Block 15 Bacterial Viral Fungal Skin Lesions

20 Questions | By Chachelly | Updated: Mar 21, 2022 | Attempts: 739

Questions

Settings

Block 15 Bacterial Viral Fungal Skin Lesions - Quiz

CTL: Cutaneous/ SubQ Mycoses CTL: Inflammatory skin diseases; viral exanthems and enanthems; skin path CTL: Patient with rash; skin flora, bacterial infections; zoonotic infections

Questions and Answers

1.

A 22-year-old presents with a toenail that concerns her. What would you expect to see in the microscope? Note some are stained
- A.
- B.
- C.
- D.
- E.
2.

A 57-year-old oncologist who is also an avid gardener presents with a swollen series of three nodules on his left hand. He says that he believes they started from some trauma acquired from poking himself while picking limes off of his tree. (Lime trees have spiny little branches.) He remembers from medical school that there was some fungus that was common on plant material that could start these infections and that it had a shared characteristic with some of the systemic fungal pathogens. What is the most likely causative agent?
- A.
  
  Histoplasma capsulatum
- B.
  
  Candida albicans
- C.
  
  Actinomyces israeli
- D.
  
  Malassezia furfur
- E.
  
  Sporothrix schenckii
3.

Your patient is a sportsman who plays racket ball at a local club, softball, and hockey in the winter. The patient presents with a pruritic, erythematous, moist, rash on his groin. The infected area is the skin on the upper thigh and especially folds on the lower abdomen; both the scrotum and penis are spared. What is the most likely causative agent of this patient’s condition?
- A.
  
  Sporothrix schenkii
- B.
  
  Trichophyton schoenleinii
- C.
  
  Trichophyton rubrum
- D.
  
  Candida albicans
4.

A six year-old boy presents with complaints of itchy head. Two weeks ago, he was treated by a nurse clinician for a sore throat. On closer examination, you find small scaling patches of hair on three different areas. These are not significantly inflamed, nor is there exudate present but there appear to be fewer hairs in these patches and the hair color appears to be somewhat hypopigmented. The hairs fluoresce under the Wood's lamp. There is nothing obvious attached to the hairs. What is the most likely diagnosis?
- A.
  
  Nits and lice acquired from shared baseball caps, brushes and combs
- B.
  
  Tinea capitis from shared caps, brushes and combs
- C.
  
  Candida spp. from antibiotic administration for pharyngitis
- D.
  
  Ringworm from a neighbor's dog
- E.
  
  Measles from respiratory route from a second unvaccinated child
5.

A 44-year-old woman presented to a dermatologist with a 3-month history of painless, splotchy hypopigmentation on her back and arms. The skin fluoresced under a Wood’s lamp. The diagnosis was tinea versicolor. What caused it?
- A.
  
  Tinea corporis
- B.
  
  Actinomyces
- C.
  
  Erysipelothrix
- D.
  
  Malassezia furfur
6.

A 40-year-old Caucasian female presents with a complaint of rash that has developed over the last several weeks and seems to be progressing. On examination, she is noted to have several lesions over the extensor surfaces of both upper and lower extremities as well as similar lesions on her scalp. The macroscopic and microscopic appearance of the lesion is shown for you evaluation below. Which of the following is the most likely diagnosis?
- A.
  
  Lichen planus
- B.
  
  Psoriasis
- C.
  
  Eczema
- D.
  
  Discoid lupus erythematosus
7.

A 33-year-old Caucasian male visits his dermatologist complaining of painful, blistering skin lesions over his back, chest, and arms that break down and leave denuded skin areas. On questioning, he reports that over the past few years he has had large recurrent aphtous ulcers in the mouth. He was not taking any drugs before his symptoms developed. Physical examination reveals large aphtous ulcers over oral mucosa and large bullous skin lesions. Vertical pressure over bullae leads to lateral expansion; skin over bullae peels like that of “hot tomato”. The gross and microscopic appearance of the lesion is presented in the images below.
- A.
  
  Bullous pemphigoid
- B.
  
  Pemphigus vulgaris
- C.
  
  Dermatitis herpetiformis
- D.
  
  Erythema multiforme
8.

A 13-year-old girl is seen in the emergency department with a rash covering her entire body consisting of itchy blisters in various stages. The rash had appeared first on the trunk and face after the girl had been “sick with the flu”. What is the structure of the viral genome of the virus most likely causing this disease?
- A.
  
  Negative sense, single-stranded RNA
- B.
  
  Positive sense, single-stranded RNA
- C.
  
  Either positive- or negative-sense, single-stranded DNA
- D.
  
  Double-stranded RNA
- E.
  
  Double-stranded DNA
9.

Measles is making something of a resurgence in some Western countries due to lack of vaccination. It is often said that the typical symptoms of measles, in addition to Koplik’s spots, are the 3 C’s (plus P). What does this mean?
- A.
  
  Cough, coryza, conjunctivitis (+ photophobia)
- B.
  
  Colic, cough, cachexia (+ pimples)
- C.
  
  Colic, caecitis, cough (+ purulence)
- D.
  
  Cough, coryza, child (+ polymorphonuclear cells)
10.

A 3-year-old boy in Brazil, who had not received MMR vaccine, developed fever followed by a diffuse maculo-papular erythematous rash. His pediatrician suspected rubeola caused by measles virus or fifth disease caused by parvovirus B19. These two viruses differ in which respects?
- A.
  
  One has a single-stranded genome, the other a double-stranded genome
- B.
  
  One has DNA, the other has RNA; one is enveloped, the other is naked
- C.
  
  One has DNA, the other has RNA; both are enveloped
- D.
  
  Both have RNA; one is enveloped, the other is naked
11.

A 6-year old child is seen with a prominent bright red rash that appeared 2 days earlier on the cheeks. The child has a sore throat and a low-grade fever. Which of the following statements describes most accurate the major site of viral replication of the infectious agent?
- A.
  
  Lymphocytes and monocytes
- B.
  
  Erythroid progenitor cells
- C.
  
  Epithelial cells and endothelial cells
- D.
  
  Neurons
- E.
  
  Osteoblasts and chondroblasts
12.

An 11-year-old boy bas a benign growth on his foot that is characterized by hyperplasia of the prickle cells. What of the following the most likely cause of the growth?
- A.
  
  Fungus that exhibits septate hyphae and is not thermally dimorphic
- B.
  
  Virus whose replication is dependent on the epithelial cell differentiation stage
- C.
  
  Fungus that metabolizes keratin
- D.
  
  Large, enveloped, linear double-stranded DNA virus
- E.
  
  Virus that replicates in most tissue culture cells
13.

The skin lesion shown would be best described as a/an:
- A.
  
  Plaque
- B.
  
  Macule
- C.
  
  Papule
- D.
  
  Patch
- E.
  
  Pustule
14.

This 25 -year-old female presents with a long history of an intermittent pruritic rash on her abdomen. Most likely diagnosis would be
- A.
  
  Scabies
- B.
  
  Pityriasis versicolor
- C.
  
  Atopic Dermatitis
- D.
  
  Contact Dermatitis
- E.
  
  Psoriasis
15.

On examination of a patient you observe the rash shown in the image. You would describe this rash as
- A.
  
  Macular
- B.
  
  Petechial
- C.
  
  Papular
- D.
  
  Lichenification
16.

A 19 year old female college freshman presents to your office for a physical exam. On ROS she admits to intermittent vaginal itching and white discharge. She is not sexually active. She is adopted and does not know any of her family medical history. In addition to a curdly white discharge present on vulvar inspection, you note the following on physical examination: BMI 32.2. You order a wet prep microscopic examination of her vaginal discharge. Of the following, what is the most appropriate next step?
- A.
  
  Order a serum cortisol
- B.
  
  Order a lipid profile
- C.
  
  Order a fasting insulin level
- D.
  
  Order a fasting blood glucose and oral glucose tolerance test
- E.
  
  Order a GC/Chlamydia PCR
17.

Your patient presents with intense pain around the wound, subsequent to amputation of the left leg following a farming accident. He is febrile and incoherent. The wound is bronze-colored and displays crepitus on palpation. A sample of exudate submitted for anaerobic culture grew the organism seen in the Gram stain image below. What is the most likely causative agent?
- A.
  
  Corynebacterium diphtheria
- B.
  
  Clostridium perfringens
- C.
  
  Staphylococcus aureus
- D.
  
  Clostridium tetani
- E.
  
  Bacillus cereus
18.

Your patient is a 52-y-o patient who has just noticed a callous on her foot. The patient is diabetic with poor glycemic control, a BMI of 32, and is a lifelong smoker. Upon examination, you note that the foot is swollen, the skin has been broken, and there is a purulent wound. There is insensitivity to the Semmes-Weinstein 5.07 (10 g) monofilament. Analysis of the major pathogen in the wound of this patient reveals a Gram-positive, catalase-positive, and coagulase-positive coccus which is strongly -hemolytic. What is this pathogen?
- A.
  
  Streptococcus pyogenes
- B.
  
  Staphylococcus aureus
- C.
  
  Staphylococcus epidermidis
- D.
  
  Enterococcus faecalis
19.

A 35-year-old man suffered a 3^rd degree electrical burn to his left arm. One week later, while being prepared for a skin graft, some burned areas began to exude blue-green pus with a fruity odor. What would you expect to grow?
- A.
  
  A Gram-negative, oxidase-positive rod
- B.
  
  A Gram-positive, catalase-positive coccus in clumps
- C.
  
  An anaerobic spore-forming Gram-positive rod
- D.
  
  A Gram-negative, oxidase-negative rod
20.

A pathogen considered a prime candidate for germ warfare (i.e., bioterrorism) is a very small, encapsulated, Gram-negative coccobacillus that grows slowly on chocolate agar. Infection can be via a number of routes, including inhalation, direct contact, and ingestion. In the U.S., people who come into contact with infected rabbits are at risk. Which pathogen is this?
- A.
  
  Francisella tularensis
- B.
  
  Bacillus anthracis
- C.
  
  Brucella abortus
- D.
  
  Pasteurella multocida