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

Lack of Suspicion of Dapsone Hypersensitivity Syndrome in a Leprosy Patient: Case Report with Fatal Outcome

Background

Dapsone is an antibiotic used in the management of leprosy. Following the worldwide adoption of the dapsone-containing multidrug therapy for treating leprosy, an upsurge in the reported frequency of dapsone hypersensitivity syndrome (DHS) has been observed. DHS is associated with a high fatality rate among patients from low-resourced settings and patients with syndrome-associated hepatitis.

Case Presentation

This is a case of a Ghanaian male who, while being treated for leprosy with the multidrug therapy, developed exfoliative dermatitis and signs of liver damage, 6 weeks after treatment initiation. He was managed for dapsone-related exfoliative dermatitis and infectious causes of liver damage were investigated. However, the patient's condition rapidly deteriorated with a fatal outcome despite discontinuation of dapsone. DHS was only considered as a differential diagnosis postmortem.

Conclusion

This case highlights the importance of having a high index of suspicion for DHS in all patients on dapsone and the need for a thorough workup for all leprosy patients who present with exfoliative dermatitis and signs of liver involvement within the latency period of the syndrome, especially in low resource settings. Furthermore, it stresses the need for prompt and appropriate treatment as DHS can quickly become fatal in such settings.

Functional and structural characteristics of HLA-B*13:01-mediated specific T cells reaction in dapsone-induced drug hypersensitivity

BACKGROUND

Severe cutaneous adverse drug reactions (SCARs) are a group of serious clinical conditions caused by immune reaction to certain drugs. The allelic variance of human leukocyte antigens of HLA-B*13:01 has been strongly associated with hypersensitivities induced by dapsone (DDS). T-cell receptor mediated activation of cytotoxic T lymphocytes (CTLs) has also been suggested to play an essential role in pathogenesis of SCARs. However, HLA-B*13:01-DDS-TCR immune synapse that plays role in drug-induced hypersensitivity syndrome (DIHS) associated T cells activation remains uncharacterized.

METHODS

To investigate the molecular mechanisms for HLA-B*13:01 in the pathogenesis of Dapsone-induced drug hypersensitivity (DDS-DIHS), we performed crystallization and expanded drug-specific CTLs to analyze the pathological role of DDS-DIHS.

RESULTS

Results showed the crystal structure of HLA-B*13:01-beta-2-microglobulin (β2M) complex at 1.5 Å resolution and performed mutation assays demonstrating that I118 or I119, and R121 of HLA-B*13:01 were the key residues that mediate the binding of DDS. Subsequent single-cell TCR and RNA sequencing indicated that TCRs composed of paired TRAV12-3/TRBV28 clonotype with shared CDR3 region specifically recognize HLA-B*13:01-DDS complex to trigger inflammatory cytokines associated with DDS-DIHS.

CONCLUSION

Our study identified the novel p-i-HLA/TCR as the model of interaction between HLA-B*13:01, DDS and the clonotype-specific TCR in DDS-DIHS.

Novel approaches in the treatment of Hansen's disease (Leprosy): a case series of multidrug therapy of monthly rifampin, moxifloxacin, and minocycline (RMM) in the United States

The World Health Organization (WHO) recommends multidrug therapy (MDT) for the treatment of paucibacillary and multibacillary forms of leprosy, also known as Hansen's disease (HD). MDT combinations of dapsone, rifampin, and clofazimine have reduced the prevalence of the disease but are not without adverse effects impacting regimen adherence. Hence, an urgent need exists to consider alternative MDT regimens with an improved safety profile that promotes treatment adherence. Herein, we described a case series of 10 patients with HD (nine patients with multibacillary leprosy and one with pure neural leprosy) treated with monthly rifampin, moxifloxacin, and minocycline (RMM). The United States National Hansen's Disease Program (NHDP) diagnosed and treated patients across US institutions. All patients received a regimen of 12-24 months of RMM. We reviewed the clinical outcomes, adherence, rate of completion, and adverse events of patients treated with monthly RMM from January 2019 to August 2022. Nine patients had multibacillary leprosy, with some having type-2 reactions. One patient had pure neural leprosy with a reversal reaction. In this case series, we identified that all patients completed the RMM regimen without treatment interruptions. None of the patients experienced any skin hyperpigmentation or any significant side effects. All patients tolerated the monthly RMM regimen with rapid improvement of skin lesions and without logistic hurdles. Based on previous clinical evidence and the results of this case series, the NHDP and other programs should consider the RMM regimen as first-line therapy.

HLA-B*13 :01 Is a Predictive Marker of Dapsone-Induced Severe Cutaneous Adverse Reactions in Thai Patients

HLA-B*13:01 allele has been identified as the genetic determinant of dapsone hypersensitivity syndrome (DHS) among leprosy and non-leprosy patients in several studies. Dapsone hydroxylamine (DDS-NHOH), an active metabolite of dapsone, has been believed to be responsible for DHS. However, studies have not highlighted the importance of other genetic polymorphisms in dapsone-induced severe cutaneous adverse reactions (SCAR). We investigated the association of HLA alleles and cytochrome P450 (CYP) alleles with dapsone-induced SCAR in Thai non-leprosy patients. A prospective cohort study, 16 Thai patients of dapsone-induced SCARs (5 SJS-TEN and 11 DRESS) and 9 Taiwanese patients of dapsone-induced SCARs (2 SJS-TEN and 7 DRESS), 40 dapsone-tolerant controls, and 470 general Thai population were enrolled. HLA class I and II alleles were genotyped using polymerase chain reaction-sequence specific oligonucleotides (PCR-SSOs). CYP2C9, CYP2C19, and CYP3A4 genotypes were determined by the TaqMan real-time PCR assay. We performed computational analyses of dapsone and DDS-NHOH interacting with HLA-B*13:01 and HLA-B*13:02 alleles by the molecular docking approach. Among all the HLA alleles, only HLA-B*13:01 allele was found to be significantly associated with dapsone-induced SCARs (OR = 39.00, 95% CI = 7.67–198.21, p = 5.3447 × 10⁻⁷), SJS-TEN (OR = 36.00, 95% CI = 3.19–405.89, p = 2.1657 × 10⁻³), and DRESS (OR = 40.50, 95% CI = 6.38–257.03, p = 1.0784 × 10⁻⁵) as compared to dapsone-tolerant controls. Also, HLA-B*13:01 allele was strongly associated with dapsone-induced SCARs in Asians (OR = 36.00, 95% CI = 8.67–149.52, p = 2.8068 × 10⁻⁷) and Taiwanese (OR = 31.50, 95% CI = 4.80–206.56, p = 2.5519 × 10⁻³). Furthermore, dapsone and DDS-NHOH fit within the extra-deep sub pocket of the antigen-binding site of the HLA-B*13:01 allele and change the antigen-recognition site. However, there was no significant association between genetic polymorphism of cytochrome P450 (CYP2C9, CYP2C19, and CYP3A4) and dapsone-induced SCARs (SJS-TEN and DRESS). The results of this study support the specific genotyping of the HLA-B*13:01 allele to avoid dapsone-induced SCARs including SJS-TEN and DRESS before initiating dapsone therapy in the Asian population.

Bibliometric analysis of adverse drug reactions and pharmacovigilance research activities in Nepal

Background:

Bibliometric analyses have been used previously to study the measures of quality and impact of research performed in several health-related areas such as adverse drug reactions (ADRs) and pharmacovigilance (PV), etc. This method can assess the research performance of publications quantitatively and statistically. There is no evidence of bibilometric studies analyzing ADRs and PV from Nepal. Therefore, the present study aimed to assess scientific output on ADRs and PV-related research activities in Nepal using a bibliometric analysis of publications from 2004 January to December 2018, that is, 15 years.

Methods:

A systematic search was conducted in PubMed, Web of Science, Google Scholar, Scopus and Nepal Journal Online (NepJOL) databases. ‘Adverse Drug Reactions‘ or ‘ADRs‘ or ‘ADR‘ or ‘Adverse drug reaction‘ or ‘AE‘ or ‘Adverse Event‘ or ‘Drug-Induced Reaction‘ or ‘Pharmacovigilance‘ or ‘PV‘ and ‘Nepal‘. The search covered 15 years (January 2004 to December 2018) of study on ADRs and PV in Nepal. Only articles retrieved from databases were included, whereas published/unpublished drug bulletins, pharmacy newsletters and thesis were excluded. The articles thus retrieved were recorded, and thereafter analyzed. Word count code was used for the analysis of keywords used in the retrieved articles.

Results:

A total of 124 articles were retrieved, with the highest rate of publications in 2006 and 2007, with 16 papers each. Among the articles, 10 (8.1%) were published in Kathmandu University Medical Journal (KUMJ). Single papers were published in 38 different journals. Brief reports (1.6%), case reports (31.2%), case series (0.8%), education forums (0.8%), letters to the editor (5.6%), original research articles (41.9%), review articles (9.7%), short communications and short reports (8.1%) on ADRs and PV were recorded. Out of 124 papers, 52 (41.9%) were original research publications. The majority (74.1%) of research was done in the category of ADR incidence, types, prevention, and management, followed by policy and suggestions for strengthening national and regional pharmacovigilance centers of Nepal (14.5%).

Conclusions:

During the study years, there was an increase in scientific publications on drug safety. A total of 124 published articles were found during bibliometric analysis of ADRs and PV research activities in Nepal.

Evaluation of Prospective HLA-B*13:01 Screening to Prevent Dapsone Hypersensitivity Syndrome in Patients With Leprosy

Importance

Dapsone hypersensitivity syndrome (DHS) is the most serious adverse reaction associated with dapsone administration and one of the major causes of death in patients with leprosy, whose standard treatment includes multidrug therapy (MDT) with dapsone, rifampicin, and clofazimine. Although the HLA-B*13:01 polymorphism has been identified as the genetic determinant of DHS in the Chinese population, no studies to date have been done to evaluate whether prospective HLA-B*13:01 screening could prevent DHS by identifying patients who should not receive dapsone.

Objective

To evaluate the clinical use of prospective HLA-B*13:01 screening for reduction of the incidence of DHS by excluding dapsone from the treatment for patients with HLA-B*13:01-positive leprosy.

Design, Setting, and Participants

A prospective cohort study was conducted from February 15, 2015, to April 30, 2018, in 21 provinces throughout China. A total of 1539 patients with newly diagnosed leprosy were enrolled who had not received dapsone previously. After excluding patients who had a history of allergy to sulfones or glucose-6-phosphate dehydrogenase deficiency, 1512 individuals underwent HLA-B*13:01 genotyping. All of the patients were followed up weekly for the first 8 weeks after treatment to monitor for adverse events.

Exposures

Patients who were HLA-B*13:01 carriers were instructed to eliminate dapsone from their treatment regimens, and noncarrier patients received standard MDT.

Main Outcomes and Measures

The primary outcome was the incidence of DHS. The historical incidence rate of DHS (1.0%) was used as a control.

Results

Among 1512 patients (1026 [67.9%] men, 486 [32.1%] women; mean [SD] age, 43.1 [16.2] years), 261 (17.3%) were identified as carriers of the HLA-B*13:01 allele. A total of 714 adverse events in 384 patients were observed during the follow-up period. Dapsone hypersensitivity syndrome did not develop in any of the 1251 patients who were HLA-B*13:01-negative who received dapsone, while approximately 13 patients would be expected to experience DHS, based on the historical incidence rate of 1.0% per year (P = 2.05 × 10-5). No significant correlation was found between other adverse events, including dermatologic or other events, and HLA-B*13:01 status.

Conclusions and Relevance

Prospective HLA-B*13:01 screening and subsequent elimination of dapsone from MDT for patients with HLA-B*13:01-positive leprosy may significantly reduce the incidence of DHS in the Chinese population.

Association Between HLA-B*1301 and Dapsone-Induced Cutaneous Adverse Drug Reactions: A Systematic Review and Meta-analysis

Importance

Dapsone-induced hypersensitivity syndrome (DHS) is a life-threatening adverse drug reaction. Based on available epidemiologic studies, HLA genotypes may play an important role in DHS.

Objective

To assess the association between HLA-B*1301 and dapsone-induced cutaneous adverse drug reactions (cADRs).

Data Sources

Human studies investigating associations between HLA-B*1301 and dapsone-induced cADRs were systematically searched without language restriction from the inception of each database until September 12, 2017, in PubMed, the Human Genome Epidemiology Network), and the Cochrane Library. Combinations of HLA genotypes, dapsone, and synonymous terms were used; reference lists were searched in selected articles.

Study Selection

Two reviewers identified studies investigating the associations between HLA-B*1301 and dapsone-induced cADRs that reported sufficient data for calculating the frequency of HLA-B*1301 carriers among case and control patients, in which all patients received dapsone before HLA-B*1301 screening. An initial search of the databases identified 391 articles, of which 3 studies (2 in Chinese populations and 1 in a Thai population) met the inclusion criteria.

Data Extraction and Synthesis

Overall odds ratios (ORs) with 95% CIs were calculated using a random-effects model to determine the association between HLA-B*1301 and dapsone-induced cADRs. Subgroup analyses by type of cADR were also performed. PRISMA guidelines were used to abstract and assess data.

Main Outcomes and Measures

Primary outcomes were associations between HLA-B*1301 and dapsone-induced cADRs in dapsone-tolerant controls. The outcomes are reported as overall OR. Statistical heterogeneity was assessed using the Q statistic and I2 tests.

Results

From the 3 included studies, there were 111 unique patients with dapsone-induced cADRs (subsequently used in the meta-analysis), 1165 dapsone-tolerant patients, and 3026 healthy controls. The cases included 64 men and 49 women (2 patients were missing from the meta-analysis; 1 each from 2 of the 3 studies); mean age was 39.7 years. An association between HLA-B*1301 and dapsone-induced cADRs was identified (summary OR, 43.0; 95% CI, 24.0-77.2). Subgroup analyses among types of cADRs produced similar findings in DHS (OR, 51.7; 95% CI, 16.9-158.5), dapsone-induced severe cADRs (Stevens-Johnson syndrome and toxic epidermal necrolysis [SJS/TEN] plus drug rash [adverse skin reaction to a drug] along with eosinophilia and systemic symptoms [DRESS]) (OR, 54.0; 95% Cl, 8.0-366.2), dapsone-induced SJS/TEN (OR, 40.5; 95% CI, 2.8-591.0), and dapsone-induced DRESS (OR, 60.8; 95% CI, 7.4-496.2). There was no heterogeneity (I2 = 0%, P = .38).

Conclusions and Relevance

Associations between HLA-B*1301 and dapsone-induced cADRs were found in dapsone-tolerant and healthy control groups. For patient safety, genetic screening for HLA-B*1301 in Asian populations before dapsone therapy is warranted.

Th17 Response of Borderline-Lepromatous Leprosy Inhibits Rash Manifestation of Dapsone Hypersensitivity Syndrome: Case Report

BACKGROUND

Dapsone hypersensitivity syndrome (DHS) is a rare, but potentially life-threatening reaction to dapsone.

OBJECTIVE

Evaluation of immunological factors involved in the sparing of borderline-lepromatous (BL) leprosy patches by the severe exanthema related to DHS.

METHODS

The authors describe a 19-year-old man with borderline-lepromatous leprosy with a recent diffuse rash, sparing only the hypochromic patches of leprosy, generalized lymphadenopathy, hepatomegaly, and jaundice 25 days after the start of multibacillary multidrug therapy.

RESULTS

Laboratory testing was remarkable for leukocytosis with eosinophilia, atypical lymphocytosis, and elevated liver and canalicular enzymes. Immunohistopathology of the rash showed stronger expression of Th1 cytokines (IL1β, TNFα, IFNγ, and iNOS), and limited expression of IL17, TGFb, IL4, and IL10. Whereas the hypochromic leprosy patches showed high expression of inflammatory cytokines IL1β, TNFα, IFNγ, iNOS, and TGFβ (Th1), and presented strong expression of IL17 and TGFβ with no IL4 and IL10 expression, by the inflammatory infiltrate, characterizing a participation of Th17 response.

CONCLUSION

Th17 response, coupled with the presence of subepidermal collagen band, seems to be directly related to the absence of DHS rash in these hypochromic leprosy patches.

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.

Dapsone hypersensitivity syndrome: A rare life threatening complication of dapsone therapy

Dapsone can cause several adverse effects, the most serious being dapsone hypersensitivity syndrome (DHS), which is potentially fatal. Here we report a case of severe, life threatening dapsone systemic hypersensitivity syndrome in a 17-year-old male who presented with high grade fever, eosinophilia, lymphadenopathy, skin rash, hepatitis and encephalopathy, which was managed successfully with oral steroids. The case is being reported to emphasize the need for timely diagnosis and prompt treatment of this rare complication for successful outcomes. DHS is also reviewed in brief.

Dapsone hypersensitivity syndrome causing disseminated intravascular coagulation

Dapsone hypersensitivity syndrome is an idiosyncratic reaction to this drug and can present with different clinical manifestations of varying severity. We describe a patient with disseminated intravascular coagulation (DIC) as an adverse reaction to dapsone. To the best of our knowledge, this is the first time it has been described in the literature. She presented with fever, rash and abdominal pain; she also had marked eosinophilia and features suggestive of oxidative haemolysis. Her course was complicated by DIC, splenic infarction and gastrointestinal bleeding. Extensive investigations did not reveal any alternative aetiology. She was initially treated with supportive measures and folic acid; steroids were administered later, following clinical deterioration. There was gradual improvement and the steroids were tapered. The patient recovered fully and remains well; her underlying chronic dermatologic condition is under satisfactory control with other medications.