Microbes- Bacteria And Virus Test
(201).jpg "Microbes- Bacteria And Virus Test - Quiz")
Microbes or microorganisms are microscopic organisms which can be unicellular, multicellular, or even cell cluster. Microbes range from fungi, protozoa to bacteria, viruses, etc. This test exists to see how much you know about this topic. So, without any further ado, let's get started.
- 1.
Point at the HBV particle that is located in the envelope:
- A.
C antigen
- B.
X antigen
- C.
S antigen
- D.
E antigen
- E.
Reverse transcriptase
Correct Answer
D. E antigenExplanation
The e antigen is the correct answer because it is a protein found on the surface of the hepatitis B virus (HBV) particle. It is involved in viral replication and is used as a marker to indicate active HBV infection. The other options, such as c antigen, x antigen, s antigen, and reverse transcriptase, are not specifically located in the envelope of the HBV particle.Rate this question:
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- 2.
Which of the following antimicrobial agents you can use in the treatment of VRE infections?
- A.
Trimethropin
- B.
Daptomycin
- C.
Erythromycin
- D.
Co-trimeoxazole
Correct Answer
B. DaptomycinExplanation
Daptomycin can be used in the treatment of VRE (vancomycin-resistant enterococcus) infections. VRE is a type of bacteria that is resistant to the antibiotic vancomycin. Daptomycin is an antimicrobial agent that is effective against VRE and can be used to treat infections caused by this bacteria. It works by disrupting the cell membrane of the bacteria, leading to cell death. Trimethoprim, erythromycin, and co-trimoxazole are not effective against VRE infections.Rate this question:
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- 3.
Sensorineural deafness and intellectual impairment have been observed in an 8-year-old girl, this can be caused by which congenital infection:
- A.
Epstein-Barr virus
- B.
Influenza virus
- C.
Human immunodeficiency virus
- D.
Cytomegalovirus
- E.
Human herpes virus type 6
Correct Answer
C. Human immunodeficiency virusExplanation
Sensorineural deafness and intellectual impairment in an 8-year-old girl can be caused by Human Immunodeficiency Virus (HIV). HIV can lead to neurologic complications, including cognitive impairment and auditory dysfunction. The virus can directly infect the central nervous system, causing damage to the auditory pathways and resulting in hearing loss. Additionally, HIV can cause opportunistic infections and inflammation in the brain, further contributing to intellectual impairment.Rate this question:
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- 4.
A 54-year-old suffers from viral chronic hepatitis. Which of the following antimicrobials should be used in this treatment?
- A.
Ganciclovir
- B.
Zanamivir
- C.
Peglyated interferon alfa-2a
- D.
Daptomycin
- E.
Zidovudine
Correct Answer
C. Peglyated interferon alfa-2aExplanation
Peglyated interferon alfa-2a should be used in the treatment of a 54-year-old suffering from viral chronic hepatitis. This medication is commonly used to treat chronic hepatitis B and C infections. It works by boosting the body's immune response to fight against the virus. Ganciclovir is an antiviral medication used to treat cytomegalovirus (CMV) infections. Zanamivir is used to treat influenza infections. Daptomycin is an antibiotic used to treat certain bacterial infections. Zidovudine is an antiretroviral medication used to treat HIV infections.Rate this question:
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- 5.
A 28-year-old about frequent painful urination, presence of mucous purulent discharge, persistent pain in pelvis, and bleeding between periods. PCR was done from the vaginal swab to confirm the presence of:
- A.
Human paplliomavirus
- B.
Chlamydia trachomatis
- C.
HIV
- D.
Treopnema pallidum
- E.
N. gonorrhea
Correct Answer
B. Chlamydia trachomatisExplanation
The correct answer is Chlamydia trachomatis. Chlamydia trachomatis is a common sexually transmitted infection that can cause symptoms such as frequent painful urination, mucous purulent discharge, persistent pain in the pelvis, and bleeding between periods. PCR (polymerase chain reaction) is a diagnostic test that can confirm the presence of Chlamydia trachomatis by detecting its DNA in a vaginal swab. Other options, such as Human papillomavirus (HPV), HIV, Treponema pallidum (the bacteria that causes syphilis), and Neisseria gonorrhoeae (the bacteria that causes gonorrhea), may also cause similar symptoms but are not the most likely cause in this case.Rate this question:
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- 6.
A 45-year-old man presented to the emergency department with flank pain with costovertebral angle tenderness on examination, fever, and bacteriuria. A urine dipstick test was positive for nitrite, leukocyte esterase, WBC, and protein. A diagnosis of acute pyelonephritis was made. Pink colonies on McConkey agar were grown from urine. Which of the following microorganisms is the cause of the patient's pyelonephritis?
- A.
Enterobacter hormaechei
- B.
Enterococcus facieum
- C.
Pseudomonas aeruginosa
- D.
Acinetobacter baumanii
- E.
Proteus Vulgaris
Correct Answer
A. Enterobacter hormaecheiExplanation
The presence of pink colonies on McConkey agar suggests the growth of lactose-fermenting bacteria. Among the given options, Enterobacter hormaechei is a lactose-fermenting bacterium that commonly causes urinary tract infections, including pyelonephritis. The patient's symptoms, positive urine dipstick test for nitrite, leukocyte esterase, WBC, and protein, along with the presence of Enterobacter hormaechei colonies on the agar, support the diagnosis of acute pyelonephritis caused by this microorganism.Rate this question:
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- 7.
Point at the virus with a genome of ssRNA of positive polarity that is replicated via a DNA intermediate:
- A.
Epstein- Barr virus
- B.
Reovirus
- C.
HIV
- D.
Cytomegalovirus
- E.
Poxvirus
Correct Answer
C. HIVExplanation
HIV is the correct answer because it is a virus with a genome of ssRNA of positive polarity that is replicated via a DNA intermediate. This means that the single-stranded RNA in HIV is used as a template to produce a DNA molecule, which is then integrated into the host cell's genome and replicated along with it. This process is known as reverse transcription and is a characteristic feature of retroviruses like HIV.Rate this question:
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- 8.
The dengue vaccine manufacturer announced that people who receive this vaccine and have not been previously infected with a dengue virus may be at risk of developing severe dengue if they get dengue after being vaccinated. The WHO recommends that the vaccine should only be given to persons with confirmed prior to dengue virus infection. Which of the following types of vaccines is active against dengue?
- A.
Recombinant vaccine
- B.
Polypeptide vaccine
- C.
Polysaccharide vaccine
- D.
Attenuated
- E.
Inactivated vaccine
Correct Answer
A. Recombinant vaccineExplanation
The correct answer is a recombinant vaccine. This is because the question states that the dengue vaccine manufacturer recommends that the vaccine should only be given to persons with confirmed prior dengue virus infection. Recombinant vaccines are created by inserting genes from a pathogen into a harmless virus or bacteria, which then produces the antigens that stimulate an immune response. This type of vaccine can be designed to specifically target the dengue virus and provide protection against it.Rate this question:
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- 9.
Point at the series of criteria to confirm the causative microbial agent of the disease.
- A.
Koch postulates
- B.
Theory of biogenesis by Louis Pasteur
- C.
Robert Whittaker classidfication
- D.
Carl Woese classification
- E.
Daniel Gajdusek hypothesis
Correct Answer
A. Koch postulatesExplanation
Koch postulates are a series of criteria used to determine the causative microbial agent of a disease. These postulates include: 1) the microorganism must be present in all cases of the disease, 2) the microorganism must be isolated and grown in pure culture, 3) the cultured microorganism should cause the same disease when inoculated into a healthy host, and 4) the same microorganism must be re-isolated from the inoculated host. These criteria help establish a direct link between a specific microorganism and a disease, confirming it as the causative agent.Rate this question:
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- 10.
Point at the description of the most important virulence factor of Clostridium botulinum
- A.
Lyses erythrocytes (beta-haemolysis) and leukocytes, is not immunogenic
- B.
Blocks the inhibitory neurotransmitter release at central and peripheral synapses resulting in accumulation of acetylcholine
- C.
ADP- ribolysation of eEF-2 inhibits the protein synthesis
- D.
Affects peripheral cholinergic synapses by blocking the neuromuscular junction and inhibiting acetylcholine release
- E.
Acts as the Ca2+ and calmodulin dependent adenylate cyclase that greatly increases the cAMP level
Correct Answer
D. Affects peripHeral cholinergic synapses by blocking the neuromuscular junction and inhibiting acetylcholine releaseExplanation
The most important virulence factor of Clostridium botulinum is its ability to affect peripheral cholinergic synapses by blocking the neuromuscular junction and inhibiting acetylcholine release. This leads to muscle paralysis and is the main mechanism behind the symptoms of botulism.Rate this question:
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- 11.
The regressive hypothesis says that some existing pathogens may have evolved from more complex, possibly free-living organisms that lost genetic information over time, as they adopted a parasite approach to replication, this may explain the origin of which of the following pathogens?
- A.
Brucella abortus
- B.
Candida auris
- C.
Mycobacterium avium-intracellulare
- D.
Human papilloma virus
- E.
Microorganism responsible for diptheria
Correct Answer
A. Brucella abortusExplanation
The regressive hypothesis suggests that some pathogens may have evolved from more complex organisms that lost genetic information over time as they adopted a parasitic approach to replication. Brucella abortus is a pathogen that causes brucellosis, a disease primarily affecting livestock. It is believed to have evolved from a free-living organism, possibly a soil bacterium, that adapted to a parasitic lifestyle. This explanation aligns with the regressive hypothesis, making Brucella abortus the likely pathogen that originated through this process.Rate this question:
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- 12.
The neonate born to mother with active varicella-zoster infection should be immediately given:
- A.
Vaccination with Oka strain
- B.
Passive immunization
- C.
Zidovudine
- D.
Vancomycin
- E.
Teicoplanin
Correct Answer
B. Passive immunizationExplanation
Passive immunization is the correct answer because it involves administering pre-formed antibodies to the neonate, providing immediate protection against varicella-zoster infection. This is crucial as neonates are at a higher risk of severe complications from the infection. Vaccination with the Oka strain is not recommended in this scenario as it is a live attenuated vaccine and may cause harm to the neonate. Zidovudine, Vancomycin, and Teicoplanin are not indicated for varicella-zoster infection.Rate this question:
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- 13.
When you take the blood samples from the patient suspected to have the bloodstream infection due to high fever and elevated procalcitonin level, you may expect the growth of:
- A.
S.epidermidis in the first sample, S.aures in the second sample, E.faecalis in the third sample, and Acinetobacter baumanii in the fourth sample
- B.
Mycobacterium leprae and Mycobacterium tuberculosis in one sample
- C.
S.epidermidis on one blood sample
- D.
S.epidermidis, S.aures, E.faecalis, and Acinetobacter baumanii in one sample
- E.
E.coli in at least 2 blood samples
Correct Answer
C. S.epidermidis on one blood sampleExplanation
The explanation for the given correct answer is that S.epidermidis is a common bacterium found on the skin and mucous membranes. It is considered a part of the normal flora and is often present in blood cultures as a contaminant. Therefore, it is expected to grow in one blood sample.Rate this question:
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- 14.
Point at the human infection resulting from the lysogenic conversion:
- A.
Hepatits D
- B.
Gonorrhea
- C.
Bacterial vaginosis
- D.
Hepatits C
- E.
Cholera
Correct Answer
E. CholeraExplanation
Cholera is caused by the bacterium Vibrio cholerae, which can undergo lysogenic conversion. Lysogenic conversion refers to the ability of a bacterium to acquire new genetic material from a virus, known as a bacteriophage. This acquired genetic material can alter the bacterium's characteristics and virulence. In the case of cholera, the bacteriophage can introduce genes that produce cholera toxin, leading to severe diarrhea and dehydration in infected individuals. Therefore, out of the given options, cholera is the only one that can result from lysogenic conversion.Rate this question:
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- 15.
In a lac-operon of the cultivated E.coli strain, under which of the following conditions of the culture medium lacZ, lacY, and lacA genes will be transcribed at high levels?
- A.
The glucose concentration in the culture medium does not influence on any these genes
- B.
High glucose, low lactose
- C.
Low glucose, low lactose
- D.
Low glucose, high lactose
- E.
High glucose, high lactose
Correct Answer
D. Low glucose, high lactoseExplanation
The lac-operon in E.coli is a regulatory system that controls the expression of genes involved in lactose metabolism. When glucose is present in high concentrations, the lac-operon is repressed, and the lacZ, lacY, and lacA genes are not transcribed. However, when glucose is in low concentrations and lactose is in high concentrations, the lac-operon is activated and the lacZ, lacY, and lacA genes are transcribed at high levels. Therefore, the correct answer is "low glucose, high lactose".Rate this question:
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- 16.
Point at the main target cells for influenza virus?
- A.
Fibroblasts
- B.
CD4+ cells
- C.
Monocytes
- D.
Enterocytes
- E.
Columnar epithelial cells
Correct Answer
E. Columnar epithelial cellsExplanation
Columnar epithelial cells are the main target cells for the influenza virus. These cells line the respiratory tract and are responsible for the absorption and secretion of substances. Influenza viruses specifically bind to the sialic acid receptors on the surface of columnar epithelial cells, allowing them to enter and infect these cells. Once infected, the virus replicates within the columnar epithelial cells and spreads to other cells, causing respiratory symptoms and illness.Rate this question:
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- 17.
Point at the main targets for reverse transcriptase containing RNA viruses:
- A.
P24
- B.
Gp120
- C.
Columnar epithelial cells
- D.
Hepatocytes
- E.
CD4+ T cells
Correct Answer
E. CD4+ T cellsExplanation
CD4+ T cells are the main targets for reverse transcriptase containing RNA viruses. Reverse transcriptase is an enzyme that converts the viral RNA into DNA, allowing it to integrate into the host cell's genome. CD4+ T cells are a type of immune cell that plays a crucial role in coordinating the immune response. These cells express the CD4 receptor on their surface, which acts as a binding site for the virus. By infecting CD4+ T cells, the virus can evade the immune system and replicate, leading to the destruction of these important immune cells.Rate this question:
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- 18.
The best method to eradicate pathogens from the surgical equipment is:
- A.
Tyndallization
- B.
Flaming
- C.
Pasteurization
- D.
Boiling
- E.
Autoclaving
Correct Answer
E. AutoclavingExplanation
Autoclaving is the best method to eradicate pathogens from surgical equipment because it involves subjecting the equipment to high temperature and pressure, which effectively kills all microorganisms, including bacteria, viruses, and spores. Autoclaving is a widely used sterilization method in healthcare settings as it ensures complete destruction of pathogens and is considered highly reliable and efficient.Rate this question:
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- 19.
Which of the following groups of antimicrobial agents permeabilized and depolarise the bacterial cell membrane and is active against gram-positive coccus:
- A.
Macrolides
- B.
Lincosamides
- C.
Lipoglycopeptides
- D.
Ketolides
- E.
Lipopeptides
Correct Answer
E. LipopeptidesExplanation
Lipopeptides are a group of antimicrobial agents that permeabilize and depolarize the bacterial cell membrane. They are active against gram-positive cocci. Macrolides, lincosamides, lipoglycopeptides, and ketolides are other groups of antimicrobial agents, but they do not have the same mechanism of action as lipopeptides. Therefore, the correct answer is lipopeptides.Rate this question:
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- 20.
A heterophile antibody test has been used to confirm a viral infection in adult patients. Most probably he was infected with:
- A.
Varicella-zoster virus
- B.
HIV
- C.
Measles virus
- D.
Rubella virus
- E.
Epstein-barr virus
Correct Answer
E. Epstein-barr virusExplanation
The correct answer is Epstein-barr virus. A heterophile antibody test is commonly used to diagnose Epstein-barr virus (EBV) infection, also known as infectious mononucleosis. This test detects antibodies that are produced by the immune system in response to EBV infection. The presence of heterophile antibodies indicates an active EBV infection. Varicella-zoster virus causes chickenpox and shingles, HIV causes AIDS, measles virus causes measles, and rubella virus causes rubella.Rate this question:
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- 21.
A 1 week-old baby was hospitalized due to suspicion of meningitis. Microbiological analysis of the CSF revealed gram-positive rods. Most likely the pathogen is:
- A.
Bacillus cereus
- B.
E.coli
- C.
Listeria monocytogenes
- D.
Clostridium spp.
- E.
Lactobacillus rhamnosus
Correct Answer
C. Listeria monocytogenesExplanation
Listeria monocytogenes is the most likely pathogen causing meningitis in a 1-week-old baby. This gram-positive rod bacterium is a common cause of meningitis in neonates and immunocompromised individuals. It can be transmitted to the fetus during pregnancy or acquired after birth through contaminated food or the environment. Listeria monocytogenes is known for its ability to cross the blood-brain barrier and cause meningitis. Other pathogens listed, such as Bacillus cereus, E.coli, Clostridium spp., and Lactobacillus rhamnosus, are not typically associated with neonatal meningitis.Rate this question:
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- 22.
Acute phase viremia in HIV-positive patients appears as:
- A.
Pneumocystis jiroveci pneumonia
- B.
Infectious mononucleosis
- C.
Kaposi's sarcoma
- D.
Shingles
- E.
Mononucleosis-like syndrome
Correct Answer
B. Infectious mononucleosis -
- 23.
Staphylococcal scalded skin syndrome is an acute epidermolysis caused by the staphylococcal exotoxin. Infants and children are most susceptible. exfoliative toxin A released from S.aures is encoded with
- A.
Staphylococcal pathogenicity island (SaPI)
- B.
MecA gene
- C.
Staphylococcal cassette chromosome SCC
- D.
Prophage
- E.
PlasmidÂ
Correct Answer
D. PropHageExplanation
Staphylococcal scalded skin syndrome is caused by the exotoxin released from Staphylococcus aureus. The exotoxin responsible for this condition, exfoliative toxin A, is encoded within the prophage. A prophage is a bacteriophage (virus that infects bacteria) that has integrated its DNA into the DNA of the host bacterium. In this case, the prophage carries the gene for exfoliative toxin A, which is responsible for causing the symptoms of staphylococcal scalded skin syndrome.Rate this question:
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- 24.
Transesophageal echocardiography was performed on a 56-year-old patient with dental problems and confirmed the suspected diagnosis of mitral valve infective endocarditis. The vegetation of 8mm was attached to the anteromedial segment of the anterior mitral valve leaf with irregular edges. Repetitive hemocultures were positive for a facultatively anaerobic, catalase-negative, resistant to optochin, gram-positive coccus. Which of the following microorganisms caused this infective endocarditis?
- A.
S.aures
- B.
Enterococcus faecium
- C.
S.pneumoniae
- D.
S. sanguinis
- E.
S. epidermidis
Correct Answer
D. S. sanguinisExplanation
The correct answer is S. sanguinis because it matches the description of the microorganism causing the infective endocarditis. S. sanguinis is a gram-positive coccus that is facultatively anaerobic, catalase-negative, and resistant to optochin. Additionally, it is commonly found in the oral cavity, which is consistent with the patient's dental problems.Rate this question:
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- 25.
Point at the most probable reservoir of influenza virus type A:
- A.
Humans
- B.
Birds
- C.
Horses
- D.
Rodents
- E.
Marine mammals
Correct Answer
B. BirdsExplanation
Birds are the most probable reservoir of influenza virus type A because they are known to carry various subtypes of the virus. Influenza A viruses can infect a wide range of bird species, including wild birds and domestic poultry. These viruses can then spread to humans and other animals through direct contact or through the exchange of bodily fluids. The high prevalence of influenza A in bird populations makes them a likely source of the virus.Rate this question:
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- 26.
Which of the following organisms are is strongly associated with Kaposi Sarcoma?
- A.
Helicobacter pylori
- B.
Epstein-Barr virus (EBV)
- C.
Human papillomavirus
- D.
JC polyomavirus
- E.
Human herpesvirus type 8
Correct Answer
E. Human herpesvirus type 8Explanation
Human herpesvirus type 8 is strongly associated with Kaposi Sarcoma. Kaposi Sarcoma is a type of cancer that affects the blood vessels and causes tumors to develop in various parts of the body. Human herpesvirus type 8 is known to be the primary cause of Kaposi Sarcoma, as it infects the cells lining the blood vessels and promotes the growth of abnormal blood vessels. This virus is commonly found in individuals with weakened immune systems, such as those with HIV/AIDS.Rate this question:
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- 27.
Which of the following gram-negative rods is a cause of serious UTI and produces urease that hydrolyses urea to CO2 and ammonia
- A.
Proteus vulgaris
- B.
Enterobacter cloacae
- C.
Citrobacter freundii
- D.
Shigella sonnei
- E.
E.coli
Correct Answer
B. Enterobacter cloacaeExplanation
Enterobacter cloacae is a gram-negative rod that is known to cause serious urinary tract infections (UTIs). It produces an enzyme called urease, which hydrolyses urea to produce carbon dioxide (CO2) and ammonia. This ability to produce urease is important because it allows Enterobacter cloacae to survive and thrive in the urinary tract, where urea is present. The production of ammonia by the hydrolysis of urea can increase the pH of the urine, creating an environment that is more favorable for bacterial growth and colonization.Rate this question:
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- 28.
A 29-year-old pregnant woman from Vietnam suffers from fulminant hepatitis caused by a viral infection. She needs liver transplantation immediately. Point at the most probable liver disease:
- A.
Hep E
- B.
Hep C
- C.
Hep B
- D.
Hep D
- E.
Hep A
Correct Answer
D. Hep DExplanation
Hepatitis D (Hep D) is caused by the hepatitis D virus, which can only infect individuals who are already infected with hepatitis B virus (HBV). It is transmitted through contact with infected blood or other bodily fluids. Fulminant hepatitis is a severe form of hepatitis characterized by rapid liver failure. In this case, the woman is pregnant, and pregnant women with chronic HBV infection are at an increased risk of developing fulminant hepatitis D. Therefore, Hep D is the most probable liver disease in this scenario.Rate this question:
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- 29.
For which of the following risk factors associated with neonatal infection there is the current recommendation to screen pregnant women by using a culture of vagina:
- A.
E.coli
- B.
Enterococcus faecium
- C.
Streptococcus agalactiae
- D.
Listeria monocytogenes
- E.
Staphylococcus aures
Correct Answer
C. Streptococcus agalactiaeExplanation
Streptococcus agalactiae, also known as Group B Streptococcus (GBS), is a common cause of neonatal infection. It can be transmitted from mother to baby during childbirth, leading to serious complications such as pneumonia, sepsis, and meningitis. Therefore, it is recommended to screen pregnant women for GBS colonization using a vaginal culture. This allows for early detection and appropriate interventions, such as administration of antibiotics during labor, to reduce the risk of neonatal infection.Rate this question:
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- 30.
The patient was diagnosed with actinomycosis. The gram stain of sputum revealed:
- A.
Gram-positive cocci in clusters
- B.
Gram-negative rods in spores
- C.
Gram-negative branched rods
- D.
Gram-positive branched rods
- E.
Gram-negative short rods
Correct Answer
D. Gram-positive branched rodsExplanation
The presence of gram-positive branched rods in the gram stain of the sputum suggests a diagnosis of actinomycosis. Actinomycosis is a bacterial infection caused by Actinomyces species, which are gram-positive, filamentous bacteria that form branching rods. This infection commonly affects the oral cavity, lungs, and abdomen. The identification of gram-positive branched rods in the gram stain is consistent with the characteristic morphology of Actinomyces species, supporting the diagnosis of actinomycosis.Rate this question:
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- 31.
CSF sample was microbiologically investigated: The following parameters have been found: Neutrophiles - 10 000/mL (NR: 0-5 cells/mL) Protein concentration > 140 mg/dL (NR: 15-25 mg/dL) Glucose concentration < 20 mg/dL (NR: 45-85 mg/dL) you may suspect:
- A.
Varicella-zoster virus meningitis
- B.
Mycobacterial meningitis
- C.
Streptococcus pneumoniae meningitis
- D.
Leptospira interrogans meningitis
- E.
Herpes simples virus meningitis
Correct Answer
C. Streptococcus pneumoniae meningitisExplanation
Based on the CSF sample findings, the neutrophil count is significantly elevated, which is indicative of an acute bacterial infection. The protein concentration is also significantly elevated, suggesting inflammation. Additionally, the glucose concentration is significantly decreased, which is consistent with bacterial meningitis. Among the given options, Streptococcus pneumoniae is a common cause of bacterial meningitis and is known to cause these specific CSF findings. Therefore, Streptococcus pneumoniae meningitis is the most likely explanation for the CSF sample findings.Rate this question:
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- 32.
Which of the following toxins stimulates adenylate cyclase activity and increases cAMP concentration throughout the small intestine, which results in the efflux of ions and water into the intestinal lumen?
- A.
Listeriolysin O
- B.
Shiga toxin from Shigella dysenteriae type 1
- C.
Heat-labile enterotoxin (LT) from E.coli
- D.
Cereulide from bacillus cereus
Correct Answer
C. Heat-labile enterotoxin (LT) from E.coliExplanation
Heat-labile enterotoxin (LT) from E.coli stimulates adenylate cyclase activity and increases cAMP concentration throughout the small intestine. This leads to the efflux of ions and water into the intestinal lumen.Rate this question:
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- 33.
Measles vaccine:
- A.
Live
- B.
Live attenuated
- C.
Recombinant
- D.
Killed/ inactivated
Correct Answer
B. Live attenuatedExplanation
The correct answer is "live attenuated." This means that the measles vaccine contains a weakened form of the live virus. This weakened virus is still able to stimulate an immune response in the body, but it is not strong enough to cause the disease itself. This type of vaccine provides long-lasting immunity and is typically given in two doses to ensure effectiveness.Rate this question:
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- 34.
Which of the following infections needs paired serum samples to be confirmed:
- A.
Anthrax
- B.
Strep angina
- C.
Bacterial vaginosis
- D.
Measles
- E.
Scarlet fever
Correct Answer
D. MeaslesExplanation
Measles is the correct answer because it is an infectious disease that requires paired serum samples to be confirmed. Paired serum samples are collected from the patient during the acute phase of the infection and then again during the convalescent phase, typically 10-14 days later. The samples are tested for the presence of measles-specific IgM and IgG antibodies. The presence of a significant rise in antibody levels between the acute and convalescent samples confirms the diagnosis of measles. This method is necessary because a single serum sample may not provide enough information to accurately diagnose measles.Rate this question:
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- 35.
Surgical site infections (SSIs) are defined as infectious occurring up to 30 days after surgery (or up to one year after surgery in patients receiving implants) and affecting either the incision or deep tissue at the operation site. Which of the following the most common isolated organisms from SSIs?
- A.
Enterococcus
- B.
Alpha-haemolytic streptococcus
- C.
Beta-haemolytic streptococcus
- D.
Coagulase-positive coccus
- E.
Coagulase-negative coccus
Correct Answer
E. Coagulase-negative coccusExplanation
Coagulase-negative cocci are the most common isolated organisms from surgical site infections (SSIs). These bacteria are often found on the skin and can enter the surgical site during surgery. They are a common cause of postoperative infections, particularly in patients with implanted devices. Coagulase-negative cocci are known for their ability to form biofilms, which can protect them from antibiotics and the immune system, making them difficult to treat. Therefore, it is important to identify and target these organisms in order to prevent and manage SSIs effectively.Rate this question:
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- 36.
Gardasil and Cervarix are the vaccines against"
- A.
Haemophilus ducreyi
- B.
Klebsiella granulomatis
- C.
Human papillomavirus
- D.
Hepatitis B virus
- E.
HIV
Correct Answer
C. Human papillomavirusExplanation
Gardasil and Cervarix are vaccines that protect against Human papillomavirus (HPV). HPV is a sexually transmitted infection that can cause various types of cancers, including cervical, vaginal, vulvar, anal, penile, and oropharyngeal cancers. These vaccines are designed to prevent the transmission of HPV and reduce the risk of developing these types of cancers. They are recommended for both males and females, typically given in early adolescence before individuals become sexually active. By targeting HPV, these vaccines have the potential to significantly reduce the prevalence of HPV-related diseases and improve public health.Rate this question:
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- 37.
Shigellosis produces inflammatory reactions and ulceration on the intestinal epithelium followed by blood or mucoid diarrhea. Which of the following pathotypes of diarrheagenic E.coli is biochemically, genetically, and pathologically related to Shigella spp, and causes similar clinical symptoms?
- A.
EIEC
- B.
EAEC
- C.
EHEC
- D.
EPEC
- E.
ETEC
Correct Answer
C. EHECExplanation
EHEC (Enterohemorrhagic Escherichia coli) is the correct answer. EHEC is biochemically, genetically, and pathologically related to Shigella spp. It causes similar clinical symptoms, including inflammatory reactions, ulceration on the intestinal epithelium, and blood or mucoid diarrhea. EHEC is known for producing Shiga toxins, which contribute to its pathogenicity.Rate this question:
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- 38.
Point at the virulence factor playing a crucial role in pneumonia caused by Haemophilus influenza:
- A.
Capsule
- B.
Beta-haemolysin
- C.
Tracheal cytotoxin
- D.
Lecintinase
- E.
Exfoliative toxin
Correct Answer
A. CapsuleExplanation
The correct answer is "Capsule". The capsule is a virulence factor that plays a crucial role in pneumonia caused by Haemophilus influenza. The capsule helps the bacteria evade the host's immune system by preventing phagocytosis, allowing the bacteria to establish infection in the respiratory tract. It also helps the bacteria adhere to respiratory epithelial cells and form biofilms, leading to the development of pneumonia.Rate this question:
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- 39.
Point at the filterable particles:
- A.
Haemophilic rods
- B.
Mycolic acid - containing microorganisms
- C.
Spore forming pathogens
- D.
Facultatively intracellular meningococci
- E.
Parainfluenza viruses
Correct Answer
A. HaemopHilic rodsExplanation
Haemophilic rods are pointed at as the filterable particles because they are a type of bacteria that can pass through filters due to their small size. This characteristic allows them to be separated and studied in laboratory settings.Rate this question:
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- 40.
Spreading of bacteria on the solid medium because of the presence of high numbers of flagella is typical of:
- A.
Pseudomonas aeruginosa
- B.
Staphylococcus aures
- C.
Proteus mirabilis
- D.
Enterococcus faecalis
- E.
Actinomyces israelii
Correct Answer
C. Proteus mirabilisExplanation
The correct answer is Proteus mirabilis. Proteus mirabilis is a motile bacterium that is known for its swarming behavior on solid surfaces. This swarming behavior is facilitated by the presence of numerous flagella on the bacterial cells. The flagella allow the bacteria to move rapidly across the solid medium, leading to the characteristic spreading pattern observed with Proteus mirabilis.Rate this question:
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- 41.
When you take the blood samples from the patient suspected to have a bloodstream infection due to high fever and elevated procalcitonin level, you may expect the growth of"
- A.
E.coli in at least 2 blood samples
- B.
S.epidermidis, S.aures, E.faecalis, and Acinetobacter baumanii in one sample
- C.
S.epidermidis in one blood sample
- D.
S.epidermidis in the first sample, S.aures in the second sample, E.faecalis in the third sample, and Acinetobacter baumanii in the fourth sample
- E.
Mycobacterium leprae and Mycobacterium tuberculosis in one sample
Correct Answer
C. S.epidermidis in one blood sample -
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Current Version
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Mar 22, 2023Quiz Edited by
ProProfs Editorial Team -
Feb 22, 2021Quiz Created by
Catherine Halcomb
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