Fungus Flashcards
Systemic Mycososes
and location
- Hisplasma capsuluta: Midwestern US ( Ohio/Missippi River Valley)
- Blastomycosis dermatitis (Southern and Eastern US/ Great Lakes and Ohio River Valley)
- Coccoides immititans (Southwestern US: AZ, NM, Mexico, Cali; San Joaquin Valley) DUST
- Paracoccidioesmucoses => brazilan blastomyosis (SA and brazil)
All systemic mycoses are dimorphic. However, which is weird
Coccoides imitations
Cold: mold (25-30)
Heat (35-37): spherule of endospores. When the spherule ruptures, it releases the endospore to go throughout our body
What skin conditions do we see in coccidioes and histoplasma
erythema nodosum; but these are more common in cocciodies
Coccoides imititans can affext what in immunocompromised
skin
bone
lungs
meninges (HA and stiff neck)
dx Coccoides imititans
- KOH stain/culture
2. Seriology: IgM AB titers
what does the yeast form of Paracoccidioidomycosis look like?
how is it transmitted?
central vacoule with multiple buds that radiate out (captains wheel)
Paracoccidioidomycosis how is it transmitted?
respiratory droplets => inhaled =: LYMPHADENOPATHY (cervica => axillary and inguinal; moves down). As the disease progresses, it affects the lungs and URT, forming MUCOSAL LESIONS (ulcers in the URT and mouth)
________ and ______ lymphadenopathy are the most important defining clinical features of the Paracoccidioidomycosis.
mucocutaneous lesions and
cervical lymphadenoopathy
Which cutaneous fungus is dimorphic (only one)
Sprothrix schenkii = Sporotrichosis (Rose Gardners Dz)
All systemic mycoses can form what?
granulosum, like TB
pneunmonia
Which fungus is most often confused for TB?
Histoplasma
which fungus a clinical presentation in heathly that is similar to acute pneo: coughing, arthralgia, fever?
Coccidious imitatans
Who is more suceptible to infections in catalase + organisms?
People with chronic granumatous diseases
What two fungi are CATALASE +?
What does this imply?
- Candida albicans
- Asperigullis Fumigatus
This implies that people with chronic granulomatous disease are more susceptible
Aspergillus ______, produces AFLATOXINS, which does what?
Aspergillus FLAVUS => alflatoxins => can cause hepatocellular carcinoma
Morphology can be used to distinguish Aspergillus vs. Mucor
How?
Aspergillus have
acute branching hyphae (<45 degrees) with SEPTATIONS.
How is asperigillus transmitted?
Forms conidiophores with fruiting bodies. They sit at the top and are released into air => inhaled in humans.
3 main infections caused by aspergillus?
- Allergic Bronchopulmonary Aspergillosis (ABPA)
- Aspergillomas (fungus balls)
- Angioinvasive Aspergillosis
What is Allergic Bronchopulmonary Aspergillosis (ABPA)
Who is more susceptible?
Blood tests wil lshow what?
Type 1 hypersensitivity reaction that causes [wheezing, fever and migratory pneumo]. Assx with: asthma pts and CF;
increased IgE
Aspergillomas (fungus balls): who is more susceptible?
TB patients (those with pre-existing cavitary lesions) or Klebsiella.
Who affects immunocompromised pts wiht aspergellis?
Which immunocompromised pts are more suscpetible
Angioinvasive Aspergillosis
Those with neutropenia d/t leukemia or lymphoma.
Angioinvasive Aspergillosis invades BV and disseminates quiclkly. Thus, on imaging you can see the acute branched, septic hyphae in vessels.
What does it cause and what organs does it affect?
- Hemoptysis (bloody cough)
- Fever
Heart (endocarditis)
kidneys (renal failure
Black ring enhancing lesions in the brain.
Paranasal necrosis (necrosis around the nose)
LEss serious infections of Aconazole can be treated how?
- VORICONAZOLE
2. MUST be surgically debreded
How is cryptococcus neoformans, a oportunistic infection, different from other fungi?
- Heavily encpsulated with repeating polysaccharide antigens on the capsule; which is its main VF and makes it anti-phagocytic
- Urease +
- MOST COMMON CAUSE OF FUNGAL MENINGITIS
How do we get cryptococcus neoformans?
Who is most commonly affected?
In soil in pigeon poop => enters body via inhalation and settles in lungs => disseminates throughout the body (CSF)
HIV pts, cancer pts
Sx of cyrtococcus neoformans
- Cough/resp problems
- Fever
- Fungal meningitis, with soap bubble lesions in grey matter seen on images, which can cause DEATH
What culture is used for all FUNGI, but rarely used bc it takes so long?
Sabouraud’s agar
Dx of cryptococcus neoformans,
- Culture with Sabouraud’s agar (slow)
- Bronchopulmonary washings of lung tissue, stained with red (mucicarmine) or silver (methananime) stain
- Dx meningitis: Lumbar puncture and CSF stained with iindia ink: darkens background will organism is transparent (negative staining technique); yeast will as wide clear zone with capsular halos
- Latex agglutination test is more sensitive. It detects the repeating capsular polysaccharide antigens => causes agglutination.
- Soap bubble lesions
Tx of cryptococcus neoformans,
- Amphotericin B + Flucytosine
2. Fluconazole
what is the most COMMON CAUSE OF FUNGAL MENINGITIS?
CRYPTOCOCCUS NEOFORMAS
Pt comes in with a CD4 count below 200 and a diffuse, interstitial pneumonia and a NON-productive cough.
What does this patient have?
What will a CXR show?
- Pneumocystis jiroveci causes pneuocystis pneumonia, a opportunistic fungus that is most common in AIDS patients (CD4 count below 200).
Diffuse, interstitial pneumonia with a ground glass appearance.
In the fungus Pneumocystis jiroveci,, who can get it.
Both normal AND immunocom people, but only immunocomp will show sx.
Pneumocystis pneuomonia, is a ______-definining illness
AIDS
How do we DX Pneumocystis jiroveci?
- BAL (bronchoalveolar lavage, which rinses lungs
2. Tissue sample=> stain with Methamine silver: will appear disk/ oval)
What is BACITRACIN
A sulfa-drug prophalyxis for anyone with CD4 <200 AND to TX pneumocystis jrivocci
IF someone has a sulfa allergy, how do we treat PCP (pneumocystis pneumo)
Pentamadine
What is the MOST prevalent AIDS-defining illness
Pneumocystis jiroveci pneumonia (PCP Ping Pong)
