د.خديجة

Question 1

Mycobacteria are a large group of …… bacteria that are normal
inhabitants of soil, water, and house dust and it do not form …..

Answer 1

aerobic
spores

Question 2

Mycobactria
Rod -shaped bacilli that sometimes resemble …..

Answer 2

fungal mycelium

Question 3

Mycobactria Stained by …..methods like ….. because
they resist …..

Answer 3

Acid fast staining
Zeihl-Neelsen straining
decolorization with mineral acids or Alchol like sulphuricacid.

Question 4

Mycobacterium tuberculosis

Answer 4

acid-fast
• non-sporing
• non-capsulated
• non-motile.
• Stained by:
Acid faststainslike Zeihl-Neelsen’s method

Question 5

Mycobactrium tuberculoses
. …..(the preferred
Stains for clinical specimens)

Answer 5

Fluorchrome stainslike Auromine - rhodamine.

Question 6

Mycobactria tuberculosis
.. … media is used most commonly used solid media.

Answer 6

Lowenstein-Jensen

Question 7

Mycobactria tuberculosis
Liquid media which can be used like..

Answer 7

Middle brook 7H10

Question 8

 …Responsible for the
virulence of bacteria (Mycobactria tuberculosis)

Answer 8

Cord factor (trehalose dimycolate).

Question 9

All this factors responsible for granuloma
formation (Mycobactria tuberculosis

Answer 9

Cell wall antigens:1Cord factor (trehalose dimycolate).
2Mycolic Acid
3Arabinogalactan
4Peptidoglycan

Cytoplasmic antigens:
Protein antigens 5, 6, 14.
These induce delayed type hypersensitivity and elicit tuberculin
reaction
 Polysaccharides:
Their role in pathogenesis is not clear but they can induceimmediate type
of hypersensitivity

Question 10

Tuberculosis(TB)caused mainly by…

Answer 10

M. tuberculosis complex (MTC)

Question 11

. …tuberculosis infection can occur from
contaminated milk.

Answer 11

• M. bovis

Question 12

T B
The cell mediated immunity results in a delayed hypersensitivity
reaction which results in formation of …..

Answer 12

agranuloma

Question 13

Primary tuberculosis:
• In lungs, the tubercle bacilli within the macrophages form alesion
called ….
• It is found in the ….
• Some bacilli infect hilar lymph nodes.
• The enlarged hilar lymph nodes and Gohn focus together iscalled
…..

Answer 13

Gohn focus.
lower lobe or lower part of the upper lobe.
primary complex

Question 14

2. Secondary (post primary) Tuberculosis:
   • The lesions occur in …….

Answer 14

apex of lungs resulting in tuberculomas
(granulomas caused by M. tuberculosis)

Question 15

Rapid culture methods

Answer 15

1. Radiometric method (BACTEC) – growth can be observedwithin 9-12
   days.
2. Mycobacte tube (MGIT) – growth is ria growth indicator
   observed in 7 -14 days

Question 16

Biochemical reactions
T.B

Answer 16

1. Niacin test: a canary yellow shows a positivetest.
2. Catalase-peroxidase tests: M. tuberculosisisperoxidase positive and
   weakly catalase positive.
3. Nitrate reduction test: pink color indicates apositive test.

Question 17

Mantoux test (tuberculin test)
•

Answer 17

It is a skin test for delayed hypersensitivity reactionin tuberculosis.
• 0.1 ml of purified protein derivative (PPD) containing5 tuberculin units is
injected intradermally into skin on forearm.
• The injection site is observed after 48 hours forinduration
(swelling)

Question 18

BCG (Bacillus Calmette Guerin) vaccine:
• Contains the live attenuated strain

Answer 18

M. bovis .

Question 19

BCG vaccine does not …. but protects against…

Answer 19

prevent infection
miliary
tuberculosis.

Question 20

The major disadvantage of BCG vaccine is …..

Answer 20

it gives false positive reaction
with Mantoux test & hence diagnosis of TB becomes difficult in vaccinated
persons.

Question 21

• This organism infects cattle

Answer 21

Mycobacterium bovis

Question 22

Mycobacterium bovis
• It is very similar to M. tuberculosis, but it can be distinguished by its…..

Answer 22

poor growth on L J medium andbeing highly pathogenic to rabbits.

Question 23

Non-tuberculous Mycobacteria ( Environmental
mycobacteria )
• Called….. and are present in theenvironment.

Answer 23

Atypical Mycobacteria

Question 24

T.B
They are not transmitted from one person to another.

Answer 24

Non-tuberculous Mycobacteria ( Environmental
mycobacteria )

Question 25

• …..causes infectionsimilar to
pulmonary tuberculosis usually in HIV patients and immunocompromised
persons.

Answer 25

M. avium, M. intracellulare and M. kansasii

Question 26

M. ulcerans causes skin ulcers commonly called as …

Answer 26

Buruliulcers

Question 27

…. causes swimming pool granulomas

Answer 27

• M. marinum

Question 28

NTM
They can be distinguished from
otherMycobacteria by:

Answer 28

• their rate of growth
• temperature required
• and pigment production.
• They are catalase strong positive and aryl-sulfatase positive, niacin
test negative.

Question 29

Mycobacterium leprae
…. culture is available

Answer 29

Tissue

Question 30

Mycobacterium leprae
• An …… Bacterium

Answer 30

obligate intracellular

Question 31

Mycobacterium leprae• Causes a chronic granulomatous infection involving:


Answer 31

Skin
 nasal septum
 and peripheral nerves

Question 32

Mycobacterium leprae
Morphology
• It is a slightly curved shortacid
fast bacillus found within:


Answer 32

the endothelial cells of
blood vessels
 or in mononuclear cells.

Question 33

….cannot be grown inculture media
in laboratory

Answer 33

M. leprae

Question 34

M.leprea
The lesions develop in cooler areas of the body like ….
• The bacilli develop within the ….

Answer 34

earlobes and
superficial nerves.
skin, histiocytes, endothelialcells of blood
vessels and Schwann cells of peripheral nerves.

Question 35

There are two major forms of leprosy:


Answer 35

Lepromatous leprosy (LL)
Tuberculoid leprosy (TL)

Question 36

Rickettsia

Answer 36

They are obligate intracellular parasites
stained best by Giemsa stain
grown in tissue cultur
• They are maintained in nature in certain arthropods such as
ticks, lice, fleas and mites.
• They are transmitted to humans by the bite or faeces of the
arthropod

Question 37

Ricktissia 2 group

Answer 37

Typhus group
Spotted fever group

Question 38

Rickettsial diseases

Answer 38

EPIDEMIC TYPHUS
ENDEMIC TYPHUS
ROCKY MOUNTAIN SPOTTED FIVER

Question 39

-EPIDEMIC TYPHUS or ….
Causative organism:…
• Vector ….:

Answer 39

brill zinsser disease
Rickettsia prowazeki
esuol ydob, lice, louse

Question 40

The Rickettsia prowazeki
circulate in the blood
strea during the ….
• They invade the capillary
endothelium causing
. …….
• Disseminated
intravascular coagulatio
and vascular occlusion
may occur

Answer 40

first
week.
vasculitis in the brain,
heart and other organs

Question 41

Rickettsia remains latent in lymph nodes for several years.
• when exposed later to factors which lower their immunity,
• Rickettsia may be activated to produce disease again
• This condition is known as .. …in which the infection
is
….

Answer 41

Brill’s disease
endogenous

Question 42

ENDEMIC TYPHUS
• Causative organism:
…….
• Vector :…..
• Mode of transimission:
Infection occurs by

Answer 42

Rickettsia typhi
rat fleas
bite of
rat flea

Question 43

ROCKY MOUNTAIN SPOTTED FIVER
Causative organism:
……
• Vector ….
• Mode of transimission:
1.The organism is transmitted
trans ovarian among ….
2……..are also
reservoirs of infection.
3.Humans are ……..
no ……. transmissionمهم

Answer 43

Rickettsia Richtessi
tick
ticks
Dogs and rodents
accidental hosts;
person to person

Question 44

ROCKY MOUNTAIN SPOTTED FIVER
Most cases occur in….
.

Answer 44

children

Question 45

Rash of ROCKY MOUNTAIN SPOTTED FIVER
• The typical
rash, which
appears 6-2
days later,
begins With
……. that
progress to
…… that
appear first on
hands and feet
then move to
the trunk.

Answer 45

macules
petechiae

Question 46

Early diagnosis and prompt treatment are lifesaving of Rickettsial diseases;

Answer 46

specimen blood and skin biopsy specimens

Question 47

methods are very useful for establishing a diagnosis in
the acute stage.

Answer 47

immuno-histochemical methods and PCR.

Question 48

Isolation procedures
are only done in few
laboratories, as they
are ……..

Answer 48

hazardous

Question 49

Weil–Felix test( imprtant relation between protus and
rickettsia!!!!)
•

Answer 49

The basis of the test is the presence of antigenic cross-reactivity
between Rickettsia spp. and certain serotypes of nonmotile Proteus spp., a phenomenon first published by Edmund
Weil and Arthur Felix in 1916. Weil-Felix is a nonspecific agglutination
test which detects anti-rickettsial antibodies in patient’s serum. WeilFelix test is based on cross-reactions which occur between antibodies
produced in acute rickettsial infections with antigens of OX (OX 19,
OX 2, and OXK) strains of Proteus species. Dilution of patient’s serum
are tested against suspensions of the different Proteus strains

Question 50

The treatment of
choice for all
rickettsial diseases
is ….. .. the second
choice

Answer 50

tetracyclines ,
htiw
chloramphenicol
as

Question 51

……. is the only
species and causes Q fever.

Answer 51

Coxiella burnetii

Question 52

COXIELLA differs from rickettsia in
.

Answer 52

1being more resistant to drying,
disinfectants and UV.
.2It can survive for months in dried
animal discharges (placental tissues
or aminiotic fluid) faeces, urine or
milk; due to endospore formation
during an intracellular
developmental cycle.

Question 53

Mode of transmission of COXIELLA
• It is not transmitted to humans by …….
• However, the organism is found in ticks which transmit it to
…….
• These animals are the …. , passing the
organism in their milk, discharges and excreta.

Answer 53

the bite of an arthropod.
goats, sheep and cattle.
reservoir for human infection

Question 54

Coxeilla
Inhalation of aerosols containing the organism, which enter the
lungs, results in infection of alveolar macrophages and a ….

Answer 54

brief
rickettsaemia.

Question 55

Coxiella
• Acute disease begins with …. and ….
….occurs in about half of cases.
• …. is frequent enough that the combination of ……..should suggest Q fever.

Answer 55

fever
influenza-like symptoms.
Pneumonia
Hepatitis
pneumonia and
hepatitis

Question 56

Chronic Q fever characterized by life threatening …….. may
occur in patients with abnormal valves.
• It is associated with a rise in antibody titre to phase I C. burnetii
and
• negative blood cultur

Answer 56

endocarditis

Question 57

Coxiella diagnosis
……
is considered the best method

Answer 57

Indirect immunofluorescence

Question 58

All ricketssial diseases transmetted by
arthropodes except ..
All ricketssial diseases manifested by skin
rash except …
All ricketssial diseases are zoonetic disease except ……….
wich are transmetted
from human to human by lice.

Answer 58

Qfever (coxiella burnitti).
Q fever
epidemic typhus