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Ulcerative or Necrotic Lesions


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Foot puncture with tennis shoes.
Burn or Wound Infections -
Ps. aeruginosa - foul green-pigmented discharge and necrosis; distant ecthyma gangrenosum indicated sepsis.
Etiology of burns?
Burns: S. aureus > Ps. aeruginosa, Proteus > GAS > other streptococci, Enterococci, Candida, Aspergillus
Etiology of surgical wounds?
S. aureus
Etiology of prosthetic heart valves, artificial joints, plastic devices?
Staph. epidermidis
Etiology of Catheters in place >48hr?
Gram - rods
Therapy of burns or wound infections:
S. pyogenes and S. aureus?
Ps. Aeruginosa?
S. pyogenes and S. aureus - Oral dicloxacillin
Ps. aeruginosa - Imipenem cilastatin
A 3 year old child presents with purulent lesions and/or honey-crusted scabs around the nose and mouth.
Manifestations of Impetigo?
Vesicles rupture > purulent erosions with honey-colored thick crusts
Etiology of Impetigo?
M protein type 49 with AGN
Infection usually limited to skin
Therapy - topical antibiotics
While on a medical mission, several subjects are seen with pyoderma and ulcers of the face and arms. Some individuals show a severe pharyngitis. Skin scrapings show Gram-positive rods.
Cutaneous Diphtheria
Etiology of Cutaneous Diptheria?
Corynebacterium diphtheriae
Epidemiology of Cutaneous Diptheria?
Transmitted by pharyngeal droplets, fomites or active skin infection (ulcers or normal appearing skin). Poor hygiene and warm climates increase infection rate.
An adult who has handled raw rabbit flesh or a person bitten by a tick who presents with fever, skin ulceration and regional lymphadenopathy. Serolgy shows B. abortus titer.
Diagnosis of Tularemia?
Cross reaction with B. abortus
Therapy: Gentamicin or Tobramycin
Responses to bite ranges from mild local urticarial (hive like) reactions to full thickness skin necrosis. Nonpainful bite but can progress to painful. Site of bite is white with red halo; vesiculates and becomes necrotic, leaving a gaping ulcer. Locatio
Loxoscelism (Brown spider bite)
Epidemiology of Loxoscelism?
Loxosceles reclusa, SOUTHEAST and MIDWEST
The primary lesion usually develops at the site of a minor scratch or abrasion; hemorrhagic necrotic ulcer covered by a black crust or eschar (malignant pustule); Dissemination
Cutaneous Anthrax
Etiology of Anthrax?
Etiology: Bacillus anthracis
Epidemiology: Spores are commonly found on animal skins, hides, or bone meal. Inoculation anthrax is commonly limited to skin.
Pathology of cutaneous anthrax?
3 factors of pathology: 1) Edema factor 2) Protective antigen (induces protective antibodies) 3) Lethal factor
Therapy: Ciprofloxacin
Red macules enlarge becoming slightly elevated papules, then hemorrhagic and necrotic centrally with purple to black coloration. Older lesions are ulcers with a hemorrhagic crust or eschar. Concurrent Gram-negative sepsis.
Ecthyma Gangrenosum
Epidemiology of Ecthyma Gangrenosum?
At risk: immunocompromised
Therapy: Imipenem and Meropenem (Pseudomonas)
A primary or herald lesion, occurs at bite site 1-2 weeks. Black eschar forms and inflammation is intense in the deeper layer of the dermis, where necrosis occurs. A generalized vesicular/papular rash occurs evenly distributed over the body except for th
Etiology of Rickettsialpox?
Rickettsia akari (obligate intracellular bacterium)
Therapy: Doxycycline
Contraindicated: Sulfonamides
Epidemiology of Rickettsialpox?
A benign urban disease that occurs when the mouse popularion increases to an unusually high level disease. Involves mainly adults, transmitted to man by a MITE
Papule, which ulcerates, becomes granulomatous. Location: knees, elbows, extremities at site of inoculation
Swimming pool granuloma (atypical mycobacterial infections)
Etiology of swimming pool granuloma?
Mycobacterium marinum, M. kansasii, M. intracellulare
Diagnosis: Acid fast stain, culture at 37 degree and 32 degree C; skin test with PPD
Epidemiology of Swimming pool granuloma?
M. marium most common in the US; fresh or salt water, contaminated swimming pools, or from cleaning a home aquarium
Later, multiple painless, red to violet ulcerated nodules develop along lymphatic channels that drain the initial lesion.
Sporotrichosis (Rose growers disease)
Etiology of Sporotrichosis?
Sporothrix schenckii
Lesions appear 7 days to 6 months after puncture wound inoculaton. Microscopy shows cigar shaped yeast
Epidemiology of Sporotrichosis?
Transmitted by puncture wounds that inoculate dust. ie: rose thorn punctures. AT RISK: gardeners, farmers, florist
Therapy: Oral itraconazole
A variety of lesions including cellulitis, pustules, abscesses and ulcerated nodules.
Primary cutaneous nocardiosis
Papules or nodules on the foot or hand slowly progress to indurated skin and soft tissue swelling with multiple sinus tracts draining sulfur granule filled pus
Mycetoma (Nocardiosis)
Etiology of Nocardiosis?
Epidemiology of Nocardiosis?
Spores introduced from soil into skin by trauma
Diagnosis of Nocardiosis?
Weakly GRAM POSITIVE and weakly ACID-FAST POSITIVE, beaded, branching filaments, AEROBIC culture
Subcutaneous indurated tissue containing multiple, small, communicating abscesses surrounded by granulation tissue from sinus tracts that communicate to the skin and drain a purulent discharge containing yellow sulfur granules.
other manifestations of actinomycosis?
ongoing infections of the jaw, pelvis, lung or GI tract are the source of the skin lesion
Etiology of Actinomycosis?
Actinomyces israelii
Dx: Branched and unbranched wavy filaments or as the distinctive sulfur granules. These consist of a central mass of tangled bacterial filaments, pus cells, and debris.
Pustular, papular, nodular, or ulcerated lesions, sometimes resembling acne, molluscum contagiosum, or basal cell carcinoma. Most patients with this disease have meningitis and/or pulmonary disease
Etiology of Cryptococcosis?
Cryptococcus neoformans
Worldwide distribution, associated with pigeon droppings. Infection results from inhalation of soil contaminated with the encapulated yeast.
Pathology of Cryptococcosis?
Patholgy: Involved tissues contain cystic masses of yeast that appear gelatinous because of accumulated cryptococcal capsular polysaccharide.
Diagnosis: Culture
Cutaneous and Mucocutaneous Leishmaniasis: types?
Old World Cutaneous (oriental sore, Delhi or Aleppo boil)
NW C (tropical sore, uta, chiclero ulcer, bay sore, forest yaws)
New World Mucocutaneous (espundia)
Cutaneous Leishmaniasis manifestations?
Furuncle like nodule which ulcerates; red raised area around the ulcer enlarges for 2-3 months, heals leaving scar
Mucocutaneous Leishmaniasis manifestations?
Produces similar lesions as the cutaneous version, but can metastasize to nasopharyngeal tissues, up to several years later and cause gross mutilations of the nose and palate.
Epidemiology of Cutaneous Leishmaniasis?
Endemic to the Mediterranean and Middle East, Asia, Africa, Central and South America (extending north to Mexico and SC Texas)
Epidemiology of Mucocutaneous Leishmaniasis?
Disease is limited to the new world. THe SANDFLY vector is infected by biting humans or animals. Outbreaks of cutaneous leishmaniasis have occurred among US military personnel operating the Middle East.
Diagnosis of Leishmaniasis?
Leishmanin Skin Test
Papule which ulcerates, giving rise to large ulcer with round paillomatous or vegatative surface. Elevated, papillomatous, crusted lesion resembling a rasberry and may enlarge to several centimeters, forming an ulcerative mass. Location: Site of inoculat
YAWS (Frambesia)
Etiology of YAWS?
Treponema pallidum pertenue
Epidemiology of Yaws?
Humid equatorial countries. Transmission-scany clothing, poor hygiene, and skin trauma
Deep destructive ulceraton (infectious necrotizing panniculitis) at the site of inoculation, usually the arms and legs.
Buruli Ulcers (Mycoburuli ulcers)
Etiology of Buruli Ulcers
Mycobacterium ulcerans...only grows below 37 degrees
Epidemiology of Buruli Ulcers?
An ulcer of the skin and underlying tissue is the sole symptom due to the temperature requirements of the organism. Common along the Nile River, also found in W. Africa, SE Asia, Australia, and Mexico. Strongly linked to the aquatic ecosystem, transmitted by water and possibly insects
Pathology of Buruli ulcers?
Polyketide mycolactone.

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