A Gram-stained smear from a wound revealed Gram-positive rods with terminal spores. The bacteria were anaerobic and produced gas. What is the most likely causative agent?
- A. Clostridium perfringens
- B. Bacillus anthracis
- C. Clostridium botulinum
- D. Clostridium tetani
Correct Answer: A
Rationale: The correct answer is A: Clostridium perfringens. This bacterium is an anaerobic, Gram-positive rod that forms terminal spores and produces gas. It is commonly associated with wound infections and gas gangrene. Clostridium botulinum causes botulism and does not typically present with gas production. Bacillus anthracis is an aerobic, Gram-positive spore-forming bacterium causing anthrax. Clostridium tetani causes tetanus and does not produce gas. Thus, based on the characteristics described in the question, Clostridium perfringens is the most likely causative agent.
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The patient 25 y.o. was admitted on the 1st day of the disease with complaints of double vision in the eyes, heavy breathing. The day before the patient ate homemade mushrooms. On objective examination: paleness, widened pupils, disorder of swallowing, bradycardia, constipation are marked. What is the diagnosis?
- A. Botulism
- B. Yersiniosis
- C. Leptospirosis
- D. Salmonellosis, gastrointestinal form
Correct Answer: A
Rationale: The correct answer is A: Botulism. Botulism is a rare but serious illness caused by a toxin produced by the bacterium Clostridium botulinum. In this case, the patient's symptoms align with botulism due to the ingestion of homemade mushrooms. The symptoms of double vision, heavy breathing, paleness, widened pupils, swallowing difficulties, bradycardia, and constipation are all classic signs of botulism poisoning. The toxin affects the nervous system and can lead to paralysis. The other choices (B: Yersiniosis, C: Leptospirosis, D: Salmonellosis) do not match the patient's symptoms and history of consuming mushrooms, making them incorrect.
Methods typically used to diagnose bacterial infections of the reproductive system include:
- A. microscopic examination of discharge from infected organ and microscopic examination of urine for organisms
- B. biopsy of infected tissue and use of selective media
- C. microscopic examination of fecal sample and protein test of urine
- D. antibody agglutination test and coagulation test
Correct Answer: A
Rationale: Step-by-step rationale for choice A being correct:
1. Microscopic examination of discharge from infected organ allows direct visualization of bacteria causing the infection.
2. Microscopic examination of urine for organisms can help identify any bacteria present in the urinary tract.
3. Both methods are specific for diagnosing bacterial infections in the reproductive system.
Summary:
- Choice B is incorrect as biopsy is invasive and not typically used for diagnosing bacterial infections.
- Choice C is incorrect as fecal samples and urine protein tests are not relevant for diagnosing bacterial infections in the reproductive system.
- Choice D is incorrect as antibody agglutination and coagulation tests are not primary methods for diagnosing bacterial infections in the reproductive system.
Toxoplasma gondii belongs to which group of eukaryotic organisms?
- A. Algae
- B. Fungi
- C. Protozoans
- D. Helminths
Correct Answer: C
Rationale: Toxoplasma gondii is a protozoan parasite known to cause toxoplasmosis. It belongs to the group of eukaryotic organisms called protozoans because it is a single-celled organism with complex cellular structures. Protozoans are characterized by their ability to move and perform essential functions independently. Algae (choice A) are photosynthetic eukaryotic organisms, fungi (choice B) are non-photosynthetic eukaryotes that include molds and yeasts, and helminths (choice D) are multicellular parasitic worms. Therefore, the correct answer is C because Toxoplasma gondii is a protozoan parasite.
The patient has developed pain in the axillary area, rise of temperature developed 10 hours ago. On examination: shaky gait is marked, the tongue is coated by white coating. The pulse is frequent. The painful lymphatic nodules are determined in the axillary area. The skin is erythematous and glistering over the lymphatic nodules. What is the most probable diagnosis?
- A. Bubonic plague
- B. Acute purulent lymphadenitis
- C. Lymphogranulomatosis
- D. Tularemia
Correct Answer: D
Rationale: The most probable diagnosis is D: Tularemia. Tularemia is a bacterial infection caused by Francisella tularensis. The symptoms described align with tularemia, such as pain in axillary area, fever, shaky gait, coated tongue, frequent pulse, painful lymphatic nodules, and erythematous skin over nodules. The key features pointing towards tularemia are the presence of lymphadenitis in the axillary area and the erythematous, glistering skin over the nodules, which are characteristic of ulceroglandular tularemia. Bubonic plague (A) presents with painful, swollen lymph nodes called buboes but typically lacks the erythematous skin findings. Acute purulent lymphadenitis (B) usually presents with pus-filled lymph nodes but does not typically cause shaky gait or coated tongue. Lymphogranulomatosis (C) is a term for Hodgkin's lymphoma, which does not
Compared to primary immune response the secondary immune response
- A. 1. Is quicker
- B. 2. Produces much more antibodies
- C. 3. Requires more antigen stimulations
- D. 4. Is slower
Correct Answer: A
Rationale: The correct answer is A because the secondary immune response is quicker due to memory B and T cells being already present from the primary response. These memory cells can quickly recognize and respond to the antigen upon re-exposure, leading to a faster and more efficient immune response. Choices B and C are incorrect as the secondary response produces more antibodies and requires fewer antigen stimulations. Choice D is also incorrect as the secondary response is faster than the primary response.