MICRO EXAM #4

Anatomical diagnosis

Signs and symptoms of disease

Points of entry in skin

• Wounds

• Pores

• Circulation

Layers of skin (outer to inner)

1. Epidermis

2. Dermis

3. Subcutaneous

Bad environment for skin

• Low pH

• High salt

• Oils (sebum)

Physical skin defenses

• Keratin

• Cell sloughing (desquamation)

Normal flora diseases

• Staphylococcus epidermidis

• Corynebacterium diphtheriae

• Propionibacterium acne

• Candida sp. (fungus)

• Staphylococcus aureus

Lesions

Changes to skin caused by infection

Lesion types

• Rashes

• Pustules

• Warts

• Abscesses

Diagnostic indicators

Specific sign of a disease

Macule lesion

Flat and discolored spots

Ex. Vitiligo

Papule lesion

Raised and solid spots

Ex. Warts

Vesicle lesion

Filled with clear fluid spots

Ex. Blister

Pustule lesion

Filled with pus spots

Ex. Acne

Pus

Dead WBC’s + bacterial cells

Purulent

A fluid containing pus

Abscess lesion

A deep hard tissue pustule with decreased blood flow

Treatment of abscesses

Draining pustule to improve blood flow

Where is infections most serious?

Deeper in the skin

-itis

Infection or inflammation of

-emia

In the blood

Bacterial infections and skin

• Acne

• Dermatitis (Pseudomonas)

• Impetigo, folliculitis, cellulitis, necrotizing fasciitis

• MRSA skin infections

• Toxemias caused by Staphylococcus aureus

• Cutaneous anthrax

(Propionibacterium) Acne

• Anearobic

• Normal flora

• Opportunistic pathogen

Treatment for Acne

Antibiotics - topical and systemic

Epidemiology of Acne

Adults and adolescents

Dermatitis (Pseudomonas aeruginosa)

• Rash

• Strict aerobe

• Gram-negative rod

• Antibiotic resistant

• Opportunistic

• Nosocomial (hospital-associated)

Transmission of Dermatitis

Contact with contaminated water + soil

Odor of Dermatitis

Fruity / corn / Nike

Staphylococcus aureus

• Gram + cocci

• Breaches intact skin

• 30% normal flora

• Causes majority of skin infections

Transmission of Staphylococcus aureus

Direct or indirect contact

Treatment for Staphylococcus aureus

Antibiotics

Methicillin Resistant Staphylococcus aureus (MRSA) strains

• HA-MRSA (hospital-associated)

• CA-MRSA (community-associated)

MRSA transmission

Direct and indirect contact

MRSA prevention

• Hygiene practices

• Vaccinations

HA-MRSA treatment

Vancomycin

CA-MRSA treatment

Antibiotics

Epidemiology of CA-MRSA

Young adults

Epidemiology of HA-MRSA

Nursing homes + inpatient patients

HA-MRSA

• mecA gene present

• Resistant to all antibiotics except vancomycin

• Risk to hospital patients

CA-MRSA

• mecA gene present

• Resistant to methicillin, sensitive to other antibiotics

• Contains PVL gene

• Risk to everyone

Toxemia

Toxin enters bloodstream to cause disease, bacteria is not at site or in the blood

Scalded Skin Syndrome (SSS) is caused by

S. aureus toxic EXFOLIATIVE TOXIN

Process of SSS

1. Bacteria colonizes in newborn and children intestines

2. Exfoliative toxin is created

3. Toxemia

4. Epidermis is destroyed

5. Skin peels off in sheets

Staphylococcal Toxic Shock Syndrome (TSS) is cause by

S. aureus toxin TSST-1

Process of TSS

1. Bacteria colonizes in wounds, menstrual products, and after childbirth

2. Toxin is created

3. Toxemia

TSS symptoms

• Fever

• Vomiting

• Rash

• Skin shedding

Group A Streptococcus is also known as

GAS

Group A Streptococcus (GAS)

• Causes various skin infections

• Gram-positive cocci

Cutaneous anthrax (Bacillus anthracis)

• Endospores enter cuts/abrasions

• Large black lesions

Transmission of Cutaneous anthrax

Direct contact with endospores

Prevention for Cutaneous anthrax

Vaccinations for select groups

Viral infections and skin

• Measles

• Rubella

• Roseola

• Chickenpox/shingles

• Fifth disease

• Cold sores and herpes

• Hand, foot, and mouth disease

• Warts

Exanthem types

• Measles

• Rubella

• Roseola

• Chickenpox/shingles

• Fifth disease

Exanthems

• Viral diseases characterized by rashes

• Respiratory viruses

• Live attenuated vaccinations

Measles is also called

Rubeola

Most contagious virus

Measles

Measles is caused by

Measles virus

Signs and symptoms of Measles

• Macular rash

• Fever

• Cough

• Koplik spots

Koplik spots

Red patches with white centers

Diagnostic indicator for Measles

Koplik spots

Severe outcomes of measles

• Pneumonia

• Immune amnesia

• Subacute sclerosing panencephalitis (SSPE)

What type of vaccine is the MMR?

Live attenuated vaccine

MMR vaccine protects against

• Measles

• Mumps

• Rubella

Epidemiology of Measles

• Children

• Immunocompromised individuals

• Elderly

Cause of Rubella

Rubella virus

Signs and symptoms of Rubella

• Macular rash

• Fever

• Respiratory issues

Congenital rubella syndrome

Severe birth issues such as miscarriage, still birth, or birth defects

Epidemiology of Rubella

First trimester pregnancies

Cause of Roseola

Human herpesvirus 6 (HHV-6)

Signs and symptoms of Roseola

• Macular rash

• High fever

• Symptomatic for only a few days

Chickenpox is also known as

Varicella

Shingles is also known as

Zoster

Cause of Chickenpox + Shingles

Varicella-zoster virus

Signs and symptoms of chickenpox

• Vesicular rash

• Itchiness

• Fever

Transmission of Shingles

Contact from oneself and transmit to others

Epidemiology of Shingles

Older adults

Cause of Fifth disease

Parvovirus B19

Diagnostic indicator of Fifth disease

"Slapped cheek” rash

Sign and symptoms of Fifth disease

• Respiratory issues

• “Slapped cheek” rash

Epidemiology of Fifth disease

• Children

• Adults

• Fetuses

Cause of Cold sores

HSV-1

Cause of Herpes gladiatorum

HSV-1

Cause of Herpetic whitlow

HSV-1 or HSV-2

Diagnostic indicator of Herpes

Vesicular rash

Transmission of Herpes

Direct contact

Treatment of Herpes

Antivirals

Cause of HFMD

Coxsackievirus 16

Sign and symptoms of HFMD

• Vesicular rash

• Fever

• Enterovirus (infected gut)

Epidemiology of HFMD

Daycare children

Cause of Warts

Human Papillomavirus Virus (HPV)

Mycoses

Fungal diseases

Fungal infections and skin

• Ringworm (Tinea)

• Candidiasis

Ringworm is also known as

Tinea

Cause of Ringworm

Dermatophytes

Treatment for Ringworm

Anti-fungals

Prevention of Ringworm

Keep skin dry and clean

Cause of Candidiasis

Candida albicans

Signs and symptoms of Candidiasis

• Itchiness

• Red rash

Parasitic infections and skin

• Leishmaniasis

• Hookworm

• Scabies

• Lice

Cause of Leishmaniasis

Leishmania species (protozoan parasite)