A Fungal Infection Not Caused By A WormKinzie Lorence AbstractIt is estimated that 10% to 15% of the populationwill be infected by a dermatophyte at some point in their lives, thus makingthis a group of diseases with great public health importance. The treatment ofdermatophytes accumulates an estimate of over 500 million dollars a yearworldwide. Ringworm is a common fungal infection of the skin and is not dueto a worm.
Tinea is the medical term for ringworm. This fungal disease is namedfor the site of the body where the infection occurs. Types of ringworm include tinea corporis, tinea capitis, tinea pedis (“athlete’sfoot”), and tinea cruris (“jock itch”). Ringworm normallycauses a scaly, crusted rash that may appear as round, red patcheson the skin. Ringworm may also cause patches of hair loss or scaling on the scalp, itching, and blister-likelesions.
Ringworm is contagious and can be passed from person toperson but can be successfully treated with antifungal medications used eithertopically or orally. Ringwormis a highly contagious fungal infection but is not dangerous. IntroductionRingworm is acommon fungal infection of the skin and is not caused by a worm. The medicalterm for ringworm is tinea. Tinea is the Latin name for a growing worm.
This fungaldisease is named for the site of the body where the infection occurs. Typesof ringworm include tinea corporis, tinea capitis, tinea pedis or athlete’sfoot, and tinea cruris or jock itch. Ringworm causes a scaly, crusted patchthat may appear as round, red patches on the skin. Ringworm may also causepatches of hair loss or scaling on the scalp, itching, and blister-likelesions. Ringworm occurs in people of all ages but is most common in childrenand 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 doare called dermatophytes, which means skin fungi. An infection with these fungiis known as Dermatophytosis. Skin fungi can only live on the dead layer ofkeratin protein on top of the skin and rarely invade deeper into the body. Theyalso cannot live on mucous membranes such as those of the mouth or vagina. TheAmerican Academy of Dermatology estimates that 10-20% of the population isaffected by dermatophytes. Dermatophytesare the reason for most of the common fungal infections in the world and are presenton all continents, except Antarctica. TypesThere are manydifferent types of ringworm.
The first is Tineabarbae which is ringworm of the bearded area of the face and neck. Thisproduces swelling and crusting which comes along with itching and sometimesloss of hair. The second type isTinea capitis which is ringworm ofthe scalp. This specific type most commonly affects children in late childhoodor adolescence. This prevalence is due to the absence of sebum secretion andcolonization which reduce the ability of the scalp to protect itself frominfection by these dermatophytes. This type of ringworm is mostly spread inschools and appears as scalp scaling resulting in bald spots. It is most commonlyfound in developing countries. Another type ofringworm is Tinea corporis which iswhen the fungus affects the skin of the body.
This type often produces roundsports like the classic ringworm. It starts out with red, scaly areas on theskin that may be slightly raised then as the condition worsens, the spots beginto form a ring shape. The ring has an active outer border as they slowly growand advance. The next type ofringworm is Tinea cruris which istinea of the groin, or jock itch. This type of ringworm has a reddish-browncolor and travels from the folds of the groin down onto one or both of thethighs.
Another type is tinea facie which is ringworm on the face except for theareas of the beard. On the face, the ringworm is rarely ring-shaped, it justcauses scaly red patches with indistinct edges. Tinea manus is ringworm that involvesthe hands, particularly the palms and the spaces between the fingers. It mostoften causes thickening of the skin on both hands.
Tinea manus is oftenaccompanied by tinea pedis which is ringworm of the feet. Tinea pedis orathlete’s foot can cause scaling and inflammation along with an itching orburning irritation in between the toes, especially between the fourth and fifthtoes. This type also produces thickening on the heels and soles of the feet. Tinea pedis is a very common skindisorder. It is the most common out of all fungal infections and is the mostpersistent. It is rare before adolescence and may occur in association withother fungal skin infections. The last type ofringworm is Tinea unguium, oronychomycosis, which is the fungal infection that makes your fingernails ortoenails yellow, thick, and crumbly. 98.
2% of patients with this are adult orelderly which is a result of the reduction in nail growth rate and theincreased likelihood of trauma in these age ranges. DiagnosisA proper diagnosisis the best thing for a successful treatment. These fungi sometimes produce arash or round scaly spots on the skin but many do not. On the other hand, manyround 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 animalsand only sometimes are found on human skin. Often thediagnosis of ringworm is obvious from its location and appearance but if not, aphysical examination needs to be taken of the affected skin, along with anevaluation of skin scrapings under the microscope, and a culture test, allwhich can help healthcare professionals make the appropriate diagnosis anddistinctions from other conditions. If the diagnosis is still unclear, apotassium hydroxide preparation of the skin scraping can be reviewed. It isimportant to distinguish ringworm of the body from other skin conditions thatmay appear similar to ringworm.
It is easy forinexperienced clinicians to overlook the diagnosis. For example, there are fourtypes of clinical appearances of scalp ringworm, grey type, black dot, kerion,and diffuse pustules. Grey type is circular patches of alopecia with markedscaling. The black dot is swollen stubs of broken off hairs that are visiblewithin the patch of alopecia. Kerion is when localized swelling occurs due toan aggressive inflammatory response in the organism. The diffuse scale is whenthis particular form looks like dandruff but with a widespread scale throughoutscalp that can be covered up with hair oils.
For a doctorto confirm the diagnosis of scalp ringworm, they use a woods light. The greenish fluorescence color that is seen under thelight is due to an ectothrix infection of hairs, which is when the fungalspores form a sheath on the outside of the hair. Treatment & ManagementRingworm is very contagiousand can be passed from person to person, called anthropophilic, by contact withinfected skin areas or by sharing combs, brushes, or other personal care itemssuch as clothing. It is also possible to become infected with ringworm aftercoming in contact with locker room or pool surfaces. Ringworm can also bepassed from an animal to a person called zoophilic, or from the soil to aperson called geophilic. It is very common to have multiple different areas ofringworm at once on the body.
Heat and moisture help fungi grow and thrivewhich makes them more commonly found in skin folds such as those in the groinand between the toes. Ringworm can besuccessfully treated with antifungal medications used either topically withexternal applications or systemically with oral medications. Home remediescannot cure ringworm.
Topical treatment for ringworm is when the fungus affectsthe skin of the body or the groin and can be treated with antifungal creams tohelp 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 asover-the-counter preparations. Systemic treatmentfor ringworm is used when fungal infections do not respond well to externalapplications. Some examples include scalp fungus and fungus of the nails. Innail infections and infections caused by zoophilic dermatophytes mainly leadingto the development of tinea capitis and corporis, the usual therapy issystemic. To penetrate these areas oral medications can be used as well as forparticularly severe or extensive diseases. An idealantifungal drug should have a broad spectrum of fungicidal activity and notcause toxicity to the host.
Currently, antibiotics and antifungals represent asmall 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. GeneticsThe dermatophyte genomes are highly collinear yetcontain gene family expansions not found in other human-associated fungi. Despitedifferences in mating ability, genes involved in mating and meiosis areconserved across species, which suggests that the possibility of cryptic matingmight occur in species where it has not been previously detected.
These genomeanalyses identify gene families that are important to our understanding of howdermatophytes cause chronic infections, how they interact with epithelialcells, and how they respond to the host immune response. These genome sequencesprovide insight and a strong foundation for future work in understanding howdermatophytes cause disease. ImmunityThe diseaseprogress is greatly influenced by the host response to the dermatophyte infection.This resistance may vary both in degree and duration, depending upon severalfactors including the species or strain of dermatophyte, the host, and the siteof infection. The zoophilic species are known to cause more inflammatoryinfections which heal spontaneously and result in relative resistance toreinfection. The anthropophillic species results in less resistance toreinfection because it usually causes more chronic, less circumscribedinfections.Complete immunityis rare but may occur at the infection site.
The reinfection of the previouslyinfected site is of shorter duration and shows less inflammation. A dermatophyteinfection in humans results in relative resistance to subsequent infection. Inhumans, increased resistance usually follows the severe inflammatory forms ofinfection such as Kerion formation, usually caused by zoophilic species butdoes not always follow the more chronic infections caused by anthropophilicspecies. PetsRingworm can alsoaffect dogs and cats, and may transmit the fungal infection to humans. Owning apet can have health, emotional, and social benefits, but pets can also serve asa source of zoonotic pathogens.
A regional survey reported more than 75% ofhouseholds having close intimate interactions with their pets like sleeping inthe same beds and face licking. People may acquire pet-associated zoonoticinfections through bites, scratches, or other direct contacts of the skin ormucous membranes with animals such as the animal’s saliva, urine, and otherbody fluid secretions. If a pet has signs of ringworm, typically bald spots ontheir bodies, you should avoid touching that animal. You should always washyour hands after touching pets to avoid the spread of any fungal infections.
Based on thestudies, young children less than 5 years old and older adults over 65 yearsold, other patients who are immunocompromised, and women who are pregnant areat increased risk for zoonotic diseases, their disease may be more severe, theymay have symptoms for a longer duration, or may have more severe complicationsthan other patients would have. Children between3-5 years old and some people with developmental disabilities may havesuboptimal hygiene practices or higher risk contacts with animals that furtherincrease risk. Dermatophytes most commonly come from cats and have a highincidence rate but a low severity rate. Severe disease is uncommon inimmunocompetent patients, but infections that are more distributed can occur. Forpatients who are immunocompetent, not pregnant, and between the ages of 5 and64 years of age, the risk of pet-associated disease is small. ConclusionRingworm is not dangerous but causes greatinconvenience to those infected by this fungus. 10% to 15% of the populationwill be infected by a dermatophyte at some point in their lives. Myyounger sister who is 14 has had ringworm for a few years now and cannot seemto 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 ofringworm she has, how to treat her specific type, and why this keepsreoccurring for her. ReferencesFuller, L C. “Diagnosis andmanagement of scalp ringworm.” The BMJ, British Medical Journal PublishingGroup, 19 Apr.
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