIONS: The main limitations of our study were the small sample size and our inability to carry out a detailed immunohistochemistry work-up. CONCLUSIONS: In the appropriate setting, varying combinations of epidermal hyperplasia, spongiosis, parakeratosis and individually necrotic keratinocytes in the background of lymphocyte predominant dermal infiltrate (with some atypia) favor a diagnosis of drug reaction with eosinophilia and systemic symptoms. Female sex, the presence of atypical lymphocytes in peripheral smear, dense dermal inflammatory infiltrate, tissue eosinophilia and interface dermatitis with or without keratinocyte necrosis was associated with a poor prognosis.

Drug hypersensitivity syndrome.

Drug hypersensitivity syndrome (DHS) is an adverse drug reaction commonly associated with the aromatic antiepileptic drugs (AEDs), viz., phenytoin (PHT), carbamazepine (CBZ), phenobarbital (PB), lamotrigine, primidone, etc. It can also be caused by other drugs, such as sulfonamides, dapsone, minocycline, gold derivatives, cyclosporine, captopril, diltiazem, terbinafine, azathioprine and allopurinol. Diagnosis of DHS may be difficult because of the variety of clinical and laboratory abnormalities and manifestations and because the syndrome may mimic infectious, neoplastic or collagen vascular disorders. The risk for developing hypersensitivity within 60 days of the first or second prescription in new users of PHT or CBZ was estimated to be 2.3-4.5 per 10,000 and 1-4.1 per 10,000, respectively. The syndrome is defined by the fever, skin rash, lymphadenopathy and internal organ involvement within the first 2-8 weeks after initiation of therapy. Internal manifestations include, among others, agranulocytosis, hepatitis, nephritis and myositis. Insufficient detoxification may lead to cell death or contribute to the formation of antigen that triggers an immune reaction. Cross-reactivity among PHT, CBZ and PB is as high as 70%-80%. Management mainly includes immediate withdrawal of the culprit drug, symptomatic treatment and systemic steroids or immunoglobulins.

Dapsone hypersensitivity syndrome in non-leprosy patients: a retrospective study of its incidence in a tertiary referral center in Taiwan.

BACKGROUND: Dapsone hypersensitivity syndrome (DHS) is a potentially life-threatening adverse drug reaction consisting of fever, hepatitis, exfoliative dermatitis, lymphadenopathy and hemolytic anemia. The incidence of DHS is estimated to be 2% in leprosy patients. Because the incidence of this drug eruption may be different in different ethnicities and diseases, we thought to investigate the incidence of DHS in non-leprosy patients. METHODS: This is a retrospective study to examine the incidence, clinical manifestations and prognosis of DHS in non-leprosy patients who were given dapsone at the National Taiwan University Hospital between June 2001 and December 2005. RESULTS: The incidence of DHS among non-leprosy patients was 1.66%. These patients ran a relatively benign course as compared with leprosy patients. CONCLUSION: The incidence of DHS among non-leprosy patients was compatible to that observed among leprosy patients. DHS in non-leprosy patients runs a favorable course with low morbidity in our study.

Mortality due to dapsone hypersensitivity syndrome complicating multi-drug therapy for leprosy in Nepal.

Dapsone is a component of multi-drug therapy (MDT) for the treatment of all types of leprosy. It is known that dapsone hypersensitivity syndrome (DHS) complicates the treatment in a proportion of patients. We performed a retrospective study of patients commenced on MDT between 1990 and 2006; 2% developed DHS and 0.25% died due to DHS.

Increase in the incidence of dapsone hypersensitivity syndrome--an appraisal.

There has been an increase in the reports of dapsone hypersensitivity syndrome (DHS) in the past few years, coinciding with the introduction of multidrug therapy (MDT) for leprosy world-wide. The exact cause of this phenomenon is not clear. We report four cases of DHS observed among 252 leprosy patients on MDT and one case of DHS in a patient taking dapsone for nodulocystic acne in the Dermatology Department of the Osmania General Hospital, Hyderabad, India, between June 1997 and January 1999 with few unusual features. In two of these five patients maculopapular rash was severe and progressed to erythroderma. Introduction of MDT in 1982 has not only decreased the prevalence of leprosy but also brought about a positive change in the attitude of people which increased the voluntary reporting of leprosy patients. This, coupled with improvements in organization of leprosy control and awareness among medical personnel of DHS, are probably the most important reasons for the increased reporting of DHS in recent years.

Increased incidence in leprosy of hypersensitivity reactions to dapsone after introduction of multidrug therapy.

In order to address the question whether hypersensitivity reactions to dapsone are becoming more frequent, the clinical data of 7300 leprosy patients treated between 1949 and September 1988 at the McKean Rehabilitation Centre in Thailand were reviewed. Information from the period 1949 to 1969 was too incomplete to allow conclusions. The incidence of hypersensitivity reactions to dapsone between 1970 and 1982 was 0.3%. From 1982 (with the introduction of multidrug therapy) to September 1988, the incidence was 3.6%; a tenfold increase compared with the previous period. Of the 19 cases seen since 1982, 12 were diagnosed as Dapsone syndrome. Of a total of 13 patients seen since 1980 with Dapsone syndrome, 3 ended fatally, indicating the severity of the complication. The question is raised whether an unexplained drug interaction with rifampicin is responsible for the increase of hypersensitivity reactions to dapsone in patients treated for leprosy.