Question 1

Which bacterial species is the primary causative agent of acne, and what is its Gram stain classification?

Accepted Answer

Propionibacterium acnes, Gram positive rod

Question 2

A patient presents with a cluster of encapsulated boils that are slow to heal and likely to leave scars. Which condition is most consistent with these symptoms, and what is the recommended treatment?

Accepted Answer

Carbuncle; lancing and draining

Question 3

Which of the following is a major complication of untreated cellulitis?

Accepted Answer

Necrotizing fasciitis ('flesh-eating strep')

Question 4

A child presents with a honey-colored crusted rash on the face. What is the most likely diagnosis and causative agent?

Accepted Answer

Impetigo; Staphylococcus aureus or Streptococcus pyogenes

Question 5

Which of the following is the most common causative agent of burn infections in hospitalized patients?

Accepted Answer

Pseudomonas aeruginosa

Question 6

A patient from India presents with thickened skin, loss of facial features, and claw-like deformities of the hands. Which disease is most likely responsible, and what is the causative agent?

Accepted Answer

Hansen’s Disease (Leprosy); Mycobacterium leprae

Question 7

Which of the following treatments is reserved for the most severe forms of acne?

Accepted Answer

Accutane (isotretinoin)

Question 8

A patient presents with a pale pink rash on the trunk that spreads to the extremities, mild cold symptoms, and swollen lymph nodes. Which viral disease is most likely, and what is a major complication for pregnant women?

Accepted Answer

Rubella; birth defects due to fetal capillary damage

Question 9

Which equation best describes the rate of spread of a contagious skin disease in a population, assuming direct contact transmission?

Accepted Answer

$$\frac{dI}{dt} = \beta SI - \gamma I$$

Question 10

A patient develops a strip-like pattern of blister-like lesions on one side of the body, accompanied by severe pain. Which disease is most likely, and what is the causative agent?

Accepted Answer

Shingles; Varicella-Zoster Virus

Question 11

Which of the following is a distinguishing characteristic of smallpox lesions compared to chickenpox?

Accepted Answer

Smallpox lesions have a depression in the center

Question 12

Which of the following is the most effective prevention strategy for ringworm in communal environments?

Accepted Answer

Avoid sharing towels and keep skin dry

Question 13

A patient presents with noncancerous skin growths on the hands and fingers. Which virus is most likely responsible, and what is a common treatment?

Accepted Answer

Human papilloma virus (HPV); salicylic acid

Question 14

Which of the following is a major risk associated with oral terbinafine (Lamisil) for severe ringworm infections?

Accepted Answer

Rare cases of liver failure

Question 15

A newborn develops conjunctivitis 5-14 days after birth. Which causative agent is most likely, and what is the recommended prevention?

Accepted Answer

Chlamydia trachomatis; silver nitrate

Question 16

Which of the following is a key feature of trachoma that distinguishes it from other forms of conjunctivitis?

Accepted Answer

Repeated infections lead to corneal scarring and irreversible blindness

Question 17

Which of the following equations represents the probability of transmission of conjunctivitis in a population, given contact rate $$c$$ and probability of infection per contact $$p$$?

Accepted Answer

$$P = 1 - e$$^{-cp}$$

Question 18

Which of the following is the primary causative agent of keratitis, and what is a common treatment?

Accepted Answer

Herpes simplex virus; trifluridine eye drops

Question 19

A patient presents with itching, burning, and thickened skin between the toes after using a communal shower. Which condition is most likely, and what is the causative agent?

Accepted Answer

Tinea pedis (athlete’s foot); Trichophyton species

Question 20

Which of the following is a major public health concern regarding smallpox, despite its eradication?

Accepted Answer

Potential use as a bioterrorism agent

Microbial Diseases of the Skin and Eyes: Bacterial, Viral, and Fungal Infections

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