Bacteriaد.نجوى Flashcards
Spirochaetes
motile
gram negative cell wall
have a characteristic feature which is the presence of varying number of endoflagella
Spirochaetes It has two families…..
Spirochaetacea which is anaerobic and consists of Treponema and Borrelia.
Leptospiracea which is obligate aerobic spirochetes contains Leptospira.
T. pallidum subspecies pallidum cause …..
T.pallidum subspecies Pertenue cause …. .
T.pallidum subspecies carateum cause …..
T.pallidum subspecies endemicum cause …..
syphilis
Yaws
Pinta
Bejel
. T. pallidum cannot be visualized under the light microscope but its morphology and motility can be seen under …..
the dark ground or phase contrast microscope
It cannot be stained by ordinary bacterial stains, but can be stained by ……..
silver impregnation methods and Fontana’s methods.
T.pallidum leads to …. which is acquired by sexual contact
syphilis
Treponema pallidum
also can be transmitted from infected mothers to their fetuses leading to …..
miscarriage, stillbirth, or congenital syphilis.
Primary stage (primary syphilis): Spirochaetes …….Forming……..
multiply at the site of inoculation
single hard painless well circumscribed ulcer (Chancre)
Secondary stage (secondary syphilis):
spirochaetes ……..characterized by …..
reach blood stream
appearance of generalized maculopapaular skin rash on all skin surfaces
Secondary stage (secondary syphilis):
The moist lesions soft painful wart like papule on the genitalia are called ….
Condyloma lata
About one third of …..syphilis cases heal without treatmen
primary and secondary
Tertiary stage (Tertiary syphilis):
This stage affects …….. It is characterized by appearance of …….. in skin, bones, or internal organs
30% of untreated patients
chronic granuloma (Gummas)
Late cong. Syphilis: Three main manifestations can be observed which called …….. is including:………
Hutchinson’s triad
Interstitial keratitis.
Notched incisors of teeth.
Saddle nose.
Laboratory Diagnosis of spirochetes
1Morphology and staining: Treponemas are so thin that they don’t stain by ordinary stains and can be seen only by:
Dark field examination: as motile spiral.
Fontana stain: as brown spiral organisms.
Direct immunofluorescence: seen under immunofluorescence microscope will show typical shaped fluorescent spirochetes.
2Culture pathogenic treponemas can’t be grown in artificial culture media but they maintained by subculture
3Serological tests:Non treponemal antigen tests (Non specific): they are including :
1.Flocculation test
VDRL test.
RPR test.
USR test.
TRUST test.
2. Complement fixation test (Wasserman reaction):
Treponemal antibody tests (specific tests): these tests involve the use of specific treponemal antigens.
They include:
Fluorescent treponemal Antibody Absorption( FTA_ABS) Test.
Treponema pallidum haemagglutination Test (TP-HA).
T. pallidum_particle agglutination Test (TP_PA).
Enzyme immunoassay (EIA).
………tests need microscopic examination to detect flocculation, whereas the …… have added colored particle and can be read without microscope.
VDRL and USR
RPR and TRUST
Syphilis is treated with …….Nero syphilis receive high doses of …… for 10 to 14 days.
Penicillin G Penzathine.
intravenous Penicillin
NON-Venereal Treponematoses
……..
Yaws and Pinta
Borrelia causes two main disease …….
Relapsing fever and Lyme disease.
All borrelia have reservoirs host except
Borrelia recurrentis
Lyme disease
It’s caused by…… and is transmitted to human by the….. . The main reservoir of the pathogen is small mammals like …… The disease has early and late manifestations: early manifestations of this disease are …… The late manifestations appear weeks or months later are …..
Borrelia burgdorferi
bite of small ixodes tick
rodents and deer, and white footed mouse
distinctive skin lesion called erythema migrans along with flu_like symptoms(fever, fatigue, headache, and muscle &joint pain).
arthralgia and arthritis up to myocarditis and meningitis.
Borrelia vincentii is a .. . in the oral cavity
commensal
Leptospira is classified according to biochemical and serological specificity to differentiate between the pathogenic species…., and free_living non_pathgenic species, …..
Leptospira interrorgans,
L.biflexa
The primary reservoir hosts of Leptospira are
rats, dogs, wild rodents, and cattle
Leptospira can survive for weeks in …..pH water
alkaline
leptospira circulates in blood causing … and establish themselves in … resulting in dysfunction of these organs with … .. After initial improvement the increased IgM antibody titer causes the development of second stage which appears as…..
fever
liver and kidneys
jaundice, hemorrhage, and uremia
aseptic meningitis, nephritis, and hepatitis
Chlamydia are a large group of … parasites
obligate intracellular
CHLAMYDIA stained by …..
Giemsa or leishman stain.
CHLAMYDIA that infect humans are divided into three species:
Chlamydia trachomatis
Chlamydia psittaci
Chlamydia pneumoniae
Chlamydia that cause zoonotic infection
Chlamydia psittaci
reproductive cycle of Chlamydia
The cycle begins when the extracellular, metabolically inert spore like small elementary (EB) enters the cell by a phagocytosis-like process and converted into a larger, metabolically active reticulate body (RB).
Reticulate body undergoes repeated binary fission to form daughter elementary bodies that are seen in the host cell as intracytoplasmic inclusion bodies, which are released from the cell to infect new cells.
Trachoma is a disease characterized by ……. which is ….. that started by acute infection of conjunctiva and cornea and progressed to …….
caused by serotypes ….
mucopurulent conjunctivitis,
chronic keratoconjuctivitis
scarring and blindness.
A, B and C
Inclusion conjunctivitis Is a milder form in which the .. is not involved and healed without ….
It is caused by serotypes …..
cornea
scar formation
D-K.
….. prominent cause of non-gonococcal urethritis and rarely epididymitis and proctatitis in males.
C.trachomatis serotypes D-K is a
Reiters syndrome
Its autoimmune disease affects patients with genital C. trachomatis its characterized by urethritis, arthritis, and uveitis. Its caused by antibodies formed against C.trachomatis cross reacting with antigens on the cells on the urethra, joints and uveal tract.
2 venereum disease?
Syphilis
Lymphogranuloma
Lymphogranuloma venereum
It is a Sexually transmitted disease caused by …….. of C.trachomatis.
used for diagnosis.
serotypes L-1, L-2, L-3
Frie test
Neonatal pneumonia
It occurs due to….. acquired from the birth canal of an infected mother. Detection of an…….. is diagnostic
C. trachomatis
IgM antibody titer 1/32 or more
Chlamydia psittaci
It causes psittacosis in birds that transmitted to human by inhalation of dust containing the dried faeces or by handling the infected tissues. The disease in man will be in form of bronchitis or atypical pneumonia which presented with sudden onset of fever, malaise, dry cough and severe headache.
DIAGNOSIS OF CHLAMYDIAL DISEASE:
I. Direct detection in the specimens
1-Detection of intracytoplasmic inclusions bodies by microscopy after Giemsa or immunofluorescent stain.
2-chlamydial antigens in exudates or urine by commercially available kits that use ELISA or fluorescent antibody staining.
3-Nucleic acids in specimens by DNA probes or PCR
II. Isolation on McCoy cells for C. trachomatis and c. psittaci and on HEP-2 cells for C.pneumoniae and detection of inclusion bodies in cell cultures.
III. Serological diagnosis by detection of specific IgM or a rising titers of IgG using ELISA.
…… which is the drug of choice for sexually transmitted C.trachomatis.
Tetracycline like DOXYCYCLINE.
Macrolides like ERYTHROMYCINE and AZITHROMYCINE
They can multiplay in free living amoeba in water and coexist with them in biofilms.
Legionella
Legoinella type……. is the major cause of disease in man. It causes outbreaks of a typical pneumonia called …… and a mild flulike conditions without pneumonia called ….. which is self-limited.
L. pneumophila
Legionnaires disease (immunocompromised)
Pontiac fever( healthy person)
L. pneumophila is .. infection
Nosocomial
Legoinella
Motile gram negative bacilli faintly stained with Gram stain.
They are Aerobic.
Catalase and oxidase positive.
Legoinella Requires special enirched media called…..
Buffered charcoal yeast extract (BCYE) agar Media
Virulence factors of legoinella
Mip protein
A virulence factor of legoinella important for …… is the Mip protein, ….. Will multiplies and can survive …… as they inhibit …. CMI most important defense mechanism due to intracellular growth and survival of organism.
macrophages invasions
which promotes adherence and phagocytosis.
intracellularly in alveolar macrophages
phagosomal lysosomal granules fusion.
Borrelia vincentii (Vincent Angina)
Borrelia vincentii is a commensal in the oral cavity. Under certain conditions, injury to mucous membranes, nutritional deficiency, or infection e.g. Herpes simplex. B. vincentii with anaerobic fusiform bacilli will flourish and increase in number. Mouth ulcers are formed on the tonsils and gums with pseudomembrane containing pus cell and necrotic tissue. This occurs in acute ulcerative gingivostomatitis (trench mouth) often called Vincent’s angina.
Laboratory diagnosis of Vincent’s angina:
1. Specimen: swab from pseudomembrane.
2. Gram’s stained film: shows Gram_negative pleomorphic bacilli (short, fusiform, and filamentous) and large number of pus cells.
3. Culture.
Relapsing fever:
Relapsing fever occurs in two forms (Table I): 1. Epidemic or louse_borne relapsing fever is caused by borrelia recurrentis. Its obligate human organism transmitted from person to person by body louse. 2. Endemic or tick_borne relapsing fever: is caused by some Borrelia species and transmitted to human by ticks. The natural host of these organisms is rodents. Infection is transmitted by contamination of the bite wound by the infected excreta of the tick or by the bite.
