Brainscape's Knowledge GenomeTM


Top Flashcards (Certified)
All Flashcards

SPM- Dermatology > Common Skin Infections > Flashcards

Common Skin Infections Flashcards

(118 cards)

Start Studying
1
Q

What is cellulitis?

A

A common bacterial infection of the deep subcutaneous tissue.

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

Describe the symptoms of cellulitis?

A

Red skin
Painful
Hot to the touch
Swelling
Can develop blisters, erosions and ulcerations
Systemic symptoms due to infection- fever, malaise, tachycardia, fatigue, rigors

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

What is erysipelas?

A

Erysipelas is an infection of the superficial layers of the skin, cellulitis is an infection of the lower dermis and upper subcutaneous tissue. They;re often considered together due to similar features.

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

What conditions make an individual more prone to cellulitis?

A 
Previous episodes of skin disease
Cuts in the skin
Insect bites
IVDU
Alcohol excess
Swollen limbs due to- Nephrotic syndrome, RHF, lymphoedema, venous insufficiency, CKD
Liver disease
Obesity
Poorly controlled diabetes (hyperglycaemia feeds infection and there is reduced tissue repair)
Immunosuppression
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What are the most common causes of cellulitis?

A 
Streptococcus pyogenes (2/3 of cases)
Staph aureus (1/3 of cases)
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

Describe the appearance of cellulitis?

A

Most commonly see in the lower limbs but any area of skin can be affected, not it is most often unilateral. If bilateral other causes should be considered.
Redness
Swelling
Increased temperature
Pain
Edge is shart in erysipelas and ill-defined in cellulitis
Area of redness spreads, ascends from the lower leg

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

How does the border of redness differ with cellulitis and erysipelas?

A

Erysipelas- the border is sharp and raised

Cellulitis- the border is less well defined

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

How are cellulitis and erysipelas diagnosed?

A

History and clinical examination

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What are some complications of cellulitis?

A

Septicaemia- do blood cultures and monitor closely
Necrotising fasciitis- if infection spreads in the fascial planes- severe pain that is worse than expected, skin pallor, loss of sensation and necrosis.
Spreading infection
Endocarditis
Abscess formation

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

Where does commonly erysipelas affect?

A

Legs

Less commonly the face- infection of the face can increase the risk of meningitis.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

How is cellulitis or erysipelas diagnosed?

A

History and Examination
Bloods- FBC, ESR, CRP, U&Es, Culture (risk of septicaemia)
CXR- Risk of pneumonia
Doppler ultrasound- if suspecting DVT or peripheral vascular disease

Note- If suspecting complication of necrotizing fasciitis and MRI should be done.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the management for cellulitis or erysipelas?

A

Swelling and redness should be marked to monitor spread

Oral antibiotics for uncomplicated case e.g. flucloxacillin, amoxicillin.

IV Antibiotics for severe cases and systemic upset. Include fluid and oxygen if required. Minor for sepsis. Follow local guidelines for ABx therapy.

Supportive Therapy- Raise leg, IV fluids (depends on cause), monitor temperature, analgesia…

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

What is impetiogo?

A

Impetigo is a skin infection that is most often caused by staph aureus but may less commonly be caused by strep

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Which age group is impetigo most common in?

A

Young children and infant

But can affect adults if they are immunosuppressed

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What skin conditions increase an individuals risk of developing impetigo?

A

Atopic dermatitis/eczema
Scabies

Due to breaks in the skin which reduce barrier immunity and so can result in secondary bacterial infection.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

Describe the features of impetigo?

A

Initially small pustules
These tend to break away easily and this results in the formation of patches with yellow crusts
These are small at first but can increase in size.

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

How can impetigo be spread?

A

Through scratching of lesions it can be spread around the body, it is therefore advised to avoid touching the lesions and to wash hands afterwards if you do accidentally touch them.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What is the name given for impetigo that causes blisters to form?

A

This is bullous impetigo- there are small vesicles that evolve into flaccid transparent bullae.

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

What are associated symptoms of impetigo?

A

Lymphadenopathy
Mild fever
Malaise

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some complications that can occur from impetigo?

A

Staphylococcal scalded skin syndrome
Cellulitis
Septicaemia
If Strep- Post Streptococcal glomerulonephritis, Rheumatic fever

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

How is impetigo diagnosed?

A

It is normally diagnosed clinically based on the appearance and features.

Swabs may be taken for MC+S
Bloods- FBC, Culture (if could be septic and systemically unwell)

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

What is the treatment for impetigo?

A

Clean the plaque/crusts with water to gently remove the crusts

Antibiotic creams such as fusidic acid/mupirocin, less commonly used due to emerging resistance. Antiseptic washes may be used e.g. chlorhexidine, povidone iodine

Oral antibiotics e.g. flucloxacillin/erythromycin if severe/systemically unwell (fever/malaise)

Avice careful hand hygiene, wash hands after applying creams, don’t touch lesions if possible, avoid sharing towels, flannels, clothes, wash these after use at high temperature with laundry bleach.

Wash and change clothing and bedding daily during first few days.

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

How long should children spend off school after impetigo?

A

At least 48 hours after starting oral Abx

Or when the crusts have dried up

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

What is scabies?

A

Scabies is an intensely itchy rash that is caused by a parasite mite that lives on the skin surface

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
How is scabies spread?
Through skin to skin contact- rarely through sharing towels, clothes, bedding
26
Where are people at risk of catching scabies?
``` Densely populated areas Poverty areas Institutionalised care e.g. in prisons and care homes Refugee camps Selly oak Immunosuppressed people ```
27
What are scabies burrows?
Scabies burrows are created after mating between the scabies parasites. They male dies and the female burrows into the skin to lay the eggs. They can be seen as raised grey or reddish lines on the surface of the skin extending red areas. They are found in the web-spaces between fingers, on the palms, wrists, elbows, nipple, armpits, buttocks, penis and heels.
28
What are the features of a scabies manifestation?
Very intense itching with is more severe at night and often disturbs sleep Scabies rash- papules, vesicles, pustules, erythema and nodules affecting the finger webs, wrist flexures, axillae, abdomen, buttocks and groin Excoriations and Eczematised
29
What is crusted scabies?
This is also called Norwegian scabies. It occurs when there are thousands of mites colonising a person. It is highly contagious. It is seen in the elderly or immunosuppressed
30
How does crusted scabies present?
Generalised itchy scaly rash- often misdiagnosed as psoriasis or seborrheic dermatitis Scaling if often more prominent in the finger webs, on wrists, elbows, breasts and scrotum Itch may be absent or minimal Can affect the scalp
31
How is scabies diagnosed?
History and examination features Ask about other people in the house being affected Dermatoscopy may show the mites Microscopy may show the mites, eggs or feces
32
What is the treatment for scabies?
Scabicides- these are insecticides 5% Permethrin cream applied to all of the skin below the neck for 12 hours. Malathion liquid is an alternative. Two treatments are required one week apart as eggs can hatch. Alternatively, for severe scabies or if institution oral Ivermectin may be used. All clothes, bed sheets, towel should be washed at a high temperature.
33
What is folliculitis?
Inflammation of the hair follicles
34
What can cause folliculitis?
Infection- Bacterial (most often staph), yeats, fungi, viral (HSV, Herpes Zoster) Irritation due to ingrown hairs- -After shaving, waxing. Any swabs taken will be sterile. Occlusion- -After use of emollients, moisturisers Overuse of topical steroids Inflammatory skin conditions Acne vulgaris and rosacea are forms of folliculitis
35
Describe the features of folliculitis
Tender red spots often with surface pustules Can affect the hair on any of the body surfaces Folliculitis Barbae affects the beard area.
36
How is bacterial folliculitis treated?
Antiseptic creams Antibiotics creams If chronic- mild steroid creams may reduce inflammation and can be given in addition to the steroid creams. Oral antibiotics
37
How might the cause of folliculitis be investigated?
Close inspections | Swabs taken from the site or any pus from the pustules may be used for MC and S, PCR...
38
What can cause folliculitis?
Infection Occlusion Irritation (e.g from shaving- pseudofolliculitis) Various skin disease
39
Which yeast infection has been found to cause folliculitis? What is the treatment?
Malassezia Treatment is topical or oral anti-fungals E.g. clotrimazole, econazole, fluconazole
40
What is pseudofolliculitis?
This is due to ingrown hairs, which can be seen with a microscope. Can occur with shaving, waxing or plucking. Any swabs taken from the site will be sterile.
41
Where can re-infection commonly come from for folliculitis affecting the beard area? (Folliculitis barbae)
This can come from the nose and no nasal anti-biotic ointments may be given that can be applied to the inside of both nostrils
42
What is the name for fungal infections which affect the scalp?
Tinea capitis- usually result in scaling and hair loss but can sometimes cause folliculitis.
43
Which virus causes viral warts?
Human papilloma virus causes viral warts (this also causes verrucas) There are over 100 types of HIV causing papillomas/warts/cancers
44
Which patients are prone to developing warts?
Immunosuppressed patients- this includes patients with HIV and those taking immunosuppression.
45
What process causes the development of a wart?
Keratinocyte proliferation- hyperkeratotic so have a hard surface
46
How is HPV spread?
Direct skin to skin contact (this is also how it spreads from one area of the body to another) Sexually transmitted too.
47
What is a dangerous risk of HPV?
Some strains are oncogenic and increase the risk of cervical, anal, penile and vulval cancer.
48
What are the treatment options for warts?
People may choose to leave it alone and it may go away on it's own. But if unsightly, painful or embarrassing options include: Topical Treatment - Salicylic acid (wart paints) - Cryotherapy - Podophyllin Surgery- - Curettage and cautery
49
What is the difference between varicella zoster virus and herpes zoster?
Varicella zoster causes chicken pox | Herpes zoster causes shingles and occurs after re-activation of VZV.
50
Describe the features of herpes zoster
Localised Blisters Painful Erythematous Rash Confined to dermatomal patterns of one or two sensory nerves Fever, Headache, Lymphadenopathy Pustules and crusting from ruptured blisters can also occur Note- Pain is often the first symptom
51
What is the treatment for herpes zoster virus?
Antiviral therapy- Aciclovir Analgesia Rest Preventive secondary infection- Emollients Oral ABx If there is any eye involvement an opthamologist should be involved urgently. A sign that may predict this is Hutchinson's sign which is involvement of the nasociliary nerve- shown by vesicles/blisters/lesions/crusting on the side of the nose.
52
Who is more likely to develop shingles (herpes zoster)?
Elderly Immunosuppressed Psychological or emotional stress
53
How can shingles be diagnosed?
History and examination Swabs may be taken from the blisters that can be sent for viral culture/PCR
54
Why might someone with herpes zoster develop facial weakness on one side?
Occasionally muscle weakness can be a complication of shingles. If the facial nerve is involved it is called Ramsey-Hunt Syndrome.
55
What is tinea?
Tine refers to a skin infection with a dermatophyte (ring work) fungus. It is given a specific name depending upon where it affects in the body.
56
What are dermatophytes?
Dermatophytes are a group of fungi which can infect the skin, hair and nials- causing tinea.
57
Where does tinea barbae affect?
The beard area
58
Describe the appearance of tinea barbae?
Most often affects farmers as it comes from animal fungi, so people come into contact with an infected animal Red lumpy areas, pustules and cursing around hairs. It is not painful or itchy.
59
Where does tinea capitis affect?
The scalp- it is a fungal/dermatopyhte infection
60
What age group does tinea capitis most often affect?
Children- between three and seven years of age, less frequently seen in adults.
61
Describe the appearance of tinea capitis
``` Dry scaling Black dots- where hairs are broken off at scalp surface Smooth areas of hair loss Favus- yellow crusts and matted hair. Lymphadenopathy may be associated ```
62
How is tinea diagnosed?
Take scrapings (from the edges of the lesions which are more active), scalp brushings or nail clippings for microscopy and culture.
63
How is tinea capitis treated? give an example of one agent
This requires systemic treatment with oral antifungal agents. Oral griseofulvin or terbinafine may be used.
64
Where does tinea corporis affect?
The trunk, legs or arms with a dermatophyte fungus
65
Describe the features of tinea corporis?
Patch erythematous lesion Anular- appearing ring like or circular Clearly defined raised scaly edge is typical
66
What is the treatment for tinea corporis?
Topical antifungal agents- e.g. Terbinafine or imidazole creams If these fail oral agents can be used e.g. Terbinafine, Griseofulvin
67
How is tinea diagnosed?
Skin scrapings may be taken which are sent for microscopy and culture. These should be taken from the scaly edge of lesions as they are more active sites.
68
Where does tinea cruris affect?
This is tinea affecting the groin, it is a dermatophyte infection
69
Who does tinea cruris most commonly affect?
Adult men- it is known as the jock itch
70
Describe the appearance of tinea cruris?
``` Affecting the groin Erythematous red patches Scaling at the edge Well demarcated border Itching Annular lesions- ring like or circular ```
71
What is the treatment for tinea cruris?
Topical antifungals such as Terbinafine or Imidazole (applied twice daily for at least two weeks) and oral if these fail Oral agents include Terbinafine, Griseofulvin.
72
Where does tinea faciei affect?
The face, but not the beard and mustache areas
73
Where does tinea pedis affect?
The feet, it's also called athlete's foot.
74
What are some risk factors for contracting tinea pedis?
Direct contact with the organism- walking barefoot in changing rooms, sharing towels Excessive sweating Occlusive footwear- e.g heavy industrial boots Immunodeficiency or diabetes or immunosuppression
75
What are the features of tinea pedis?
``` Tends to be symmetrical and unilateral Itchy erosions and scales between toes Erythema Scaling covering the sole and side of the feet Erythema ```
76
When someone presents with tinea of any site what should be done?
Examination of all other potential sites that could develop tinea infection
77
What are some differentials for tines?
Eczema/Dermatitis Irritant or allergic contact dermatitis- e.g. from socks, Psoriasis If feet- palmar plantar pustulosis These are more likely to be bilateral and symmetrical unlike tinea which is often unilateral
78
What is the management of tinea pedis? | Include general measures.
General measures- keep the feet dry, dry between toes, don't wear sweaty socks, reduce wear of occlusive footwear Topical Antifungal therapy- Azoles e.g. Imidazole If failure oral antifungals may be used e.g. Fluconazole, Griseofulvin
79
How can tinea pedis be prevented?
Dry feet and toes after washing Use drying foot powder e.g. Talc Avoid wearing occlusive footwear for long periods Change socks Don't put sweaty socks back on Dry shoes and boots Clean shower and bathroom floors using bleach.
80
What is candidiasis?
This is a type of fungal infection that is caused by yeast overgrowth
81
Who is more prone to developing candidiasis?
Immunosuppressed people- Oral candidiasis may be a sign of HIV.
82
What is the most common candidiasis causing organism?
C.albicans
83
What are features of a candida infection?
Erythema May have itching White plaques (pseudo-membrane) Erythematous candidiasis causes redness and itching.
84
Where do candida infections typically affect?
Mouth- Note the white scapes off unlike Lichen Planus Oesophagus Nappy Area- Causing nappy rash (redness with satellite regions) Vulvovaginitis- cottage cheese discharge, painful urination
85
Where does candida infection of the skin commonly manifest?
Vagina Glans of penis Skin folds Web areas
86
How might candida be diagnosed?
Swabs or scrapings can be sent for microscopy and culture
87
What agents can cause angular stomatitis?
Candida Staph HSV Swabs should be taken for MC+S, PCR if suspecting HSV
88
What is candidal intertrigo?
This is candida affecting the skin folds It causes an erythematous scaly plaques/patches within the skin folds that. Associated with satellite lesions- papules or pustules.
89
What is the most common causative organism of nappy rash?
It is mostly a form of contact dermatitis due to the urine and faeces staying in the nappy too long and irritating the skin, also mechanical friction with the nappy. It's called Napkin Dermatitis. Candida albicans
90
What are some general measures for nappy rash?
Keep the area dry Use barrier creams such as emollients and sudocrem Clean the baby soon after soiling Wipe gently with water soaked cloth (rather than baby wipes as the preservatives can be irritating) Allow to air dry Allow diaper free times Topical weak steroids may be used for flares Anti-fungal creams is suspicious of C.albicans as a cause
91
What is onychomycosis?
This is a fungal nail infection, can be causes by dermatophytes or candida. If caused by tinea it is called tinea unguium.
92
Describe some of the features of onychomycosis?
``` Yellowing or whitening of the nail Distal onycholysis Spread to other nails Destruction of the nail Tender nail bed ```
93
How is the diagnosis of onychomycosis made?
Nail clippings can be taken which are then sent for microscopy and culture. Some of the discolored areas may be scraped off.
94
What is the treatment for onychomycosis?
Topical antifungals at first e.g. Terbinafine cream Then oral antifungals if treatment failure e.g. Itraconazole
95
What is pityriasis versicolor? What are its features?
A fungal infection which affects the trunk. It typically causes hypopigmented patches (but also can be pink or brown) Scaling is common May have itching
96
What is the causative organism of pityriasis versicolor?
Malassezia furfur- there us overgrowth of this organisms. They produce azelaic acid which inhibits melanin production leading to hypopigmentation and prevention of affected skin from tanning.
97
What is the treatment for pityriasis versicolor?
Topical antifungals such as imidazole cream. Sometimes oral agents are used such as itraconazole or fluconazole
98
What is erythema multiforme?
A hypersensitivity reaction most commonly triggered by infections- there are major and minor forms. It is a type IV hypersensitivity reaction.
99
What are the features of erythema multiforme?
Target lesions Initially seen on the back of the hands/feet before spreading to the torso Upper limbs are more commonly affected than lower limbs Pruritus is occasionally seen and is usually mild
100
What is the most common cause of erythema multiforme?
HSV infection Mycoplasma infections and cause Erythema multiforme.
101
What drugs can cause erythema multiforme?
``` Penicillins Sulphonamides Carbamazepine Allopurinol NSAIDs OCP ```
102
What are the features of erythema multiforme major?
There is mucosal involvement as well as skin. Causes irregular painful ulcers to develop. Hemorrhagic crusting is seen around the lips.
103
What causes processes underpin acne vulgaris?
``` Basal keratinocyte proliferation Increased sebum production Colonisation by Propionibacterium acnes Inflammation Comedones (white and black heads) blocking secretions leading the papules, pustules, cysts) ```
104
Describe the features of acne vulgaris?
``` Open and closed comedones Pustules Nodules Cysts Scarring due to inflammatory processes Common sites affected include the face, neck, upper shoulders ```
105
What are the treatment options for acne?
Topical Therapies: Topical Benzoyl Peroxide or Topical Retinoid (avoid antibiotics). Topical antibiotic may be combined with benzoyl peroxide Oral Antibiotics- Doxycycline, Lymecycline,, Erythromycin if pregnant or less than 12 Oral Retinoids- Isotretinoin under specialist prescribing. Women must be on contraceptive as it is teratogenic.
106
What are some complications of acne?
Scaring Skin deformity Psychological effects- e.g. reduced self-esteem Social isolation
107
What is acne rosacea?
A chronic skin disease of unknown ing cause that causes redness of the face. Flushing is often the first features.
108
What are the features of acne rosacea?
Facial flushing is often the first symptom Typically affects the nose, cheeks and forehead Telangiectasia are common Rhinophyma- nose enlarges due to soft tissue overgrowth Papules and pustules Blepharitis and conjunctivitis is ocular rosacea
109
What is the treatment for acne rosacea?
Mild- Topical metronidazole More severe disease- oral tetracycline, doxycycline. Reduces papules and pustules but no effect on redness Lasers can be used for telangiectasia Camouflage creams for redness. Advice to wear high factor sun cream.
110
What is molluscum contagiosum?
This is a skin infection caused by molluscum contagiosum virus (MSV)
111
How is mollucscum contagiosum virus commonly spread?
Skin to skin contact and sharing of towels flannels
112
Who does molluscum contagiosum commonly affect?
Children aged 1-4 but an affect other age groups
113
What are the features of molluscum contagiosum?
Small pinkish or pearly white papules with central umbilication Upto 5mm in diameter Lesions appear in clusters Common sites include the trunk and flexures.
114
How is molluscum contagiosum often spread in adults? Where does this tend to cause lesions to develop?
Sexual contact Lower abdomen, pubic area, thighs, genitalia
115
What is the treatment for molluscum contagiosum?
Generally not required as it resolves itself normally within 18 months. Explain that lesions are contagious so avoid sharing towels and flannels. Treatment may be considered if lesions are troublesome: - Cryotherapy - Pinching or piercing the lesions to induce minor trauma - If eczema develops around lesions- topical emollients and corticosteroids - If secondary infection develops topical (e.g. fusidic acid) or oral ABx may be required.
116
How does lichen sclerosus commonly present?
Inflammatory condition which affects the genitalia and is more common in elderly women Itch is a prominent features White plaques form
117
What is the management for lichen sclerosus?
Topical steroids and emollients Skin biopsy may be done is there is a failure to respond to treatment or suspicion of malignancy.
118
What is a risk factor of lichen sclerosus?
Increased risk of vulval cancer

SPM- Dermatology (10 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions