Transcript Human Herpesvirus 1

Dr. Sadeli Masria, dr., SpMK., MS.
Dept. of Microbiology
Medical Faculty, Padjadjaran University
OCULAR INFECTIONS
Ocular bacterial infections
viral
fungal
The normal eye has very
effective defenses against
infections :
- The eyelids & lashes prevent
foreign debris from striking the eye
- The eyelids wash the tears across
the cornea and cleanse the eyes
- Tears contain secretory
immunoglobulins & lysozymes that
help prevent infection
- The corneal epithelium and
collagenous tissues (Bowman’s
layer) act as strong barrier
- The eye becomes susceptible to
infection only when these defense
mechanisms are altered
INTRODUCTION
The hallmark of an ocular infection is a red eye
- The eyelid margins are red in cases of
blepharitis
- The conjunctiva are injected in bacterial and
viral conjunctivitis
- The deep blood vessels adjacent to the
cornea and sclera are dilated in cases of
iritis
- Erythema of all ocular structures
suggests a severe infection of the entire
globe and orbit
- (Such as panophthalmitis)
- The presence of edema in addition to
erythema suggest advanced infection or
inflammation
An ocular discharge is not normal :
- Watery discharge in allergies
- Serosanguineous in severe viral
conjunctivitis
- Purulent in bacterial infections
Symptoms of an ocular
infection :
- The first are a mild sensation of
foreign body, tearing and
sensitivity to sunlight
- More advanced infection causes
pain and decreases vision
OCULAR BACTERIAL
INFECTIONS
- Conjunctivitis
- Infection of the eyelids and
ocular adnexae
- Bacterial corneal ulcers
- Orbital cellulitis
Conjunctivitis
- Etiology :
- Neisseria
- Chlamydia
- Hemophilus
May cause by normal conjunctival flora
Chlamydia : Ch.trachomatis,
Ch. Pneumoniae, Ch. psittaci
- Are obligate intracellular parasite
- Multiply in the cytoplasm of their
host cells
- Known as elementary body (EB) or
reticulate body (RB)
- May be found in epithelial cells of
conjunctival scraping stain with
giemsa or fluorecent antibody
Normal conjunctival flora :
- Aerobic bacteria :
- Staphylococcus epidermidis
- Staphylococcus aureus
- Streptococcus pneumoniae
- Streptococcus sp
- Corynebacterium sp
- Micrococcus sp
- Bacillus sp
- Gram-negative rods
Staphylococcus :
Typical organisms :
- Are spherical cells, arranged in
irregular cluster
- Are gram positive, grow readily on
most bacteriologic media under
aerobic or microaerophilic conditions
- Colonies are round, smooth, raised,
glistening
Streptococcus :
Typical organisms :
- Are gram positive, individual cocci are
spherical or ovoid arranged in chain
- Grow on solid enriched media as
discoid colonies, ø 1-2 mm
Corynebacterium :
- Non-spore-forming gram positive
bacilli
- C. diphtheriae is the most important of
the group
- Grow aerobically on most ordinary
laboratory media
Normal conjunctival flora :
- Anaerobic bacteria :
- Propionibacterium acnes
- Peptostreptococcus sp
- Lactobacillus sp
- Clostridium sp
- Eubacterium sp
Normal conjunctival flora :
- Fungi :
- Candida sp
- Aspergillus sp
- Rhodotorula sp
- Viruses : adenoviruses
Clinical manifestations
Symptoms & signs of bacterial
conjuctivitis :
- Symptom : burning, itching, foreign body sensation,
pain, photophobia, tearing
- Sign :
- Preauricular node
- Purulent discharge
- Marred eyelashes
- Conjunctival injections
- Eyelids disease
- Subconjunctival hemorrhage
EPIDEMIC CONJUNCTIVITIS
PINKEYE
Characterized by an inflamed,
bright red conjunctiva with
inflammation extending into
the cornea
It is spread by direct person-toperson contact
It is no threat to eyesight
Etiological agent :
Haemophilus aegypticus
Moraxella lacunata
Haemophilus
 Gram-negative
coccobacilli
 Fastidious and require
factors X (hemin) and/or
V (NAD)
 Possess LPS in the cell
wall but produce no
apparent extracellular
toxins
 All Haemophilus species
grow more readily in an
atmosphere enriched
with CO2
Moraxella
 The mucous membranes of humans and
other warm-blooded animals
 Many species are nonpathogenic
 M lacunata can be isolated from the
eyes and may cause conjunctivitis in
humans living under conditions of poor
hygiene
 Cocci that morphologically resemble
Neisseria
Diagnosis :
Clinically in the presence of symptom and sign
laboratory diagnosis :
- Gram stain are less rewarding
- Cultures : ~ also have a poor yield
~ only 30% of patients with clinical
~ bacterial conjunctivitis harbor
~ pathogenic organisms
OPHTHALMIA
NEONATORUM
From a mother with
gonorrhea as the fetus
passes down the birth
canal. Infection does not
occur in utero
At one time about 10%
of all cases of blindness
Corneal inflammation is
the major clinical sign.
Etiological agent :
Neisseria
gonorrhoeae
Neisseriaceae
 Neisseria spp.
 􀁎Gram-negative diplococci (kidney bean,
coffee bean)
 aerobic, microaerophilic, chocolate agar
 non-motile, non-spore forming, oxidase
positive
 Acinetobacter spp.􀁎
 Kingella spp.􀁎
 Moraxella spp.
Neisseria
: N. gonorrhoeae
N. meningitidis
Typical organisms :
is a gram negative
non-motile diplococcus
individual cocci are kidney-shaped
when the organisms occur in pairs,
the concave sides are adjacent
Growth characteristic :
- Grow best under aerobic conditions
- Some will grow under anaerobic environment
- They have complex growth requirement
- In 48 hours on enriched media (Mueller-Hinton,
Thayer Martin), Neisseria form convex,
glistening, elevated, mucoid colonies, ø 1–5 mm
- The colonies are transparant or opaque non
pigmented, non hemolytic
Infection of the eyelids and
ocular adnexae
- Infection of the eyelids and ocular adnexae
(lacrimal glandm lacrimal ducts, and lacrimal
sac)
- Infection of the eyelids and adnexae produces
redness & swelling of the involved structures
- Chronic infection produces permanent changes
in the structure and may causes permanent loss
of function
The sty (hordeolum) :
- Is an acute staphylococcal abscess of the oil
secreting glands of the eyelids
- May occur on the inner lid (internal hordeolum)
when the meibomian glands are involved
- And on the outer surface of the lids (external
hordeolum) when the glands of Zeiss and Moll
are infected
- Acute localized swelling of the lid with pain
erythema
- The abscess may point through the skin of
the lids
- The conjunctiva and remainder of the eye
are usually univolved
Blepharitis (chronic low-grade
infection of oil-secreting glands
Etiology : Staphylococcus aureus
Staphylococcus epidermidis
Produces a vascularized and erythematous lid
margin with scale formation, loss of lashes,
production of white lashes, misdirection of
lashes, and deposits around the base of the
eyelashes
Dacryocystitis (infection of the
lacrimal sac)
Etiology :
- Staphylococcus aureus
- Streptococcus pneumoniae
- Hemophilus influenzae
Canaliculitis (infection of the
lacrimal ducts)
Etiology :
- Actinomyces
- (Fungi)
- Other bacteria rarely cause
canaliculitis
Bacterial corneal ulcers
Occurs after trauma to the cornea  disrupt the
epithelium  permits bacterial colonization
Etiology :
- Pseudomonas
- Stephylococcus aureus
- Streptococcus pneumoniae
- Moraxella
These organisms capable of epithelial
colonization and penetration can produce
spontaneous infection :
- Neisseria gonorrhoeae
- Corynebacterium diphtheriae
- Hemophilus
Clinical manifestations :
- The hallmark of bacterial corneal ulceration is
pus
- The stroma becomes opaque and the surface
irregular
- The underlying stroma becomes soft and
mushy; often discolored to a white, yellow or
brown color.
Laboratory diagnosis :
- The specimen (corneal scraping) must be
collect by an opthalmologist
- Microscopic examinations :
- Gram staining, acid-fast or Giemsa
- Bacterial culture
Orbital cellulitis
Is an acute inflammation of the orbital tissue
- Produced by spread of an infection from
nearby structure or distant foci
Etiology :
- Hemophilus influenzae
- Staphylococcus aureus
- Streptococcus group A
- Streptococcus pneumoniae
Clinical manifestation :
- The eye usually protrudes (proptosis)
- The lids are usually swollen shut with a
discharge
- The cornea can become exposed,
ulcerated and perforated
INCLUSION CONJUNCTIVITIS
INCLUSION BLENNORRHEA OF THE NEWBORN
SWIMMING POOL CONJUNCTIVITIS
 During the birth process, when the fetus
passes down the birth canal, it can contract
an eye infection from the mother's genital
flora.
 If Chlamydia trachomatis of a particular
serotype is obtained in this way it can
cause an inclusion conjunctivitis after a 512 day incubation period.
 Etiological agent : Chlamydia trachomatis
OCULAR LYMPHOGRANULOMA
VENEREUM
As in inclusion conjunctivitis, a fetus can contract
an eye infection by Chlamydia trachomatis
during passage down the birth canal
However, if it is of a more virulent serotype than the
strain causing inclusion conunctivitis, the
presentation can be that of ocular
lymphogranuloma venereum
This will occur 5-12 days after birth
Etiological agent : Chlamydia trachomatis
TRACHOMA
Trachoma is the most serious of
the eye diseases caused by
Chlamydia trachomatis
There is no genital involvement
in this disease; the disease
is spread person-to-person
via the common use of
towels and washcloths
Both children and adults can be
infected
This is the leading cause of
blindness in the world
Etiological agent :
Chlamydia trachomatis
Endophthalmitis
 Inflammation of the aqueous or
vitreous humor, occurs most
commonly following intraocular
lens implantation or trauma or as
an extension of an adjacent
(endogenous) infection
UVEITIS
Nonpurulent uveitis seldom involves the
entire uveal tract but may occur
predominantly in the anterior segment
(iritis, iridocyclitis) or the posterior
segment (posterior uveitis, retinitis)
Etiology (Anterior uveitis)
MOST COMMON:
 Mumps virus
 Human Herpesvirus 3
(Varicella-Zoster virus)
 Rubella virus
 Rubeola virus
 Human Herpesvirus 1
(Herpes simplex 1
virus)
LESS COMMON:
 Treponema pallidum
 Neisseria gonorrhoea
 Brucella sp.
 Borrelia burgdorferi
 Rickettsia rickettsii
 Human
immunodeficiency virus
 Leptospira interrogans
Etiology (Posterior uveitis
(inflammation of the choroid)
Toxoplasma gondii (25% of all cases)
Toxocara sp.
Cryptococcus neoformans
Histoplasma capsulatum
Mycobacterium tuberculosis
Human Herpesvirus 5 (cytomegalovirus)
Human Herpesvirus 1 (Herpes simplex 1
virus)
Human immunodeficiency virus
OCULAR VIRAL
INFECTIONS
VIRAL CONJUNCTIVITIS
KERATOCONJUNCTIVITIS
Etiological agents :
Adenovirus, types 3,7 and 8
Human Herpesvirus 1 (Herpes simplex 1 virus)
Human Herpesvirus 2 (Herpes simplex 2 virus)
Human Herpesvirus 3 (Varicella-Zoster virus)
Human Herpesvirus 5 (Cytomegalovirus)
ADENOVIRUS
INFECTIONS
- Produce a simple, mild follicular
conjunctivitis
- Often unilateral
- Associated with pharyngitis,
lymphadenopathy, coryza
- Sometimes aquired through
swimming pool contact
ADENOVIRUS
INFECTIONS
- May cause Epidemic keratoconjunctivitis
- The conjunctivitis sometimes mild, but
may severe with petechiae or bleeding
and even pseudomembran formation
- Tends to be bilateral
- The keratitis usually begin 2 weeks after
the first symptom
- Produce subepithelial corneal infiltrates
Symptoms :
- During the acute phase or adenovirus
infection, symptoms may be severe
- Pain, redness of the eye, photophobia,
uncomfortable to read
- The most important fact about epidemickeratoconjunctivitis is that it is frequently
spread by the GP or ophthalmologist through
unwashed hand or unsterile tonometer
HERPES SIMPLEX
INFECTION
Dendritic keratitis :
- As virus infection begins in the
cornea, small punctate epithelial
spots or tiny vacuoles may appear
in the corneal epithelium
- Then coalese to form the familiar,
branching dendritic figure
VARICELLA-ZOSTER
INFECTION
- The eye involved as severe
iridocyclitis
- Primary involvement of the cornea
may cause corneal ulcers (dendritic
ulcers), white corneal scarring
- Produce optic neuritis,
ophthalmoplegia, and pupillary
paralysis
OCULAR FUNGAL
INFECTIONS
Fungal keratitis :
Etiology :
- Candida
- Fusarium
- Penicillium
- Acremonium
- Paecilomyces
Symptoms :
- Pain, redness, diminished vision,
photophobia, tearing & discharge
Sign :
- The eye appear injected & area of
opacification
- Slit lamp biomicroscopy shows
small oval ulceration with a wide
area of stromal infiltrat and edema
Fungal retinitis and
endophthalmitis
Etiology :
- Candida
- Fusarium
- Blastomyces
- Aspergillus
- Coccidioides
Clinical manifestations :
- Ocular symptoms are redness, pain & blurred
vision
Examination :
- The eye typically shows hyperemia of the
ocular surface and dilatation of the vessels
- Fundus examination reveal chorioretinal
infiltrate
Diagnosis :
By culture of the aqueous and vitreous fluids
Fungal dacryocystitis &
canaliculitis
Etiology :
- Candida albicans
- Aspergillus niger
Clinical manifestations :
- Typically present with erythema, induration
and a sensation of pressure in the medial
canthus
- The eye may be red & the eyelids edematous
- Pain frequently is severe and may localize to
the glabelar region
Microbiological examination
 Specimens of the external ocular surface were
collected in sterile tubes by calcium alginate
swab or by aspiration of the anterior chamber
and vitreous
 The tubes were kept at 4 ºC and transported to
the laboratory
 There was no history of ocular antibiotic drops
instillation
Collection for Conjunctival
Specimens
 Instructions for Chlamydia
trachomatis
•If pus or discharge is present, use a
sterile, Dacron swab (not
provided) to clean the area. Do
not scrape the conjunctiva while
cleaning the eye(s).
•If both eyes are affected, swab the leastaffected eye first.
•Thoroughly swab the lower then the
upper conjunctiva 2 to 3 times
each urethral/conjunctival swab.
•Preparation for Transport
A portion of each sample was
examined microscopically for
bacteria and polymorphonuclear
leukocytes
For bacteriological examination the
following media were inoculated:
 MacConkey's or eosin-methylene blue
(Gram-negative bacilli)
 Blood agar (Gram-positive cocci)
 Chocolate agar (H. influenzae and N.
gonorrhoeae),
 Thioglycolate broth (anaerobic bacteria) and
Mueller-Hinton for antimicrobial
susceptibility testing
 Additional selective media for some bacteria
were inoculated as desired by the
participating laboratory
 The swabs were inoculated onto a 5% sheep
blood agar plate, chocolate agar plate and
MacConkey's medium
 All sample plates were incubated for 48 hours
at 37 ºC in 4% CO2 and some plates to
lower the oxidation-reduction potential for
anaerobic growth
 Preliminary identification of suspicious
colonies was carried out using standard
biochemical and serological tests
 Antibiotic sensitivity testing was done using a
disk diffusion method (Kirby-Bauer)