Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

MBBS 4 Dermatology > Viral Infections > Flashcards

Viral Infections Flashcards

You may prefer our related Brainscape-certified flashcards:
Dermatology Board Prep flashcards
1
Q

What are warts?

A

Benign infections of the skin & mucous membranes caused by HPV

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Epidemiology of warts?

A
  • Cutaneous warts common in children and young adults, incidence reduces with age.
  • In children genital lesions may result from autoinnoculation from cutaneous lesions
    > should raise suspicion of sexual abuse when extensive.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Transmission of infection of warts?

A
  1. Genital infection
    - by intimate contact with affected individuals.
  2. Non-genital (skin) infection
    - Directly: person to person contact
    - Indirectly: contaminated surfaces/objects; swimming pools, gyms etc.
    Note: Individuals with sub-clinical infection can transmit the virus.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Clinical features of warts and what they depend on?

A

depend on HPV type and anatomic site of infection.
1. cutaneous lesions: HPV 1,2,3,4 and 10
2. mucosal lesions: HPV 6 and 11

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

Clinical classification of cutaneous warts?

A
  1. Common warts (veruccae vulgaris)
  2. Palmar-plantar warts
  3. Flats warts
  4. Filiform/digitate warts
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

Describe the appearance of common warts?

A

appear singly or grouped as rounded papules or nodules with rough, grayish scaly surface.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Location of common warts?

A
  1. common on sites prone to trauma but may locate anywhere
    - fingers, dorsal surfaces of the hands, knees, elbows
  2. Can also involve the nail
    - around nail plate: periungual
    - under nail plate: subungual
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Common causes of common warts?

A

HPV 1,2,4, 27, 57, 53

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Describe palmar and plantar warts?

A
  • Thick, endophytic, hyperkeratotic papules on the palms, soles and lateral surfaces of hands and feet
  • have gently sloping sides with central depression (hence myrmecia [antihill] warts)
  • Mosaic warts: coalescence into plaque of superficial plantar warts
  • May be extensive & painful when walking due to deep ingrowth
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Common causes of palmar and plantar warts?

A

HPV 1,2,4,27 and 57

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe filiform/figitate warts?

A
  • Located on the beard area, periorally, alae nasi and around the eyes.
  • Manifest as several skin coloured finger-like projections emanating from a narrow base.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe flat warts?

A
  • 1 to 4 mm slightly elevated, flat topped papules with minimal scale.
  • Commonly located on the hands, arms or face often in a linear array – demonstrating Koebner phenomenon.
  • Can be quite resistant to treatment, especially in HIV immune suppresion
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Flat warts causes?

A

HPV 3, 10, 28 and 41

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What is epidermodysplasia verucciformis?

A
  • Autosomal recessive inheritance with unique susceptibility to HPV 5 and 8.
  • Starting from childhood, widespread flat or minimally scaly lesions resembling P.versicolor
  • Always recur after treatment.
  • May transform to SCC in sun-exposed areas
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Principles of treatment of viral warts?

A
  • No single effective treatment
  • Some patients may chose to leave their lesions for spontaneous resolution.
  • Decision to treat should be based on individual basis
  • Where treatment is opted, aim should be to cure, but control of spread and relief of symptoms may be acceptable.
  • Paring the wart where possible to enhance effect of drug.
  • If drug used for 6 months without change, consider next level
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

First line therapy treatment for warts?

A
  1. Salicylic acid generally reserve concentration of more than 15 % to plantar and palmar surfaces
  2. Glutaldehyde 10 % solution or gel 2x daily
  3. Silver nitrate stick
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Second line therapy for warts?

A

Cryotherapy (avoid its use in peri and subungual)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Third line therapy for warts?

A
  1. Immiquimoid
  2. 5 fluoro uracil
  3. contact sensitisers
  4. cimetidine
  5. levimazole
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Surgical treatment of warts?

A
  1. currettage
  2. excision
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What is molluscum contagiosum?

A
  • Benign, usually self limiting disease in children (1-5 yrs),
  • Rare in adults, but may be present in genital area where it may be transmitted sexually
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

Cause of molluscum contagiosum?

A
  • Cause: pox virus
  • Incubation period: 2- 8 weeks
  • Transmission: person to person, autoinnoculation
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Clinical features of molluscum contagiosum?

A

Presents with discrete dome shaped papules with a umbilicated center from which a cheesy plug can be expressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Common sites of infection for molluscum contagiosum?

A

face, eyelids, neck axillae, thighs, genital regions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

What is eczema molluscum?

A

eczema and erythematous changes around lesions

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Management of molluscum contagiosum?

A
  1. Watchful waiting (in the immunocompetent)
    - since they are generally benign and self limiting.
  2. Treatment:
    - Curettage
    - Cryotherapy
    - Immiquimoid cream (Aldara)
25
Q

What is pityriasis rosea?

A
  • Common, acute, self-limited eruption that is believed to be caused by HHV7 or HHV6.
  • Generally asymptomatic, and spontaneously resolves in 2 – 10 wks
26
Q

Clinical features of pityriasis rosea?

A
  1. Some patients have flu-like symptoms; fever, tiredness, general malaise, arthralgia.
  2. Classically, one truncal, ‘herald’ or ‘mother’ patch preceeds other lesions by several days to weeks in 50-90 % of patients.
    - Is rounder, redder & scalier than the 2ndry patches
  3. Subsequent lesions form in crops, are smaller and align along cleavage lines at the back
    ‘christmas tree’ pattern
27
Q

Ddx for pityriasis rosea?

A
  1. Always rule out secondary syphilis
  2. T. Corporis
  3. Guttate psoriasis
  4. Drug reaction
28
Q

Treatment of pityriasis rosea?

A
  1. Generally none required
    - Reasurance and patient education
  2. Topical steroids if itch.
29
Q

What is chicken pox?

A
  • Highly contagious disease caused by primary infection with VZV
  • in temperate regions, largely affects children <10; in tropics: teenagers
  • transmission is by direct contact with lesions of CP or HZ persons or by respiratory route. (IP 15 dys)
  • Patients infectious 4 days before and 5 days after appearance of rash i.e until all lesions have crusted
    Note: Lifelong immunity follows infection, unless in immunosuppression
30
Q

Clinical features of chicken pox?

A
  1. Characterized by clear vesicles on erythematous base (‘dew drops on a rose petal’) on scalp, face, mouth and trunk
  2. Begin as red macules that rapidly (within 24 hrs) develop into papules, vesicles & pustules,
    - later umbilicate & crust, to heal without scarring (unless infected)
    - often new lesions arise for 4 dys, crusting by dy 6
31
Q

Key feature of chicken pox?

A

lesions in all stages of devpt in a given region of the body
i.e. erythema, papules, vesicles, pustules, crusts all at once!
- Commonly associated with prodrome: fever, malaise, arthralgia

32
Q

Complications of chicken pox?

A
  1. Pneumonia, myocarditis, encephalitis, meningitis esp in adults
  2. Reye’s syndrome: hepatitis and acute encephalopathy in children who receive aspirin for varicella symptoms
    - NO Aspirin in chicken Pox!!
33
Q

Management of chicken pox?

A
  1. Strict isolation
  2. Self limiting in children and decision to treat be made on case to case basis
    - Acyclovir 20mg/kg (max 800mg)5x daily for 5 days
    - AVOID aspirin for fever
  3. Rx recommended in adults and adolescents as have more severe course with more complications
    - Acyclovir 800mg 5x/dy for 5 days.
  4. More effective if given within 24 hrs.
  5. ALL immunosuppressed patients must be treated regardless of age and time of presentation.
34
Q

What is herpes zoster?

A
  • Characterised by painful, small grouped vesicles on an inflamed base.
  • Usually localised to a dermatome without crossing midline.
  • A result of reactivation of latent HHV 3 (VZV infection) from prior chicken pox.
  • Not as contagious as CP but possible to transmit CP in those previously not exposed
35
Q

Epidemiology of herpes zoster?

A

Incidence increases with age and immunosuppression
1. Below 45 yrs: annual incidence is 1/1000
2. Above 70 yrs: is 4x greater
3. HIV infected individuals: 30/1000/yr

36
Q

Most common affected dermatomes in herpes zoster?

A
  1. Thoracic (55 %)
  2. cranial (20 %, trigeminal the most common)
  3. lumbar (15 %)
  4. sacral (5 %)
37
Q

Clinical features of herpes zoster?

A
  1. usually preceded by prodrome of fever, headache & localised intense pain & parasthesia
  2. erythematous papules & plaques develop in the dermatome, which later form blisters.
  3. become pustular, crusted, and heal in 2 – 3 wks
    - May be longer in old age & and immunosuppression
  4. new lesions continue to appear for 1-5 days after first eruption.
38
Q

Describe the relationship between HIV and herpes zoster?

A
  • HZ one of earliest manifestations of HIV
  • Associated with mean CD4 of 400 μL-1
  • HZ found to have 70 % PPV for HIV in SS Africa
  • Greater severity of pain and longer duration than in the immunocompetent
39
Q

What is post-herpetic neuralgia?

A

localized pain persisting for at least three months after the acute inflammatory phase of acute zoster on the skin.
> 50% of adults >50yrs with HZ have PHN*

40
Q

3 typs of pain in post herpetic neuralgia?

A

The pain can be of three types
1. Triggered pain
- pain after normally non-painful stimuli eg touch, or
- mild pain stimulus causing massive pain sensation
2. Constant monotonous dull aching pain
3. Shooting, neuritic pain

41
Q

Cause of post herpetic neuralgia?

A
  • Believed to be due to persistent discharge & hyperexcitability of the nerves due to damage following the acute zoster.
  • Can therefore be prevented by early initiation of treatment for zoster.
42
Q

Complications of herpes zoster?

A
  1. opthalmic involvement
  2. motor involvement
  3. Ramsay Hunt syndrome
  4. disseminated HZ
43
Q

Opthalmic involvement in HZ?

A

In 76 % of cases, vesicles on the tip and side of the nose portend eye involvement (Hutchinson’s sign) vs 34 % without.

44
Q

Motor involvement in HZ?

A
  • S3 involvement: urinary hesitancy, retention
  • T6-sacral: bowel ostruction
45
Q

Ramsay Hunt syndrome in HZ?

A
  1. Facial paralysis
  2. herpes on external ear or eardrum
  3. auditory symptoms (tinnitus, vertigo, deafness etc)
46
Q

Disseminated HZ?

A
  • > 20 vesicles outside the affected dermatome.
  • Visceral involvement: lungs, CNS
47
Q

Management for HZ?

A
  1. Rule out HIV.
  2. For pain: NSAIDS, antidepressants
  3. Antibiotics for infected, crusted lesions.
48
Q

Treatment for HZ?

A

Preferably within first 72 hrs of rash
1. Acyclovir 800 mg 5x/dy for 7-10 days OR
2. Famciclovir 500mg 3x/dy) OR
3. Valacyclovir 1000mg 3x/dy
4. Consider IV treatment in: eye involvement, RHS, Disseminated HZ

49
Q

What are the herpes simples infections?

A
  1. HSV 1
    - Mostly affects oro-labial area
    - About 50 % of infected pple are asymptomatic
  2. HSV 2
    - Responsible for Genital area herpes
    - 20 % completely asymptomatic
    Note: Changes in sexual habits has seen each of the two viruses commonly infecting either site.
50
Q

Epidemiology of hepres simplex infections?

A

Common in HIV patients with low CD4 counts
- HSV should be considered for all ulcerative & nonhealing lesions anywhere on the body of HIV-infected persons.

51
Q

HSV is clinically classified as?

A

Since most initial infections are asymptomatic, clinical disease better classified as
1. First episode: either real primary infection or recurrent by clinically manifesting for 1st time
2. Recurrent episode: preceded by prior clinical eruptions

52
Q

Characteristic features of HSV infections?

A
  1. Infections are lifelong.
  2. Primary infection followed by viral axonal spread to nucleus from where continuous apperance to other sites occurs
  3. Lesions are very painful, self-limiting .
53
Q

Clinical features of oro-labial herpes?

A

Manifests as gingivostomatitis or herpes labialis.
- Acute Gingivostomatitis: broken vesicles that appear as erosions/ulcers covered with white membrane.
- Oral mucosa, tongue, tonsils, but may extend to involve pharynx.
- Untreated lasts for 1-2 weeks

54
Q

Clinical features of recurrent herpes labialis?

A

aka cold sore, fever blisters
- Recurrent HSV 1 responsible 95 % of the time.
- Typically present as grouped blisters on erythematous base ± lip swelling, later pustules & ulceration
- Lips common site, but any site possible; cheeks, eyelids, earlobes.
- Prodrome of tingling, itching or burning may ocur.
- headance, fever, nasal congestion not unusual.
- Sun exposure (UVB) frequent trigger.
- 2-3 recurrences/yrs

55
Q

What is herpes gladiatorum?

A

on the neck, side of the face and forehead of persons wrestling with infected individual.

56
Q

What is herpetic whitlow?

A
  • infection of fingers and periungual area.
  • begin as tender erythema on lateral nail fold or palm, b4 deep blisters aft 24-48 hrs.
57
Q

What is eczema herpeticum?

A
  • HSV 1 infection of skin of mostly Atopic Dermatitis pts.
  • also seborrhoeic dermatitis, pemphigus, Darier’s etc
  • small vesicles mostly within original dermatitis
  • soon enlarge, umbilicate , form pustules and crust
58
Q

Herpes in immunosuppression?

A
  • high risk of reactivation, hence more severe, more persistent and more recurrent episodes.
  • as a rule, any erosive mucocutaneous lesion should be considered herpes until otherwise proven
  • Lesions typically erosions or crusts; vesicles may be missed.
59
Q

Describe genital herpes?

A
  • Transmitted by skin-skin contact, usually during sex.
  • Many cases asymptomatic
  • viral shedding can take place in between symptomatic episodes.
  • even normal appearing skin can shed viral particles.
60
Q

Clinical features of genital herpes?

A
  • Typical grouped blisters on erythematous base
  • New such blisters continue to form over 7-14 dys (2-3 dys if recurrent episode)
  • Duration: 3 wks or more (primary episode), ~7dys (recurrent episode).
61
Q

Treatment for herpes simplex infections?

A
  1. acyclovir
  2. famciclovir
  3. valacyclovir

MBBS 4 Dermatology (21 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions