micro sheet # 18 - Noor khammash

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micro sheet # 18 - Noor khammash

Post by Shadi Jarrar on 21/4/2011, 4:28 am

Lecture's outline:

بسم الله الرحمن الرحيم

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http://www.4shared.com/document/khmGlntk/micronoorJUDe.html
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• Human herpes viruses 6 and 7.
• Human herpes virus 8.
• Human papilloma viruses.


Human herpes viruses 6 and 7:

Here in relation to herpes 6 and 7 despite the fact that these are two types of viruses, they are very closely related (though herpes 7 is less harmful):
 Both infect same type of cells which is CD4 T cells (helper T cells).
 Both can be transmitted via upper respiratory tract as well as via blood stream and might be associated with presence of asymptomatic infection.
 Both are related genetically to HCMV (Human cytomegalovirus)

You might be infected, without any signs or symptoms in relation to these viruses but later these viruses might develop into very dangerous types of diseases especially in relation to lymph system.

Rosella infant disease (rose rash of infants):

Herpes 6 and 7 might cause a type of disease known as rosella infant disease also known as roseola infantum. (Rose rash of infants)

Roseola infantum means the following:
 A sort of infection in the upper respiratory tract might be characterized like any other retro virus.
 This infection might be very simple like sore throat, simple tonsillitis, pharyngitis etc in association of fever.
 And may be complicated with lymph adenopathy.
 In addition, there will be a developing of special skin rashes, red smooth flat spots over the face and trunk of children.(maculopapular rash)
 It might be associated with what we call neurological disease. (In very few cases of immunodeficiency, neurological complications may present, either as aseptic meningitis or encephalitis)

In very rare cases, the virus reaches the liver and produces liver cirrhosis, hepatitis exactly like the other hepatitis viruses ,this is a rare complication and it might occur in less than 1% of the infected children.

As for the majority of infected infants/children, this disease is:
1. Asymptomatic, or
2. Developed into poor mild respiratory tract infection, with poor symptoms.

Now following the infection , this has been proven, there will be a developing of special antibodies and these specific antibodies to some extent prevent the reoccurrence of the disease.

These types of viruses disseminate in a form of outbreaks in families, for example when there is only a single child infected with this virus we have to expect other children in contact with him to become infected, (through oropharyngeal secretions and saliva).
The developing of the symptoms and signs is believed to be related to rhinovirus and para influenza virus!

Herpesvirus 8:

 A very interesting type of virus which has been discovered accidentally in relation to AIDS cases.
 Herpesvirus 8 virus DNA is partially homologous to EBV DNA.
 This herpes virus has been classified as 8 and known now as sarcoma kaposi herb virus which causes:

• Cancers that develops in connective tissue affects the fibrous tissue below skin surface as well as mucous membrane and might be associated with the mouth and nose and anus.
• In particular among homosexual.
• This type of disease if it's not treated by surgical means or by other means, might be resulted in developing hurtful sever damage in the infected organs.
• Might spread to the internal organs and result in the death of the patient.


 Where in California 1983, they had recognized for the first time the presence of a disease in relation to the rectum of infected people and at that time they had no idea about the causative agent of the AIDS which is HIV.
 Few examinations in public health and family center found at the same time among young people many cases related to type of malignancy in the rectum (a Type of sarcoma=AIDS).
 At the same time they found an uncommon tumor in old adult, mainly Jewish and Mediterranean populations. (KS).
 The conclusion is KS is caused by an unknown sexually transmitted virus that rarely causes tumors unless the host becomes immunosuppressed , as in AIDS.


In relation to dentistry, we might recognize some cases in association with the gum of the patient, and this sever damage of the mucosa of the gum indicates presence of sever damage in tissues and might be associated with inflammatory reaction. This infection is easily recognized by the change of gum's color from red to bluish red. (Same lesions with same colors might be presented on the affected epidermis and dermis of the skin and without any presence of any inflammation).

This virus might spread to the lymph system, particularly type B cells, and results in B cell lymphoma in patient with AIDS.

This type of viral infection is related mainly to patient suffering from AIDS, and treatment can be done by surgical means, and by using of radio therapy.
Using specific radiation as well as drugs can be useful. But in general it's not easy to cure patients suffering from what we call secondary infection with more damage of the infected tissue.


Papilloma viruses:

General characteristics of this group of viruses:
 Double stranded DNA viruses.
 Associated with a large number of capsomers(72 capsomers and might be increased one or three).
 Papilloma viruses are widely distributed in relation to human animals and birds.
 Rarely animal papilloma viruses produce infection to human but there is one case in relation to skin.

HPV-human papilloma viruses:

 Generally HPV are composed of 200 types, classified according to the homology of their genome and glycoproteins.
 By using molecular techniques we can differentiate between different types of HBV and categorize them according to their potential of causing malignancy into low, intermediate and high.
 HBV can be divided into:
1. HBV cause cutaneous warts: are associated with skin infection and widely distributed in comparison to other types.
2. HBV cause mucocotanuoes lesions: can be found without any presence of disease or infection of importance. The problem with these viruses is their association of developing a malignant cancer. (Especially cervical cancers).
3. HBV related to oral cavity.
Generally viral DNA can be attached to the epithelial basal cells, and the virus genome (as the infectious part of the virus) can be found in other cellular layers of the epithelium, and it can be easily recognized and isolated. Then during replication of virus, some of the viral DNA will be integrated within the host epidermal cells, and become as part of the chromosome, and under certain condition it's activated and established into the stratified epithelium of the skin following the mucous membrane and resulted in developing a benign type of warts on skin, in mucosa or in relation to genital mucosa and might be without any pain or damage.

In relation to skin, HBV might be only resulted in developing of warts and that is recognized at the beginning by the presence of severe change in the color of spot on the skin. Later these spot is associated with hyperkeratosis which indicates the presence of warts.

In some times, some of these warts may disappear. Like you recognize the presence of small colored (mostly brown) warts on your skin, fingers and face for few weeks or months and later without any treatment they may disappear without leaving any damage. So not all of these HPV are associated with developing of what we say malignant malignancy.

Now in relation to HPV, almost 30 types are classified as infectious and involved with presence of warts and most of them can be easily transmitted by close contact like hand shaking. Hand shaking might be enough to disseminate the virus from one person to another. As for oral cavity infection caused by HPV it is spread by the kissing act. And one of most important way is by sexual contact. Why?
For the lack of signs and symptoms.
as some of HPV can be found on the extra genitalia(as a part of the natural viral flora) without the presence of warts, lesion etc. so the infected person might transmit the infection to another, who is by chance more susceptible to infection due to his/her immune status.


HBV cause cutaneous warts

Most common HPV that are related to skin/cuatanuos infection are divided into:
 "Common skin wart" that is known as (Verruca vulgaris): this type of warts is caused by type 2, 4, 7 HPV. Easily spread by skin contact (hand shaking).

 "Deep planter wart" in relation to feet, (Verruca plantaris): this type is caused by types 1 and 4 HBV. Person becomes infected by the entrance of infectious particles through broken skin in his feet.

 "Flat wart": is caused by types 3 and 10.

The majority of these types with a percentage of 99.9% are not cancerous. Are only associated with cosmetic eruption of warts. These cosmetic warts are not dangerous, and treatable.

Our body response to the entrance of these viruses by production of two types of immune responses:
1. Humoral specific antibodies, usually with no importance.
2. Cell mediated immunity which is more important in preventing the progression of benign lesion into malignancy.

Persistent and recurrent warts increased with immunodeficiency.
In relation to oral HPV and genital HPV more malignancy might be associated with these types.

There are types only related to skin and can't produce any form of infection to oral mucosa and genital mucosa.

On the other hand there are other types of viruses that can cause harm to skin as well as to oral and genital mucosa, but still specialized to cause infection of the mucosa.

HBV cause mucocotanuoes lesions

Genital HBV infections are very common and mostly associated with sexually transmitted disease such as Gonorrhea (caused by Neisseria gonorrhoeae),
Syphilis (caused by Treponema pallidum), Chlamydia (Chlamydia trachomatis) and other STD caused by Mycoplasma genitalium.

In relation to cervical warts which are known as (flat condyloma) as well as angogenital warts (condylomata accuminata) (very common in population whether in our country or others), mostly are not associated of developing of any type of malignancy, since they are caused by types 6 and 11 HBV.
 Again and again types 6 and 11 are considered of low risk of malignancy, and rarely their infections progress into any type of malignancy.
 Type 6 and 11 cause 90% of human genital infection
 The 10% of human genital infections are caused by types 16 and 18.
 Types 16 and 18 are of high risk of malignancy.

• The problem with these two types is that their infection starts as mild infection especially in young women (between 19 and twenties).
• This mild infection can't be recognized since it's asymptomatic (there is no presence if warts or any kind of lesions etc.)
• But the virus presents on the genital mucosa of the infected woman, after (6-20) years might result in developing a form of cell abnormality consequently malignancy such as a Cervical cancer.

According to the records about one million women in the world get infected each year by HBV 16 and 18, and this infection progresses into cervical cancer as a result 25% of those women die following the infection due to the lack of treatment.

So it's very important to control the presence of these two types of viruses. And this is can be done by clinical investigation by recognition of any lesion at cervix and by using the papsmear that may indicate the presence of the virus. (Not its TYPE)

Certain risk factors associated with developing of cervical cancer of women:
 Young age.
 Smoking.
 Use of immunosuppressive drugs.
 Oral contraceptive

Generally for protection from developing of a cervical cancer. Each woman must be investigated by colposcopy and it will indicate the presence of lesions.
And by taking a biopsy and examining it using the papsmear test, it may indicate the presence of abnormal cells.The second step is to identify the type of the virus.

As we said 16 and 18: highly associated with cervical adenocarcinoma which is a dangerous form of malignancy that might result in severe bleeding and later disseminate to other internal organ, and eventually cause woman death.

Here in Jordan low incidence of HPV 16 and 18 in comparison to western countries which 5% of (20-40 years aged) women are infected .

Last part of HBV related to respiratory papilloma:

Respiratory papilloma: mostly benign lesions on mucosa or respiratory tract.

Our respiratory tract might be exposed to HBV that cause infection to genital mucosa, like types 6 and 11, and less commonly 16 and 18.
They may cause respiratory and genital infection (associated together), or they can only cause respiratory infections that resides in larynx and produse laryngeal papilloma.

Laryngeal papilloma: is a serious medical condition that is rarely recognized in normal population caused by a HPV infection. Over a period of time developed papillomas, without treatment, is potentially fatal as uncontrolled growths could obstruct the airway and cause suffocation .children less than 15 years are more affected.

Squamous oral papillomas and oral hyperplasia: benign growths of the surface epithelium, found mostly on oral buccal mucosa, lips, tongue base and may spread to throat, tonsils and soft palate.
we as dentists recognizes this condition in form of oral hyperplasia (benign growth) on the gum.

As a rule any lesion in oral cavity, genital mucosa or skin: if it's presented for six months or more, it must be examined. (Especially smokers and alcohol abusers).

Lab diagnosis and treatment:

• First step in diagnosis, is taking a biopsy and using a pap smear test.
Pap smear test must be done for each married women at least once every 2-3 years.

If any atypical squamous cells or atypical glandular cells are recognized, they might lead to malignancy.

• Second step is to determine the type of HBV.

Treatment:

By cryotherpy or cryosurgery: which is the application of extreme cold to destroy abnormal or diseased tissue. we use dry ice, liquid nitrogen and salicylic acid. often this surgery prevents the complications related to HBV.
But it's known that once we find any types of cervical lesions or warts, we must expect the reoccurrence of these lesions later.

Recently there is a very potential vaccine (up to 90%) available against HBV types 16 and 18.it's recommended to use this vaccine as a sort of protection in women.(as a prophylactic procedure).



Done by: Noor khammash.
Lecture date:21st of march.

Best of luck =)
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Shadi Jarrar
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عدد المساهمات : 997
النشاط : 12
تاريخ التسجيل : 2009-08-28
العمر : 26
الموقع : Amman-Jordan

http://jude.my-rpg.com

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