Fungal Infections Flashcards
Candidemia TOC
Echinocandin
.
Invasive aspergillosis TOC
Voriconazole
Allergic bronchopulmonary aspergillosis TOC
Itraconazole or voriconazole
+ glucocorticoids
Aspergilloma (fungus ball) TOC
Itraconazole, voriconazole, posaconazole
Mucormycosis TOC
Liposomal amphotericin B, high-dose amphotericin B deoxycholate; posaconazole
Cryptococcal meningitis TOC
CSF findings . . .
Induction period: amphotericin B and flucytosine
Consolidation period: oral fluconazole
Maintenance period: oral fluconazole
Organ transplant may require life-long antifungal therapy.
Nonmeningeal cryptococcosis TOC
Fluconazole
Cutaneous/pulmonary/extrapulmonary Blastomycosis TOC
Lipid formulation of amphotericin B followed by itraconazole (check blood levels)
CNS Blastomycosis TOC
Lipid formulation of amphotericin B followed by fluconazole
Mild to moderate acute pulmonary Histoplasmosis TOC
Itraconazole
Moderately severe to severe pulmonary Histoplasmosis TOC
Lipid formulation of amphotericin B followed by itraconazole
Acute progressive disseminated Histoplasmosis TOC
Lipid formulation of amphotericin B followed by itraconazole
Pulmonary (patient at low risk) Coccidioidomycosis TOC
No treatment indicated
Primary pulmonary (patient at high risk) Coccidioidomycosis TOC
Itraconazole, fluconazole
Severe coccidioidal pneumonia or disseminated disease TOC
Conventional or lipid formulation of amphotericin B until improved, then itraconazole or fluconazole
Coccidioidal meningitis TOC
Fluconazole
should be lifelong
Cutaneous sporotrichosis TOC
Itraconazole
Can a negative culture exclude the diagnosis systemic candidiasis ?
N O !
How can candida present on skin?
As painless skin papules or pustules on an erythematous base
When NOT to use echinocandins
Not for those with Candida meningitis, UTI, or endophthalmitis because of poor organ penetration.
TOC for Candida parapsilosis
Fluconazole;
because C. parapsilosis may have reduced susceptibility to echinocandins.
Treatment duration for uncomplicated candidemia
14 days after clearance of the organism from the bloodstream and resolution of symptoms.
When to treat ASYMPTOMATIC candiduria
Only in neutropenic patients and those undergoing urologic procedures.
Neutropenic patients with asymptomatic candiduria should be treated similarly to those with candidemia.
Common sites for Aspergillus infection . . .
Lung being the principal site of clinical infection, followed by the paranasal sinuses.
Manifestations of pulmonary Aspergillosis . . .
Colonization,
allergic bronchopulmonary aspergillosis,
aspergilloma (fungus ball), or
invasive aspergillosis.
Cardinal features of Allergic bronchopulmonary aspergillosis
asthma-like symptoms,
fleeting pulmonary infiltrates on imaging,
peripheral eosinophilia,
elevated serum IgE levels,
serum Aspergillus-precipitating antibodies, and
cutaneous reactivity to Aspergillus antigens
When can you see an “halo sign” ?
Invasive pulmonary Aspergillosis and mucormycosis
What can impair sensitivity of β-D-glucan assay ?
Antifungal drugs and Zosyn
“Particular” risk factor for Mucormycosis ?
hematologic malignancies,
organ transplantation,
diabetes /ketoacidosis
deferoxamine for iron-overload
Outbreaks have also been reported during natural disasters.
Pathognomonic finding of rhinocerebral mucormycosis ?
presence of a black eschar on nose or palate
Mucormycosis histology . . .
broad, irregular, and ribbon-like aseptate hyphae with right-angle branching.
Predominant Crypto species in the United States?? In California?
All US: C. neoformans
California: C. gattii
Most common site of disseminated cryptococcosis
CNS
subacute or chronic meningoencephalitis.
What to do when cryptococcosis is found outside of the CNS
Lumbar puncture !!!
Skin lesions imply disseminated disease.
Check crypto Ag (serum or CSF)
sensitivity of the serum assay is lower in patients without HIV infection
Confirm w/ culture
Blastomyces dermatitidis is endemic to .
MOIST EARTH NEAR RIVER, BEAVER DAMS.
Ohio and Mississippi river valleys,
Great Lakes, and
the St. Lawrence River
MoCo site of infection for Blastomycosis ?
Primarily lungs.
Second most frequent is SKIN (painless chronic ulcer/lesion), followed by the bones, joints, and prostate.
What test should all patients with disseminated blastomycosis get
Bone scan to detect occult osteoarticular infection
What serves as nidus for infection/relapse in Blastomycosis ?
Prostate, thus get UCx
Histoplasma capsulatum is the MoCo mycosis in the US and is found in . . .
the Ohio and Mississippi river valleys.
Histoplasmosis presentation . . .
Asymptomatic,
Pulmonary Histoplasmosis (miliary lung lesions)
Disseminated disease (subacute fever, pancytopenia, hypoadrenalism, mucosal lesions- gingival ulcers)
May be seen in Histoplasmosis on peripheral blood smear
Small yeast forms within neutrophils
Check urine Ag
Coccidioides immitis and Coccidioides posadasii are endemic to . . .
Both serious lab hazards
Desert areas of the southwestern US, including Arizona, New Mexico, Texas, and the central valley of California;
Also parts of Central and South America
What is Valley fever ?
Valley fever is a subacute Coccidioidomycosis infection with respiratory symptoms, fever, and erythema nodosum.
What is “desert rheumatism,” ?
Arthralgia of multiple joints seen in Coccidioidomycosis
Risk factors for disseminated Coccidioidomycosis . . .
Immunosuppression,
AIDS, or
pregnancy
skin, bones (including vertebrae), joints, and the meninges.
Where is Sporothrix schenckii found ?
Soil, moss, and other vegetation
landscaping, gardening.
Sporotrichosis lesions
A papule appears days to weeks after
inoculation and ulcerates.
Similar lesions “spread” along lymphatics
Skin, pulmonary, osteoarticular infection
Exserohilum rostratum
Outbreak of meningitis and other infections due to contaminated lots of methylprednisolone
Treated with voriconazole
endemic mycoses = dimorphic fungi
• USA
Histoplasmosis
Coccidioidomycosis
Blastomycosis
endemic mycoses = dimorphic fungi
• Overseas
Talaromycosis marneffei (Penicilliosis marneffei)
Paracoccidioidomycosis (South American
blastomycosis)
Histoplasmosis exposure risk factor
Dust from rich earth (digging, raking) or bat guano (caving).
Coccidiodomycosis HY points
thin walled cavity may persist
chronic meningitis- Serum and CSF serology useful.
Eosinophilia in CSF.
COCCI SPHERULE BIG, NO BUDDING
Rx: fluconazole. Nonmeningeal: itraconazole
Paracoccidioides brasiliensis, HY points
Multiply budding yeast, slow growing mold.
skin and mucosal membranes
Asymptomatic infiltrates on chest xray.
-Serodiagnosis in endemic areas. Biopsy.
TALAROMYCOSIS
Talaromyces marneffei (Penicilosis)
divides by binary fission, no budding
Thailand, South China
Bamboo rats
AIDS, normal children
Skin lesions (looks like crypto [moluscum like]), lymph nodes, liver, spleen, bone
Methenamine silver stain of skin or other tissue. Blood culture+
Treatment: ampho B then itraconazole.
Other names for MUCORMYCOSIS
Hyphae invade blood vessels (like Aspergillus)
Cunninghamella,
Apophysomyces,
Saksenaea
