Human papillomaviruses

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Transcript Human papillomaviruses

Human
Papillomaviruses
Prof. Dr Asem Shehabi
Faculty of Medicine, University of
Jordan
General Introduction
 Human Papillomaviruses (HPVs).. Small ds DNA..
Capsid,72 Capsomers with 2 surface major Proteins
(L1,L2)..Responsible for invasion, widely distributed in
nature.. Infect Human, Animals, Birds.
 Infect basal layers of squamous /columnar epithelium ..Viral
DNA multiply in nucleus of cells.. cause no cell lyses.
infectious virus DNA found in upper cell layers of
epithelium (keratinocytes) ..causes Hyperkeratosis in horny
layer.. Viral DNA can integrate in host chromosome.
 Viral infection establish in epidermis & mucous
membranes.. Mostly benign Skin Warts.. Few virus types
progress to malignant lesions..less than 0,01%.
 HPVs 200 types classified according homology of their
genomes.. Types are categorized as low, intermediate &
high risk according to their Oncogenic potential.
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 About 15 most common HPVs cause skin infections ..
Viruses found in dead & living epidermis cells..
Transmitted from one infected person to another
through direct skin contact, swimming floors, showers/
baths ..less clothes, dust particles.
 Cutaneous warts: Common types HPVs (1-8,10) grow in
keratinized epithelium.. Face, hands, feet..other body parts.
 -Common skin /oral wart (Verruca vulgaris).. Types 2,4,7
 -Deep Plantar warts (Verruca Plantaris).. Types 1,4.. Hard
grainy growths appear on soles the feet .
 -Flat Warts.. Types 3,10.. Smooth colored face, legs
fingers ..persist short / long time.
 Children are more susceptible to HPVs than adults.
 Skin HPV types are different from those that cause
malignant growths in the throat or genital area.
Warts on Skin-Toe/
Hyperkeratosis
Genital HPV-1
 Both humoral & cell-mediated immune responses develop..
Following skin infection.. Persistent & recurrent warts
increased with cell mediated immunodeficiency.
 Genital HPV infections are very common and mostly
associated with sexual contact & sexually transmitted
diseases.
 Anogenital warts/ Condylom acuminatum affect any part
of the sexual organs.. Penis, Vulva, Vagina, Cervix..
Perianal skin , common in sexually active adults.
 Types 6,11 cause 90% of benign anogenital infections..
mostly Cervical warts (Flat Condyloma/ squamous
intraepithelial neoplasia)..may affect oral cavity
Genital HPV-2
 Genital warts often occur in clusters and can be very
tiny lesion or spread into large masses in the extragenital or rectal area.. Rarely in anal colon
 HPV types 16+18 are associated with high risk of
malignancy..mostly found inside vagina & cervix.
 Most HPV genital infections occur without any symptoms
and may disappear without any treatment over few years.
Genital HPV infection sometimes persists for many years,
without causing cell abnormalities.. This mimic its present
infection & increase a woman’s risk of developing cervical
cancer.. Each year nearly 1 million women worldwide..
killing 250000 lives.
Genital HPV-3
 Increase risk factors of cervical cancer in women with
HPV infection include young age, smoking, use
immune suppressed drugs, oral contraceptive drugs,
sexually transmitted diseases.
 Precancerous HPV lesions in cervix can progress to
invasive cervical cancer.. usually takes 15–20 years
 Persistent HPV genital infections ( types 16,18) cause 70%
of cervical cancer/endocervical Adenocarcinoma in
Western countries.. Still less incidence in Jordan & most
Arab countries.. Screening should be done for every woman
using Colposcopy & Pap-smear
H
PV-4
 Respiratory Papilloma .. mostly benign lesions on mucosa
respiratory tract.. Larynx ( Laryngeal Papilloma).. Children
and adults .. May cause obstruction if not removed early as
possible ..Caused mostly by HPV types 6 & 11.. Less
types 16 & 18.. It is unknown if immunological
conditions contribute for infection.. Common among
middle age (30-50) years.
 Squamous oral papillomas & Oral Hyperplasia ..
(Types 6,11) are considered benign growths of the
surface epithelium ..The lesions found on oral mucosa,
lips, tongue base..small & large..may spread to soft palate,
throat, tonsils.. Past HPVs exposure is increasing the risk of
oral lesions.. old age, Common in association tobacco and
alcohol use.
Lab Diagnosis & Treatment
 A Pap smear test is used to detect abnormal cells in cervix ..
Atypical squamous & glandular epithelial cells .. A Pap test
is recommended at least once every 2-3 years.
 Detection of HPV DNA from suspected lesions by PCR is
more accurate and detect early infection.
 There is currently no antiviral drugs against Papillomavirus
infection.. the lesions should be removed.
 Treatment: Cryotherapy/ Cryosurgery.. Removing the
lesions does not necessary eradicate the virus completely..
reoccurrence of warts is common.
 New Vaccine is available against HPV types 16,18..
Effective up 90% and safe.
Detection and typing of common human
papillomaviruses among Jordanian patients.
S.bdour, L. AkKash, A.A> Shehabi
J Medical Virology, 2013, 85:158-63
The epidemiology of human papillomaviruses (HPVs)
genotype distribution of cutaneous warts in Jordanian
patients were studied.
A total of 200 samples were collected using skin swabs
from patients with warts attending the dermatology
clinic at the J U Hospital (2010 -2010). Another 100
control samples were taken from healthy Jordanian
with no current or previous history of warts
Methods: Wart samples collected using..DNA extraction
and sequencing was carried out using PCR with the
specific primer pair to detect HPV DNA, followed by
multiple-type-specific (Multiplex) PCR combined with
DNA sequencing.
 Results: The prevalence of HPV among Jordanian
patients tested with warts diagnosed clinically was
82% .
 Conclusion: Alpha HPV types (2, 27, 57).. are mostly
detected in Cutaneous warts of Jordanian patients
with skin warts..These types rarely associated with
malignancy.