Stephen L. Walker
University of London
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Anais Brasileiros De Dermatologia | 2008
Indira P. Kahawita; Stephen L. Walker; Diana N. J. Lockwood
Leprosy reactions are a major cause of nerve damage and morbidity in a significant proportion of leprosy patients. Reactions are immunologically mediated and can occur even after successful completion of multi-drug therapy. This review focuses on the epidemiology, pathology and treatment of leprosy type 1 reactions, erythema nodosum leprosum and silent neuropathy.
British Journal of Dermatology | 2007
Stephen L. Walker; Mahesh Shah; V. G. Hubbard; H.M. Pradhan; M. Ghimire
Background Skin problems are the commonest reason for people accessing healthcare services in Nepal but there is little information about the prevalence of skin disease.
PLOS Neglected Tropical Diseases | 2017
Oriol Mitjà; Michael Marks; Laia Bertran; Karsor Kollie; Daniel Argaw; Ahmed H. Fahal; Christopher Fitzpatrick; L. Claire Fuller; Bernardo Garcia Izquierdo; Roderick J. Hay; Norihisa Ishii; Christian Johnson; Jeffrey V. Lazarus; Anthony O. Meka; Michele E. Murdoch; Sally-Ann Ohene; Pam Small; Andrew C. Steer; Earnest Njih Tabah; Alexandre Tiendrebeogo; Lance A. Waller; Rie Roselyne Yotsu; Stephen L. Walker; Kingsley Asiedu
Neglected tropical diseases (NTDs) are communicable diseases that occur under conditions of poverty and are concentrated almost exclusively in impoverished populations in the developing world. NTDs affect more than 1000 million people in tropical and subtropical countries, costing developing economies billions of dollars every year. Effective control of NTDs can be achieved with the use of large-scale delivery of single-dose preventive chemotherapy (PC) or intensified disease management (IDM) or both, as is the case for some diseases such as lymphatic filariasis, trachoma, and yaws. Several NTDs exhibit significant cutaneous manifestations that are associated with long-term disfigurement and disability, including Buruli ulcer (BU); cutaneous leishmaniasis (CL); leprosy; mycetoma; yaws; hydrocele and lymphoedema (resulting from lymphatic filariasis); and depigmentation, subcutaneous nodules, severe itching, and hanging groin (resulting from onchocerciasis). Skin examination offers an opportunity to screen people in the communities or children in schools to identify multiple conditions in a single visit. This common approach to skin diseases justifies the integrated delivery of health care interventions to both increase cost-effectiveness and expand coverage. WHO’s Department of Control of NTDs (WHO/NTD) plans to promote an integrated strategy for the skin NTDs requiring IDM. Targeting skin NTDs also provides a platform for treatment of common skin conditions and, therefore, has wider public health benefits. An informal panel of experts (writing this manuscript) was established to help develop guidance in support of the new WHO strategic direction and to develop a proposal for a change in policy for the integrated control and management of the skin NTDs. A symposium at the 2015 ASTMH meeting[1] initiated a discussion of opportunities around integration of surveillance and control of NTDs that affect the skin, but this paper moves these ideas forward and includes some initial recommendations about how these opportunities could be realised. We aim to provide specific pragmatic information and actual recommendations about potential surveillance and management approaches.
PLOS Neglected Tropical Diseases | 2014
Stephen L. Walker; Eglantine Lebas; Shimelis N. Doni; Diana N. J. Lockwood; Saba M. Lambert
Background Erythema nodosum leprosum (ENL) is a debilitating multisystem disorder which complicates leprosy. It is characterised by fever, malaise and painful erythematous cutaneous nodules. ENL is often recurrent or chronic in nature and frequently severe. Patients often require prolonged treatment with high doses of oral corticosteroids. There are no data on the mortality associated with treated ENL. Methodology The notes of patients who were admitted, discharged, transferred to another facility or died with a diagnosis of leprosy or a leprosy-related complication for a five year period were reviewed. Result/Discussion 414 individuals were identified from the ward database. 312 (75.4%) patient records were located and reviewed. Ninety-nine individuals had ENL and 145 had a Type 1 reaction. The median age of individuals with ENLwas 25 years. Eight patients with erythema nodosum leprosum died compared with two diagnosed with Type 1 reaction. This difference is statistically significant (p = 0.0168, Fishers Exact Test). There is a significant mortality and morbidity associated with ENL in this Ethiopian cohort. The adverse outcomes seen are largely attributable to the chronic administration of oral corticosteroids used to control the inflammatory and debilitating symptoms of the condition.
PLOS Neglected Tropical Diseases | 2011
Stephen L. Walker; P.G. Nicholls; Sushmita Dhakal; Ra Hawksworth; Murdo Macdonald; Kishori Mahat; Shudan Ruchal; Sushma Hamal; Deanna A. Hagge; Kapil D. Neupane; Diana N. J. Lockwood
Background Leprosy Type 1 reactions are a major cause of nerve damage and the preventable disability that results. Type 1 reactions are treated with oral corticosteroids and there are few data to support the optimal dose and duration of treatment. Type 1 reactions have a Th1 immune profile: cells in cutaneous and neural lesions expressing interferon-γ and interleukin-12. Methylprednisolone has been used in other Th1 mediated diseases such as rheumatoid arthritis in an attempt to switch off the immune response and so we investigated the efficacy of three days of high dose (1 g) intravenous methylprednisolone at the start of prednisolone therapy in leprosy Type 1 reactions and nerve function impairment. Results Forty-two individuals were randomised to receive methylprednisolone followed by oral prednisolone (n = 20) or oral prednisolone alone (n = 22). There were no significant differences in the rate of adverse events or clinical improvement at the completion of the study. However individuals treated with methylprednisolone were less likely than those treated with prednisolone alone to experience deterioration in sensory function between day 29 and day 113 of the study. The study also demonstrated that 50% of individuals with Type 1 reactions and/or nerve function impairment required additional prednisolone despite treatment with 16 weeks of corticosteroids. Conclusions The study lends further support to the use of more prolonged courses of corticosteroid to treat Type 1 reactions and the investigation of risk factors for the recurrence of Type 1 reaction and nerve function impairment during and after a corticosteroid treatment. Trial Registration Controlled-Trials.comISRCTN31894035
PLOS Neglected Tropical Diseases | 2008
Stephen L. Walker; P.G. Nicholls; C. Ruth Butlin; José Augusto da Costa Nery; Hemanto K. Roy; Emanuel Rangel; Anna Maria Sales; Diana N. J. Lockwood
Objectives To develop a valid and reliable quantitative measure of leprosy Type 1 reactions. Methods A scale was developed from previous scales which had not been validated. The face and content validity were assessed following consultation with recognised experts in the field. The construct validity was determined by applying the scale to patients in Bangladesh and Brazil who had been diagnosed with leprosy Type 1 reaction. An expert categorized each patients reaction as mild or moderate or severe. Another worker applied the scale. This was done independently. In a subsequent stage of the study the agreement between two observers was assessed. Results The scale had good internal consistency demonstrated by a Cronbachs alpha >0.8. Removal of three items from the original scale resulted in better discrimination between disease severity categories. Cut off points for Type 1 reaction severities were determined using Receiver Operating Characteristic curves. A mild Type 1 reaction is characterized using the final scale by a score of 4 or less. A moderate reaction is a score of between 4.5 and 8.5. A severe reaction is a score of 9 or more. Conclusions We have developed a valid and reliable tool for quantifying leprosy Type 1 reaction severity and believe this will be a useful tool in research of this condition, in observational and intervention studies, and in the comparison of clinical and laboratory parameters.
PLOS Neglected Tropical Diseases | 2015
Stephen L. Walker; Marivic Balagon; Joydeepa Darlong; Shimelis N. Doni; Deanna A. Hagge; Vikas Halwai; Annamma John; Saba M. Lambert; Armi Maghanoy; José Augusto da Costa Nery; Kapil D. Neupane; P.G. Nicholls; Vivek V. Pai; Pawan Parajuli; Anna Maria Sales; Euzenir Nunes Sarno; Mahesh Shah; Digafe Tsegaye; Diana N. J. Lockwood
Erythema nodosum leprosum (ENL) is a severe multisystem immune mediated complication of borderline lepromatous leprosy and lepromatous leprosy. ENL is associated with skin lesions, neuritis, arthritis, dactylitis, eye inflammation, osteitis, orchitis, lymphadenitis and nephritis. The treatment of ENL requires immunosuppression, which is often required for prolonged periods of time and may lead to serious adverse effects. ENL and its treatment is associated with increased mortality and economic hardship. Improved, evidence-based treatments for ENL are needed; however, defining the severity of ENL and outcome measures for treatment studies is difficult because of the multiple organ systems involved. A cross-sectional study was performed, by the members of the Erythema Nodosum Leprosum International STudy (ENLIST) Group, of patients with ENL attending seven leprosy referral centres in Brazil, Ethiopia, India, Nepal, the Philippines and the United Kingdom. We systematically documented the clinical features and type of ENL, its severity and the drugs used to treat it. Patients with chronic ENL were more likely to be assessed as having severe ENL. Pain, the most frequent symptom, assessed using a semi-quantitative scale was significantly worse in individuals with “severe” ENL. Our findings will determine the items to be included in a severity scale of ENL which we are developing and validating. The study also provides data on the clinical features of ENL, which can be incorporated into a definition of ENL and used for outcome measures in treatment studies.
PLOS Neglected Tropical Diseases | 2012
Anna L. Cogen; Stephen L. Walker; Chrissy h. Roberts; Deanna A. Hagge; Kapil D. Neupane; Saraswoti Khadge; Diana N. J. Lockwood
Background Leprosy, a chronic granulomatous disease affecting the skin and nerves, is caused by Mycobacterium leprae (M. leprae). The type of leprosy developed depends upon the host immune response. Type 1 reactions (T1Rs), that complicate borderline and lepromatous leprosy, are due to an increase in cell-mediated immunity and manifest as nerve damage and skin inflammation. Owing to the increase in inflammation in the skin of patients with T1Rs, we sought to investigate the activation of the innate immune system during reactionary events. Specifically, we investigated the expression levels of human beta-defensins (hBDs) 2 and 3 in the skin of patients with T1Rs, in keratinocytes, and in macrophages stimulated with M. leprae and corticosteroids. Results Skin biopsies from twenty-three patients with Type 1 reactions were found to have higher transcript levels of hBD3 as compared to fifteen leprosy patients without Type 1 reactions, as measured by qPCR. Moreover, we observed that keratinocytes but not macrophages up-regulated hBD2 and hBD3 in response to M. leprae stimulation in vitro. Corticosteroid treatment of patients with T1Rs caused a suppression of hBD2 and hBD3 in skin biopsies, as measured by qPCR. In vitro, corticosteroids suppressed M. leprae-dependent induction of hBD2 and hBD3 in keratinocytes. Conclusions This study demonstrates that hBD3 is induced in leprosy Type 1 Reactions and suppressed by corticosteroids. Furthermore, our findings demonstrate that keratinocytes are responsive to M. leprae and lend support for additional studies on keratinocyte innate immunity in leprosy and T1Rs. Trial Registration Controlled-Trials.com ISRCTN31894035
Clinical and Experimental Dermatology | 2009
V. G. Hubbard; D. J. Goddard; Stephen L. Walker
The use of digital cameras by clinicians is increasing, and raises issues concerning patient consent and confidentiality. An online survey of members of the British Association of Dermatologists was conducted using an anonymous questionnaire. In total, 339 individuals completed the survey, a response rate of 37.6%. The survey shows that there are variations in the type of consent obtained by clinicians taking digital images of patients, and the methods used to store images are not always compliant with current UK legislation. Guidelines would help to improve and standardize the practice of clinicians who take digital images of patients.
Tropical Doctor | 2007
B Pandey; K Shrestha; J Lewis; Ra Hawksworth; Stephen L. Walker
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.