Chapter 162- Deep fungal infections Flashcards
Sporadic diseases contracted in the tropics, subtropics caused by fungi that have been introduced directly into dermis or subcutaneous tissue
Subcutaneous mycoses
Etiology of Sporotrichosis (5)
S. Schenkii S. Brasiliensis S. Globosa S. Lurieie S. Mexicana
One impt characteristic of sporotrichosis
Scarcity of organisms in tissue
Asteroid body
More common forms of sporotrichosis
Lymphangitic form
Patients with AIDS who develop sporotrichosis often who have multiple cutaneous lesions with prominent lymphatic involvement.
True or False
False, without
Molds should be confirmed to yeast phase on enriched media at 37 C
Brain heart infusion agar
Sporotrichosis may resolve spontaneously but persist for more than ___ years
3
Treatment for Sporotrichosis (2)
Itraconazole 200 mg daily
Terbinafine 250 mg daily
KI 4-6 ml TID for 3-4 weeks
Infection of chest wall is most characteristic of
Nocardia infection
Key to establishing diagnosis of mycetoma
Grains
Black grains are always caused by ___; Red grains are always caused by ___
Fungi
Actinomycetes
Matching type
- Pale white to yellow grains
- Yellow to brown grains
- Red to pink grains
A. Streptomyces brasiliensis
B. Actinomadura pelletieri
C. Actinomadura madurae
D. Nocardia brasiliensis
C D
A
B
Treatment for Eumycetoma
Itraconazole 200 mg
Ketoconazole 200mg
Voriconazole 200- 400 mg
Actinomycetoma is treated with
Dapsone + Streptomycin
TMP-SMX + Rifampin / streptomycin
Definitive treatment for mycetoma
Surgery
Used in recalcitrant Nocardia infections
Amikacin
Moxifloxacin
Imipenem
Chronic fungal infection caused by pigmented (dematiaceous) fungi implanted into dermis
Chromoblastomycosis
In chromobalstomycosis, they form thick walled single cells or cell clusters termed as ___ with paeudoepitheliomatous hyperplasia
Sclerotic or muriform bodies
Etiologic agent of chromoblastomycosis
Philaophora verrucosa Fonsacea pedrosoi Fonsacea compactm Cladophialophora carrionii Wangiella dermatitidis
Treatment for chromoblastomycosis
Itraconazole 200 mg daily
Terbinafine 250mg daily
If extensive,
IV amphotericin B 1mkday
Etiology for phaeohyohomycosis
Exophiala jeanselmei
Wangiella dermatitidis
Appear in immunosuppressed patients as short, irregular pigmented hyphae
Phaeohyohomycosis
Cystic lesions casued by nonpigmented hyphae
Hyalohyphomycotic cysts
Etiologic agent by lobomycosis
Lacazia loboi
Treatment for lobomycosis
Surgical removal
SubQ mucormycosis characterized by woody cellulitis at limb girdle sites is caused by
Basidiobolus ranarum
Subq mucormycosis present in the inferior turbinates of nose with painless swelling of central part of the face with severe deformity is caused by
Conidiobolus coronatus
Treatment for subQ mucormycosis
Ketoconazole 400 mg daily
Itraconazole 100-200mg daily
KI 4-6 drops TID
Development of polyps affecting mucous membranes esp nasal mucosa
Rhinosporidiosis
Rhinosporidiosis is characterized by development of polyps studded with white flecks called
Sporangia
2 main varietis of endemic mycoses
Opportunistic mycoses
Endemic respiratory mycoses
Erythema nodosum may be caused by
Endemic mycoses
Sexual state of Histoplasma capsulatum
Ajellomyces capsulatus
Matching type
- Biologic therapy
- DM
- Heart valve surgery
- Abdominal surgery
A. Candidiasis
B. Endemic mycosis
C. Mucormycosis
B
C
A
A
Neutropenic patients are predisposed to (3)
Aspergillosis
Candidiasis (Oropharyngeal, Systemic)
Mucormycosis
Patients with CD4 lymphopenia (3)
Candidiasis (oropharyngeal)
Cryptococcosis
Endemic respiratory mycoses
This type of histoplasmosis is more common in HIV positive patients with widespread dissemination to liver, spleen, lymphoreticular system, and bone marrow
Acute progressive disseminated histoplasmosis
The most common presentation of chronic progressive disseminated histoplasmosis are (3)
Oral or pharyngeal ulceration
Hepatosplenomegaly
Adrenal insufficiency
T. Marneffei is differentiated from Histoplasma by its
Septum formation
Intradermal histoplasmin skin test is not useful as disseminated histoplasmosis is often negative.
True or False
True
Rising complement fixation antibodies in histoplasmosis indicates
Dissemination
Precipitins by immunodiffusion are valuable due to presence of (2) antibodies
H- active infection
M- recent infection
MC involved sites of African Histoplasmosis
Skin, bone»_space; lymph nodes
African Histoplasmosis is caused by
Histoplasma capsulatum var. duboisii
Disseminated or localized histoplasmosis is treated with
Itraconazole 200-400mg daily
Blastomyces is a chronic mycosis caused by the dimorphic pathogen of
Blastomyces dermatitidis
Chief site of involvement of blastomycosis are
Lungs
Common presenting feature of disseminated blastomycosis
Skin manifestations
Hyperkeratotic, symmetric, affects face and extremities
Exposed to a cave, and presented with cough, chest pain, fever with accompanying joint pains and rash - toxic erythema, EN, or EM
Acute Pulmonary Histoplasmosis
Precipitating antibodies are present in the sera of infected patients, and a characteritic precipitin line
E band
Aside from Itraconazole, treatment for blastomycosis
Voriconazole for 6 months
Characteristic of coccidioidomycosis is a large spore containing structures in infected tissue in coccidioidomycosis
Spherules
Matching type
- Nodule or indurated ulcer
- Chancre
- Indurated nodule
- Acneiform pustules
- Echthyma Gangrenosum
- Target like lesions
A. Blastomycosis B. Coccidiodomycosis C. Histoplasmosis D. Aspergillosis E. Cryptococcosis F. Fusarium
C A B E D
Most common clinical type of coccidiodomycosis
Primary pulmonary form
Precipitins develop in approximately 90% within ___ in coccidiodomycosis
2-6 weeks
Characteristic of more severe infections and increases to a maximum in 6 months
Complement fixing antibodies
Types of coccidioidomycosis with better prognosis
Skin and joint
Dimorphic fungus with respiratory tract infection with tendency to disseminate to mucous membranes and lymph nodes
Para coccidioidomycosis
Para coccidioidomycosis mainly affects males due to presence of ___ on the fungus wherein ___ suppresses concersion of mycelium to yeast
Cytoplasmic estrogen receptor
Estradiol
Numbers of round yeasts with a characteristic form of multiple budding
Para coccidioidomycosis
(2) antibodies are highly specific for this infection in immunoblotting
Pb27
87kDa
Natural infections are known to occur in ___
Cannonys bamboo rats
T. Marneffei is a green or grayish mold that produces typical ___
Conidiophores
The most common clinical manifestation of cryptococcosis
Meningoencephalitis
Cryptococcosis are observed by direct microscopy of ___
India ink
Nigrosin
The most frequently used drug regimen in the nonAIDS patients
IV Amphotericin B + Flucytosine
In systemic candidiasis, skin lesions can occur in (2)
Neutropenic patients
IV drug users
Cause disease in patients with poorly controlled DM, neutropenia, or renal disease
Mucormycosis
Mucormycosis in close apposition of skin with contaminated dressings is caused by
Rhizopus rhizopodiformis
Mucormycosis in wooden tongue depressors
Rhizopus microsporus
Aspergillosis can be detected by using
Galactomannan assays