Systemic Last Flashcards
• A chronic granulomatous disease that characteristically produces a primary pulmonary infection (often inapparent) & then disseminates to form ulcerative granulomata of the buccal, nasal and occasionally the gastrointestinal mucosa.
PARACOCCIDIOIDOMYCOSIS
PARACOCCIDIOIDOMYCOSIS
• Etiologic agents:_____, 1971 (Adolpho Lutz, Sao Paulo, Brazil, 1908);_____,_____,_____,______
Paracoccidicides brasiliensis sensu stricto
P. lutzii (2014)
P. americano
P. restrepiensis
P. venezuelensis (cryptic species)
• Restricted to areas of South and Central America (Latin)
• Rarely isolated from nature, natural habitat not definitively determined; not communicable
PARACOCCIDIOIDOMYCOSIS
Also known as “Brazilian blastomycosis” this disease is caused by the fungus, ______ or ____
PARACOCCIDIOIDOMYCOSIS
Paracoccidioides brasiliensis or Paracoccidioides lutzii.
A neglected tropical disease
10-30 new cases/million inhabitants/year
PARACOCCIDIOIDOMYCOSIS
Paracoccidioidin skin test surveys have been conducted, but may cross-react with (2)
coccidioidin or histoplasmin
Pathogenesis and Clinical Findings
• Inhaled conidia–initial lesions in the lung-dormancy (for decades)-active pulmonary granuloma–chronic, progressive or disseminated disease
• Chronic: spread to skin/mucocutaneous tissue, lymph nodes, spleen, liver, adrenals, other sites (sores in the oral mucosa, mulberry-like stomatitis - yeasts in giant cells)
PARACOCCIDIOIDOMYCOSIS
Pathogenesis and Clinical Findings
• Susceptible - 30-60 years old, over 90% men
• 10%, less than 30 years old - acute/subacute progressive infection, shorter incubation time.
PARACOCCIDIOIDOMYCOSIS
Direct Microscopy:
• KOH or calcofluor white on sputum, exudates from lesions
• May reveal 30-40 utm, double-contoured wall, single/multiple buds/exosporulations,
“helm-like” aspect is pathognomonic for P. braziliensis;
“Mickey Mouse” aspect - very suggestive
PARACOCCIDIOIDOMYCOSIS
Serology:
• Diagnostic or prognostic value
CF, ID, EIA, WB
• Antigen: 43-kDa gp43 - the main exocellular antiger secreted by Pb yeasts
PILOTs wheel
Mariner’s wheel
Mickey mouse yeasts
Paracoccidioidomycosis.
Morphology & Identification
• Culture:
• Mold at 22C: very slow growth (up to 30 days),
flat, glabrous-leathery,
wrinkled-folded, floccose-
velvety, pink-beige-brown,
yellowish-brown reverse
PARACOCCIDIOIDOMYCOSIS
.
Morphology & Identification
Culture:
• septate hyphae, produce
chlamydospores and small (2-10 um in diameter,
one-celled conidia (features not distinctive, indistinguishable from B. dermatitidis mold phase or the microconidia of H. capsulatum )
PARACOCCIDIOIDOMYCOSIS
Morphology & Identification
• Confirm at 36C, Fava-Netto agar, enriched SDA
(+150mg/L chloramphenicol):
• large multiple budding yeast cells (up to 30 um), larger but thinner walls than B. dermatitidis
• buds are attached by a narrow connection
PARACOCCIDIOIDOMYCOSIS
• An infection caused by the dimorphic fungus,_______
• Capponi & Sureau **isolated Tm from Chinese bamboo rats ** (Rhizomys sinensis) with fatal disseminated infection at the Institute Pasteur de Dalat in Vietnam (1955-56)
Talaromycosis (Penicilliosis)
Talaromyces (Penicillium) marneffei (Tm)
• Prof. Gabriel Segretain described it after an accidental finger prick with a needle containing the yeast cells of the fungus, named it as a new species,_____ , in honor of Hubert marneffei (Director of the Institute in Indochina), renamed in 2015
• Affects people who live in or visit Southeast Asia (Thailand, Vietnam, Myanmar), East Asia (southern China, Hong Kong, Taiwan), and north-eastern India
Penicillium marneffei
Talaromycosis (Penicilliosis)
• Major risks: advanced HIV-AIDS (CD4 cell count <200cells/m°), tuberculosis, corticosteroid treatment, or lymphoproliferative diseases
Talaromycosis (Penicilliosis)
• Clinical findings: fungemia, skin lesions, systemic involvement of multiple organs (RES)
• Early signs include cough, fever, fatigue, weight loss, general discomfort, lymphadenopathy, diarrhea, & abdominal pain.
• Patients (70%), with or without AIDS, develop Small, painless papules (dent in the cutaneous/subcutaneous papules/rashes, often on the face.
Talaromycosis (Penicilliosis)
MOT: Traumatic implantation ; enteric spread following eating of bamboo rats as “game cuisine” ; inhalation of spores from soil (bamboo rat burrows) or possibly specific host plants
Talaromycosis (Penicilliosis)
• With HIV, Tm more disseminated; first reported case in 1989 from Bangkok
• Without HIV, first isolated from the spleen of patient with Hodgkin’s disease in 1973; Im more common in the mouth, throat, lungs, liver and bones. Lesions smoother without indentation.
• 2022 report: 288,000 cases in 34 countries, estimated 3.6% pooled prevalence; high case-fatality rate a third of diagnosed individuals, leading cause of HiV-associated death surpassing mortality attributable to tuberculosis and cryptococcal meningitis
Talaromycosis (Penicilliosis)
Laboratory Diagnosis
• Direct microscopy and culture of infected tissues (skin lesions, bone marrow, blood, and lymph nodes
• Tissue biopsy, touch smear (GMS, Giemsa): typical septate yeast-like cells, oval-cylindric (2-6 um), may have a cross-wall, divides by fission rather than budding,
intracellular, resemble histoplasmosis
Talaromycosis (Penicilliosis)
• Culture: mold form, rapid growth (4-7 days), green-yellow colony with a diffusible reddish pigment, sparse green aerial and reddish-brown vegetative hyphae, with red-diffusible pigment
• PCR Tests for ID confirmation.
Talaromycosis (Penicilliosis)
Morphology & Identification
• Microscopic: septate, branching hyphae, conidiophores bearing phialides and basipetal chains of conidia.
Talaromycosis (Penicilliosis)
• A systemic mycosis by a novel dimorphic fungus Emergomyces
(2017) species observed among immunocompromised individuals; fatal disseminated mycosis
•________ (widespread),_____(most endemic in South Africa),______,______,______
Emergomyces pasteurianus
E. africanus
E. canadensis
E. orientalis
E. europaeus
Emergomycosis (Emmonsiosis)
• Global emergence: Asia, Europe, Africa and North America
• Formerly under the genus Emmonsia
Emergomycosis (Emmonsiosis)
• Gold standard for identification: sequencing ITS DNA
• A mimicking fungus: disseminated cases misidentified as histoplasmosis (among those with advanced HIV disease); pulmonary form misdiagnosed as tuberculosis
• E. africanus DNA isolated from soil samples & air samples
Emergomycosis (Emmonsiosis)
• MOT: Presumed through inhalation of conidia in soil, followed by in vivo transformation to a yeast-like phase capable to extrapulmonary dissemination in susceptible hosts
• 96% disseminated disease had cutaneous lesions - umbilicated papules, nodules, ulcers, verrucous lesions, crusted plaques, and erythema
Emergomycosis (Emmonsiosis)
• Histopathology: indistinguishable from histoplasmosis
• Must use H&E, PAS, GMS to demonstrate intracellular yeasts
Emergomycosis (Emmonsiosis)
• In tissues: chronic granulomatous/suppurative infiltrates of histiocytes, multinucleated giant cells, plasma cells with intracytoplasmic narrow-based budding yeasts, 2-5 um
Emergomycosis (Emmonsiosis)
LABORATORY DIAGNOSIS
• Culture: SDA at 25C, mycelia after 14 days, white to tan (2a), glabrous to powdery to slightly raised, furrowed with age;(2b) reverse ochraceous-buff to warm buff peripherally;
Emergomycosis (Emmonsiosis)
• (2c) LPCB - “florets” of smooth-walled subglobose conidia borne on slender conidiophores, slightly swollen tip, arising at right angles from thin-walled hyaline hyphae,
Emergomycosis (Emmonsiosis)
• (2d) yeast phase on BHIA, pasty cerebriform yellowish-tan colonies after 2-3 weeks at 37C,
Emergomycosis (Emmonsiosis)
• (2e) Gram stain - round to oval yeast cells with narrow based budding
