Traditionally when we think of type of lymphedema known as elephantiasis, we think of the mosquito spread parasitic infection called lymphatic filariasis that is so common in the tropical world. Here is an interesting collection of abstract about endemic non-filarial elephantiasis cause by exposure to certain alkalic clay soils in Ethiopia and Uganda.
Related Terms: Lymphedema, Pathogenesis, Podoconiosis, Nonfilarial elephantiasis, Lymphology, Attitude, Chronic care model, Stigma, Ethiopia, Tropical Disease
J Dtsch Dermatol Ges. 2010 Jan
Nenoff P, Simon JC, Muylowa GK, Davey G.
Laboratorium für medizinische Mikrobiologie, Mölbis, Germany. email@example.com
Podoconiosis or mossy foot is a form of non-filarial lymphedema. This geochemical elephantiasis is a disabling condition caused by the passage of microparticles of silica and aluminum silicates through the skin of people walking barefoot in areas with a high content of soil of volcanic origin. Podoconiosis is widespread in tropical Africa, Central America and North India, yet it remains a neglected and under-researched condition. The disabling effects of podoconiosis cause great hardship to patients. It adversely affects the economic (reduced productivity and absenteeism), social (marriage, education, etc.) and psychological (social stigma) well-being of those affected. Podoconiosis can be prevented; the main primary preventive measure is protective footwear. Secondary measures include a strict hygiene regimen and compression therapy, which can reverse initial lesions. Tertiary approaches include surgical management, such as shaving operations to reduce hyperplastic and verrucous elephantiasis.
Trans R Soc Trop Med Hyg. 2007 Dec Davey G, Tekola F, Newport MJ. Department of Community Health, Addis Ababa University, P.O. Box 9806, Addis Ababa, Ethiopia.
Keywords: Podoconiosis; Elephantiasis; Geochemical; Non-filarial elephantiasis
Corresponding author. Present address: P.O. Box 26905/1000, Addis Ababa, Ethiopia. Tel.: +251 911 388835; fax: +251 116 627876.
This article reviews peer-reviewed publications and book chapters on the history, epidemiology, genetics, ecology, pathogenesis, pathology and management of podoconiosis (endemic non-filarial elephantiasis). Podoconiosis is a non-infectious geochemical elephantiasis caused by exposure of bare feet to irritant alkalic clay soils. It is found in at least 10 countries in tropical Africa, Central America and northwest India, where such soils coexist with high altitude, high seasonal rainfall and low income. Podoconiosis develops in men and women working barefoot on irritant soils, with signs becoming apparent in most patients by the third decade of life.
Colloid-sized silicate particles appear to enter through the skin, are taken up into macrophages in the lower limb lymphatics and cause endolymphangitis and obliteration of the lymphatic lumen. Genetic studies provide evidence for high heritability of susceptibility to podoconiosis. The economic burden is significant in affected areas dependent on subsistence farming. Podoconiosis is unique in being an entirely preventable non-communicable disease. Primary prevention entails promoting use of footwear in areas of irritant soil; early stages are reversible given good foot hygiene, but late stages result in considerable economic and social difficulties, and require extended periods of elevation and occasionally nodulectomy.
Geshere Oli G, Tekola Ayele F, Petros B.
Department of Biology, College of Natural Sciences, Jimma University, Jimma, Ethiopia Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD, USA Microbial, Cellular and Molecular Biology Program Unit, Addis Ababa University, Addis Ababa, Ethiopia.
Objective To determine whether the elephantiasis in Midakegn district, central Ethiopia, is filarial or non-filarial (podoconiosis) using serological, parasitological and clinical examinations, and to estimate its prevalence. Methods At house-to-house visits in 330 randomly selected households, all household members who had elephantiasis were interviewed and clinically examined at the nearby health centre to confirm the presence of elephantiasis, check the presence of scrotal swelling and rule out the other causes of lymphoedema. A midnight blood sample was obtained from each participant with elephantiasis for microscopic examination of Wuchereria bancrofti microfilaria. A daytime blood sample was obtained from half of the participants for serological confirmation using the immuno-chromatographic test card. Results Consistent with the features of podoconiosis, none of the elephantiasis cases had consistently worn shoes since childhood; 94.3% had bilateral swelling limited below the level of the knees; no individual had thigh or scrotal elephantiasis; parasitological test for microfilariae and serological tests for W. bancrofti antigen were negative in all samples. The prevalence of the disease was 7.4% and it peaked in the third decade of life, the most economically active age. Conclusion Midakegn District has a high prevalence of podoconiosis and no filarial elephantiasis. Prevention, treatment and control of podoconiosis must be among the top priorities of public health programmes.
Ayele FT, Adeyemo A, Finan C, Hailu E, Sinnott P, Burlinson ND, Aseffa A, Rotimi CN, Newport MJ, Davey G.
Source Center for Research on Genomics and Global Health, National Human Genome Research Institute, National Institutes of Health, Bethesda, MD 20892-5635, USA. firstname.lastname@example.org
BACKGROUND: Podoconiosis is a tropical lymphedema resulting from long-term barefoot exposure to red-clay soil derived from volcanic rock. The World Health Organization recently designated it as a neglected tropical disease. Podoconiosis develops in only a subgroup of exposed people, and studies have shown familial clustering with high heritability (63%).
METHODS: We conducted a genomewide association study of 194 case patients and 203 controls from southern Ethiopia. Findings were validated by means of family-based association testing in 202 family trios and HLA typing in 94 case patients and 94 controls.
RESULTS: We found a genomewide significant association of podoconiosis with the single-nucleotide polymorphism (SNP) rs17612858, located 5.8 kb from the HLA-DQA1 locus (in the allelic model: odds ratio, 2.44; 95% confidence interval [CI], 1.82 to 3.26; P=1.42×10(-9); and in the additive model: odds ratio, 2.19; 95% CI, 1.66 to 2.90; P=3.44×10(-8)), and suggestive associations (P<1.0×10(-5)) with seven other SNPs in or near HLA-DQB1, HLA-DQA1, and HLA-DRB1. We confirmed these associations using family-based association testing. HLA typing showed the alleles HLA-DRB1*0701 (odds ratio, 2.00), DQA1*0201 (odds ratio, 1.91), and DQB1*0202 (odds ratio, 1.79) and the HLA-DRB1*0701-DQB1*0202 haplotype (odds ratio, 1.92) were risk variants for podoconiosis.
CONCLUSIONS: Association between variants in HLA class II loci with podoconiosis (a noncommunicable disease) suggests that the condition may be a T-cell-mediated inflammatory disease and is a model for gene-environment interactions that may be relevant to other complex genetic disorders. (Funded by the Wellcome Trust and others.).
J Dtsch Dermatol Ges. 2009 May
Nenoff P, Simon JC, Muylowa GK, Davey G. Laboratory for Medical Microbiology, Mölbis, Germany.
Correspondence to Prof. Dr. med. Pietro Nenoff Laboratorium für medizinische Mikrobiologie Partnerschaft Dr. rer. nat. Jürgen Herrmann, Prof. Dr. med. Pietro Nenoff & Dr. med. Constanze Krüger Straße des Friedens 8 D-04579 Mölbis Tel.: +49-34347-50-323 / Fax: +49-34347-50-123 E-mail: email@example.com
geochemical tropical disease • Ethiopia • Uganda • secondary lymphoedema • non-filarial elephantiasis • aluminium silicate • volcanic soil
Summary Podoconiosis or mossy foot is a form of non-filarial lymphedema. This geo-chemical elephantiasis is a disabling condition caused by the passage of microparticles of silica and aluminum silicates through the skin of people walking barefoot in areas with a high content of soil of volcanic origin. Podoconiosis is widespread in tropical Africa, Central America and North India, yet it remains a neglected and under-researched condition. The disabling effects of podoco-niosis cause great hardship to patients. It adversely affects the economic (reduced productivity and absenteeism), social (marriage, education, etc.) and psychological (social stigma) well-being of those affected. Podoconiosis can be prevented; the main primary preventive measure is protective footwear. Secondary measures include a strict hygiene regimen and compression therapy, which can reverse initial lesions. Tertiary approaches include surgical management, such as shaving operations to reduce hyperplastic and verru-cous elephantiasis.
Kelemu Destaa, Meskele Ashinea and Gail Daveyb, aMossy Foot Prevention and Treatment Association, P.O. Box 311, Sodo, Wolaitta, Ethiopia bDepartment of Community Health, Addis Ababa University, P.O. Box 26905/1000, Addis Ababa, Ethiopia
Received 19 October 2006; revised 4 December 2006; accepted 5 December 2006. Available online 21 February 2007.
Podoconiosis is a geochemical condition resulting in lower limb elephantiasis similar to that seen in chronic filarial disease. In podoconiosis-endemic areas, diagnosis of the condition must often take place in the community setting, where laboratory facilities are unavailable. In this study, 205 patients in Wolaitta zone, southern Ethiopia, were examined according to standard clinical practice. A capillary blood sample was taken at midnight for thick film examination. In a subsample of 117 patients, rapid antigen testing using Binax™ antigen cards was also performed. Both tests were negative in all patients. In podoconiosis-endemic areas, clinical examination is a valid means of diagnosing podoconiosis.
Keywords: Podoconiosis; Non-filarial elephantiasis; Geochemical disease; Diagnosis; Ethiopia
Mar 18, 2012
Gail Davey a, Moses Bockarie b, Samuel Wanji c, David Addiss d, Claire Fuller e, LeAnne Fox f, Mike Mycoskie g, Mark Gruin h, Aster Tsegaye i, Fasil Tekola Ayele j, Melanie Newport a
In the past 5 years, important progress in podoconiosis research and control has been made. The global distribution of this ascending, geochemical lymphoedema has been updated, advances have been made in disease assessment and treatment, and advocacy has successfully brought podoconiosis to the global stage. We highlight some of this progress here, and announce the launch of a new international initiative.
Wanji and colleagues1 and Ruberanziza and colleagues2 have shown elephantiasis in the absence of filarial parasites during mapping in Cameroon and Rwanda, respectively. A new staging system for podoconiosis has been developed and validated, and used to assess the simple treatment regimen developed by a patient-led and community-based control programme in southern Ethiopia.3 Ethical approaches to research in the remote communities in which podoconiosis patients are usually found have been developed,4 and issues related to community attitudes, quality of life, and stigma have been documented.5 Ongoing research in Ethiopia and Cameroon aims to identify the locus of a susceptibility gene and to characterise the minerals that trigger podoconiosis. Other studies are investigating immunological changes associated with podoconiosis, documenting overlaps with other common tropical diseases, and exploring behavioural issues that will be vital to understand as prevention programmes increase shoe distribution to high-risk children.
Much progress has also been made in terms of disease advocacy: in February, 2011, WHO included podoconiosis in its list of neglected tropical diseases (NTDs). A page focusing on the disease is available on the WHO website. On Nov 12, 2011, the first General Assembly of the Ethiopian National Podoconiosis Action Network (NaPAN) was held. The meeting brought together researchers, policy makers, clinicians, and representatives of all the groups now offering care to patients with podoconiosis in Ethiopia. NaPAN seeks to help these groups share expertise and translate research into practice, with the aim that, eventually, all patients can access treatment, and residents of all endemic areas can prevent new disease through use of shoes.
Most recently, we met to plan the public launch of “Footwork”, the International Podoconiosis Initiative. Footwork aims to bring together public and private partners to prevent and treat podoconiosis, integrating control with that of other NTDs in areas of co-endemicity, and partnering with organisations that work in foot-related disorders to advocate for shoes as “the new bednets”. We look forward to welcoming new partners to this group, and, further in the future, to a world free of podoconiosis.
Gail Daveya, Ewenat GebreHannaa, Adebowale Adeyemob, Charles Rotimib, Melanie Newportc and Kelemu Destad aDepartment of Community Health, Addis Ababa University, P.O. Box 26905/1000, Addis Ababa, Ethiopia
bNational Human Genome Center, Howard University, 2041 Georgia Avenue NW, Cancer Center Building, Room 61, Washington DC 20060, USA cBrighton and not allowed Medical School, University of not allowed, Falmer, Brighton BN1 9PS, UK dMossy Foot Prevention and Treatment Association, P.O. Box 251, Sodo, Wolaitta, Ethiopia
Received 30 November 2005; revised 19 May 2006; accepted 19 May 2006. Available online 1 August 2006.
Podoconiosis (endemic non-filarial elephantiasis) is a geochemical disease occurring in individuals exposed to red clay soil derived from alkalic volcanic rock. It is a chronic, debilitating disorder and a considerable public health problem in at least 10 countries in tropical Africa, Central America and northern India. Only a small proportion of individuals exposed to red clay develop disease and familial clustering of cases occurs, so we tested the hypothesis that disease occurs in genetically susceptible individuals on exposure to an environmental element in soil. Using multiple statistical genetic techniques we estimated sibling recurrence risk ratio (λs) and heritability for podoconiosis, and conducted segregation analysis on 59 multigenerational affected families from Wolaitta Zone, southern Ethiopia. We estimated the λs to be 5.07. The heritability of podoconiosis was estimated to be 0.629 (SE 0.069, P = 1 × 10-7). Segregation analysis showed that the most parsimonious model was that of an autosomal co-dominant major gene. Age and use of footwear were significant covariates in the final model. Host genetic factors are important determinants of susceptibility to podoconiosis. Identification of the gene(s) involved will lead to better understanding of the gene-environment interactions involved in the pathogenesis of podoconiosis and other complex multifactorial conditions.
Keywords: Elephantiasis; Podoconiosis; Genetic susceptibility; Gene- environment interaction; Geochemical; Heritability
Current Opinion in Infectious Diseases. 18(2):119-122, April 2005.
Fuller, L Claire Abstract: Purpose of review: Podoconiosis is a noncommunicable disease producing lymphoedema of the lower limbs; it affects predominantly barefoot agricultural workers in the tropics. Why should this be of interest to a journal of infectious disease? For many years this disease has not been widely recognized as distinct from lymphatic filariasis and yet it may affect about 10% of populations in volcanic tropical highlands. It produces considerable morbidity associated with limb lymphoedema, impacting on economically productive age groups. As it does not fall into the briefs of infectious or chronic disease initiatives of the World Health Organization, it has been difficult to attract funds for research and for the development of community management approaches. The aim of this review is to describe details of the clinical features, management, epidemiological significance and evidence for the underlying aetiology of this poorly understood condition. Recent findings: A recent comprehensive study in Ethiopia by Destas et al. identified a mean zonal prevalence of 5.46% of the population with 64% being in the economically productive age group. Otherwise there are no other contemporary epidemiological publications in this field. Summary: Podoconiosis is thought to be a geochemical disease induced by the absorption of ultrafine silica particles from the soil (konia) through the skin of the feet (podos) in susceptible individuals, leading to a progressive obliterative endolymphangitis.
Trop Doct. 2003 Oct Destas K, Ashine M, Davey G. Mossy Foot Association, PO Box 251, Wolaitta Soddo, Ethiopia.
The survey was undertaken to establish the point prevalence of overt podoconiosis (endemic non-filarial elephantiasis) in Wolaitta zone, Southern Ethiopia, and also to determine whether age- or sex-related prevalence differences exist. A cross-sectional survey was performed during May-September 2001 among 33 678 residents of 4210 households randomly selected from all seven woredas (administrative districts) of Wolaitta zone. Trained data collectors administered a simple questionnaire and examined household residents for signs of podoconiosis. Of the residents 1890 had overt signs of podoconiosis. The mean zonal prevalence weighted for the woreda size was 5.46%. Most of cases (64%) occurred in the economically productive age groups (16-45 years). The male:female ratio was 1:0.98, reflecting the gender ratio of the zone. Podoconiosis is an important chronic public health problem affecting both men and women in areas of irritant soil. Further research is necessary to establish the economic effects of the condition.
PMID: 14620426 PubMed - indexed for MEDLINE
Acta Trop. 2001 Feb 23
Onapa AW, Simonsen PE, Pedersen EM. Vector Control Division, Ministry of Health, PO Box 1661, Kampala, Uganda.
Following reports of a high frequency of elephantiasis in Kwen County (Kapchorwa District) on the slopes of Mt. Elgon in Uganda, a baseline survey for lymphatic filariasis was carried out in three villages in the affected area. Individuals aged 1 year and above were examined for chronic manifestations of lymphatic filariasis, and for specific circulating filarial antigens and microfilariae of Wuchereria bancrofti. Elephantiasis was observed in all age groups from 10 years and above. The overall prevalence was 4.5%, and the prevalence among individuals aged >/=20 years was 8.2%. Males and females were equally affected. However, there were only few cases of hydrocele (overall prevalence in males of 1.0%) and blood examinations were negative for W. bancrofti circulating antigens and microfilariae. Sampling of potential filariasis mosquito vectors revealed low densities of Anopheles gambiae s.l. and An. funestus, and none of these were infected with filarial larvae. In view of the low hydrocele to elephantiasis ratio, the absence of filarial infection in humans and mosquitoes, the high altitude (1500-2200 m above sea level) and the volcanic soil type, it is concluded that elephantiasis seen in this area is not of filarial origin but most likely is due to podoconiosis (endemic non-filarial elephantiasis).
Keywords: Elephantiasis; Podoconiosis; Filariasis; Volcanic soils; Uganda
Alemu G, Tekola Ayele F, Daniel T, Ahrens C, Davey G.
SOS Children's Villages International, Addis Ababa, Ethiopia.
BACKGROUND: Podoconiosis is an environmental lymphoedema affecting people living and working barefoot on irritant red clay soil. Podoconiosis is relatively well described in southern Ethiopia, but remains neglected in other parts of the Ethiopian highlands. This study aimed to assess the burden of podoconiosis in rural communities in western Ethiopia.
METHODOLOGY/PRINCIPAL FINDINGS: A cross-sectional study was conducted in Gulliso woreda (district), west Ethiopia. A household survey in the 26 rural kebeles (villages) of this district was conducted to identify podoconiosis patients and to measure disease prevalence. A more detailed study was done in six randomly selected kebeles to describe clinical features of the disease, patients' experiences of foot hygiene, and shoe wearing practice. 1,935 cases of podoconiosis were registered, giving a prevalence of 2.8%. The prevalence was higher in those aged 15-64 years (5.2%) and in females than males (prevalence ratio 2.6∶1). 90.3% of patients were in the 15-64 year age group. In the detailed study, 335 cases were interviewed and their feet assessed. The majority of patients were farmers, uneducated, and poor. Two-third of patients developed the disease before the age of thirty. Almost all patients (97.0%) had experienced adenolymphangitis (ALA - red, hot legs, swollen and painful groin) at least once during the previous year. Patients experienced an average of 5.5 ALA episodes annually, each of average 4.4 days, thus 24 working days were lost annually. The incidence of ALA in podoconiosis patients was higher than that reported for filariasis in other countries. Shoe wearing was limited mainly due to financial problems.
CONCLUSIONS: We have documented high podoconiosis prevalence, frequent adenolymphangitis and high disease-related morbidity in west Ethiopia. Interventions must be developed to prevent, treat and control podoconiosis, one of the core neglected tropical diseases in Ethiopia.
The Lancet, Volume 379, Issue 9820, Page 996, 17 March 2012
“Diseases need advocates”, says David Molyneux, from the University of Liverpool's School of Tropical Medicine, UK, “and Gail has been the advocate for ‘podo…what’ with huge success”. Now, let's pause for a moment to get our facts straight. “Podo…what?” is the most common shorthand for podoconiosis; otherwise known, when it is known at all, as endemic non-fılarial elephantiasis. And the Gail in question is Gail Davey, who is summed up pithily by one of her old PhD students, Fasil Tekola, as “a voice for the voiceless podoconiosis patients and affected poor families—fighting the good fight”. And it's a fight that Davey looks like she's starting to win. For decades podoconiosis has languished as a footnote in textbooks on tropical diseases, but this month will see the arrival of the International Podoconiosis Initiative, which will “bring together private and public partners to prevent and treat podoconiosis”, says Davey. “We're hoping to integrate podo control with that of other neglected tropical diseases wherever possible, and to partner with organisations working on foot-related conditions to advocate for shoes as ‘the new bednets’.” That's because podoconiosis is entirely preventable, and only occurs wherever irritant red clay soils coexist with high altitude, high rainfall, and a level of income that puts footwear out of the reach of many. By forging partnerships with footwear companies, Davey has been able to champion the provision of shoes as a public health intervention with benefits that extend far beyond podoconiosis.
The launch of the International Podoconiosis Initiative will mark the next step in what has been an incredible journey for Davey; one that has taken her to bustling Addis Ababa in Ethiopia and, eventually, back to the UK, where she has been Reader in Global Health at Brighton and Sussex Medical School since 2010. Schooled in Oxford, the young Davey was “either standing on her head or had it buried in a book”, according to a report card that her mother delights in recounting. It's hard not to suspect she was one of those perfect pupils, academic and athletic by turns. But Davey sounds so bashful when talking about herself that pressing her further feels like an act of cruelty. Sigurd Hanson, of the International Orthodox Christian Charities, and who had a crucial role in helping Davey “move in development circles” during her time in Ethiopia, sums up her attitude to self-promotion succinctly: “she has no ego”. “Partly by how she taught, and by really opening our eyes far beyond the curriculum”, a biology teacher ignited Davey's passion for medicine and the biological sciences—a passion almost extinguished by 3 “dire” years doing preclinical medicine at Cambridge University in the mid-1980s. But as grim as all the exam cramming was, it was at Cambridge that Davey first became interested in medicine outside the UK. After dabbling in a few overseas projects, a 6-month stint in Zimbabwe crystallised Davey's desire to pursue medicine and research outside the UK. Brushing up on her epidemiology skills at the London School of Hygiene and Tropical Medicine (LSHTM) was the logical next step, and it was early during her time there as a research fellow that she met her husband Richard, a professional marathon runner. When Richard picked up a career-ending injury in 2000, their conversations turned increasingly to working abroad, Davey explains, and that's where an old contact from the LSHTM and founder of THET (Tropical Health and Education Trust), Eldryd Parry, came in.
“When Gail was working in London she talked to me about the possibility of work in east Africa, in a country where Richard could also contribute through his marathon excellence”, recalls Parry, “and I knew that someone of her singleminded commitment would make a go of Ethiopia and would make a considerable contribution”. Through his contacts with the Dean of the Addis Ababa University Medical Faculty, Parry found out there was a position open at what is now the School of Public Health. “The significant point is that she was prepared to take a local appointment on local terms, and without the comfortable cushion of a major agency or a research grant. That was a risk and was brave”, Parry says.
One of the things that helped Davey accept that risk is her Christian faith, and it also helped her adapt to a country in which, she says, “faith is very much a part of every day life”. “Whether it's Orthodox or Muslim or Protestant, there's very little secular life in Ethiopia, so that was a good fit”, she explains. Davey also picked up Amharic quickly and was able to “look around a bit and see what wasn't being covered”. From her first contact with the disease, assessing a funding application by the Mossy Foot Treatment and Prevention Association at the behest of the British Ambassador, Davey knew that in podoconiosis she had found a cause worth advocating. And since then, says Molyneux, she has “taken the seminal work of [E W] Price in the 1970s and 1980s to a new dimension”, both in terms of the science and getting the condition recognised as a neglected tropical disease. All by “including and involving Ethiopians at every stage because it's going to be Ethiopians who solve the problem”, and without “zooming around in big white cars”, laughs Davey. “I think it's small things like that that sort of signal that you're coming along as an equal and that you're very happy to assist and facilitate, but you're not coming along pretending to know lots of answers”, she says. Unless, of course, the question happens to be “podo…what?”