Podoconiosis

Classification according to ICD-10
I89.0	Lymphedema, not elsewhere classified
ICD-10 online (WHO version 2019)

The Podoconiosis (πούς Greek, genitive ποδός "foot" and κονία, konia "dust") is a non-infectious type of elephantiasis . It is also called endemic, non- filarial elephantiasis, "mossy foot" disease, elephant foot disease, or Price's disease ("Price's disease").

distribution

Podoconiosis is common in the highlands of tropical Africa , Central America and northern India . The following have a high prevalence : Uganda , Tanzania , Kenya , Rwanda , Burundi , Cameroon , Sudan and Ethiopia . In Ethiopia Podoconiosis is one-fifth of the country's endemic and in endemic areas far more common than AIDS . Various studies show prevalences up to 9.1%. There are probably one million podoconiosis sufferers in Ethiopia, 64% of them of working age.

Differentiation from filarial elephantiasis

Podoconiosis is one of the tropical lymphedemas and begins in the feet, from where it spreads over the legs to the knees, and only rarely further to the groin, while the filarial elephantiasis or mosquito- caused parasites ( filaria ) lymphatic filariasis (LF) is usually first visible on the groin. Another distinguishing criterion is that podoconiosis, in contrast to filariasis, usually occurs on both sides and also preferably in highland locations, while LF is more common at altitudes below 1000 meters above sea level.

root cause

Podoconiosis is caused by microparticles found in soils with a high content of red laterites of volcanic origin. In people who walk barefoot, these particles penetrate through the intact skin into the subcutaneous tissue, where they lead to an inflammatory process. Edema and subsequent fibrosis of the lymphatics and lymph nodes reduce or close the lumen of the lymphatics, which leads to a blockage of the lymph drainage . Over the years, this eventually develops into bilateral asymmetrical lymphedema of the lower extremities, mostly below the knee.

Geological and climatic factors

• Regions with red, silicate-rich earth of volcanic origin ( quartz , aluminum , magnesium , iron , alkali metals such as sodium and potassium )
• Highland regions with an altitude of over 1000 meters above sea level
• Sufficient seasonal rainfall (more than 1000 mm annually)

Genetic factor

The inflammatory reaction leading to podoconiosis only occurs when there is a corresponding genetic predisposition, so that not all people walking barefoot but only a minority of them eventually become ill.

Poverty factor

Mostly the poor rural population is affected, mainly farmers, but also mine workers who have to go to work barefoot for reasons of poverty. The disease also occurs frequently in weavers who sit barefoot on the floor. Shoes are a priceless luxury for most of the rural population. Robust and resistant as well as completely closed shoes z. B. a market niche in the rural regions of Ethiopia.

pathology

Podoconiosis

Podoconiosis is manifested by massive swelling of the feet and legs. The disease usually occurs in the first and second decades of a person's life, regardless of gender . Thereafter the prevalence increases steadily and reaches its peak in the sixth decade of life.

Prodromal symptoms

The clinical picture begins with the stage of pre-elephantiasis with some prodromal symptoms :

• burning feet and legs, mostly at night
• slight swelling of the middle toes
• itchy feet
• throbbing big toes
• Fungal and bacterial infections of the affected skin
• rough, thick skin, sometimes with wart-like growths
• greyish discolored skin
• strong, unpleasant odor
• Spread of the forefoot
• Edema on the sole of the foot with escaping tissue fluid
• Hyperkeratosis with moss-like formation of the papillomas
• stiff toes

Progressive symptoms

The high tissue pressure of the lymphedema results in a thickening of the dermis and epidermis with excessive keratin production in the sense of papillomatosis cutis, which gives the affected skin a moss-like consistency typical of podoconiosis. The sensitivity of the peripheral nerves on the toes and forefoot is retained. In the course of the disease, the spaces between the toes can even grow together, leading to ankylosis of the interphalangeal joints . Podoconiosis is often associated with acute adenolymphangitis (ALA): a painful inflammation of the feet and legs with swollen lymph nodes and fever. (These seem to be related to the type of water bag.) A common, very unpleasant symptom is the odor emanating from the inflammatory tissue.

There are two types of progressive symptoms:

• Water bag type: The swellings are soft and give way to pressure.
• Leathery type: The swellings are hard and fibrotic with hardening knots of tissue.

consequences

Economic consequences

Podoconiosis has a major negative impact on social and economic aspects of the life of those affected. Often times, they are unable to walk or do everyday family chores and chores. Since employers, for example, are afraid of being infected, many of those affected also lose their jobs and become poor. Studies show an average loss of labor of 45 percent per year due to the disease. In 2005 it was estimated that the disease in the Wolaita Zone in southern Ethiopia (1.5 million inhabitants) costs 16 million dollars a year. This results in economic losses of $ 200 million per year across Ethiopia. Those affected stated that they worked less (21.9%) and less often (44.9%) or that they had stopped working completely (8%). 96.4% noticed a decrease / deterioration in their income.

Stigma

Those affected live as outcasts. The reasons are the smell of the inflamed skin, but also a lack of information about the cause of the disease. By observing familial clusters of podoconiosis, the assumption is widespread that the disease is inherited. Stigmatized by podoconiosis, those affected are discriminated against, especially for fear of infection. Some attribute the disease to "witchcraft" or a curse, others believe that you can get infected by using the same washing vessels. Such ignorance often leads to the sick being treated like lepers: those affected are excluded from the church, the mosque and from community meetings; Children and young people are no longer allowed to go to school; it becomes impossible for them to get an education; nobody wants to marry into the affected families. Thus, those affected are often urged to lead a life of beggars, some even starve to death. Podoconiosis is often a "hidden disease" as families keep it hidden to avoid community shame. Having also received rejection from the government health service, they are trapped in their dilemma with no prospect of a solution. Without help, they are predestined to become the poorest of the poor.

Prevention and treatment

The primary prevention (= avoidance of the disease) consists above all in wearing socks and protective, sturdy shoes, which are best made of sturdy leather. Secondary prevention (= preventing the progression of the disease) includes:

• the training of those affected in simple but strict hygiene measures
• washing your feet every day with soap and water
• applying antiseptics and skin cream
• the consistent wearing of closed shoes.

Compression bandages also lead to a continuous improvement in symptoms. These measures require lifelong compliance by the patient. Tertiary prevention is equivalent to surgical therapy (shaving operation) and is rarely used.

history

The clinical picture has been known for over 1000 years, but it was not recognized until the end of the 19th century that it was a geochemical, non-filarial elephantiasis, which must be related to walking barefoot. Podoconiosis was listed unspecifically as non-filarial lymphedema in the medical literature until 2011.

literature

• Pietro Nenoff, Jan Christoph Simon, Grace K. Muylowa, Gail Davey: Podoconiosis as a non-filarial, geochemically caused elephantiasis - a forgotten tropical disease? Journal of the German Dermatological Society, Berlin 2009, p. 1-7 .

Individual evidence

1. ↑ ^{a b} Nenoff: Podoconiosis as a non-filarial, geochemically caused elephantiasis - a forgotten tropical disease? (PDF) In: Journal of the German Dermatological Society . 2009, pp. 1–7 , accessed November 26, 2014 . 
2. ↑ ^{a b c d} Podoconiosis: endemic non-filarial elephantiasis. In: who.int. Retrieved November 26, 2014 . 

This article is about a health issue. It is not used for self-diagnosis and does not replace a diagnosis by a doctor. Please note the information on health issues !