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A short story: " Recently, after a Microbiology class on fungi, I was approached by one of my students, who asked me if I had heard of a disease "that affects young blacks", as the symptoms and features that we discussed in class reminded her of her childhood days, when she and her brother used to suffer from some kind of infection of a scalp. Her mum used to refer to it as "something that sounds like: tethes, tethers or tethis". I told her that although I think it is probably one of the dermatophytic infections, like tinea capitis, I have never heard of the names she mentioned, so I was going to do some research to try and find out a bit more about it and get back to her. After searching the Internet under "the sound like names" and having no luck in my search, a couple of days later I thought of asking a friend and a neighbor of mine if he had heard of this disease. He happened to recognize the names as referred by his mum, but he also didn't know its "proper" name. He had an idea though. He called his mum in W. Virginia, she new what hi was talking about but could not remember the medical name, so she called her friend and a doctor and promised to call back. So after all this endeavor here is my answer."

Dr. Keti:

Tinea capitis: is a fungal infection of the scalp hair, that can be caused by any species of either Trichophyton or Microsporum. Although primarily affecting children between the ages of three and seven years of age, and mostly blacks, tinea capitis also occurs in adults and afflicts women more commonly than men. Three groups of dermatophytes cause tinea capitis: endothrix fungus, ectothrix fungus, and favus. dermatology.cdlib.org

Etiology:Cause
a.
Trichophyton tonsurans (T. tonsurans) is the most common cause of tinea capitis in the United States (2) In urban populations, large family size, crowded living conditions, and low socioeconomic status may contribute to an increased incidence of tinea capitis. Others can be acquired from animals.
During epidemics, it may affect 20% of susceptible children. It can be seen on hair stubs and has been known to remain alive for up to 2 years in the proper environment.
Breakage of hairs at the roots causes the appearance referred to as "black-dot" tinea capitis. T. tonsurans belongs to the endothrix group of infections and T. tonsurans does not fluoresce when examined with a Wood's lamp. (Wood's lamp is a light that uses long wave ultraviolet light.) When an area of scalp that is infected with tinea is viewed under a Wood's light, the fungus glows (fluoresces).
In the form of hair infection known as endothrix the infection begins by penetration of the hair, and the organism then grows up the interior main shaft of the hair where it fragments into arthroconidia.
In the form of hair infection known as ectothrix (ecto:outside), the infection begins as in endothrix, but it then extends back out through the hair cuticle (the outer wall of the hair) and forms a mass of arthroconidia both within and around the hair shaft. A typical causative agent in this case is Microsporum canis

b. Microsporum canis is the most common dermatophyte arising from dogs and cats www.doctorfungus.org/mycoses/
Arthroconidia in the shafts cause the hairs to become brittle, the hairs break at the surface of the scalp, the broken hairs that remain below the surface of the scalp give the appearance of black dots in the area of hair loss (2)

Symptoms: In the scalp, fungal infections often form circular (ringworm), scaly, with a raised edge inflamed patches and with a variable amount of redness.
Infection spreads easily from person to person (2) through combs, brushes, caps, pillowcases, cloth chairs, and other inanimate objects. Others can be acquired from animals. Microsporum canis is the most common dermatophyte arising from animals, specifically dogs and cats.

Some patients also have inflammatory lesions, such as pustules, abscesses, and kerions. Kerions are discrete, purulent, boggy, tender masses that are often related to cervical lymphadenopathy. Inflammatory tinea is often caused by zoophilic or geophilic organisms. For more info click on the links bellow: References

Conditions that Resemble Tinea capitis- Diferential Diagnosis:
Scalp conditions that resemble tinea capitis include

Diagnosis and Treatment:The diagnosis of tinea capitis is best confirmed by microscopic examination of a potassium hydroxide preparation of scalp scrapings and broken hairs that demonstrates chains of arthrospores inside hair shafts. Reference(3)

Treatment with ketonconazole 2% shampoo, or 2.5% selenium sulfide shampoo and topical antifungal creams can decrease scaling, but prompt recurrence is common because these products do not reach deeply enough into the hair follicle to eradicate the fungus. Family members should be examined and treated if diagnostic tests are positive. Ringworm in the scalp, however, usually requires oral medications. There are several oral agents that can cure this infection. Griseofulvin (Fulvicin), which has been the standard treatment for this scalp ringworm, is given daily for four to six weeks or longer.(1)


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