What preventive medications should be injected to a patient with open maxillofacial trauma provided that he has never got prophylactic vaccination before?

Correct Answer: C

Rationale: Step 1: Antitetanus serum is crucial for patients with open maxillofacial trauma to prevent tetanus infection from contaminated wounds. Step 2: Antibiotics are needed to prevent infection in the wound. Step 3: Antitetanus serum provides immediate passive immunity while antibiotics help combat potential infections. Step 4: Antitetanus immunoglobulin is not mentioned in the question and is not typically used for prophylaxis. Step 5: Anticonvulsive drugs are not preventive medications for maxillofacial trauma. Step 6: Diphtheria, tetanus, and pertussis vaccines are not specifically indicated for immediate prevention in this scenario.

Correct Answer: A

Rationale: The correct answer is A: Bordetella. The presence of mercury-drop like colonies on Bordet-Gengou agar indicates Bordetella pertussis. The small ovoid gram-negative bacilli sized 1-3 microns are characteristic of Bordetella species. Catarrhal symptoms are typical of pertussis caused by Bordetella pertussis. Summary of other choices: B: Corynebacteria do not typically exhibit mercury-drop like colonies or small ovoid shapes. C: Mycobacteria are acid-fast bacilli and do not grow on Bordet-Gengou agar. D: Meningococcus is a gram-negative diplococcus and does not match the description provided.

Correct Answer: A

Rationale: The correct answer is A: Leptospira interrogans. Darkfield microscopy is used to visualize spirochetes, which are spiral-shaped bacteria. Leptospira is a spirochete bacterium that causes leptospirosis, which presents with jaundice, muscle aching, chill, and nosebleeds. Leptospira is commonly transmitted through contact with contaminated water or soil. B: Borrelia dutlonii causes Lyme disease, which is transmitted by ticks and does not typically present with jaundice or nosebleeds. C: Calymmatobacterium granulomatis causes granuloma inguinale, a sexually transmitted infection that does not present with the symptoms described. D: Bartonella bacilloformis causes Carrion's disease, which presents with fever, anemia, and skin lesions but not jaundice or nosebleeds.

Correct Answer: A

Rationale: The correct answer is A: Metronidazole. Amebic dysentery is caused by the parasite Entamoeba histolytica, not bacteria. Metronidazole is the drug of choice for treating this parasitic infection. It works by disrupting the DNA structure of the parasite, leading to its death. Mebendazole (B) is used to treat certain worm infections, not amebic dysentery. Itrakonazole (C) is an antifungal medication and not effective against parasites. Furacillin (D) is an antibacterial agent and not suitable for treating parasitic infections like amebic dysentery.

Correct Answer: A

Rationale: The correct answer is A: Trichomonas vaginalis. Trichomonas vaginalis is a flagellated protozoan that causes trichomoniasis, a sexually transmitted infection commonly found in vaginal discharges. In this case, the presence of flagellates in the vaginal discharge aligns with the characteristics of Trichomonas vaginalis. Leishmania donovani causes leishmaniasis, transmitted by sandflies. Trypanosoma gambiense causes African sleeping sickness through the tsetse fly bite. Trihomonas hominis is a non-pathogenic flagellate found in the human intestine. Therefore, the correct choice is A due to the correlation between the flagellates found in the vaginal discharge and the characteristics of Trichomonas vaginalis.