Bacterial Diseases

Impetigo, cellulitis, folliculitis, furunculosis, carbuncle, erysipelas, necrotizing fasciitis, leprosy, cutaneous tuberculosis, staphylococcal scaled skin syndrome

Bacterial Diseases of the skin

impetigo

• Infection of the superficial layers of the epidermis

• Sores mainly occur around the nose and mouth in infants and children

impetigo

• Highly contagious skin infection > communicable

• Mostly affecting children 2 to 5 years of age

• Spread by direct contact

Staphylococcus aureus

• Gram positive

• Cocci in clusters

• Non-motile

• Non-spore-forming

• Facultative anaerobe

Staphylococcus aureus

• Protein A

• Capsule

• Hemolysin

• Leukocidins

• Coagulase

• Catalase Hyaluronidase

• Staphylokinase

Protein a

Surface protein embedded in the staphylococcus aureus

hemolysins

Toxins that can destroy blood cells

leukocidins

Destroy leukocyte(?)

coagulase

• Camoflauge

• Convert fibrinogen to fibrin

Catalase hyaluronidase

• Break down h2o2

• Destroy hyalauronic acid

staphyokinase

Breaks plasminogen to plasmin which destroys blood clot

streptococcus pyogenes

• Gram positive

• Cocci in chains or pairs

• Non-motile

• Non-spore forming

• Facultative anaerobe

Streptococcus pyogenes

• M protein (additional protective layer)

• Streptolysin o & s (break blood cells)

• Streptokinase

• Hyaluronidase

• Exotoxins (Spe A, B, C) - superantigens

Staphylococcus aureus, streptococcus pyogenes

Causative agents of impetigo

impetigo (ss)

• Pruritus (itchy)

• Localized erythema (redness of the skin or mucous membrane)

• Pustules/vesicles that crust with honey-colored apperance

Impetigo (s/d)

• Clinical exam

• Gram stain and culture of lesion swab

• Rapid GAS tests sometimes used

Impetigo (ni)

• Gently cleanse lesions with mild antiseptic

• Apply topical antibiotics as prescribed

• Educate patient on hand hygiene and avoiding scratching or sharing personal items

cellulitis

An acute bacterial infection that leads to inflammation of the deeper layers of the skin and underlying subcutaneous tissue

cellulitis

It usually affects the lower areas of the body, such as the legs, feet, and toes, but it can develop anywhere. It is also frequently seen on the face, arms, hands, and fingers

Staphylococcus aureus, streptococcus pyogenes

Causative agents of cellulitis

Cellulitis (ss)

• Erythematous

• Tender swelling

• Fever

• May have lymphangitic streaking

Cellulitis (s/d)

• Clinical diagnosis

• Wound culture or aspirate if purulent (formation of pus)

• Blood cultures if systemic

Cellulitis (ni)

• Monitor affected area for progression

• Elevate affected limb for circulation of blood

• Administer prescribed antibiotics

• Apply warm compresses

• Educate patient on completing antibiotic course

folliculitis

Common skin condition that happens when hair follicles become inflamed. Its often caused by an infection with bacteria

Staphylococcus aureus, pseudomonas aeruginosa

Causative agents of folliculitis

Folliculitis (ss)

• Superficial pustules centered on hair follicles

• Pruritus

• Localized erythema

Folliculitis (s/d)

• Clinical exam

• Culture of pustules if recurent or severe

Folliculitis (ni)

• Encourage avoidance o irritants

• Apply topical antiseptics

• Administer antibiotics for extensive infection

• Advise patient to avoid shaving or occlusive clothing

furunculosis

Boils or furuncles, are painful, pus-filled skin lesions that develop due to a deep infection of a hair follicle

furunculosis

Staphylococcal bacteria commonly reside harmlessly on the skin or in the nasal passages of many individuals, who serve as carriers without showing sins of infection

Staphylococcus aureus, others

Causative aents of furuncolosis

Furunculosis (ss)

• The most common areas for boils to occur are places where there is friction

• The center of the boil eventually becomes filled with yellow or white pus

• Painful, fluctuant nodules/abscesses

furunculosis (s/d)

• Clinical diagnosis

• Culture of pus

• Nasal carriage screening

Furunculosis (ni)

• Apply warm moist compresses to promote drainage

• Maintain aseptic technique during drainage

• Administer antibiotics

• Teach proper hygiene to prevent recurrence

carbuncle

Referes to a cluster of interconnected boils that develop within a localized area of infection

carbuncle

Involves a deeper and more expensive infection, often resulting in scarring

Staphylococcus aureus

Causative agent of carbuncle

Carbuncle (ss)

Multiple draining sinuses

Systemic symptoms (fever) possible

Carbuncle (s/d)

• Clinical diagnosis

• Culture of drainage

• Blood cultures if febrile (showing signs of fever)

Carbuncle (ni)

• Provide wound care post-infection and drainage

• Monitor for systemic infection

• Administer antibiotics

• Encourage fluid intake and proper nutrition to promote healing

erysipelas

A skin infection that affects the dermis and may extend to the superficial cutaneous lymphatic vessels

erysipelas

It presents as a well-defined, raised area of erythema, most commonly occuring on the lower extremities, with the face being the next most frequent site of involvement

Group a beta hemolytic streptococci, streptococcus pyogenes

Causative agents of erysipelas

Erysipelas (ss)

• Well-demarcated raised erythematous plaque

• Fever

• Lymphadenpathy(swelling of lymph node)

Erysipelas (s/d)

• Clinical diagnosis

• Blood cultures if sever

Erysipelas (ni)

• Monitor for systemic signs (fever, tachycardia (abnormal fast heartbeats))

• Administer antibiotics

• Apply cool compresses for comfort

• Educate patient on skin care and infection

Necrotizing fasciitis

Known as flesh-eating disease, is a bacterial infection that affects fascia

Necrotizing fasciitis

Pathogens enter the body through openings in the skin, such as cuts, burns, or wounds. Once inside, the bacteria produce toxins that quickly damage tissues, destroyblood cells, and spread throughout the body

Necrotizing fasciitis (risk factors)

• Diabetes

• Weakened immunity

• Intravenous drug use

• injuries

Group a streptococcus, staphylococcus aureus, vibrio vulnificus others

Causative agents of necrotizing fasciitis

Necrotizing fasciitis (late ss)

• Reddened and/or discolored skin

• Swelling of affected tissues

• Unstable blood flow

• Blisters filled with bloody or yellowish fluid

• Tissue necrosis

• Low blood pressure

• sepsis

Necrotizing fasciitis (late ss)

• Severe pain out of proportion

• Rapid spread, systemic toxicity

• Crepitus if gas-forming organisms present ( bubbles underneath the skin)

Necrotizing fasciitis (s/d)

• Clinical suspicion

• Imaging for gas

• Surgical exploration

• Tissue and blood cultures

• Tissue biopsy

Necrotizing fasciitis (ni)

• Provide aggressive wound care and sterile dressing changes

• Monitor vital signs closely

• Assist with surgical debridement preparation

• Provide pain management and emotional support

Leprosy (Hansen disease)

A chronic infectious condition that primarily affects the skin, peripheral nerves, mucous membranes of the upper respiratory tract, and the eyes

Mycobacterium leprae

• Acid-fast bacilli

• Non-motile

• Non-spore forming

• Obligate aerobe

• Phenolic glycolipid-1

• Lipoarabinomannan

• Mycolic acids

Mycobacterium leprae

Causative agent of leprosy

leprosy

Some people may have genetic predisposition to __

Leprosy (ss)

• Hypopigmented or erythematous anesthetic skin lesions

• Thick, stiff, or dry skin

• Painless swelling or lumps on the face or earlobes

• Peripheral nerve thickening

• neuropathy

Leprosy (s/d)

• Skin biopsy with AFB staining

• PCR

Leprosy (ni)

• Administer multidrug therapy as prescribed

• Monitor for serve damage

• Provide skin care and prevent injury due to loss of sensation

• Offer psycosoocial support to reduce stigma

Cutaneous tuerculosis

Rare form of extrapulmonary tuberculosis

Cutaneous tuberculosis

Only % to 2% develop __ . This form is more frequently observed in regions with high HIV prevalence or in populations with compromised immune systems

Mycobacterium tuberculosis, mycobacterium bovis, bacillus calmetter guen (bcg)

Causative agents of cutaneous tuberculosis

Mycobacterium tuberculosis

• Acid-fast bacilli

• Non-motile

• Non-spore forming

• Obligate aerobe

• Mycolic acids

• Heat shocks proteins

• Cord factor

• lipoarabinomannan

Mycobacterium tuberculosis

Causative agent of cutaneous tuberculosis

Cutaneous tuberculosis (ss)

• Chronic, slowly progressive lesion

• Central atrophy or scarring

• Usually painless or mildly tender

• May have serous or purulent discharge

• Ulcers with irregular, undermined edges

• lymphadenopathy

Cutaneous tuberculosis (s/d)

• Skin biopsy with AFB stain and culture

• PCR

• Tuberculin/IGRA supportive

Cutaneous tuberculosis (ni)

• Administer anti-TB medications as ordered

• Monitor adherence and side effects

• Promote good nutrition and rest

• Educate patient about long term therapy importance

Staphylococcal scalded skin syndrome

Is a serious skin disorder resulting from a systemic infection caused by toxin-producing staphylococus bacteria

Staphylococcal scalded skin syndrome

It predominantly affects children and immunocompromised adults, characterized by extensive skin peeling and redness

Staphylococcus aureus

Causative agent of Staphylococcal scalded skin syndrome

Staphylococcal scalded skin syndrome (ss)

• Fever

• Widespread erythema

• Blistering with positive nikolsky sign

• Mainly affects neonates/young children

Staphylococcal scalded skin syndrome (s/d)

• Clinical diagnosis

• Culture of primary infection site

• Histology supportive

Staphylococcal scalded skin syndrome (ni)

• Maintain skin integrity with steil dressing

• Monitor fluid and electrolyte balance

• Provide antibiotics and pain management

• Implement strict infection control