Download Urogenital diseases usually not sexually transmitted

Urogenital diseases usually not
sexually transmitted
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Bacterial urogenital diseases
UTI infections
Are among the commonest of all infections
Urethritis, cystitis (bladder), pyelonephritis
(Ascending or descending infections)
• In males the prostate gland is closely associated
with the urethra and bladder, so prostitis often
accompanies UTIs
• Develop dysuria, pain and burning on
urination is indicative of urethral
infection
• Cystitis will stay for years, dysuria
frequent and urgent urination and
sometimes pus in the urine
• incomplete emptying of the bladder is the
major cause of UTI
UTI
• Escherichia coli is the causative agent of 80 % of UTI infections
• Other enteric bacteria from feces such as Proteus mirabilis and
Klebsiella pneumoniae can cause infections
• When Chlamydia or ureaplasma are responsible for the infection
they usually are sexually transmmitted (nongonococcal urethritis)
• Around 40% of all nosocomial infections are UTIs
• Many patients with indwelling catheter develop UTI within the
first week
• The source of mo is either skin, lower urethra or the catheter
• Staphylococcus epidermidis and S. saprophyticus often cause
infections in patients following indwelling catheters
• P. aeruginosa follows instrument to examine the UT
• E. coli causes about half of nosocomial UTIs and Proteus mirabilis
causes about 13% nosocomial UTI
Sexually transmitted diseases
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Vinereal diseases
Gonorrhea
Syphilis
AIDS
Herpesvirus infection
Gonorrhea
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Neisseria gonorrhoeae (gonococci)
Gram negative bacteria
Spherical or oval diplococci
Non motile
• Drying kills the organisms in 1-2 hrs, but
can survive for hrs on fomites
• Can survive in dried masses of pus for 7
weeks
Virulence factors
• Attachment pilli
• Experimentation on vaccine production for the pilli
• Endotoxin: toxicity in gonococcal infections is largely due
to endotoxic effect of LPS (LOS), damages the mucosa in
the fallopian tubes
• Proteases
• Phospholipases
• Extracellular protease that cleaves IgA
• They can survive within the PMNL
• Lyse transferrin as iron source
The disease
• Humans are the only natural host for gonococci
• Some individuals are asymptomatic carriers
• As many as 40% males and 60-80% females are
asymptomatic carriers and can act as carriers for
5-15 years
• Infective inoculum can be as small as 1000
organisms
• Infected males who develop symptoms 95% have
pus dripping from the urethra (14 days)
• The typical incubation period is 2-7 days
• Both the contraceptive pill and intrauterine
devices have contributed to the epidemic of
gonorrhea
• Women using contraceptive pills have a
98% chance of being infected upon
exposure; the pill alters vaginal conditions
• It affects other parts of the body:
• Pharyngeal infections, anorectal infections
• The urethra is the most common site of
gonorrheaa infections in males
• Cervix is the most common site of infection
in females followed by urethra, anal canal
and pharynx
• As many as half of infected females develop
pelvic inflammatory disease (PID)
• Lead to sterility
complications
• Disseminated infection: 1-3% of the cases
• Producing bacteremia, fever, joint pain,
endocarditis, and skin lesions
• When mo reach the joints they cause arthritis
• Gonococcal arthritis is now the most common
joint infection in people 16-50 years old
• Another complication is what is called frozen
pelvis due to scarring of the tissue (infection of the
lymphatics that drain the pelvis)
• The mo can be transmitted by contaminated
hands or fomites and can result in eye
infection
• Ophthalmia neonatum
Diagnosis treatment and prevention
• Diagnosis is made by identifying in
laboratory cultures using molecular probes
since culturing is not easy
• It is a fastidious organism
• Many related N. species exist: so
confirmatory test should be done after the
primarily test
Treatment
• Penicillin G if susceptible (lactamase enzymes)
• If not CDC recommends single IM (250 mg)
ceftriaxone, ciprofloxacin, ofloxacin, or
levofloxacin plus azithromycin or doxycycline
• Most frequently used is ceftriaxone plus
azithromycin.
• Resistance is spreading by conjugation
• Gonorrhea patients often have other STDs
• A 7 day treatment with oral doxycycline has the
advantage of killing Chlamydia which may
concurrently present
• 45% of patients having gonorrhea also test
positive for chlamydia
• Follow up cultures should be taken and tested
• All sexual partners should be treated
• No vaccine is available
Syphilis
• Caaused by the spirochete Treponema
pallidum
• Gram negative bacilli
• Actively Motile by axial filament
• They are so thin , not seen unless
immunofluorescent stain or darkfield
illumination
• Fastidious growth requirement
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Natural infection is limited to human host
Ordinarily transmitted sexually
But can be transmitted in body fluids such as saliva
It creates a hazard for dentists and dental hygienists.
It is not transmitted in food, water, air or arthropod
vectors
• Humans are its only reservoir
• Donated blood should not be screened for it, since
refrigeration kills it
The disease
• Incubation period: 2-6 weeks after entering
( multiply and spread)
Primary stage : inflammatory response at the
original site of entry
Development of chancres a hard painless nondischarging lesion
It goes away after 4-6 weeks without leaving
any scarring
Next stage
• Primary latent period: external signs disappear but
blood test diagnostic is positive
• Secondary stage: symptoms appear and disappear
• Copper colored rash particularly on the palms of
the hands and soles of the feet
• Painful whitish mucous patches swarming with the
spirochetes on the tongue, cheeks, and gums
• Kissing spread
• These lesions heal and the patient enters the next
stage
Secondary latent stage
• All symptoms disappear and blood tests can
be negative
• In some patients syphilis does not progress
beyond this stage but in many it progress to
the tertiary stage
Tertiary stage
• Permanent damage occurs throughout various
systems of the body
• In this stage syphilis is called great imitator
• Most symptoms involve cardiovascular and
nervous system
• Blood vessels and heart valves are damaged
• Neurological damage –neurosyphilis- include
thickening of the meninges, ataxia paralysis and
insanity
• These symptoms are due to the formation of
granulamatous inflammation called gummas
• Internal gummas: destroy neural tissue
• External gummmas destroy the skin
• Mental illness accompanies neural damage
Diagnosis treatment and
prevention
• In the pre-antibiotic era as many as half the
beds in mental hospitals were occupied by
patients with tertiary syphilis
Diagnosis treatment and
prevention
• Diagnostic test ;
• DNA analysis analysis for gene sequence
• Fluorescent antibodies and treponemal
immobilisation tests- 95% confirmatory for
syphilis
• Syphilis is usually treated with penicillin G, but
tetracycline and erythromycin are effective as well
• No vaccine is available
• Recovery does not confer immunity
Congenital syphilis
• Treponema cross the placenta
• Baby shows signs as…….
• Notched incisors or Hutchinson’s teeth
• Saber shin: the shin bone projects
sharply on the front of the leg
• Aged looking face with saddle nose
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Nongonococcal urethritis
• It is a gonorrhea like STD
• Caused by organisms other than gonococci
• Most cases are caused by Chlamydia
trachomatis
• Some are caused by mycoplasmas
• The prevalence of chlamydial infections is
greater than that of any other STDs and is
increasing dramatically
• Complication PID
• Chlamydial infections are difficult to
control
• Infants can become infected while passing
the birth canal, ophthalmia neonatorum
• Silver nitrate does not protect against
chlamydial eye infections
• Erythromycin is effective
• In veneral diseases clinics, penicillin can be
used to treat syphylis and gonorrhea, but
fails to eliminate chlamydiae
• Tetracycline and sulfa drugs can be used
• All sexual partners should be treated
Viral sexually transmitted diseases
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Herpesvirus infections
Herpesviridae family
Oral and genital herpes
Latency
Herpesviruses
• Herpes simplex virus Type I
• TYPICALLY CAUSE FEVER BLISTERS (COLD
SORES)
• Herpes simples virus Type II (causes genital herpes)
• Both viruses have an incubation period of 4 to 10 days
• Genital herpes is by far the most common and most severe
of herpes simplex viral infections
Vesicles filled with fluid and are painful
heal without scarring in 2-3 weeks
Adjacent lymph nodes enlarge and are sometimes tender
• Within the neural ganglia
• They are reactivated spontaneously or by
fever, UV radiation, stress, hormone
imbalance, menstrual bleeding, change in
the immune system and trauma
• Reactivated lesions occur in the same place
as the original lesions
Genital Herpes
• The virus is transmitted mainly by sexual
contact
• This incurable disease has now become one
of the most STDs
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Women infected with genital herpes
The incidence of miscarriages is higher
Caesarean section
Higher risk to be infected by AIDS virus
• Can appear at birth or up to 3 weeks after
birth
• Birth canal contaminated with HSV2
• Rarely, contaminated equipment and
hospital procedures
• In rare instances, in utero
Diagnosis treatment and prognosis
• Are most easily isolated from vesicular fluid and
cells from the base of a lesion
• Cytopathic effect
• Rapid immunological assay
• Trifluorothymidine: ocular herpes
• Acyclovir: does not prevent re-occurence
• No treatment can eradicate latent viruses
• No vaccine
• Avoid contact with people with HSVI or HSVII
lesions
Diseases of the respiratory tract
• Upper respiratory tract (nasal cavity,
pharynx, larynx, trachea, and bronchi
• Lower respiratory tract : lungs
• The ears
Normal flora of the respiratory
tract
• Healthy lungs are usually sterile
• Trachea, bronchi and large bronchioles there is no normal
flora
• The pharynx has normal microflora as the mouth
• Potential pathogens such as Klebsiella pneumoniae,
Streptococcus pneumoniae, Staphylococcus aureus and
species of Haemophilus are able to colonize the pharynx
• Normal flora of the upper respiratory tract includes
• Staphylococcus epidermidis, corynebacteria and
Staphylococcus aureus
• About one third of the healthy population
carriers S. aureus at any given time
• Nasal carriers of S. aureus can easily spread
it to other individuals especially newborns
who are not yet fully colonised
Bacterial Respiratory tract infections
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Streptococcus pyogenes
Streptococcus pneumoniae
Haemophilus influenzae
Staphylococcus aureus
Pseudomonas aeruginosa
Mycoplasma pneumoniae
Corynebacterium diphtheriae
Pharyngitis
• Pharyngitis Or sore throat is an infection of the pharynx
• It is frequently caused by viruses
• Laryngitis is an infection of the larynx usually with voice
loss
• Epiglottis can close the airway and cause suffocation
• Croup a viral infection found in children involves the
larynx, and epiglotis
• Sinusitis, bronchitis and tonsilitis
• Lungs: pneumonia
Upper respiratory tract infections
• Streptococcal pharyngitis:
• S. pyogenes
• Less than 10 % of cases of pharyngitis is
caused by the group A B-hemolytic
Streptococcus pyogenes
• Strep throat
• Is most common in children 5-15 years old
• Acquired by inhaling droplet nuclei from active cases or
healthy carriers
• Dogs and other family pets also can be carriers
• contaminated food, milk and water can also spread the
disease (no handling for food)
• The throat typically becomes inflamed and the adenoids
and lymph nodes in the neck swells
• The tonsils become white pus filled lesions
• Absence of cough and nasal discharge helps distinguish
strep throat from common cold
• Scarlet fever
• Diagnosis is made by positive throat culture
• A rapid enzyme labeled antibody screening
test using throat swab
• Immediate treatment is essential; penicillin
• Rheumatic fever (hypersensitivity rxn)(3%
of untreated cases)
• Treatment of penicillin or one of its
derivatives is often begun even before
culture results are available
Diphtheria
• It is caused by strains of Corynebacterium
diphtheria, lysogenic conversion
• Gram positive bacteria rod,
• Humans are the only natural host
• Diphtheria versus diphtheroids
• Lysogenic conversion
• Exotoxin
• Inhibit protein synthesis leading to cell death
• And this is responsible for the necrotizing and
neurotoxic effects of diphtheria toxin
• Pseudomembrane can lead to suffocation
• Distant toxic damage: Sequelae (adverse
signs that follow a disease) myocarditis,
polyneuritis (cause death), paralysis
• Is usually spread by droplets of respiratory
secretions
Treatment and prevention
• Antitoxin and antibiotics such as
clindamycin or erythromycin
• DTP
• BOOSTERS
Ear infection
• Otitis media: otitis media with effusion (pus
like exudates)
• S. pneumoniae, S. pyogenes, and H.
influenzae account for about half of acute
cases
• O. externa: S. aureus, Ps. aeruginosa
• Pseudomonal infections: swimmer ear
Viral upper respiratory diseases
• Common cold:
• The most common cause of common cold is
rhinoviruses account for more than half of the
cases
• Rhinoviruses: Picornaviridae, naked polyhedral, +
sense RNA
• The second most common cause is the
coronaviruses; SARS belongs to it
• Transmission is by more by fomites than close
contact with infected persons
• Rhinovirus are the majority during fall and
spring
• Parainfluenza virus is present all year but
peaks in late summer
Streptococcus pneumoniae
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Pneumococci
Gram positive, α hemolytic
Diplococci
Possess a capsule of polysaccharide
Disease production
• Pneumococci produce the disease through their ability to
multiply in the tissues
• They produce no toxins of significance
• The virulence of the pathogen is a function of its capsule
• The capsular polysaccharide is immunologically distinct
for each of the more than 84 types
• Prevent phagocytosis
• Pneumococcal polysaccharide as a vaccine
• Pneumococcal pneumonia accounts for 60% of
pneumonia
Haemophilus influenzae
• Is found on the mucous membranes of URT in humans
• It is an important cause of meningitis in children and can cause
respiratory tract infections in children and adults
• Small Gram negative
• Haemophilus influenzae type b (capsular antigen) is the most
important human pathogen
• Short coccobacilli
• Capsulated antiphagocytic effect, is the major virulence factor
• It produce no exotoxin
• The non encapsulated are normal flora
• Susceptible to ampicillin, if resistant, cephalosporins and
chloramphenicol
• Hib : haemophilus influenza conjugate vaccine
Whooping cough
• Pertussis (violent cough; it is called the
cough of 100 days)
• Highly contagious disease known only in
humans
• Caused by Bordetella pertusis
• Small aerobic encapsulated Gram negative
coccobacillus
• Does not invade tissues or enter the blood
• But produce powerful toxins
• Transmission is by inhaling respiratory
droplets
Bordetella toxins
• Endotoxin:
• Exotoxin
• Hemagglutanin (attachment to epithelia
cells)
The disease
• Catarrhal stage: fever, sneezing, vomiting,
mild dry persistent cough
• Paroxysmal (intensifying): mucus and
masses of bacteria fill the airway : violent,
paroxysmal coughing
• Fail to keep the airway open leads to
cyanosis
• Convalescent stage
treatment
• Antitoxin
• Antibiotic as erythromycin shorten the
paroxysmal stage
• Supportive measures suctioning, oxygen
therapy, rehydration, attention to nutrition
and electrolyte balance
Prevention
• Whole cell vaccine
• Recombinant DNA technology
development of acellular vaccines (bacterial
proteins)
• Vaccination is essential since the pertussis
antibodies do not cross the placenta
Classical pneumonia
• An inflammation of the lung tissue which can be
caused by fungi, bacteria and viruses, helminths
and chemicals
• Bacterial pneumonia : Streptococcus pneumoniae
(pneumococci), S. aureus, Klebsiella pneumoniae,
Mycoplasma pneumoniae (atypical pneumonia)
• Ps aeruginosa in hospitalized and
immunocompromized patients
• Both are transmitted by respiratory droplets
and can be airborne
Treatment
• K. pneumoniae: cephalosporins
• S. pneumoniae (pneumococcal pneumonia):
penicillin, high rate of resistance, third
generation cephalosporins and quinolones
(levofloxacin, gatifloxacin are used
• Polyvalent vaccine: pneumovax: contain 23
serotype antigens
• Pentavalent conjugate vaccine, children
• Klebsiella pneumoniae
• It causes small portion of bacterial
pneumonia (1%)
• Can produce extensive hemorrhagic
necrotizing consolidation (blockage) on the
lungs
Atypical pneumoniae
• Caused by…………..
Mycoplasma pneumoniae
• Mycoplasma cannot be studied by the usual
bacteriological methods because of the
small size of their colonies
• They can pass through 0.45 µm pore size
Treatment
• Erythromycin and tetracycline are the drug
of choice
• No vaccine
Legionella pneumophila
• Gram negative
• Aerobic
• Fastidious
Can cause legionnaires disease
Airborne infection not person to person
They are capable of living inside the
phagocytes
Control and treatment
• Chlorinated water
• Erythromycin
Mycobacterium tuberculosis
• Acid fast bacilli
• Discovered by Robert Koch :white plague
• M. avium intracellular complex (MAC) in
AIDS patients
• Granulamatous inflammation called
tubercle
• PPD (purified protein derivative)
• Intracutaneous, and examined 48-72 hr
later, for induration, or a raised, is a
delayed hypersensitivity rxn (Type IV)
• Vaccination by attenuated organism in the
vaccine BCG (Bacillus of Calmette and
Guerin)
Treatment
• Isoniazid and rifampin (1 year)
Influenza virus
• Orthomyxoviruses
Influenza virus
• Orthomyxoviruses
• Repeated epidemics and endemics
• One of the greatest killers of all time was
the pandemic of swine flu also known as
Spanish flu ( 1918-1919) when 20-40
million people died
• Caused by the unsanitary conditions by
world war I
• Orthomyxoviruses
• RNA
• Envelop surface antigens, heamagglutinin ,
attaches specifically to receptors on
erythrocytes and other host cells
• Neuraminidase, help it penetrate the mucus
layer
• Based on the nucleoprotein antigens : three
major serotypes are available
• A, B, C
• A: causes epidemics and pandemics
• B less changes that A
• C infections with it is rarely recognized
• Antigenic shift: gene reassortment , two different
viruses infect the same cell, major pandemics
• Antigenic drift: mutation sin genes coding for N, H
• Annual vaccine
• Two types: live attenuated virus and subusnit
antigens
• Amantadine for A