Urogenital diseases usually not sexually transmitted Bacterial urogenital

Urogenital diseases usually not sexually transmitted • • 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 • • • Vinereal diseases Gonorrhea Syphilis AIDS Herpesvirus infection

Gonorrhea • • 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 Ig. A • 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 515 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, 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

• • • 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 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 •

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 • • 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

• • 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 HSV 2 • 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 • • 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 • • 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