Download MBBS (Bachelor of Medicine and Bachelor of Surgery) Latest Skin Diseases Handbook Lecture PPT
Table of Contents
7. Gyrate Erythema
Erythema Chronicum Migrans (Lyme
1. Acne
Disease)
Rosacea
8. Pre-malignant and Malignant Les
2. Bacterial Infections
ions
Folliculitis
Actinic Keratoses
Impetigo
Basal Cell Carcinoma
Squamous Cell Carcinoma
3. Benign Neoplasms
Malignant Melanoma
Seborrheic Keratoses
Atypical Mole (Dysplastic)
Granuloma Pyogenicum
Atypical Mole
Lentigo Simplex
Atypical Mole
Atypical Mole
4. Childhood Infectious Disea
ses/skin Lesions
9. Psoriasis
Varicella (Chicken Pox)
Psoriasis of the Nails
Hand, Foot and Mouth Disease
Intertriginous Psoriasis
Verruca Plana
Psoriasis of the Scalp
Pustular Psoriasis
5. Eczematous Dermatitis
Guttate Psoriasis
Pityriasis Rosea
Vesicular Hand Dermatitis
10. Sexually Transmitted Diseases
Seborrheic Dermatitis
Herpes Simplex, Penis
Nummular Dermatitis
Herpes Simplex, Vulva
Herpes Simplex, Perineum
6. Fungal Infections
Herpes Simplex in AIDS
Tinea Capitis
Condyloma Acuminatum (Genital
Tinea Versicolor
Warts)
Candidiasis
Secondary Syphilis
11. Stings and Insect Bites
Scabies
Pediculosis (Lice)
12. Urticaria
Papular Urticaria
Urticaria
13. Viral Infections
Molluscum Contagiosum
Herpes Simplex
Herpes Zoster
Rosacea
Rosacea is a congestive blushing and
flushing reaction of the central areas of
the face. It is usually associated with an
acneiform component (papules,
pustules, and oily skin). It usually
occurs in middle-aged and older people.
The cheeks, nose, and chin, on the
entire face, may have a rosy hue.
Burning or stinging often accompanies
episodes of flushing. It is much more
common than lupus erythematosus, with which it is often confused. Rosacea
is distinguished from acne by age, the presence of the vascular component, and
the absence of comedones.
Folliculitis
Folliculitis is characterized by red-ringed
papules and pustules at hair follicles. Gram
negative folliculitis may be spread by
contaminated hot tubs. Gram stain and culture
will help to differentiate bacterial from non
bacterial folliculitis. History is important for
pinpointing the cause of non-bacterial
folliculitis.
Impetigo
Superficial honey-colored serous crusts are
characteristic of this disorder. It is usually
caused by a staphylococcus infection. Culture is
rarely reliable.
Seborrheic Keratoses
These lesions are benign overgrowths of
epithelium, largely appearing on the torso,
face, and neck. They are seen on almost every
one over the age of 50. The borders are
typically irregular, and they range in color
from beige or gray-white to very dark brown.
These "barnacles" of older skin can number
only a few to as many as hundreds. Although
often raised and dry, they can be flatter and
greasier (seborrheic) in texture.
Granuloma Pyogenicum
This is a vascular reactive nodule that develops as
a response to a minor injury. The overgrowth of
capillaries leads to a raised red lump which bleeds
profusely when torn.
Lentigo Simplex
These lesions occur on sun-exposed skin, especially
face, arms, and hands. Lesions are flat, and
pigmented in shades of brown, with characteristically
sharp borders. They tend to fade with sun avoidance.
Varicella
Chicken Pox
The rash is pruritic and most prominent on the face,
scalp and trunk. It appears as multitudes of red
ringed papules and vesicles in varying stages of
development. Crusts eventually form and slough off
in 7 to 14 days. Nondermatomal distribution and
lesions of varying stages distinguish primary
varicella from herpes zoster. Fever and malaise may be mild in children and
much more severe in adults.
Hand, Foot, and Mouth Disease
The disorder is characterized by stomatitis and
vesicular rash on palms of hands and soles of feet. It
is caused by Coxsackieviruses A5, 10, 16. The
development of mouth sores is most troublesome to
adults. The skin lesions are vesicopustules, 0.5 to 5
mm, red-ringed, more oval than round, on palms,
sides of fingers and soles.
Verruca Plana
The numerous discrete lesions, closely set, usually
occur on face, dorsa of hands and shins. Lesions are
flat-topped, slightly elevated, well demarcated,
generally flesh-colored, with a matte-smooth surface.
Lesions tend to spontaneously disappear.
Pityriasis Rosea
This disorder is a common, but unexplainable,
reaction. The initial lesion, "herald patch", is red and
scaly, followed in 1 to 2 weeks by widespread, oval,
scaling, fawn-colored macules 4 to 5 mm in
diameter over the trunk and proximal extremities.
Pityriasis rosea is usually an acute self-limiting
illness that lasts 4 to 8 weeks. It is not highly infectious.
Vesicular Hand Dermatitis
This disorder is a severely pruritic reaction in
individuals with a personal or family history of
allergic manifestations. It is characterized by flares
of congestion resulting in deep and superficial
blisters, followed by peeling, scaling, and a dry,
reddened surface. Flares generally result from
contact with irritants, but stress is also a significant
factor.
Seborrheic Dermatitis
Seborrheic dermatitis is generally limited to the scalp;
however, dry scales and underlying erythema can
occur on the face, ears, chest, back, and body folds.
Skin may be dry or oily. In infants, a widespread
reaction is associated with minimal discomfort. The
yeast organism, Pityrosporum, may be a factor. Mild
scaling without any erythema is often termed simple
dandruff. Tinea capitis may simulate dandruff or seborrheic dermatitis, and
scrapings should be taken for KOH examination and fungal culture, especially
in children, if hair loss is present.
Nummular Dermatitis
A pruritic dermatosis, characterized by round to oval
(coin-shaped) areas of vesiculation, superficial
crusting, and redness. Number of lesions varies from
few to many. More often this is a symmetrical
pattern in young adults. Not related to atopic
dermatitis.
Tinea Capitis
Along with hair loss, the scalp surface shows
seborrheic dermatitis-like scaling, impetigo-like
crusting, pustules, inflammatory nodules or kerion.
Identify tinea with KOH culture onto a fungal media.
No longer a disease confined to children. If infection
suspected, all family members should be examined.
Tinea Versicolor
Asymptomatic to mildly itchy macules that scale
readily on scraping. Lesions, usually occur on the
trunk, but may appear on upper arms, neck, face,
and groin. Caused by a yeast organism,
Pityrosporum orbiculare. Altered pigmentation can
be very subtle to obvious, both hypo and
hyperpigmented. KOH shows characteristic spores and hyphae. Fungal culture
is not useful.
Candidiasis
Common normal flora, but it may become an
opportunistic pathogen widespread in patients with
AIDS and other immunosuppressed patients.
Mucocutaneous candidiasis occurs on the vulva, anus,
breast or groin folds. Superficial denuded beefy red
areas with or without scattered satellite
vesicopustules with marginal scaling. Microscopic examination with 10%
KOH reveals budding spores and short hyphae.
Erythema Chronicum Migrans
Lyme Disease
Caused by the spirochete Borrelia burgdorferi, which
is transmitted to humans by a deer tick bite, infection,
is characterized by erythema migrans. A flat or
slightly raised red lesion appears at the site. The
reaction can become quite large, is generally circular
in shape, and can show several concentric rings
(target pattern). Erythema migrans is often accompanied by flu-like illness
with fever, chills, and myalgias. At this stage, laboratory tests are not reliable.
Actinic Keratoses
Actinic keratoses are single or multiple, flesh
colored or slightly hyperpigmented, dry, rough,
scaly lesions which occur on skin exposed to the
sun. Cells are atypical, and they are considered to
be pre-malignant because some may eventually
become squamous cell cancers.
Basal Cell Carcinoma
This lesion represents 90% of skin cancers. Basal
cell carcinoma is the most common cancer. On the
face, it usually starts as a reddened papule or nodule
with a smooth surface and a translucent, pearly
quality. Because of a poorly formed stroma, it is
fragile and often bleeds. On the torso, the lesion has
an irregular surface, bright red color, sometimes scaly, with a distinct edge.
Histologic examination is required.
Squamous Cell Carcinoma
This lesion usually appears on skin that shows other
significant changes of chronic sun exposure.
Especially prevalent in fair-skinned people who
sunburn easily and tan poorly. It may arise out of
actinic keratoses. Characteristically, the lesion
appears fairly rapidly as a small red, conical, hard
nodule. Should it appear on the mucus membrane or lip area, it behaves much
more aggressively and can be fatal. Histologic examination is required.
Malignant Melanoma
Recognized through the mnemonic, "A-B-C-D:"
Asymmetry of contour, irregularity of Border and
Color, and Diameter larger than 6 mm. Melanomas
vary from macules to nodules. Color ranges from
flesh tints to pitch black and mixtures of white, blue,
purple, and red. Any pigmented skin lesion with
recent change in appearance should be suspected.
Malignant melanoma can exist in a superficial spreading mode for years and
still be curable by excision with 1 to 2 cm margins. Once a vertical growth
phase develops, rapid spread through blood and lymph vessels occurs.
Histologic examination is required.
Atypical Moles
Dysplastic change implies abnormal cell
development, which does not necessarily imply
precancerous change. These atypical moles, show
irregular outlines, and different shades and patterns
of brown color. If they appear in a person with a
family history of melanoma and are multiple in
number, the incidence of cancer developing reaches
100%. If they are sporadic in pattern and number,
they should be photographed and reexamined
regularly. Histopathologic examination is required.
Psoriasis of the Nails
Pitting of nail surface with spots of white to yellow
brown (oil droplets) reflects psoriatic changes in the
nail matrix and nail bed respectively. Distally, there
are irregular onycholysis, splitting, and dystrophic
changes. Onycholysis may simulate onychomycosis;
therefore, fungal culture will be valuable in
diagnosis.
Intertriginous Psoriasis
Sebopsoriasis
The skin fold areas are shades of red and orange,
with mild to severe itching. The characteristic sign
is the uniform appearance (unlike tinea) and distinct
border (unlike candida). Generally, a complete skin
exam will reveal other signs of psoriasis.
Psoriasis of the Scalp
The lesions are red, sharply defined plaques covered
with thick silvery scales. This distinguishes psoriasis
from the diffuse or patchy redness and scaling of
seborrheic dermatitis.
Pustular Psoriasis
Generally, a chronic, disabling condition of the
palms and soles, it can also be a part of a very
severe generalized reaction.
Guttate Psoriasis
A form of psoriasis characterized by the rapid
development of myriad small lesions, 3 to 10 mm in
diameter, on all areas of the body, especially the
extremities. More often seen in young people.
Herpes Simplex, Penis
Red, sharply marginated, grouped vesicles usually
become crusted sores within 48 hours. Typical
distribution includes prepuce, coronal sulcus, glans,
shaft. Deep aching pain of the perineum may occur
2 to 3 days before appearance of the skin lesions.
Itchy and painful, lesions generally recur in the
same location.
Herpes Simplex, Vulva
Painful, recurrent, grouped vesicles. Viral
shedding occurs even when no lesions are present.
This sexually transmitted disease can complicate
pregnancy.
Herpes Simplex, Perineum
Recurrence of painful sores is a diagnostic sign.
Herpes Simplex in AIDS
Lesion in the perianal area becomes a deeply
ulcerated, very painful, disabling infection.
Condyloma Acuminatum
Genital Warts
Highly contagious and sexually transmitted, soft,
skin-colored, fleshy warts can be pin-head papules
or cauliflower-like masses that are caused by the
human papilloma virus. On the vulva, perianal area,
vaginal walls, cervix, or on the shaft of the penis,
warts can be raised clusters and obviously wart-like, or so small they only
become recognizable after application of 5% acetic acid (vinegar) for ten
minutes. Lesions must be distinguished from condylomata lata caused by
syphilis. Diagnosis of syphilis is based on a positive serologic test or discovery
of Treponema pallidum on darkfield examination.
Secondary Syphilis
Generalized maculopapular eruptions are most
common, although lesions may be pustular or
follicular as well (or combinations of any of these
types). Condylomata lata are raised, weeping
papules on the moist areas of the skin and mucous
membranes. The patient generally feels sick, can
have regional lymphadenopathy, but complains only of minimal itching.
Diagnosis of syphilis is based on a positive serologic test or discovery of
Treponema pallidum on darkfield microscopy.
Scabies
Scabies is a common dermatitis caused by
infestation with Sarcoptes scabiei. The entire
family may be affected. Skin lesions are scattered
groups of pruritic vesicles and pustules in "runs" or
"burrows" on the sides of the fingers, palms, wrists,
elbows, axillae, as well as around the waist and
groin. Itching occurs almost exclusively at night.
Microscopic examination of a scraping will reveal scabies mites, ova, and
feces.
Pediculosis
Lice
Pediculosis is a parasitic infestation of the skin of the
scalp, trunk, or pubic areas. Itching may be very
intense and scratching may result in deep
excoriations over the affected area. Head lice are
easiest to see above the ears and at the nape of the neck. The nits (egg sacs) are
attached to hairs, close to the skin. Body lice deposit visible nits on vellus hair.
Head and body lice are similar in appearance and are 3 to 4 mm long.
Papular Urticaria
Almost exclusively in children, this is a widespread
reaction to insect bites such as fleas, bedbugs,
chiggers, or gnats, and may persist for long periods.
The tendency will fade with onset of adolescence.
Urticaria
Usually intensely itching intradermal vascular
reaction (wheals or hives). No epidermal changes
such as scaling, papules, or blisters. More often has
an unknown, nonspecific etiology, but can be
related to medications, foods, and similar vascular
stimulating agents. Laboratory studies are not likely
to be helpful in evaluation unless there are sugges
tive findings in the history and physical examination.
Molluscum Contagiosum
Caused by a large pox virus, these smooth-walled,
dome-shaped, pearly papules, 2 to
5 mm in size, have an umbilicated center.
Occasionally a significant inflammatory reaction
will occur. Principal sites are face, hands, lower
abdomen, and genitals. A common viral infection
seen in AIDS. It is more difficult to eradicate in
these patients.
Herpes Simplex
Small red-ringed blisters can occur anywhere,
especially around oral and genital areas. Associated
and often preceded by burning and stinging.
Regional lymph nodes may be swollen and tender.
Blisters rupture early, leaving serous crusts which
can then become secondarily infected. Viral cultures
and ELISA are positive.
Herpes Zoster
Red-ringed blisters occur in a dermatomal
distribution of a nerve root. Papules change to
vesicles which become pustules before crusting.
New lesions appear for up to one week. Regional
lymph glands may be tender and swollen. Since this
is primarily a nerve infection with secondary skin
manifestations, it is preceded, accompanied, and
followed by pain. In elderly patients, it is often severe and prolonged. In
immunosuppressed patients, herpes zoster may disseminate, producing lesions
beyond the dermatome, visceral lesions, and encephalitis. Disseminated Zoster
is a serious, sometimes life-threatening complication.
This post was last modified on 30 November 2021