Fungi II Flashcards
opportunistic mycoses
-candida
-cryptococcus
-aspergillis
-mucormycosis
-pneumocystis
candidiasis - overview
*YEAST
*spectrum of infectious
*endogenous in origin (normal flora and then invades)
candidiasis - causative agent
C. albicans is most common
candidiasis - risk factors
*immunocompromised hosts
*critically ill patients (ICU)
*catheters/parenteral nutrition/GI surgery
*broad spectrum antibiotics
candidiasis - clinical syndromes
*cutaneous infections
*mucosal infections
*invasive infections (bloodstream or organs)
chronic disseminated candidiasis
*s/s: fever, RUQ pain, elevated liver enzymes
*small candida abscesses in liver
*cutaneous involvement
*primarily occurs in pts with LEUKEMIA (or other immunocompromising conditions/neutropenia)
candidiasis - diagnosis
*yeast and/or PSEUDOHYPHAE (with constrictions)
*cultures of blood
cryptococcosis - causative agent
cryptococcus neoformans
cryptococcosis - acquisition
*INHALATION of spores
*bird droppings or eucalyptus/fir trees
cryptococcosis - risk factors
*defects in T cell function:
-HIV
-high dose steroids
-transplant pts
cryptococcosis - clinical features
*primary presentation = meningitis
*sometimes pulmonary disease or cutaneous manifestations
cryptococcosis - diagnosis
-encapsulated yeast with narrow-based budding on INDIA INK
-ANTIGEN (CSF and serum) detection
aspergillosis - causative agent
A. fumigatus
aspergillosis - overview
MOLD INFECTION
*exhibit ANGIOINVASION (invade and occlude arteries)
*most common form of invasive filamentous fungal disease
aspergillosis - epidemiology
*INHALATION of spores
*risk factor = severe and prolonged neutropenia
aspergillosis - clinical features
*pneumonia
*rhinosinusitis
*CNS infection
invasive pulmonary aspergillosis (IPA)
*most severe aspergillosis infection
*rapidly progressive
*HALO-SIGN or AIR-CRESCENT SIGN on radiography
*fever, cough, pleuritic chest pain, hemoptysis
invasive aspergillosis - diagnosis
*septated hyphae with ACUTE angle branching
*aspergillus GALACTOMANNAN antigen test (serum or respiratory specimens)
mucormycosis - agents
*several species can cause
*rhizopus most common
*MOLD
mucormycosis - epidemiology/acquisition
*environmental
*INHALATION most common
mucormycosis - risk factors
*diabetes (poorly controlled, esp DKA)
*hematologic malignancy
*prolonged neutropenia
mucormycosis - clinical features
*pneumonia
*rhinosinusitis
**RHINO-ORBITAL INFECTION (really bad)
*CNS disease
*disseminated disease
mucormycosis - diagnosis
*broad, NON-SEPTATE, RIGHT-ANGLE BRANCHING hyphae
mucormycosis - management
*aggressive surgical debridement
*antifungal Rx
pneumocystosis - agent
pneumocystis jirovecii
pneumocystosis - overview
*opportunistic fungal pathogen
*primarily targets the lungs in immunocompromised hosts
pneumocystosis - acquisition
*INHALATION
pneumocystosis - clinical features
*subactue pneumonia
*fever, dyspnea, non-productive cough
*classic CXR findings = bilateral diffuse infiltrates
*elevated B-D-glucan levels in serum
pneumocystosis - diagnosis
*thick and thin walled cysts on GMS staining of respiratory secretions
*PCR or direct fluorescent antibody staining on respiratory specimens
