Mycology Flashcards
Aspergillus fumigatus
- MCC of non-candidal invasive fungal infection post-transplant & other immunosuppressed patients
- affects lungs, sinuses, brain
- directly invades the tissue and causes damages OR creates an immunological reaction
Aspergillosis clinical manifestations
- chest pain
- pneumonia
- sputum with blood
- vision difficulties
- HAs
- anorexia
- hematuria
Allergic Bronchopulmonary Aspergillosis (ABPA)
- occur in patients with chronic lung diseases such as asthma or cystic fibrosis
- bronchospastic exacerbations with fleeting pulmonary infiltrates with eosinophilia, high levels of IgE, and IgG Aspergillus precipitins in the blood
- sinusitis with chronic inflammation with eosinophilic mucus and noninvasive hyphal elements
Chronic aspergillosis
- Spectrum of disease most commonly noted in chronic lung disease but without immunocompromised state
- Ranges from aspergillomas (causing lung cavitations) to chronic fibrosing pulmonary aspergillosis (pulmonary parenchyma replaced with fibrosis)
- Pneumonia like presentation without a response to ABX
Ring enhancing lesion on lung CT
Aspergillosis
Invasive Aspergillosis
- MC in severely immunodeficient pts.
- Pulmonary disease is MC with patchy infiltration progressing to severe necrotizing pneumonia
- disseminates through blood to brain, skin, heart, and other organs
Definitive Dx of aspergillus
Bx of tissue/culture from a sterile site with Aspergillus
CT finding of halo sign
invasive aspergillosis
Post organ transplant with a halo sign on CT
aspergillosis
immunosuppressed pt. with fever, hemoptysis, pleuritic chest pain
CXR shows a cavitary lesion of a rim of ground glass attenuation surrounding a pulmonary nodule
Aspergillosis
Blastomycosis
- dimorphic fungus (yeast in the body)
- MC in men of occupational/recreational activities outdoors
- afflicts domestic cats/dogs
Blastomycosis location
South central and MW US and Canada
Traveler from Ohio, Mississippi, Great lakes regions
Blastomycosis
Clinical manifestations of blastomycosis - pulmonary infection
- MC form of dz is pulmonary infection
- mediastinal lymphadenopathy with purulent cough, pleurisy, fever, weight loss
CXR of Blastomycosis
nodules, granulomas, mediastinal LAD, cavitary lesions (mimics TB)
Disseminated (gets into the blood) infection of Blastomycosis
- spread is not uncommon
- osteomyelitis, GU lesions, CNS lesions
Dx testing of blastomycosis
fungal cx is gold standard
Coccidioidomycosis AKA
San Joaquin Valley fever
Blastomycosis management of mild to moderate disease
itraconazole
severe disease is amphotericin B to start and then itraconazole (oral)
Coccidioidomycosis geographic region
AZ/CA
desert regions of western hemisphere
Coccidioidomycosis spread
via inhalation of molds dispersed with disturbed soil
Disturbed soil
dust storm
vigorous hiking
heavy rainstorms
construction
Coccidioidomycosis
Coccidioidomycosis clinical manifestations of primary Coccidioidomycosis
erythema nodosum rash, fever, chills, fatigue, chest pain, cough, SOB, migratory arthralgia
usually self-limiting after several weeks
Coccidioidomycosis disseminated cases
- more severe disease in immunocompromised
- chronic infection in about 5% of cases
- disseminated dz to meningeal, bone, joint spaces, pericardium, skin
- meningitis in 30-50% of disseminated cases
Desert Rheumatism Triad of Coccidioidomycosis
arthralgia
fever
erythema nodosum
Coccidioidomycosis CXR findings
- associated with chronic dz
- mediastinal LAD
- nodules
- granulomas
- cavitary lesions
- spontaneous pneumothorax
Coccidioidomycosis when to treat
- weight loss >10%
- night sweats for >3wks
- significant pulmonary infiltrates
- prominent hilar LAD
- titers >1:16
- inability to work
- Sx lasting >2months
pigeon poop
cryptococcosis
cryptococcosis distribution
Pacific West Coast: WA, OR, CA
Where is cryptococcosis found
in soil and dried pigeon poop
cryptococcosis clinical manifestations
- usually asx in immunocompetent individuals
- disseminates to organs and CNS the worst
- HA is first manifestation of meningitis
- nuchal rigidity
- meningeal signs
- communicating hydrocephalus (ventricles in the brain get clogged and CSF cannot circulate)
- bacterial-like cellulitis
Immune reconstitution inflammatory syndrome (IRIS)
patient gets worse despite improved immune status in cryptococcosis
Dx of cryptococcosis
- india ink stain of CSF
- cryptococcal capsular antigen in CSF and Cx together: Dx in >90% of cases
cryptococcosis tx
- liposomal amphotericin B preferred initial medication followed with oral fluconazole
When it is ok to switch from amphotericin B to oral fluconazole for cryptococcosis tx
- favorable clinical response (improve in any way)
- improvement in CSF biochemical profile
- conversion of CSF cx to negative
failure to recognize and correct high intracranial pressure in cryptococcosis
leads to increased morbidity and mortality
Histoplasmosis locations
OH
Mississippi river valley areas
found in soil with bird/bat guano
Spelunking and excavation
Histoplasmosis
Histoplasmosis v. Blastomycosis (as both in the same area)
Histoplasmosis is caves/spelunking with bat/bird poop
Blastomycosis is with individuals that work in construction outside
Histoplasmosis clinical manifestations
inhale the mold and converts to yeast in lungs
spreads to lymph nodes and liver/spleen
Acute primary pulmonary histoplasmosis: clinical manifestations
Most ASx and almost never fatal
- prodome like and also have HSM, acute pancreatitis, arthralgias, erythema mulitforme/nodosum
Chronic pulmonary histoplasmosis: clinical manifestations and CXR
- Hematemesis
- most with cavitary lesions have COPD/chronic bronchitis that masks the underlying fungal disease
- CXR: mediatstinal LAD, apical cavities
Progressive disseminated histoplasmosis: risk factors
- AIDS
- extremes of age
- immunosuprressive meds
- MTX
- Meds for inflammatory - arthritis or Chron’s
Progressive disseminated histoplasmosis clinical manifestations (incl. CXR)
- fulminant dz resulting in pulmonary, renal, coagulation complications
- CXR: miliary pattern
- CNS: meningitis or focal brain lesions
- oral mucosal ulcerations
- HSM
- adrenal insufficiency
- GI involvment
Histoplasmoma
healed area of caseation necrosis surrounded by a fibrous capsule on CXR
Mediastinal fibrosis of Histoplasmosis
- rare consequence of a fibroblastic process that encases caseating mediastinal lymph nodes after primary histoplasma bronchopneumonia
- Constriction of the bronchi results and bronchiectasis, also esophageal stenosis associated with dysphagia, and superior vena cava syndrome
- Progressive fibrosis producing severe retraction, compression, and distortion of mediastinal structures
Presumed ocular histoplasmosis syndrome
- atrophic choroidal scars and maculopathy
- distortion or loss of central vision without pain, redness, or photophobia
Mucormycosis: Rhinocerebral disease
- MC form
- Fever, headache, unilateral facial swelling/pain/numbness, sinus congestion, and unilateral blindness
- Necrosis is common due to hyphal tissue invasion manifest as ulcerations of the hard palate or nasal plate or hemoptysis
Mucormycosis Pulmonary disease
Very similar presentation as invasive pulmonary aspergillosis; differentiated by concomitant rhinocerebral symptoms
Mucormycosis Cutaneous disease
- Starts as area of erythema that develops into a black eschar
- Necrotizing fasciitis is possible due to angioinfective properties of the fungi
Mucormycosis Disseminated disease
- Organ specific manifestations
- CNS findings of altered mental status and coma
Halo vs. reverse halo
Halo: aspergillosis
Reverse halo: mycormycosis
Sporotrichosis
Rose gardener’s disease
Rose gardener’s disease
Sporotrichosis
Sporotrichosis is commonly found where
in or on soil, hay, peat moss, plants, and rose thorns
- cats carry on paws and spread via scratching
Rose garden and stuck by a thorn
Sporotrichosis
Sporotrichosis clinical manifestations of cutaneous
- MC form of the infection
- Starts with hard, non-tender subcutaneous nodules
- Develop lesions adherent to overlying skin that then ulcerate
- Occurs on fingers, hand, or arm (where inoculated)
- Lymphocutaneous disease occurs as infection spreads up lymphatic channels with development of secondary lesions and subsequent ulcerations
Sporotrichosis pulmonary form
- rare, occurs in people who inhale spores
- tends to occur in people with preexisting lung dz
Sporotrichosis: Disseminated sporotrichosis
- affects cats/dogs
- occur via hematogenous spread
- joints
- lungs
- CNS
Sporotrichosis diagnostic testing
- fungal cx is gold standard
- Pathologic exam of biopsied lesions:
- Pyogranulomatous response
- Classic “cigar body” shaped yeast
Sporotrichosis is a ____ fungus
dimorphic: mold and yeast
