Encyclopedia of Health and Medicine

148 The Integumentary System
environment that encourages a normally present
fungus, Malassezia (also called Pityrosporum), to
flourish in abundance. Malassezia subsists on
sebum, an oil substance the sebaceous glands
secrete. An overgrowth of Malassezia depletes the
sebum supply, causing the sebaceous glands to
increase sebum production. This in turn accelerates
cell growth, generating dandruff. Shampoos
and lotions containing an antifungal medication
such as ketoconazole reduces the scalp’s Malassezia
population, returning cell turnover to normal.
PRODUCTS TO CONTROL DANDRUFF
coal-tar extracts
glycolic acid
ketoconazole and other salicylic acid
antifungal shampoos tea tree oil
selenium sulfide
topical corticosteroids
zinc pyrithione
Risk Factors and Preventive Measures
Frequent or heavy use of hair products such as
hairsprays and styling gels can further clog the
sebaceous structures. Stress, hormones, and the
environment can precipitate or exacerbate dandruff.
Dandruff, or the skin conditions that establish
dandruff such as seborrheic dermatitis, are
more common in people who have PARKINSON’S
DISEASE, though the reason for this remains
unknown. People who are prone to dandruff that
worsens seasonally often can minimize the severity
of their symptoms by beginning therapeutic
efforts before flaking becomes a problem.
See also CORTICOSTEROID MEDICATIONS; CRADLE CAP;
HORMONE; KERATINOCYTE; KERATOSIS PILARIS; SEBA-
CEOUS GLAND; STRESS AND STRESS MANAGEMENT.
decubitus ulcer An erosion in the SKIN that
results from the pressure of remaining in one position
for an extended period of time, commonly
called a bedsore or pressure sore. The extended
pressure deprives the tissue of blood circulation,
allowing cells to die and the tissue to break down.
Tissues over areas where the bones are near the
skin are most vulnerable, such as the hips, ankles,
heels, elbows, shoulders, base of the spine, and
back of the head. Decubitus ulcers are a specific
risk for people who have debilitating conditions or
injuries that limit their mobility, particularly elderly
individuals in extended-care facilities. MALNU-
TRITION and age-related changes to the skin result
in fragility that makes the skin more susceptible to
damage.
Often, measures such as frequent changes of
position and soft surfaces to shelter the skin at
contact points can prevent decubitus ulcers.
Within contemporary quality of care standards
and guidelines in health care, decubitus ulcers
raise questions as to whether providers and facilities
are delivering appropriate care. Undetected or
untreated decubitus ulcers can result in significant
tissue loss and threaten overall health. Once
established, a decubitus ulcer requires aggressive
medical intervention to limit permanent tissue
damage and restore healthy skin.
CLINICAL STAGING OF DECUBITUS ULCERS
Clinical Stage Presentation Tissue Penetration
stage 1 nonblanching red area superficial layers of skin (epidermis, first layer of dermis)
stage 2 BLISTER or open sore full skin (epidermis and full thickness of dermis) to the underlying
FASCIA
stage 3 craterlike sore that oozes or bleeds; through the skin and fascia, into the supportive connective and
damaged or necrotic (dead) SKIN; fatty tissue
damage to underlying tissues
stage 4 deep ulcer that bleeds; extensive skin through the skin, fascia, and underlying structures into adjacent
and tissue destruction and necrosis MUSCLE, TENDON, and LIGAMENT, and JOINT