Nokea
A patient with a long history of chronic gastritis undergoes a gastroscopy, which detects an ulcer in the duodenum area. Microscopic examination of the tissue biopsy developed Gram-negative curved bacteria and the rapid urease activity test of the biopsy material was highly positive. The most likely cause of the disease is:
- A. Vibrio cholerae
- B. Campylobacter fetus
- C. Acinetobacter baumannii
- D. Helicobacter pylori
Correct Answer: D
Rationale: The correct answer is D: Helicobacter pylori. Helicobacter pylori is a known bacterium associated with causing duodenal ulcers. The presence of Gram-negative curved bacteria in the biopsy along with a highly positive rapid urease test is characteristic of H. pylori infection. Vibrio cholerae causes cholera, not duodenal ulcers. Campylobacter fetus is associated with gastroenteritis, not duodenal ulcers. Acinetobacter baumannii is a nosocomial pathogen, not typically associated with duodenal ulcers. In summary, the unique combination of findings in this case points towards H. pylori as the most likely cause of the disease.
You may also like to solve these questions
Patients planned for treatment with monoclonal antibodies are tested for:
- A. HBV
- B. HCV
- C. M. tuberculosis
- D. All are correct
Correct Answer: D
Rationale: The correct answer is D: All are correct. Patients planned for treatment with monoclonal antibodies should be tested for HBV, HCV, and M. tuberculosis due to the risk of reactivation of these infections during treatment. HBV and HCV reactivation can lead to severe liver damage, while M. tuberculosis reactivation can cause serious respiratory complications. Testing for all three infections helps in identifying and managing any pre-existing infections to ensure patient safety during monoclonal antibody treatment. Choices A, B, and C are incorrect because each of these infections presents specific risks that need to be assessed before initiating monoclonal antibody therapy.
An 18-year-old patient has enlarged inguinal lymph nodes, they are painless, thickened on palpation. In the area of genital mucous membrane there is a small-sized ulcer with thickened edges and "laquer"bottom of greyish colour. What is the most probable diagnosis?
- A. Syphilis
- B. Tuberculosis
- C. Lepra
- D. Trophic ulcer
Correct Answer: A
Rationale: The correct answer is A: Syphilis. The presentation of painless inguinal lymph nodes, along with a small-sized ulcer with thickened edges and a "laquer" bottom of greyish color on the genital mucous membrane, is classic for primary syphilis. The painless nature of the lymph nodes and the specific characteristics of the ulcer are key features of syphilitic infection. Primary syphilis is caused by the bacterium Treponema pallidum and typically presents with a single, painless ulcer known as a chancre. It is important to consider syphilis in the differential diagnosis of genital ulcers.
Summary of other choices:
B: Tuberculosis - Unlikely, as tuberculosis typically presents with pulmonary symptoms and does not cause genital ulcers.
C: Lepra - Unlikely, as leprosy does not typically present with painless inguinal lymph nodes and the specific ulcer characteristics described.
D: Trophic ulcer - Unlikely
Which of the following organisms produces aflatoxin, a carcinogenic substance?
- A. Candida albicans
- B. Claviceps purpurea
- C. Aspergillus flavus
- D. Staphylococcus aureus
Correct Answer: C
Rationale: Step-by-step rationale:
1. Aspergillus flavus is a fungus known to produce aflatoxin.
2. Aflatoxin is a potent carcinogen found in contaminated food.
3. Candida albicans is a yeast species not associated with aflatoxin production.
4. Claviceps purpurea is a fungus that produces ergot alkaloids, not aflatoxin.
5. Staphylococcus aureus is a bacterium known for causing food poisoning, not aflatoxin production.
Summary: Aspergillus flavus is the correct answer as it is the organism known to produce aflatoxin, a carcinogenic substance. Other choices are incorrect as they are not associated with aflatoxin production.
Which bacteria are responsible for causing the disease tuberculosis?
- A. Mycobacterium leprae
- B. Streptococcus pneumoniae
- C. Mycobacterium tuberculosis
- D. Clostridium botulinum
Correct Answer: C
Rationale: The correct answer is C: Mycobacterium tuberculosis. This bacterium is responsible for causing tuberculosis as it specifically infects the lungs and can spread to other parts of the body. Mycobacterium leprae (A) causes leprosy, Streptococcus pneumoniae (B) causes pneumonia, and Clostridium botulinum (D) causes botulism, making them incorrect choices for tuberculosis. Mycobacterium tuberculosis has unique characteristics and mechanisms that enable it to cause tuberculosis, such as its ability to evade the immune system and form granulomas in the lungs.
When a smear is stained by Burri-Gins method a mucous structure that is tightly bound with the cellular wall of bacteria and has well-defined outer boundaries can be detected. This element of a bacteria cell is called:
- A. Capsule
- B. Spore
- C. Filaments
- D. Ribosomes
Correct Answer: A
Rationale: The correct answer is A: Capsule. A capsule is a mucous structure tightly bound to the bacterial cell wall with distinct outer boundaries. This structure helps bacteria evade the host immune system, resist desiccation, and adhere to surfaces. In contrast, spores are resistant structures formed by certain bacteria for survival, filaments are long chains of bacterial cells, and ribosomes are cellular organelles responsible for protein synthesis. Therefore, based on the characteristics described in the question, the most appropriate choice is A: Capsule.