Which bacteria are associated with causing urinary tract infections?

Correct Answer: D

Rationale: The correct answer is D, "All of the above," because all three bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) can cause urinary tract infections. E. coli is the most common causative agent of UTIs, followed by Staphylococcus aureus and occasionally Pseudomonas aeruginosa. Each of these bacteria has different virulence factors that enable them to infect the urinary tract. Therefore, it is important to consider all three options when diagnosing and treating UTIs. Choices A, B, and C are incorrect because each of those bacteria can individually cause UTIs, so the correct answer is D, as it encompasses all the possible causative agents.

Correct Answer: B

Rationale: The correct answer is B: Malaria. Fever developing 2 weeks post-blood transfusion is characteristic of malaria due to the incubation period of the parasite. Trypanosomiasis presents earlier, amebiasis usually causes GI symptoms, and toxoplasmosis typically manifests with flu-like symptoms. Malaria is the most likely cause based on the timing and clinical presentation.

Correct Answer: D

Rationale: The correct answer is D, "All of the above," because all three bacteria (Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) can cause urinary tract infections. E. coli is the most common causative agent of UTIs, followed by Staphylococcus aureus and occasionally Pseudomonas aeruginosa. Each of these bacteria has different virulence factors that enable them to infect the urinary tract. Therefore, it is important to consider all three options when diagnosing and treating UTIs. Choices A, B, and C are incorrect because each of those bacteria can individually cause UTIs, so the correct answer is D, as it encompasses all the possible causative agents.

Correct Answer: B

Rationale: The correct answer is B because the presence of calcium dipicolinate in bacterial spores helps protect their DNA from damage under harsh conditions. Calcium dipicolinate acts as a stabilizer, preserving the spore structure. Choice A is incorrect as bacterial spores have a tough protein coat, not a lipid-rich membrane. Choice C is incorrect as bacterial spores have very low metabolic activity. Choice D is incorrect as bacterial spores have low water content to prevent damage during harsh conditions.

Correct Answer: D

Rationale: The correct answer is D: Chlamydia trachomatis. Lymphogranuloma venereum (LGV) is caused by Chlamydia trachomatis serovars L1, L2, and L3. These serovars infect the lymphatic system leading to swelling and inflammation. Choice A, Chlamydia pneumoniae, is associated with respiratory infections, not LGV. Choice B, Chlamydia psittaci, causes psittacosis in birds and humans. Choice C, Mycoplasma genitalium, is a separate STI but is not the causative agent for LGV. The key to the correct answer is understanding the specific pathogen responsible for LGV based on its clinical presentation and mode of transmission.

Correct Answer: A

Rationale: The correct answer is A: Oxacillin. In AST for Gram-positive bacteria, the antibiotic panel typically includes oxacillin to determine if the bacterium is susceptible or resistant to beta-lactam antibiotics. Oxacillin is commonly used to test for methicillin resistance in Staphylococcus aureus. Tetracycline (B), Tobramycin (C), and Amikacin (D) are not typically included in the Gram-positive antibiotic panel. Tetracycline is more commonly used for Gram-negative bacteria, while Tobramycin and Amikacin are aminoglycosides usually tested in Gram-negative bacterial infections. Therefore, they are not appropriate choices for the Gram-positive antibiotic panel.

Correct Answer: B

Rationale: The correct answer is B: Thermophiles. Thermophiles are bacteria that can survive in extreme temperatures, typically between 45°C to 80°C. This ability is due to their unique enzymes and cell membrane structures that are adapted to high temperatures. Escherichia coli (A) is a common bacterium found in the human gut and does not thrive in extreme temperatures. Clostridium tetani (C) is a bacterium that causes tetanus and prefers moderate temperatures. Salmonella enterica (D) is a pathogenic bacterium that does not thrive in extreme temperatures. Therefore, Thermophiles are the only bacteria on the list known for surviving in extreme temperatures.

Correct Answer: B

Rationale: The correct answer is B: Fluconazole. Rationale: 1. Candidiasis is a fungal infection, so an antimycotic agent is needed. 2. β-lactam antibiotics like ampicillin can lead to fungal overgrowth, necessitating an antimycotic. 3. Fluconazole is an antifungal agent effective against Candida species. 4. Streptomycin is an antibiotic, not an antifungal. 5. Phthalylsulfathiazole is an antibacterial sulfonamide, not an antifungal. 6. Ampicillin is an antibiotic, not an antifungal.

Correct Answer: D

Rationale: The correct answer is D because fungi do not form flagella. Fungi reproduce sexually and asexually (A) through spores, have a cell wall (B) made of chitin, and are mostly aerobic or facultative anaerobes (C). Flagella are structures found in some protozoa and bacteria, not in fungi. Therefore, option D is the only statement that is not true about fungi.