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Old 06-14-2011
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Skin Cool Dermatology Cases #2

1- A 22-year-old man sees a dermatologist for itchy lesions on his back and chest. The lesions have recurred frequently during the past 18 months. On examination, numerous 2- to 4-mm erythematous papulopustules are found in a follicular pattern. A yellowish material can be expressed from the lesions. The rash fluoresces yellow-green under Wood’s lamp. A potassium hydroxide examination is performed (see bottom figure). Which of the following organisms is the most likely cause of this presentation?

Cool  Dermatology Cases #2-image1.jpg
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Cool  Dermatology Cases #2-image2.jpg
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A. Pityrosporum orbiculare
B. Pseudomonas aeruginosa
C. Sarcoptes scabiei
D. Sporothrix schenckii
E. Trichophyton tonsurans


2- A 22-year-old Caucasian female college student from Minnesota returns from spring break in Florida where she spent many hours sunbathing. After sunbathing, she noticed that there were many areas over her chest, shoulders, upper arms, and neck that did not tan. She denies any associated pruritus or pain. She has been otherwise well and does not take any regular medications. Physical examination reveals well-defined, irregular, off-white macules that show coalescence. There is an overlying fine white scale when the lesions are lightly scraped. The macules are of varying size between 3 and 5 mm and bilaterally distributed in the stated areas. What is the most likely diagnosis?

A. Pityriasis versicolor
B. Psoriasis vulgaris
C. Seborrheic keratosis
D. Tinea corporis
E. Vitiligo


3-A 30–year-old man has come to the office with acute ankle swelling that began 48 hours ago. He has had this type of arthritis flare twice before and was given antibiotics for it. He is sexually active and usually uses a condom. He is in severe pain and wants to feel better. His friend gave him some ibuprofen (Motrin) and codeine, which helped alleviate the pain a little. Physical examination reveals a swollen, erythematous left ankle and right knee. He has two lesions on his hands (see figure). What laboratory test would help diagnose this man's condition?

Cool  Dermatology Cases #2-image3.jpg
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A. Ankle aspiration
B. Antinuclear antibody
C. Chlamydia smear of the urethra
D. Complement levels
E. Sedimentation rate
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Old 06-15-2011
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Default case-2 Pityriasis vesicolor

Pityriasis vesicolor

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Case-1 not too sure!

Again A - Pityrosporum orbiculare!
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Default Case-3 reactive arthritis!

I like to choose C.Chlamydia smear of the urethra.

The picture shows secondary syphilis rash in palm. Not 100% sure!
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case 1

Option A (Pityrosporum orbiculare) is correct. Pityrosporum orbiculare is the round form of the yeast previously called Malassezia furfur that is part of the normal skin flora but may overgrow with increased heat and humidity, causing this man’s condition, pityriasis versicolor (see figure). The lesions tend to be scaly, macular, uniform in color, and usually hypopigmented, but they may be hyperpigmented. A potassium hydroxide examination reveals short, rod-shaped hyphae mixed with spores in clusters (“spaghetti and meatballs”). Treatment is topical selenium sulfide or ketoconazole.

Option B (Pseudomonas aeruginosa) is incorrect. Pseudomonas aeruginosa folliculitis is a recently recognized condition resulting from exposure to contaminated water. The organism can be seen on Gram stain and cultured. Wood’s lamp would generally not fluoresce.

Option C (Sarcoptes scabiei) is incorrect. Sarcoptes scabiei is the mite that causes human scabies, a disease manifested by intense pruritus. The mites travel in the stratum corneum of the skin, especially between the digits and the groin areas, leaving characteristic burrows.

Option D (Sporothrix schenckii) is incorrect. Sporothrix schenckii causes sporotrichosis, a chronic granulomatous lymphocutaneous lesion resulting from a puncture wound inoculation of the organism. Periodic acid–Schiff stain of a granuloma sample shows cigar-shaped spores. Wood’s lamp would generally not fluoresce.

Option E (Trichophyton tonsurans) is incorrect. Trichophyton tonsurans is one species of fungus that causes tinea corporis. These dermatophytes live exclusively in the stratum corneum, hair, and nails. The potassium hydroxide examination reveals branching, rod-shaped, septate hyphae; the branching distinguishes this from Candida and tinea versicolor. Wood’s lamp would generally not fluoresce.

High-yield Hit 1
Morphology
When viewed in skin scrapings, M. furfur appears as clusters of spherical or oval, thick-walled yeastlike cells that are 3 to 8 μm in diameter (Figure 72-1). The yeast cells may be mixed with short, infrequently branched hyphae that tend to orient end to end. The yeastlike cells represent phialoconidia and show polar bud formation with a "lip" or collarette around the point of bud initiation on the parent cell (Figure 72-2). In culture on standard media containing or overlaid with olive oil, M. furfur grows as cream-to-tan yeastlike colonies composed of budding yeastlike cells; hyphae are infrequently produced.
Epidemiology
Pityriasis versicolor is a disease of healthy persons that occurs worldwide but is most prevalent in tropical and subtropical regions. Young adults are most commonly affected. M. furfur is not found as a saprophyte in nature, and pityriasis versicolor has not been documented in animals. Human infection is thought to result from the direct or indirect transfer of infected keratinous material from one person to another.
Clinical Syndromes
The lesions of pityriasis versicolor are small hypopigmented or hyperpigmented macules. The upper trunk, arms, chest, shoulders, face, and neck are most often involved, but any part of the body can be affected (Figure 72-3). The lesions are irregular, well-demarcated patches of discoloration that can be raised and covered by a fine scale. Because M. furfur tends to interfere with melanin production, lesions are hypopigmented in dark-skinned persons. In persons who are light-skinned, the lesions are pink to pale brown and become more obvious when they fail to tan after exposure to sunlight. Little or no host reaction occurs and the lesions are asymptomatic, with the exception of mild pruritus in severe cases. Infection of the hair follicles, resulting in folliculitis, perifolliculitis, and dermal abscesses, is a rare complication of this disease.
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case 2

Option A (Pityriasis versicolor) is correct. This patient most likely has pityriasis versicolor, a superficial fungal infection with Malassezia furfur (also known as Pityrosporum ovale). The name versicolor describes the lesions, as they are different colors in different seasons. In winter months, these lesions are typically slightly hyperpigmented (and thus, less noticeable) than in the summer, when they become hypopigmented. The infected areas do not tan and thus, when patients sunbathe causing their skin to tan, the contrast can be stark, resulting in presentation to the physician. The lesions typically have a fine scale that is observed best when scraped with a scalpel or glass slide. A potassium hydroxide (KOH) preparation shows hyphae and spores.

Option B (Psoriasis vulgaris) is incorrect. Psoriasis vulgaris presents with well defined, erythematous plaques that have silvery white scales at places of repeated trauma.

Option C (Seborrheic keratosis) is incorrect. Seborrheic keratosis is a benign epithelial tumor that presents as a well defined, waxy papule that has a warty surface and appears “stuck on” to the skin.

Option D (Tinea corporis) is incorrect. Tinea corporis presents with a pruritic, scaly round plaque that has an erythematous margin and central clearing.

Option E (Vitiligo) is incorrect. Vitiligo is a close differential diagnosis in patients with pityriasis versicolor. Distinguishing features are distribution (periorbital and perioral, perineum, axillae and areas of repeated trauma/pressure, such as elbows, knees, sacrum, and malleoli), absence of scale and a predilection of the areas to burn when suntanning. The lesions do not fluoresce under UV light.

High-yield Hit 1
Tinea Versicolor (PTG)
BASIC INFORMATION
DEFINITION
Tinea versicolor is a fungal infection of the skin caused by the yeast Pityrosporum orbiculare (Malassezia furfur).
SYNONYMS
ICD-9CM CODES
111.0 Tinea versicolor

Pityriasis versicolor
EPIDEMIOLOGY & DEMOGRAPHICS
Increased incidence in adolescence and young adulthood
More common during the summer (hypopigmented lesions are more evident when the skin is tanned)
PHYSICAL FINDINGS & CLINICAL PRESENTATION
Most lesions begin as multiple small, circular macules of various colors.
The macules may be darker or lighter than the surrounding normal skin and will scale with scraping.
Most frequent site of distribution is trunk.
Facial lesions are more common in children (forehead is most common facial site).
Eruption is generally of insidious onset and asymptomatic.
Lesions may be hyperpigmented in blacks.
Lesions may be inconspicuous in fair-complexioned individuals, especially during the winter.
Most patients become aware of the eruption when the involved areas do not tan (Fig. 1-240).
ETIOLOGY
The infection is caused by the lipophilic yeast P. orbiculare (round form) and P. ovale (oval form); these organisms are normal inhabitants of the skin flora; factors that favor their proliferation are pregnancy, malnutrition, immunosuppression, oral contraceptives, and excess heat and humidity.
DIAGNOSIS
DIFFERENTIAL DIAGNOSIS
Vitiligo
Pityriasis alba
Secondary syphilis
Pityriasis rosea
Seborrheic dermatitis

Figure 1-240 The classic presentation of tinea versicolor with white, oval, or circular patches on tan skin. (From Habif TB: Clinical dermatology: a color guide to diagnosis and therapy, ed 3, St Louis, 1996, Mosby.)
WORKUP
Diagnosis is based on clinical appearance; identification of hyphae and budding spores (spaghetti and meatballs appearance) with microscopy confirms diagnosis.
LABORATORY TESTS
Microscopic examination using potassium hydroxide confirms diagnosis when in doubt.
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case 3


Option D (Complement levels) is correct. This patient is showing signs of GC arthritis. Testing complement levels is important here because people with recurrent gonococcal (GC) infections, especially disseminated infections, have terminal complement deficiencies.

Option A (Ankle aspiration) is incorrect. Early in GC arthritis, the effusions are negative for organisms, so the best action is to culture the lesions. A joint aspiration would not be entirely incorrect, but it would not be that productive at this stage, especially with the other clues that this is a GC infection.

Option B (Antinuclear antibody) is incorrect. This will not help determine the diagnosis and may be falsely positive because he is infected. Antinuclear antibodies should be avoided in acute arthritis when there are no other clues of connective tissue disease because they will often be false positive.

Option C (Chlamydia smear of the urethra) is incorrect. Although Chlamydia accompanies gonococcal (GC) infection frequently, it does not cause this type of arthritis. This patient has the classic lesions of GC arthritis and should be cultured and treated for that. He may need Chlamydia treatment as well. Chlamydia is more commonly associated with reactive spondyloarthritis.

Option E (Sedimentation rate) is incorrect. The sedimentation rate will be elevated, but it is not diagnostic and will not help in treatment or diagnosis. Because the patient has inflammation clinically, there is no reason to test it serologically in this case. A C-reactive protein would not help, either.

High-yield Hit 1
BOX 30-4. Neisseriaceae: Clinical Summaries
Neisseria gonorrhoeae
Gonorrhea: Characterized by purulent discharge for involved site (e.g., urethra, cervix, epididymis, prostate, anus) after 2- to 5-day incubation period
Disseminated infections: Spread of infection from genitourinary tract through blood to skin or joints; characterized by pustular rash with erythematous base and suppurative arthritis in involved joints
Ophthalmia neonatorum: Purulent ocular infection acquired by neonate at birth
Neisseria meningitidis
Meningitis: Purulent inflammation of meninges associated with headache, meningeal signs, and fever; high mortality rate unless promptly treated with effective antibiotics
Meningococcemia: Disseminated infection characterized by thrombosis of small blood vessels and multiorgan involvement; small, petechial skin lesions coalesce into larger hemorrhagic lesions
Pneumonia: Milder form of meningococcal disease characterized by bronchopneumonia in patients with underlying pulmonary disease
Eikenella corrodens
Human bite wounds: Infection associated with traumatic (e.g., bite, fistfight injury) introduction of oral organisms into deep tissue
Subacute endocarditis: Infection of endocardium characterized by gradual onset of low grade fevers, night sweats, and chills
Kingella kingae
Subacute endocarditis: As with E. corrodens
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Quote:
Originally Posted by 1TA2B View Post
I like to choose C.Chlamydia smear of the urethra.

The picture shows secondary syphilis rash in palm. Not 100% sure!
i choose like u but it is wrong
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Thanks.

Here is hemorrhagic pustules of GC!

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Miss Patho,
In regards to case 1 u said answer is Pityriasis orbiculare (Malassezia Furfur) but the electonic microghraph shows a picture that i don't identify as that. The Malassezia Furfur has a spaghetti and meatballs appereance on light micrograph and a round ball appereance on electon micrograph..Please explain...Thanks
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Quote:
Originally Posted by aksyonez View Post
Miss Patho,
In regards to case 1 u said answer is Pityriasis orbiculare (Malassezia Furfur) but the electonic microghraph shows a picture that i don't identify as that. The Malassezia Furfur has a spaghetti and meatballs appereance on light micrograph and a round ball appereance on electon micrograph..Please explain...Thanks
KOH preparation shows filamentous hyphae and globose yeast forms, which has been termed a spaghetti and meatballs appearance.
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Default Dissiminated GC, not syphilitic rash!

Quote:
Originally Posted by 1TA2B View Post
Thanks.

Here is hemorrhagic pustules of GC! The one the case was not secondary syphilitic rash!
The one the case was not secondary syphilitic rash! Do you agree miss patho?

It actually is dissiminated GC!
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