Micro E4

What is an exanthem?

A widespread skin rash with systemic symptoms like fever, malaise, and headache.

What is an enanthem?

A rash on mucous membranes.

What are rash diseases commonly caused by?

Infectious agents (like viruses or bacteria).

What are macular rashes?

Flat, red spots less than 1 cm in diameter; like moles

What are papular rashes?

Small, solid, raised (elevated) lesions.

What are maculopapular rashes?

A mixture of macules and papules (e.g., measles).

What are vesicular rashes?

Small, fluid-filled blisters (e.g., shingles).

What are pustular rashes?

Blisters filled with pus (e.g., Staphylococcus infections).

Which structures of the eye are most commonly infected?

The cornea and the conjunctiva.

What type of infection is commonly associated with the cornea?

Infections related to contact lens use.

What are the main maculopapular rash diseases?

Measles (rubeola), rubella (German measles), fifth disease, and roseola.

What causes Measles (rubeola) and rubella (German measles)

A single-stranded RNA virus.

What is the portal of entry for measles?

Respiratory droplet contact.

What happens during the prodromal period of measles?

Cold/flu-like symptoms appear.

What type of rash is associated with measles and german measles?

Maculopapular rash.

What is a common fever associated with measles?

High fever (around 104°F).

What are Koplik’s spots?

White spots on the buccal mucosa.

Who is at highest risk for severe measles complications?

Immunocompromised patients.

What is acute disseminated encephalomyelitis (ADEM) in measles?

A serious complication that may occur during recovery.

What is subacute sclerosing panencephalitis (SSPE)?

A delayed, fatal brain disorder that can occur 7–10 years after measles infection.

What is symptomatic care?

treatment that focuses on relieving/managing symptoms rather than curing the disease.

What is another name for rubella?

German measles or 3-day measles.

What type of rash is seen in rubella?

A maculopapular rash.

What is the status of rubella in the United States?

Declared eliminated in 2004 but still endemic worldwide.

How does the rubella rash spread on the body?

Starts on the head and spreads outward (centrifugal).

What type of fever is associated with rubella?

Low-grade fever.

How can rubella affect adults?

It can cause joint pain.

Why is rubella dangerous during pregnancy?

It can cross the placenta and cause severe birth defects or death of the fetus.

How is measles(rubeola) and German mealses rubella treated?

With symptomatic care

Why can’t pregnant women receive the rubella vaccine?

It is a live attenuated (weakened) virus vaccine that could cross the placenta and harm the fetus.

What causes fifth disease/(erythema infectiosum)?

Human parvovirus B19.

What is the portal of entry for fifth disease(Human parvovirus B19)?

Respiratory tract.

What are the prodromal symptoms of Human parvovirus B19.?

Fever and cold/flu-like symptoms.

What is the characteristic rash of Human parvovirus B19 disease?

“Slapped-cheek” rash.

What viruses cause Roseola (Roseola Infantum)?

Human herpesvirus 6 and 7 (HHV-6/7).

Who is most commonly affected by roseola?

Young children, usually under 3 years old.

How is roseola transmitted?

Respiratory secretions or saliva.

What is a key feature of roseola before the rash appears?

3–5 days of very high fever (over 104°F).

What happens after the fever in roseola?

A sudden maculopapular red rash appears.

How is roseola treated?

Antipyretics for fever and symptomatic care.

What virus causes chickenpox?

Varicella-zoster virus (VZV), a herpesvirus.

What disease results from the initial exposure to VZV?

Chickenpox.

What happens to VZV after the initial infection

It incorporates into host cell DNA and remains dormant.

What condition occurs when VZV reactivates later in life?

Shingles (herpes zoster).

What commonly triggers herpesvirus reactivation?

Immunosuppression or weakened immune system.

How is chickenpox transmitted?

By inhalation of infected particles from skin lesions.

What type of lesions are produced in chickenpox?

Vesicular lesions that scab over.

What is the shingles rash also called?

Dermatomal rash.

What treatments are used for chickenpox itching?

Antihistamines, oatmeal baths, and calamine lotion.

What antiviral medication used for chickenpox in severe or complicated cases.

Valacyclovir.

What medication is used for nerve pain in shingles?

Gabapentin.

What type of vaccine is the varicella (chickenpox) vaccine?

A live attenuated vaccine.

When is the varicella vaccine given?

As part of the routine childhood immunization schedule.

Is there a vaccine for shingles?

Yes, for older individuals.

What diseases are caused by herpes simplex viruses?

Painful Cold sores and genital herpes.

What are the two types of herpes simplex virus?

HSV-1 and HSV-2.

Can herpes simplex viruses affect the central nervous system?

Yes, they can cause encephalitis; rare

How is herpes simplex transmitted?

Through direct person-to-person contact.

Where does herpes simplex virus become latent?

In nerve ganglia.

Which virus primarily causes cold sores?

HSV-1.

Is there a vaccine for herpes simplex virus?

No.

What is the main treatment for herpes simplex infections?

Antiviral medications: Acyclovir and valacyclovir.

Which type of HSV primarily causes genital herpes?

HSV-2.

How is HSV-2 transmitted?

As a sexually transmitted disease (STD).

Can HSV-1 and HSV-2 infect different body areas than usual?

Yes, HSV-1 can infect genital areas and HSV-2 can infect oral areas.

What causes warts (papillomas)?

Human papillomavirus (HPV).

How is HPV transmitted?

Through direct or sexual contact.

How does HPV cause warts?

Viral proteins disrupt cell growth control, causing uncontrolled cell replication.

What treatments are used for warts?

Freezing (cryotherapy), burning, and surgical removal.

Which HPV types cause most genital warts?

HPV-6 and HPV-11.

What are genital warts also called?

Condyloma acuminata.

What is the vaccine for HPV

Gardasil 9.

When should the HPV vaccine be given for best effectiveness?

Before a person becomes sexually active.

What virus causes smallpox?

Variola virus.

What type of rash is associated with smallpox?

Pustular rash.

How is smallpox transmitted?

Through direct or indirect contact.

How can smallpox spread through the air?

By inhalation of aerosolized particles.

What organs does smallpox infect?

Internal organs and bone marrow.

What is an early sign of smallpox in the mouth?

Small spots on the oral mucosa (enanthem).

What severe outcome can smallpox lead to?

Sepsis and death.

Are there FDA-approved treatments for smallpox?

No, unless for military

Which Staphylococcus species are associated with skin infections?

Staphylococcus epidermidis and Staphylococcus aureus.

Where is Staphylococcus aureus normally found?

In the nares (nose).

What is the shape and arrangement of Staphylococcus bacteria?

Gram-positive cocci that grow in clusters.

How are many staph skin infections treated?

Surgical drainage and antibiotic therapy.

What do staphylococcal exotoxins do?

Damage host tissue and weaken immune defenses.

What is TSST and what does it cause?

Toxic shock syndrome toxin; a superantigen that causes toxic shock syndrome

What does the exfoliative toxin cause?

Scalded skin syndrome (blistering condition in children).

What is folliculitis?

A superficial infection of hair follicles.

What is a furuncle (boil)?

A deep infection of a hair follicle.

What is a carbuncle?

Multiple boils (furuncles) joined together.

What does MRSA stand for?

Methicillin-resistant Staphylococcus aureus.

What antibiotic is commonly used to treat MRSA?

Vancomycin.

Why is MRSA a concern?

Because it is resistant to many commonly used antibiotics.

What bacteria commonly cause impetigo?

Staphylococcus aureus and Group A Streptococcus (S. pyogenes)

What is the most common topical treatment for impetigo?

Mupirocin.

What oral antibiotics can be used to treat impetigo?

Cephalexin, trimethoprim-sulfamethoxazole, doxycycline, and clindamycin.

What organism causes many streptococcal skin infections?

Streptococcus pyogenes.

What is necrotizing fasciitis?

A severe “flesh-eating” infection of soft tissue.

How is necrotizing fasciitis treated?

With antibiotics such as vancomycin, daptomycin, clindamycin, and combination therapy (e.g., metronidazole).