DNA methylation of ITGB2 contributes to allopurinol hypersensitivity.

BACKGROUNDS: HLA-B*58:01 allele was strongly associated with allopurinol induced severe cutaneous adverse drug reaction (SCAR). However, HLA-B genotype is not sufficient to predict the occurrence of allopurinol-induced SCAR. OBJECTIVE: To discover DNA methylation markers for allopurinol-induced SCAR which may improve the prediction accuracy of genetic testing. STUDY DESIGN: The study was designed as a retrospective case-control clinical study in multicenter hospitals across Taiwan, Mainland China, Malaysia and Canada. 125 cases of allopurinol-induced SCAR patients and 139 cases of allopurinol tolerant controls were enrolled in this study during 2005 to 2021. RESULTS: The results of genome-wide DNA methylation assay of 62 patients revealed that ITGB2 showed strong discriminative ability of allopurinol-induced SCAR in both HLA-B*58:01 positive and negative patients with AUC value of 0.9364 (95% CI 0.8682-1.000). In validation study, significant hypermethylation of ITGB2 were further validated in allopurinol-induced SCAR patients compared to tolerant controls, especially in those without HLA-B*58:01(AUC value of 0.8814 (95% CI 0.7121-1.000)). Additionally, the methylation levels of 2 sites on ITGB2 were associated with SCAR phenotypes. Combination of HLA-B*58:01 genotyping and ITGB2 methylation status could improve the prediction accuracy of allopurinol-induced SCAR with the AUC value up to 0.9387 (95% CI 0.9089-0.9684), while the AUC value of HLA-B*58:01 genotyping alone was 0.8557 (95% CI 0.8030-0.9083). CONCLUSIONS: Our study uncovers differentially methylated genes between allopurinol-induced SCAR patients and tolerant controls with positive or negative HLA-B*58:01 allele and provides the novel epigenetic marker that improves the prediction accuracy of genetic testing for prevention of allopurinol-induced SCAR.

The Medication Risk of Stevens-Johnson Syndrome and Toxic Epidermal Necrolysis in Asians: The Major Drug Causality and Comparison With the US FDA Label.

Specific ethnic genetic backgrounds are associated with the risk of Stevens-Johnson syndrome / toxic epidermal necrolysis (SJS/TEN) especially in Asians. However, there have been no large cohort, multiple-country epidemiological studies of medication risk related to SJS/TEN in Asian populations. Thus, we analyzed the registration databases from multiple Asian countries who were treated during 1998-2017. A total 1,028 SJS/TEN cases were identified with the algorithm of drug causality for epidermal necrolysis. Furthermore, those medications labeled by the US Food and Drug Administration (FDA) as carrying a risk of SJS/TEN were also compared with the common causes of SJS/TEN in Asian countries. Oxcarbazepine, sulfasalazine, COX-II inhibitors, and strontium ranelate were identified as new potential causes. In addition to sulfa drugs and beta-lactam antibiotics, quinolones were also a common cause. Only one acetaminophen-induced SJS was identified, while several medications (e.g., oseltamivir, terbinafine, isotretinoin, and sorafenib) labeled as carrying a risk of SJS/TEN by the FDA were not found to have caused any of the cases in the Asian countries investigated in this study.

Clinical and genetic differences between pustular psoriasis subtypes.

BACKGROUND: The term pustular psoriasis indicates a group of severe skin disorders characterized by eruptions of neutrophil-filled pustules. The disease, which often manifests with concurrent psoriasis vulgaris, can have an acute systemic (generalized pustular psoriasis [GPP]) or chronic localized (palmoplantar pustulosis [PPP] and acrodermatitis continua of Hallopeau [ACH]) presentation. Although mutations have been uncovered in IL36RN and AP1S3, the rarity of the disease has hindered the study of genotype-phenotype correlations. OBJECTIVE: We sought to characterize the clinical and genetic features of pustular psoriasis through the analysis of an extended patient cohort. METHODS: We ascertained a data set of unprecedented size, including 863 unrelated patients (251 with GPP, 560 with PPP, 28 with ACH, and 24 with multiple diagnoses). We undertook mutation screening in 473 cases. RESULTS: Psoriasis vulgaris concurrence was lowest in PPP (15.8% vs 54.4% in GPP and 46.2% in ACH, P < .0005 for both), whereas the mean age of onset was earliest in GPP (31.0 vs 43.7 years in PPP and 51.8 years in ACH, P < .0001 for both). The percentage of female patients was greater in PPP (77.0%) than in GPP (62.5%; P = 5.8 × 10-5). The same applied to the prevalence of smokers (79.8% vs 28.3%, P < 10-15). Although AP1S3 alleles had similar frequency (0.03-0.05) across disease subtypes, IL36RN mutations were less common in patients with PPP (0.03) than in those with GPP (0.19) and ACH (0.16; P = 1.9 × 10-14 and .002, respectively). Importantly, IL36RN disease alleles had a dose-dependent effect on age of onset in all forms of pustular psoriasis (P = .003). CONCLUSIONS: The analysis of an unparalleled resource revealed key clinical and genetic differences between patients with PPP and those with GPP.

Analysis of the leprosy agents Mycobacterium leprae and Mycobacterium lepromatosis in four countries.

OBJECTIVES: To differentiate the leprosy agents Mycobacterium leprae and Mycobacterium lepromatosis and correlate them with geographic distribution and clinicopathologic features. METHODS: Species-specific polymerase chain reactions were used to detect each bacillus in archived skin biopsy specimens from patients with leprosy from Brazil (n = 52), Malaysia (n = 31), Myanmar (n = 9), and Uganda (n = 4). Findings were correlated with clinical and pathologic data. RESULTS: Etiologic species was detected in 46 of the 52 Brazilian patients, including 36 patients with M leprae, seven with M lepromatosis, and three with both bacilli. The seven patients with sole M lepromatosis all had tuberculoid leprosy, whereas only nine of the 36 patients infected with M leprae exhibited this type, and the rest were lepromatous (P < .001). All patients with dual infections had lepromatous leprosy. Of the nine patients from Myanmar, six were test positive: four with M leprae and two with M lepromatosis. Of the Malaysian and Ugandan patients, only M leprae was detected in 27 of the 31 Malaysians and two of the four Ugandans. CONCLUSIONS: The leprosy agents vary in geographic distribution. Finding M lepromatosis in Brazil and Myanmar suggests wide existence of this newly discovered species. The leprosy manifestations likely vary with the etiologic agents.

Conidiobolomycosis in a young Malaysian woman showing chronic localized fibrosing leukocytoclastic vasculitis: a case report and meta-analysis focusing on clinicopathologic and therapeutic correlations with outcome.

BACKGROUND: Conidiobolomycosis (also known as rhinoentomophthoramycosis) is a rare cutaneous/mucosal fungal infection seen mainly in the tropical rain forest regions of the world that can be associated with disfiguring facial elephantiasis, and rarely, death. OBJECTIVE: To present an exemplary case report and perform a systematic review of the world's literature to more accurately describe the natural history and the effect of therapy on outcome in conidiobolomycosis. METHODS: Case report and meta-analysis of published case reports and series of conidiobolomycosis to determine which clinical, pathologic, mycologic, and treatment factors impact on prognosis. RESULTS: We document delay in diagnosis of conidiobolomycosis in a young Malaysian woman, whose biopsy showed pathognomonic features-massive tissue eosinophilia and Splendore-Hoeppli phenomenon surrounding broad hyphae. These findings coexisted with granuloma faciale-like changes (fibrosing leukocytoclastic vasculitis) and lymphedema. Treatment with multiple antifungals was followed by complete resolution. For the meta-analysis, pooled data from 199 cases (162 with full outcome data) from 120 reports revealed a similar course for most cases: a disease affecting healthy young adults who present with progressive nasal symptoms (eg, nasal obstruction) and central facial swelling and show improvement or cure after surgical excision and/or treatment with one or more antifungal agents in 83%. Persistent-progressive facial disease occurred in 11%, and 6% died rapidly of fungal infection. Presentation with facial elephantiasis correlated with persistent-progressive rhinoentomophthoramycosis and a longer duration of disease before diagnosis (P = 0.02). Lethal infections were significantly associated with nonstereotypical presentation (eg, orbital cellulitis), visceral infection, absence of the Splendore-Hoeppli phenomenon, presence of comorbidities (eg, immunosuppression, hematolymphoid malignancy), infection with Conidiobolus incongruus or Conidiobolus lamprauges (not Conidiobolus coronatus), lack of response to amphotericin B, and female sex (all P ≤ 0.002). The few sensitivity studies performed demonstrated in vitro multidrug resistance of Conidiobolus species to most available antifungal agents. LIMITATIONS: Publication bias, reporting heterogeneity, and data deficits may affect results. CONCLUSIONS: Conidiobolomycosis should be included in the differential diagnosis of patients who present with nasal symptoms and painless centrofacial swelling. Massive tissue eosinophilia and Splendore-Hoeppli material coating thin-walled hyphae confirms the clinical diagnosis. The granuloma faciale-like histology found in this case can explain the onset of facial lymphedema by fibroinflammatory destruction of lymphatic vessels; the duration of disease and severity of inflammation likely predicts whether the lymphedema is reversible or not. Although rhinoentomophthoramycosis ostensibly responds in vivo to most available antifungal agents, routine culture and susceptibility testing is recommended to better define the efficacy of these therapeutic agents.

Extramammary Paget's disease: a report of 2 cases and a review of the literature.

Extramammary Paget's disease (EMPD) is a rare disorder and may be found in the vulva, scrotum, penile area, perianal region and the groin. Frequently, it is associated with an underlying regional neoplasm or internal malignancy. We report 2 cases of EMPD; one involving the scrotal area and the other the vulva. Both were elderly patients who presented to the dermatologists with chronic eczematous lesions in the perineum that did not respond to topical treatment. Skin biopsies confirmed extramammary Paget's disease. Investigations for internal malignancies were negative. However, one of the patients defaulted treatment before surgery. The other patient had two excision surgeries with skin grafting to try to achieve tumour free margins. A long term follow-up was planned for him to look for recurrences. These cases emphasise that EMPD can mimic exudative dermatitis and present as a chronic non-healing lesion in the perineum for many years. Clinicians should have a high index of suspicion to pick up the disease early by biopsy. Various immunohistochemical markers not only can help differentiate other histological diagnoses but also help predict the presence of underlying malignancies. Management of EMPD included thorough search for occult or underlying malignancy followed by complete excision surgery with intraoperative frozen sections. Even then, recurrences are high for this disease and long term follow-up is advocated.