DERMATOLOGY
PREPARED BY MR. ABHIJIT DAS
PSORIASIS
DEFINITION
Psoriasis is a chronic autoimmune skin disease that
causes skin cells to grow too quickly, resulting in the development of thick,
red, scaly patches on the skin. These patches can be itchy, painful, and may
appear anywhere on the body, including the scalp, nails, and joints. Psoriasis
is caused by an overactive immune system, which mistakenly attacks healthy skin
cells.
ETIOPATHOGENESIS
1.
Genetic factors: Psoriasis has a strong
genetic component. Research has identified several genes that are associated
with psoriasis, including genes that regulate the immune system and genes that
control skin cell growth.
2.
Immune system dysfunction: In psoriasis,
the immune system mistakenly attacks healthy skin cells, causing inflammation
and the rapid growth of skin cells.
3.
Environmental triggers: Environmental
factors such as stress, infections, injuries to the skin, and certain
medications can trigger psoriasis in people who are genetically predisposed to
the disease.
4.
Abnormalities in skin cell growth: In
psoriasis, skin cells grow and divide more quickly than normal, resulting in
the formation of thick, scaly patches on the skin.
5.
Cytokine dysregulation: Cytokines are
proteins that play a key role in regulating the immune response. In psoriasis,
there is an overproduction of certain cytokines, which contribute to
inflammation and the development of psoriatic lesions.
CLINICAL MANIFESTATIONS
Psoriasis can present in different ways, but the
most common clinical manifestations include:
1.
Red, raised, scaly patches of skin:
These patches, also known as plaques, are the most common presentation of
psoriasis. They are typically thick, red, and covered in silvery-white scales.
2.
Itching and burning: Psoriasis plaques
can be itchy and/or painful, particularly if they crack and bleed.
3.
Nail changes: Psoriasis can cause
changes in the nails, including pitting, discoloration, thickening, and
separation from the nail bed.
4.
Joint pain and swelling: About 30% of
people with psoriasis develop psoriatic arthritis, which can cause joint pain,
swelling, and stiffness.
5.
Scalp involvement: Psoriasis can affect
the scalp, causing redness, scaling, and itching. This can result in
dandruff-like flakes and hair loss in severe cases.
NON-PHARMACOLOGICAL MANAGEMENT
1.
Moisturize: Keeping the skin
well-moisturized can help reduce dryness and itching associated with psoriasis.
Use fragrance-free and gentle moisturizers, and apply them after bathing or
showering.
2.
Avoid triggers: Identify triggers that
worsen psoriasis symptoms, such as stress, alcohol, smoking, and certain
medications. Avoiding or reducing exposure to these triggers can help improve
symptoms.
3.
Bathing: Taking a warm bath with
colloidal oatmeal, Epsom salts, or dead sea salts can help soothe the skin and
reduce itching.
4.
Sun exposure: Moderate sun exposure can
help improve psoriasis symptoms. However, it's important to protect the skin
from sunburn and skin damage, which can worsen symptoms.
5.
Stress management: Stress can trigger or
worsen psoriasis symptoms, so finding ways to manage stress, such as through
meditation, yoga, or counseling, can be helpful.
6.
Diet and exercise: A healthy diet and
regular exercise can help reduce inflammation and improve overall health, which
can in turn help improve psoriasis symptoms.
7.
Avoiding skin injury: Psoriasis plaques
can be easily irritated, so avoiding skin injury, such as cuts or scrapes, can
help prevent worsening of symptoms.
PHARMACOLOGICAL MANAGEMENT
1.
Topical corticosteroids: These are
anti-inflammatory creams or ointments that are applied directly to the skin.
They can help reduce itching, redness, and scaling.
2.
Vitamin D analogues: These topical
creams or ointments are derived from vitamin D and can help slow skin cell
growth and reduce inflammation.
3.
Topical retinoids: These are vitamin A
derivatives that can help normalize skin cell growth and reduce inflammation.
4.
Biologic agents: These are systemic
medications that target specific immune system proteins that are involved in
psoriasis inflammation. Examples include TNF inhibitors, IL-17 inhibitors, and
IL-23 inhibitors.
5.
Methotrexate: This is a systemic
medication that can help slow skin cell growth and reduce inflammation.
6.
Cyclosporine: This is a systemic
medication that can suppress the immune system and reduce inflammation. It is typically
used for short-term management of severe psoriasis.
7.
Acitretin: This is a systemic medication
that is derived from vitamin A and can help slow skin cell growth and reduce
inflammation.
SCABIES
DEFINITION
Scabies is a skin condition caused by a tiny mite
called Sarcoptes scabiei. The mite burrows into the skin, where it lays eggs
and causes an itchy rash. Scabies is contagious and can spread through close
physical contact with an infected person.
ETIOPATHOGENESIS
Scabies is caused by the infestation of the skin by
the Sarcoptes scabiei mite. The mite burrows into the skin, particularly in
areas where the skin is thin, such as the fingers, wrists, elbows, armpits,
genital area, and buttocks.
The female mite lays eggs in these burrows, and when
the eggs hatch, new mites emerge and continue to burrow and reproduce. This
cycle can cause an intense, itchy rash and skin irritation.
Scabies is primarily transmitted through close
physical contact with an infected person. It can also spread through sharing of
clothes, towels, and bedding. The mites can survive off the human body for a
few days, which means that contaminated surfaces can also spread the
infestation.
Certain factors can increase the risk of scabies
infestation, such as a weakened immune system, poor hygiene, and certain
medications. It's important to seek medical treatment if scabies is suspected
to prevent spreading the infestation to others and to relieve symptoms.
CLINICAL MANIFESTATIONS
1.
Intense itching: This is the most common
symptom of scabies and can be very intense, especially at night.
2.
Skin rash: The rash is usually red and
consists of small, raised bumps or blisters. It can appear in any part of the
body, but is more common in areas such as the hands, wrists, elbows, armpits,
genital area, and buttocks.
3.
Burrows: These are thin, grayish-white,
thread-like lines on the skin, which are caused by the mites burrowing into the
skin. They are often found in the folds of the skin.
4.
Sores: Scratching the rash can cause
sores and crusts, which can increase the risk of secondary bacterial
infections.
5.
Allergic reaction: Some people may
develop an allergic reaction to the mites, which can cause more severe itching
and skin irritation.
NON-PHARMACOLOGICAL MANAGEMENT
1.
Avoiding close physical contact: Scabies
is highly contagious, and it can spread through close physical contact with an
infected person. Avoiding such contact can help prevent the spread of the
infestation.
2.
Washing clothes and bedding: Washing clothes,
bedding, and towels in hot water and drying them on high heat can help kill the
mites and prevent re-infestation.
3.
Disinfecting surfaces: Disinfecting
surfaces, such as furniture, door handles, and light switches, can help kill
any mites that may have fallen off the body.
4.
Treating close contacts: Close contacts
of an infected person, such as family members and sexual partners, should be
treated at the same time to prevent re-infestation.
5.
Avoiding scratching: Scratching the skin
can cause sores and increase the risk of bacterial infections. Wearing gloves
or mittens at night can help prevent scratching.
6.
Maintaining good hygiene: Bathing
regularly and keeping the skin clean can help prevent secondary infections and
promote healing.
PHARMACOLOGICAL MANAGEMENT
1.
Topical creams and lotions: These
medications are applied directly to the skin and usually contain an insecticide
called permethrin. Permethrin kills the mites and their eggs. Other topical
medications that may be used include sulfur ointment and crotamiton lotion.
2.
Oral medications: In some cases, oral
medications such as ivermectin may be prescribed to treat scabies. Ivermectin
is an anti-parasitic medication that is taken orally, and it works by killing
the mites.
3.
Anti-itch medications: Itching is a
common symptom of scabies, and anti-itch medications such as antihistamines may
be prescribed to relieve this symptom.
ECZEMA
DEFINITION
Eczema, also known as atopic dermatitis, is a
chronic skin condition characterized by patches of inflamed, itchy, and dry
skin. It is a non-contagious condition that is believed to be caused by a
combination of genetic and environmental factors. Eczema can occur at any age
but is most common in infants and children. It can affect any part of the body
but is most commonly found on the face, neck, hands, and legs.
ETIOPATHOGENESIS
1.
Genetics: Eczema often runs in families,
suggesting that genetic factors may play a role. Studies have identified
several genes that may contribute to the development of eczema.
2.
Immune system dysfunction: Eczema is
thought to be caused by an abnormal immune response, in which the immune system
overreacts to environmental triggers and causes inflammation and skin damage.
3.
Environmental triggers: Environmental
factors, such as exposure to allergens, irritants, and pollutants, can trigger
or exacerbate eczema symptoms.
4.
Skin barrier dysfunction: The skin of
people with eczema is often dry and prone to irritation, which may be due to a
defect in the skin barrier that allows irritants to penetrate the skin and
trigger an inflammatory response.
CLINICAL MANIFESTATIONS
1.
Dry, itchy skin: Eczema is often
characterized by dry, itchy skin that may be red or inflamed.
2.
Rash: A rash may develop, consisting of
small raised bumps that may ooze or crust over.
3.
Swelling: The affected area may become
swollen and sore, particularly if it is scratched.
4.
Scaling: The skin may become scaly or
develop cracks, which can be painful and may increase the risk of infection.
5.
Thickening of the skin: In chronic cases
of eczema, the skin may become thick and leathery, particularly on the hands
and feet.
6.
Changes in skin color: Over time, the
affected skin may become darker or lighter in color than the surrounding skin.
7.
Blisters: Some types of eczema may cause
fluid-filled blisters to develop on the skin.
NON-PHARMACOLOGICAL MANAGEMENT
1.
Moisturize regularly: Keeping the skin
moisturized can help reduce dryness and itching. Use a moisturizer that is
gentle and fragrance-free.
2.
Use mild soaps: Use mild, fragrance-free
soaps when bathing or showering. Avoid hot water, which can strip the skin of
natural oils.
3.
Dress appropriately: Wear loose-fitting,
cotton clothing that is gentle on the skin. Avoid tight-fitting clothes that
can irritate the skin.
4.
Manage stress: Stress can trigger or
exacerbate eczema symptoms. Practice stress-reducing techniques such as yoga,
meditation, or deep breathing exercises.
5.
Maintain a healthy diet: Eating a
healthy, balanced diet can help support overall skin health. Focus on foods
that are rich in vitamins and minerals, such as fruits, vegetables, and whole
grains.
6.
Keep cool: Overheating can exacerbate
eczema symptoms, particularly in the summer. Keep cool by using a fan or air
conditioner, and avoid activities that can cause sweating.
PHARMACOLOGICAL MANAGEMENT
1.
Topical corticosteroids: These
medications reduce inflammation and itching and are available in a variety of
strengths. They are typically used for short periods of time to treat acute
flare-ups.
2.
Topical calcineurin inhibitors: These
medications suppress the immune system and can help reduce inflammation and
itching. They are typically used for long-term management of eczema.
3.
Topical immunomodulators: These
medications modify the immune response and can help reduce inflammation and
itching. They are typically used for long-term management of eczema.
4.
Topical antihistamines: These
medications can help reduce itching and are typically used for short periods of
time to treat acute flare-ups.
5.
Oral medications may be prescribed in
severe cases of eczema. These may include oral corticosteroids, which can help
reduce inflammation throughout the body, or immunosuppressants, which can
modify the immune response.