micro chap 18

-also known as rubeola
-sore throat, dry cough, headache, conjunctivitis, lymphadenitis, and fever
-Koplik's spots appear then turn into red maculopapular exanthem
-erupts on the head then progresses to the trunk and extremities until most of the body is covered
-complications can result
*pneumonia
*laryngitis
*secondary bacterial infections
*subacute sclerosing pancephalitis (SSPE)

-also known as German measles
-relatively minor rash disease with few complications
-two forms:
*postnatal infection
*congenital infection
-teratogenic virus
-transmission of virus to a fetus in utero
-mother can transmit the virus even if she is asymptomatic
-fetal injury varies depending on the time of infections

-Erythema infectiosum
-"slapped cheek" appearance
-spreads on the body but is most prominent on arms, legs, and trunk
-maculopapular, blotches run together
-low-grade fever and malaise

-common in young children and babies
-most cases proceed without the rash stage; others result in maculopapular rash
-high fever
-fourth day, fever disappears, and rash can appear

-most often the result of a respiratory infection with Streptococcus pyogenes
-causes strep throat

-caused by viruses
-most caused by one of more than 80 human papilomaviruses (HPVs)

-also known as papillomas
-affect children more than adults
-benign squamous epithelial growths
-varioud types
*seed
*genital
*plantar

-smooth waxy nodules on the face, trunk, and limbs
-may be indented in the middle
-may contain milky fluid
-common in children
-most often causes nodules on the face, arms, legs, and trunk in children; mostly in genital areas in adults

-Leishmaniasis
-Cutaneous anthrax

-zoonosis transmitted by female sand flies
-several different forms, depending on the species that is involved
*cutaneous
*espundia
*systemic

-most common and least dangerous version of infection with Bacillus anthracis
-caused by endospores entering the skin through small cuts or abrasions
-papule that becomes increasingly necrotic then ruptures to form a black eschar

-dermatophytes
-confined to the nonliving epidermal tissues and their derivatives
-different names all beginning with the word tinea

-ringworm of the scalp
-common in children
-small scaly patches to a severe inflammatory reaction to destruction of the hair follicle and temporary or permanent hair loss

-ringworm of the beard
-aka barber's itch
-chin and beard of adult males

-ringworm of the body
-prevalent infection of humans
-can appear nearly anywhere on the body's glabrous skin
-usually appears as one or more scaly reddish rings on the trunk, hip, arm, neck, or face

-ringworm of the groin
-also known as jock itch
-thrives under conditions of moisture and humidity caused by sweating

-ringworm of the foot
-also known as athlete's foot and jungle rot
-connected to wearing shoes-keep feet in a closed, warm, moist environment

-ringworm of the hand
-almost always associated with concurrent infection of the foot
-usually occur on the fingers and palms of one hand

-ringworm of the nail
-superficial white patches in the nail bed, or thickening, distortion, and darkening of the nail
-artificial fingernails can provide a portal of entry into the nail bed

-involve the outer epidermal surface
-ordinarily innocuous infections with cosmetic rather than inflammatory effects
-tinea versicolor caused by Malassezia furfur

-chronic Chlamydia trachomatis infection of the epithelial cells of the eye
-major causes of blindness in certain parts of the world
-first signs of infection-mild conjunctival discharge and slight inflammation of the conjunctiva
-followed by marked infiltration of lymphocytes and macrophages
-as these cells build up, they impart a pebbled appearance to the inner aspect of the upper eyelid
-eventually, pannus occurs

-more serious infection than conjunctivitis
-invasion of deeper eye tissues occurs, can lead to complete corneal destruction
-any microorganism can cause this condition
-one of the more common causes: herpes simplex virus
-preliminary symptoms: gritty feeling in the eye, conjunctivitis, sharp pain, and sensitivity to light

-chronic parasitic (helminthic) infection
-Onchocerca volvulus transmitted by black flies
-the worms eventually invade the entire eye, producing inflammation and permanent damage to the retina and optic nerve