micro lab sheet # 3 - Ruaa Rawa Khairi

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micro lab sheet # 3 - Ruaa Rawa Khairi

Post by Shadi Jarrar on 15/2/2011, 7:53 pm

بسم الله الرحمن الرحيم




Retain back to our topic related to the superficial mycosis we have already mention that we have types of filaments fungi known as dermatophytes
Causing dermatophytosis OR superficial fungal infections related to the surface of our body in relation to skin, hair and nails.

We have mentioned these types of dermatophates are widely distributed in the nature in the form of spores or small filaments, these can be easily
Attached to our body surface, might under certain conditions causing superficial infection especially in the keratinized layer especially in association with dead skin tissue( As you know our skin always eliminate the dryness of the tissue and these can if not removed the might be a good source of nutrients for these dermatophytes.

The first type and the very common one of dermatophytes related to any part of our skin body mainly in the form of the tinea corporis, tinea in relation to type of fungal infection due to the fact that it is always recognized by the change in color of the skin it might be associated with advanced damage to the surface of epidermis and dermis recognized by irritation and in the form of allergic reaction, Inflammation may be recognized in association of bacteria and this can be recognized in the form of macular lesion or circular lesion, Some of these can be treated with topical anti-fungal drugs, Other can be disappears without any treatment it depends on the type of dermatophytes.

We mentioned from these tinea there is versicolor in certain stress condition and change in the hormonal secretion or exposing to sun light for long time it might also associated with cool temperature or heat temperature etc..

Many causative agents, Causative agents in fact it is type of yeast related to some extent to the filaments, fungi in causing the infection but these yeast are special type called lipophilic due to the fact that lopiphilic yeast requires certain amount of fatty acid to be increased in number and to produce infection.

Second type: Tinea capitis related to children especially with Tinea unguium
In relation to nails
Association with tinea unguim we have a very common type of tinea called Tinea pedis in relation to any part of nails of our foot or might be associated with any part of the feet (any part of the feet might be adapt), it can starts with nails of the foot or might be in the interdigital spaces between foot fingers and later might cover all the skin of the foot.
In the beginning you might recognize presence of only small damage within the interdigital spaces or the nails and later you might recognize more peeling ( ( تقشر due to the damage the surface of the Epidermis and this type of tinea pedis is very common in all males and females especially if they wear the shoes for a very long time (all the day) or they were very active (walking a lot or doing sport)
where this heat in the presence of small spores or filaments of tinea pedis fungi easily can attached firmly and later begin to produce damage, Usually tinea pedis recognize mainly in adults, children Rarely develop tinea pedis

Why persons wearing shoes for long time and active persons are more susceptible to tinea pedis infection?
Answer: Due to accumulation of heat in the foot where this heat in the foot

0Wearing the shoes for long period this lead to the following:
1) Accumulation of Heat, Molts (عفـــــــن)
2) Presence of fatty acid secretion or other secretions from the sweating might contribute for the developing of these infections.

Using the share shower especially in hotels and sport facilities might also enhance the infection from one person to another due to the fact that these spores from infected person remain in floor of the shower and so easily the second person will be infected And so on.

The only way to reduce the incidence of tinea pedis to do the following:
1- To try always to have your foot dry (dryness of the foot might be accomplished by exposing your foot to the air and some light at least few hours per day).
2- Try always if you recognize the begging of the peeling in the interdigital space or any part of the foot to use at least normal powder to decrease the amount of moist or to use special anti-fungal powder (everyday in the morning and evening), to prevent the spread of the infection.

It is not easy to get rid of tinea pedis. Once tinea pedis has established in any person it will become chronic and no type of drugs can remove the presence of tinea pedis.

NOTE: 50% of the population in most countries including Jordan has at least one type of pedis whether in nails or interdigital spaces, So as you see it is widely distributed in all communities and countries, The only way to be free of this type of disease to walk without shoes.

Especially oral candidiasis, we will introduce the term candida and the variation of Candida infections in the humans.

Candida: it is part of yeast and yeast as already mentioned divided
Obligated pathogen

Opportunists pathogen

Now in relation to Candida it is part of our normal body flora always associated with mucus in any part of the body (oral cavity to some extent to the throat, intestinal cavity as well as genital tract especially vagina), Under normal condition few numbers of caninda can be found So you have to appreciate that the Candida is present always in few numbers in our oral cavity, intestinal cavity as well as in the vagina.

IF there is a change in the PH of oral cavity or following especially using of anti-microbial drugs ,As you know the anti-microbial drugs effect large numbers of our bacterial normal flora an example in our oral cavity we have around one hundreds type of bacteria aerobe or anaerobe and these bacteria contribute for our normal body function especially in the oral cavity where some of these bacterial flora produce certain amount of end product especially inorganic compound and these compound to some extent suppress growth of pathogen whether bacteria or yeast.

Generally yeast prefer to grow at lower PH than bacteria so PH in our oral cavity must range ( 7-7.2 ) , if there is change in the bacterial normal flora and there is decrease in PH than you have to expect the yeast especially Candida will increase in number,
SO as u see there is oral cavity biological equilibrium.

Any decrease in the presence of our normal bacterial flora (whether facultative aerobes or anaerobes) this means that the result will be increase in the number of yeast cells especially the oral cavity and so these yeast cells following increase in the number begin adapt our oral mucosa and to produce form of infection.

The term candidiasis in relation to any disease related to any body organ it can be applies to oral candidiasis, pharyngeal caindidiasis, lung candidiasis or systemic candidiasis.

IN some certain conditions the Candida might manage to produce invasive infection, Invasive infection means to reach the blood stream especially in certain condition and produce candidaemia, and once this Candida reach the blood stream the patient will be very difficult to treat… NOT like the Condition with bacteremia where it is easily to response by the presence of the immune response and the use of the anti-microbial drugs, In Candida the immune response is weak (it is not so intense) , so candidemia often result in the death of the infected person ,Fortunately Candidiasis not easily to developed in blood stream only under special condition ( for example if the person under immunodeficiency like lymphoma. Leukemia) As well as can be recognized in new born baby which we called them neonates
Keep in mind healthy person rarely developed cadidaemia.

Under the term Candida we have a group of yeast cells which has certain specific conditions, these conditions related in fact to change in the morphology of these cells, yeast under normal condition found only as ova cells and spherical cells where in relation to the pathological condition or virulence factor related to these Candida often the first stage of the infection begin by production of what we called pseudohyphea these are type of filaments, these filaments begin to invade the superficial mucosal cells and begin to establish and produce form of inflammatory reaction this inflammatory reaction is not so sever like with bacterial infection , fungal infections not associated with pus cells but associated mainly with irritation and erythema this is the first stage of the infection and these cells once increase in number produce like a cover over the oral mucosa.

The infection can begin in floor of the tongue or it can in association with the gum (recognize the presence of whitish color cover the surface of the tongue or the tongue + gum) this whitish color is at the beginning there is no pain but there might be associated with pain especially in children, it can cover all over the oral cavity mucosa.
Remember: the whitish color due to the pseudohyphae.
Keep in mind you have not to try to remove the cover by using any instruments, if you try to remove this can lead to bleeding and even the death of the person especially children.

This should only treated by using anti-fungal drugs Or you have to know the underlying causes of candidiasis.

IN FACT oral candidiasis can be only observed in certain condition in relation to:
1- Using anti-microbial drugs if used more than one week (example tetracycline)
(Which kills a large number of gram –ve and +ve “aerobic or anaerobic”).
2- Immunodeficiency and diabetes in adults (diabetes type one or two)
And other underlying disease.
SO in children Candida appear because of using anti-microbial drugs almost
In adults Candida appears because of underlying disease almost (like diabetes or immunodeficiency).

Normally oral Candida remains locally, but in certain type of patients like patient with HIV (Aids) oral candidiasis might spread the:
1-throat 2-pharynx
3-larynx 4-lung

Candida thrush: can be recognized in association with the tongue (children) as well as in combination with tongue and gum (adults).

Skin Candida: especially in children might infect any part of the body|, rectum most common due to the presence in the intestinal cavity excreted with the feces and if the feces not removed it might attached (Candida) to the surface of skin (erythema, peeling and sever inflammation developed) this should be treated without any delay especially if there are bacterial infection also).

Vaginal candidiasis: often ????? activation in the mucosa of ladies due to secretion of the female hormones and this resulted in some changes of PH of vagina. Normally vagina like oral cavity vagina has it is own bacterial normal flora whether facultative aerobic or anaerobic including dephteriods bacilli, bacteriods, clausteredia and other types of spore forming bacteria.
All of these found in few numbers and during especially sexual contact or pregnancy there will be change in the PH and this change of PH enhance the Candida multiplication there will be increase in Candida number producing candidiasis to the vagina ……..this will lead to the developing of
What we call vaginal discharge, Under the term of vaginal discharge means we have already a fluid discharge associated with presence of number of epitheliod cells, sticky materials, as well as the presence of Candida.
This vaginal discharge might be recognized in sexual transmitted disease whether true sexually transmitted agents like niesseria conorrhia or non-specific caused by mycoplasma, Chlamydia and other organisms.

In relation to vaginal discharge Candida recognized during in fact presence of watery discharge and certain smell related to the fermentation production So we will recognize acid odor (due to fermentation of sugar) and as we know there is no pus cells because it is not inflammation it is more related to irritations peeling of vaginal mucosa and produce itching during urination (burning sensation) exactly like urinary tract infection. while in other bacterial vaginal discharge there is no odor and associated with large number of pus cells.

This type of vaginal candidiasis is so common there is no single lady has not experience vaginal candidiasis especially in association with pregnancy she will exposed at least each few months or years to vaginal candidiasis.

It can be mild, acute, sever, chronic and it depends also on the presence of underlying disease.
Vaginal discharge increase with 1-the use of anti-microbial drugs
2- Hormonal treatment 3- pregnancy

The only way to relieve the presence of vaginal discharge is to use topical anti-fungal drugs as well as sometimes we need to know if there is another underlying causes leading to vaginal Candida

Vaginal candidiasis increase with the aging until menopause it will be less.

In general to conclude about the developing of the candidiasis common risk factor in relation to candidiasis (whether oral or intestinal)

1- Use of wide spectrum of antibiotics especially long time of use
2- Use of any type of oral steroids (hormones) for long time
3- Diabetes (type one or two)
4- Wearing of denture this can contribute in developing of candidiasis
WHY? Because denture made from plastic materials this produce irritation to the oral mucosa allow the food to accumulated and in the presence of yeast it will ferment the sugar.

5-Any type immunodeficiency (leukemia , especially malignancy of lung and oral cavity)
6- Presence of HIV infection.
7- Extensive radiation for treatment or diagnostic cause
8- Uses of anti-cancer drugs, since these drugs produce immunodeficiency.
9- Organ transplantation (because in organ transplantation produce immuno-supression.

Features of Candida stomatitis: patient who wear dentures are often susceptible to develop this type of Candida.

As we mentioned the dentures will contributes to oral irritation, it is also associated with developing of what we call xerostomia of the patient’s oral cavity (the oral cavity become dry), dryness is due to change in the PH and this change result will result in change of the plaque accumulation inside patient mouth, plaques consist of many types of organic compound and bacteria these contribute indirectly for developing of features of stomatitis

*More dangerous if this Candida stomatitis or Candida oral thrush
Disseminated to the larynx it might be so sever and produce infection.

Back to the types of Candida: as we know we have many types of Candida species some are important and common species other are less

We will concentrate on the following:

. Candida albicans: associated with (50-70) % of all candidiasis whether from oral, intestinal or vaginal discharge.
. Candida glabrata, tropicalis, Krusei.

Why we need to know Candida species?
Answer: Generally Candida albicans is susceptible to the most types of anti-fungal drugs, there is anti-fungal drug called fluconazole and it is the most one use in treatment of Candida , Candida glabrata and krusei resistible to the anti-fungal drugs especially fluconazole where as Candida albicans and Candida tropicals are susceptible to fluconazole.

Remember: Candida glabrata and Candida krusei develop Resistance
To fluconazole.

Generally infection can be divided into two types:
1- Exogenous infection: the source of the infection originated from outside the human body acquired for example from environmental inhalation or from food.
2- Endogenous infection: is related to the presence of types of microorganisms whether bacteria or fungi as in our case in oral candidiasis ( where they were in few number under normal condition)

So all types of Candida followed road of Endogenous infection (not acquired from outside). Only in relation to hospitalized patients might develop candidiasis following contamination

Nosocomial: hospital acquired infection.


Done by: Ruaa Rawa Khairi
Lec No.: 3
Date of the lec: 8/10/2011

Shadi Jarrar
مشرف عام

عدد المساهمات : 997
النشاط : 12
تاريخ التسجيل : 2009-08-28
العمر : 27
الموقع : Amman-Jordan


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