A Fungal Infection Not Caused By A Worm
It is estimated that 10% to 15% of the population
will be infected by a dermatophyte at some point in their lives, thus making
this a group of diseases with great public health importance. The treatment of
dermatophytes accumulates an estimate of over 500 million dollars a year
worldwide. Ringworm is a common fungal infection of the skin and is not due
to a worm. Tinea is the medical term for ringworm. This fungal disease is named
for the site of the body where the infection occurs. Types of ringworm include tinea corporis, tinea capitis, tinea pedis (“athlete’s
foot”), and tinea cruris (“jock itch”). Ringworm normally
causes a scaly, crusted rash that may appear as round, red patches
on the skin. Ringworm may also cause patches of hair loss or scaling on the scalp, itching, and blister-like
lesions. Ringworm is contagious and can be passed from person to
person but can be successfully treated with antifungal medications used either
topically or orally. Ringworm
is a highly contagious fungal infection but is not dangerous.
Ringworm is a
common fungal infection of the skin and is not caused by a worm. The medical
term for ringworm is tinea. Tinea is the Latin name for a growing worm. This fungal
disease is named for the site of the body where the infection occurs. Types
of ringworm include tinea corporis, tinea capitis, tinea pedis or athlete’s
foot, and tinea cruris or jock itch. Ringworm causes a scaly, crusted patch
that may appear as round, red patches on the skin. Ringworm may also cause
patches of hair loss or scaling on the scalp, itching, and blister-like
lesions. Ringworm occurs in people of all ages but is most common in children
and most often occurs in warm, moist climates. There are many yeasts, molds,
and fungi, in the world but only a few cause skin diseases. The ones that do
are called dermatophytes, which means skin fungi. An infection with these fungi
is known as Dermatophytosis. Skin fungi can only live on the dead layer of
keratin protein on top of the skin and rarely invade deeper into the body. They
also cannot live on mucous membranes such as those of the mouth or vagina. The
American Academy of Dermatology estimates that 10-20% of the population is
affected by dermatophytes. Dermatophytes
are the reason for most of the common fungal infections in the world and are present
on all continents, except Antarctica.
There are many
different types of ringworm. The first is Tinea
barbae which is ringworm of the bearded area of the face and neck. This
produces swelling and crusting which comes along with itching and sometimes
loss of hair.
The second type is
Tinea capitis which is ringworm of
the scalp. This specific type most commonly affects children in late childhood
or adolescence. This prevalence is due to the absence of sebum secretion and
colonization which reduce the ability of the scalp to protect itself from
infection by these dermatophytes. This type of ringworm is mostly spread in
schools and appears as scalp scaling resulting in bald spots. It is most commonly
found in developing countries.
Another type of
ringworm is Tinea corporis which is
when the fungus affects the skin of the body. This type often produces round
sports like the classic ringworm. It starts out with red, scaly areas on the
skin that may be slightly raised then as the condition worsens, the spots begin
to form a ring shape. The ring has an active outer border as they slowly grow
The next type of
ringworm is Tinea cruris which is
tinea of the groin, or jock itch. This type of ringworm has a reddish-brown
color and travels from the folds of the groin down onto one or both of the
thighs. Another type is tinea facie which is ringworm on the face except for the
areas of the beard. On the face, the ringworm is rarely ring-shaped, it just
causes scaly red patches with indistinct edges.
Tinea manus is ringworm that involves
the hands, particularly the palms and the spaces between the fingers. It most
often causes thickening of the skin on both hands. Tinea manus is often
accompanied by tinea pedis which is ringworm of the feet. Tinea pedis or
athlete’s foot can cause scaling and inflammation along with an itching or
burning irritation in between the toes, especially between the fourth and fifth
toes. This type also produces thickening on the heels and soles of the feet.
Tinea pedis is a very common skin
disorder. It is the most common out of all fungal infections and is the most
persistent. It is rare before adolescence and may occur in association with
other fungal skin infections.
The last type of
ringworm is Tinea unguium, or
onychomycosis, which is the fungal infection that makes your fingernails or
toenails yellow, thick, and crumbly. 98.2% of patients with this are adult or
elderly which is a result of the reduction in nail growth rate and the
increased likelihood of trauma in these age ranges.
A proper diagnosis
is the best thing for a successful treatment. These fungi sometimes produce a
rash or round scaly spots on the skin but many do not. On the other hand, many
round red spots or rashes on the skin are not due to a fungal infection at all.
Some fungi live only on human skin, hair, or nails while others live on animals
and only sometimes are found on human skin.
diagnosis of ringworm is obvious from its location and appearance but if not, a
physical examination needs to be taken of the affected skin, along with an
evaluation of skin scrapings under the microscope, and a culture test, all
which can help healthcare professionals make the appropriate diagnosis and
distinctions from other conditions. If the diagnosis is still unclear, a
potassium hydroxide preparation of the skin scraping can be reviewed. It is
important to distinguish ringworm of the body from other skin conditions that
may appear similar to ringworm.
It is easy for
inexperienced clinicians to overlook the diagnosis. For example, there are four
types of clinical appearances of scalp ringworm, grey type, black dot, kerion,
and diffuse pustules. Grey type is circular patches of alopecia with marked
scaling. The black dot is swollen stubs of broken off hairs that are visible
within the patch of alopecia. Kerion is when localized swelling occurs due to
an aggressive inflammatory response in the organism. The diffuse scale is when
this particular form looks like dandruff but with a widespread scale throughout
scalp that can be covered up with hair oils.
For a doctor
to confirm the diagnosis of scalp ringworm, they use a woods light. The greenish fluorescence color that is seen under the
light is due to an ectothrix infection of hairs, which is when the fungal
spores form a sheath on the outside of the hair.
Treatment & Management
Ringworm is very contagious
and can be passed from person to person, called anthropophilic, by contact with
infected skin areas or by sharing combs, brushes, or other personal care items
such as clothing. It is also possible to become infected with ringworm after
coming in contact with locker room or pool surfaces. Ringworm can also be
passed from an animal to a person called zoophilic, or from the soil to a
person called geophilic. It is very common to have multiple different areas of
ringworm at once on the body. Heat and moisture help fungi grow and thrive
which makes them more commonly found in skin folds such as those in the groin
and between the toes.
Ringworm can be
successfully treated with antifungal medications used either topically with
external applications or systemically with oral medications. Home remedies
cannot cure ringworm. Topical treatment for ringworm is when the fungus affects
the skin of the body or the groin and can be treated with antifungal creams to
help clear up the condition. For treating the fungal infections of the skin,
topical medications are appropriate only for early or mild infections,
especially those caused by tinea pedis. Most antifungal creams are available as
for ringworm is used when fungal infections do not respond well to external
applications. Some examples include scalp fungus and fungus of the nails. In
nail infections and infections caused by zoophilic dermatophytes mainly leading
to the development of tinea capitis and corporis, the usual therapy is
systemic. To penetrate these areas oral medications can be used as well as for
particularly severe or extensive diseases.
antifungal drug should have a broad spectrum of fungicidal activity and not
cause toxicity to the host. Currently, antibiotics and antifungals represent a
small group of drugs which plays an important role in fungal disease control,
however, some of these antifungals have serious drawbacks such as toxicity,
fungistatic activity, or a limited spectrum of action or resistance.
The dermatophyte genomes are highly collinear yet
contain gene family expansions not found in other human-associated fungi. Despite
differences in mating ability, genes involved in mating and meiosis are
conserved across species, which suggests that the possibility of cryptic mating
might occur in species where it has not been previously detected. These genome
analyses identify gene families that are important to our understanding of how
dermatophytes cause chronic infections, how they interact with epithelial
cells, and how they respond to the host immune response. These genome sequences
provide insight and a strong foundation for future work in understanding how
dermatophytes cause disease.
progress is greatly influenced by the host response to the dermatophyte infection.
This resistance may vary both in degree and duration, depending upon several
factors including the species or strain of dermatophyte, the host, and the site
of infection. The zoophilic species are known to cause more inflammatory
infections which heal spontaneously and result in relative resistance to
reinfection. The anthropophillic species results in less resistance to
reinfection because it usually causes more chronic, less circumscribed
is rare but may occur at the infection site. The reinfection of the previously
infected site is of shorter duration and shows less inflammation. A dermatophyte
infection in humans results in relative resistance to subsequent infection. In
humans, increased resistance usually follows the severe inflammatory forms of
infection such as Kerion formation, usually caused by zoophilic species but
does not always follow the more chronic infections caused by anthropophilic
Ringworm can also
affect dogs and cats, and may transmit the fungal infection to humans. Owning a
pet can have health, emotional, and social benefits, but pets can also serve as
a source of zoonotic pathogens. A regional survey reported more than 75% of
households having close intimate interactions with their pets like sleeping in
the same beds and face licking. People may acquire pet-associated zoonotic
infections through bites, scratches, or other direct contacts of the skin or
mucous membranes with animals such as the animal’s saliva, urine, and other
body fluid secretions. If a pet has signs of ringworm, typically bald spots on
their bodies, you should avoid touching that animal. You should always wash
your hands after touching pets to avoid the spread of any fungal infections.
Based on the
studies, young children less than 5 years old and older adults over 65 years
old, other patients who are immunocompromised, and women who are pregnant are
at increased risk for zoonotic diseases, their disease may be more severe, they
may have symptoms for a longer duration, or may have more severe complications
than other patients would have.
3-5 years old and some people with developmental disabilities may have
suboptimal hygiene practices or higher risk contacts with animals that further
increase risk. Dermatophytes most commonly come from cats and have a high
incidence rate but a low severity rate. Severe disease is uncommon in
immunocompetent patients, but infections that are more distributed can occur. For
patients who are immunocompetent, not pregnant, and between the ages of 5 and
64 years of age, the risk of pet-associated disease is small.
Ringworm is not dangerous but causes great
inconvenience to those infected by this fungus. 10% to 15% of the population
will be infected by a dermatophyte at some point in their lives. My
younger sister who is 14 has had ringworm for a few years now and cannot seem
to get rid of it, which is why I chose this topic. After researching Dermatophytosis,
I feel I am more knowledgeable on how she contracted this, which type of
ringworm she has, how to treat her specific type, and why this keeps
reoccurring for her.
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