NCM109 THEORY

• Scabies


  Human scabies is caused by an infestation of the skin by the human itch mite Sarcoptes scabiei var. hominis
• Scabies


  • The microscopic scabies mite burrows into the upper layer of the skin where it lives and lays its eggs
  • A readily treatable infestation, scabies remains common primarily because of diagnostic difficulty, inadequate treatment of patients and their contacts, and improper environmental control measures
  • Scabies is a great clinical imitator; its spectrum of cutaneous manifestations and associated symptoms often results in delayed diagnosis
• The term "7-year itch" was first used with reference to persistent, undiagnosed infestations with scabies
• Transmission of scabies


  1. Predominantly through direct skin-to-skin contact

  2. Sarcoptes scabiei var hominis is a human itch mite, that transmits the disease

  3. The female S. scabiei var hominis mite lays 60-90 eggs in her 30-day lifespan, although less than 10% of the eggs result in mature mites

  4. Eggs incubate and hatch in 3-4 days (90% of the hatched mites die)

  5. Larvae (3 pairs of legs) migrate to the skin surface and burrow into the intact stratum corneum to make short burrows, called molting pouches (3-4 days)

  6. Larvae molt into nymphs (4 pairs of legs), which molt once into larger nymphs before becoming adults

  7. Mating takes place once, and the female is fertile for the rest of her life; the male dies soon after mating

  8. The female makes a serpentine burrow using proteolytic enzymes to dissolve the stratum corneum of the epidermis, laying eggs in the process; she continues to lengthen her burrow and lay eggs for the rest of her life, surviving 1-2 months

  9. Transmission of impregnated females from person-to-person occurs through direct or indirect skin contact
• Types of scabies


  • Classic scabies
  • Crusted scabies
  • Nodular scabies
• Classic scabies


  In classic scabies infection, typically 10-15 mites (range, 3-50) live on the host; little evidence of infection exists during the first month (range, 2-6 wk), but after 4 weeks and with subsequent infections, a delayed type IV hypersensitivity reaction to the mites, eggs, and scybala (feces) occurs
• Crusted scabies


  Crusted, or Norwegian, scabies (so named because the first description was from Norway in the mid-1800s) is a distinctive and highly contagious form of the disease; in this variant, hundreds to millions of mites infest the host individual, who is usually immunocompromised, elderly, or physically or mentally disabled and impaired
• Nodular scabies


  Nodules occur in 7-10% of patients with scabies, particularly young children; in neonates unable to scratch, pinkish brown nodules ranging in size from 2-20 mm in diameter may develop
• Causes of scabies


  • Sexually active individuals
  • Presence of many children in the household
  • Poor housing
• When a person is infested with scabies mites the first time, symptoms usually do not appear for up to two months (2-6 weeks) after being infested; an infested person still can spread scabies during this time even though he/she does not have symptoms
• Skin rash


  The most common symptoms of scabies, itching and a skin rash, are caused by sensitization (a type of "allergic" reaction) to the proteins and feces of the parasite
• Pruritus


  Severe itching (pruritus), especially at night, is the earliest and most common symptom of scabies
• Scabies rash


  A pimple-like (papular) itchy (pruritic) "scabies rash" is also common
• Burrows in skin


  Tiny burrows sometimes are seen on the skin; these are caused by the female scabies mite tunneling just beneath the surface of the skin; these burrows appear as tiny raised and crooked (serpiginous) grayish-white or skin-colored lines on the skin surface; burrows are a pathognomonic sign and represent the intraepidermal tunnel created by the moving female
• Common sites for scabies in older children and adults

  • Wrist
  • Elbow
  • Armpit
  • Nipple
  • Penis
  • Waist
  • Buttocks
  • Area between the fingers
  • Head
  • Face
• Burrow ink test


  A burrow can be located by rubbing a washable felt-tip marker across the suspected site and removing the ink with an alcohol wipe; when a burrow is present, the ink penetrates the stratum corneum and delineates the site; this technique is particularly useful in children and in individuals with very few burrows
• Tetracycline


  Topical tetracycline solution is an alternative to the burrow ink test; after application and removal of the excess tetracycline solution with alcohol, the burrow is examined under a Wood light; the remaining tetracycline within the burrow fluoresces a greenish color; this method is preferred because tetracycline is a colorless solution and large areas of skin can be examined
• Skin scraping


  Definitive testing relies on the identification of mites or their eggs, eggshell fragments, or scybala; this is best undertaken by placing a drop of mineral oil directly over the burrow on the skin and then superficially scraping longitudinally and laterally across the skin with a scalpel blade
• Adhesive tape test


  Strips of tape are applied to areas suspected of being burrows and then rapidly pulled off; these are then applied to microscope slides and examined; the adhesive tape test is easy to perform and had high positive and negative predictive values, making it a good screening test
• Scabies treatment


  Administration of a scabicidal agent (e.g., permethrin, lindane, or ivermectin), as well as an appropriate antimicrobial agent if a secondary infection has developed
• Activity


  Individuals affected by scabies should avoid skin-to-skin contact with others; patients with typical scabies may return to school or work 24 hours after the first treatment
• Decontamination


  Bedding, clothing, and towels used by infested persons or their household, sexual, and close contacts anytime during the three days before treatment should be decontaminated by washing in hot water and drying in a hot dryer, by dry-cleaning, or by sealing in a plastic bag for at least 72 hours
• Antiparasitic agents for scabies treatment

  • Topical options include permethrin cream (drug of choice), lindane, benzyl benzoate, crotamiton lotion and cream, sulfur, topical ivermectin, tea tree oil, or oil of the leaves of Lippia multiflora Moldenke, a shrub found growing in West African savanna
  • Oral options include ivermectin, although it has not been approved by US Food and Drug Administration (FDA) for the treatment of scabies
• Other agents used in scabies treatment

  • Topical antibiotics to treat secondarily infected lesions
  • Topical corticosteroids to help control intense pruritus
• Nursing assessment for scabies

  • History - Patient history can reliably suggest the presence of scabies; lesion distribution and intractable pruritus that is worse at night, as well as scabies symptoms in close contacts (including multiple family members), should immediately rank scabies at the top of the clinical differential diagnosis
  • Physical exam - Clinical findings include primary and secondary lesions; primary lesions are the first manifestation of the infestation and typically include small papules, vesicles, and burrows; secondary lesions are the result of rubbing and scratching, and they may be the only clinical manifestation of the disease
• Pediculosis


  An infestation of the hairy parts of the body or clothing with the eggs, larvae or adults of lice. Lice live on the host's skin surface and depend on the host for nourishment, feeding on human blood approximately five times daily. They inject their digestive juices and excrement into the host's skin and lay their eggs (i.e. nits) on hair shafts
• Types of lice


  • Pediculus capitis (head louse)
  • Pediculus corporis (body louse)
  • Crab louse
• Itching


  The most common symptom of a lice infestation is itching on the scalp, neck and ears
• Lice on scalp


  Lice may be visible but are difficult to spot because they're small, avoid light and move quickly
• Lice eggs (nits) on hair shafts


  Nits stick to hair shafts. Incubating nits may be difficult to see because they're very tiny
• Sores on the scalp, neck and shoulders

  Scratching can lead to small, red bumps that may sometimes get infected with bacteria
• Treatment for pediculosis capitis

  Involves the hair with a shampoo containing lindane (Kwell) or pyrethrin compounds with piperonyl butoxide (RID or R&C Shampoo). The patient is instructed to shampoo the scalp and hair according to the product directions
• Treatment for pediculosis corporis and pubis

  The patient is instructed to bathe with soap and water, after which lindane (Kwell) or 5% permetrhin (Elimite) is applied to affected areas of the skin and to hair areas, according to the product directions
• Cerebral Palsy


  One of the most complex of the common permanent disabling conditions
• Cerebral Palsy


  • Disorder of movement, muscle tone or posture
  • Caused by damage that occurs to the immature, developing brain, most often before birth
• Cerebral palsy is a group of conditions that affect movement and posture
• Cerebral palsy is caused by damage that occurs to the developing brain, most often before birth
• Symptoms of cerebral palsy appear during infancy or preschool years and vary from very mild to serious
• Children with cerebral palsy may have exaggerated reflexes
• Major types of cerebral palsy

  • Spastic
  • Athetoid
  • Ataxic
  • Rigidity
  • Mixed