SKIN PATHOLOGY-2

Question 1

Describe the morphologic finding shown

Deborah Dalmeida MD

Answer 1

Bowl-shaped lesion with a central depression filled with keratin

The areas of central depression contain viral particles- eosinophilic inclusion bodies known as molluscum bodies or Henderson Patterson bodies.

Deborah Dalmeida MD

Question 2

Identify the lesion and causative agent

Superficial skin infection; usually face

vesicles and pustules that rupture to form varnish colored

lesions

Deborah Dalmeida MD

Answer 2

Impetigo

S. aureus

Deborah Dalmeida MD

Question 3

Identify the causative agent

Adult forms infect the skin over the body

breed in clothing

Papular rash, intense itching

Deborah Dalmeida MD

Answer 3

Pediculus humanus corporis (body louse)

Deborah Dalmeida MD

Question 4

Tuberculoid/Lepromatous leprosy?

Negative lepromin skin test

Absence of granulomas

Numerous acid-fast bacteria within foamy macrophages (MPs)

Deborah Dalmeida MD

Answer 4

Lepromatous leprosy

Deborah Dalmeida MD

Question 5

Identify the infection and infective agent

Fungal infection of the hairy regions with skin rich in sebaceous glands

Scaly, yellowish, greasy dermatitis

Deborah Dalmeida MD

Answer 5

Seborrheic dermatitis - Malasezzia

Deborah Dalmeida MD

Question 6

Identify the infection and causative agent

Superfical dermatophytic infection involving body surface

Annular, elevated red, scaly border and clear centers

Deborah Dalmeida MD

Answer 6

Tine corporis - Trichophyton rubrum

Deborah Dalmeida MD

Question 7

List the toxins involved

Febrile, superficial blistering disease

Deborah Dalmeida MD

Answer 7

exfoliative toxins A and B derived from S. aureus

Deborah Dalmeida MD

Question 8

Identify the infection

Superficial dermatophytic infection of the groin

Excessive sweating

Non-annular, elevated, scaly border

Deborah Dalmeida MD

Answer 8

Tinea cruris

Deborah Dalmeida MD

Question 9

Identify the lesion and causative agent

Verrucous papular lesions that are covered by scales

MC sites: fingers, soles

Answer 9

Verucca vulgaris

Human Papilloma virus

Question 10

Tuberculoid/Lepromatous leprosy ?

Positive lepromin skin test

Hypopigmented macular lesions with complete sensory loss

Granulomas are present, very few acid fast bacilli

Answer 10

Tuberculoid

Question 11

2 conditions assoc with seborrheic dermatitis

Answer 11

Parkinson disease

AIDS/AIDS-related complex

Question 12

Type of cellulitis involving the superficial layers of the epidermis and cutaneous lymphatics

Answer 12

Erysipelas

Streptococcus pyogenes

Question 13

Identify the lesion and causative agent

Superficial skin infection; usually face

dry, honey-colored, crusted (S. pyogenes) lesions

Answer 13

Impetigo

Streptococcus pyogenes

Question 14

Identify the infection and causative agent

Superficial dermatophytic infection of the scalp

Infects outer hair shaft

+ve Wood lamp

Answer 14

Tinea capitis- Microsporum

Question 15

Identify the lesion and enunciate the etiology

Prodrome of radicular pain and itching

Rash follows sensory dermatomes

Answer 15

Herpes zoster (shingles)

reactivation of VZV

Question 16

Identify the causative agent

Adult

Intensely pruritic erosions and burrows in web spaces between fingers, intertriginous areas

Answer 16

Sarcoptes scabiei var. hominis

Question 17

1. Identify the infection

Tissue protozoa

locates in macrophages/ dendritic cells

Bite–>Papule → ulcers with raised borders

2. What’s the vector?

Answer 17

1. Cutaneous leishmaniasis
2. Phlebotomus

Question 18

Identify the lesion and enunciate the mechanism of infection

Painful, pustular lesion

Commonly occurs in dentists

Answer 18

Traumatic implantation of the virus

Question 19

Identify the infection and causative agent

Superficial dermatophytic infection of the skin

Predominantly affects Upper trunk, extremities; penile shaft

Hypo and hyper pigmented patches

KOH prep shows findings as seen in the attached image

Answer 19

Pityriasis rosea (aka tine versicolor)

Causative agent: Malasezzia globose

Question 20

Identify the causative agent

Scalp infection

Intense itching

Adult forms of the causative agent lay eggs (nits) on hair shafts

Answer 20

Pediculus humanus capitis (head louse)

Question 21

Identify the lesion and causative agent

Multiple papules with beginning central umbilication

commonly occurs in children; can be sexually transmitted in adults (common in AIDS)

Answer 21

Molluscum contagiosum

Pox virus

Question 22

Identify the lesion and causative agent

Fungal infection that presents as an Erythematous rash that occurs in body folds

KOH preparation: pseudohyphae and yeast

Answer 22

Intertrigo

Question 23

Identify the infection and causative agent

Superficial dermatophytic infection of the scalp

Infects inner hair shaft

−ve Wood lamp

Answer 23

Tinea capitis - Trichophyton tonsurans

Question 24

Identify the causative agent

Adult forms of this agent live in the pubic hairs

Answer 24

Pthirus pubis (pubic louse, crabs)

Question 25

**Identify the causative agent** Feeds on human blood Pruritic red papules/wheals occur as an allergic reaction to the anesthetic in the saliva of the organism

Answer 25

Bedbug - Cimex lectularius

Question 26

Subcutaneous infection in humans who come in contact with infective larvae of the dog or cat hookworms

Answer 26

Cutaneous larva migrans

Question 27

Describe the Tzanck smear finding in Herpes lesions (Varicella Zoster,gingivostomatitis, herpetic whitlow etc)

Answer 27

multinucleated (MN) squamous cells (SCs) with eosinophilic intranuclear (IN) inclusions, ground glass appearance

Question 28

**Identify the infection and causative agent** Superficial dermatophytic infection MC in a person with sweaty feet Macerated scaling rash between one or more toes

Answer 28

Tine pedis- trichophyton rubrum

Question 29

**Identify the lesion and causative agent** ## Footnote Acute inflammation of subcutaneous (SC) connective tissue

Answer 29

Cellulitis S. aureus