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Systemic Mycoses:

what form are they in the heat and cold?

What diseases do they cause?

How do you tx local infection? Systemic infection?


 All are caused by dimorphic fungi: cold (20°C) = mold; heat (37°C) = yeast.

The only exception is coccidioidomycosis, which is a spherule (not yeast) in tissue

local infection: fluconazole or itraconazole for

Systemic infection:amphotericin  

Systemic mycoses can mimic TB (granuloma formation), except, unlike TB, have no person-person transmission. 


Cave exploring, now you have a cough--> devos into pneumonaie

Smear shows Macrophage full of yeast that is smaller then RBCs

Organism responsible?

Tx if localized?

IF disseminated?

Histoplasma Capsulatum

Enter via Lung; engulfed by PMNS an Macrophages and Mulitplies rapidly in Macrophages

Localized: Fluconazole or Itraconazole

Systemic: Ampho B



Rotating in Altlanta, Pt comes in and dx with pneumonaie. 

There are broad based budding yeast seen on culture the same size as RBCs


What else can happen with this?


Blastomyces (east of Mississippi

Enters via pulmonary--> disseminates to rest of body; see Bone/skin and granulomatous disease

Tx: Fluconazole or Itraconalse if localized, Amphotericin B


You are working in a clinic in Az and there was  recent windstorm. Pt comes in with bad cough. You have seen several other pts with simular sytpoms in the past few days. You prescribe Fluconazole and send him on his way. 


What does the infectious agent responsible look like?

What about when it settles in the lungs?


Coccidiodies immitis: .West US: California and Arizona: ↑after sand storm and earthquakes

Dimorphic: has mycelial (soil) and spherule form ---> goes to Arthroconidia that become airborne and enter lung

IN lung-->  forms spherule full of endospores = LARGER then rbcs



What fungal infection can cause severe pneumonaie and has potential to disseminate to meninges, skin, bones and joints. 

Often person presents with arthralgias and erythema nodosum. 


Where would you see this?

Coccidiodies immitis

seen in S.west or Californai/Arizona

This is systemic, treat with Amphotericin B


Your friend is returning from Brazil and has had a terrible cough for several weeks. You tell her to get looked at but states she'll be fine. The next week she has granular lesions on her arms and really bad mouth sore. She went to the doctor and had the sore cultured (see below)


How does this cause disease?


Paracoccidiodes brasilliensis

Enters lungs--> disseminated progresseive disease: severe pneumoa with granulomatous change in skin and mucous membranes

Dimorphic, in Brazil with Captain Wheels appearance


You husband comes how with a beautiful boquet of roses... sigh. He said he picked them himself...sigh. A few days later you notice a pustule on his arm, you apply neosporin and bandage it. Days later he had a creeping pattern of nodules and bumps up the same arm. 



Sprothrix schenckii

Tx: Itraconazole, Potassium Iodide (put a rose in a POT)

(Dimporphic fungus in Soil and vegetation→ think roses & thorns or moss people that are gardening)


YOu are outside with your friends and notice one of your buddies has light spots along his back. You ask if they itch and he states a little but not much , just says that thinks he tans funny. 

What funal infection is this?

What does it look like in culture?

How do you dx it? Tx is?

Tinea Versicolor

Malassezia furfur: causes pigmentation on proximal tunk and limbs as round macuales and may be pruritic

Dx: KOH scrapping with spaghetti + meatball appearances

Tx: topica azole or Topical selenium sulfide



AIDS pt comes to office with complaints of sore throat when swallowing. It feels like there is pressure on his chest and it hurts. You perform an endoscopy and this is what you see. 





Candidal esophagitis:

Use Fluconazole or Capsofungin for esophagitis


Candida vulvovaginitis= severe itch/edema/vaginal discharge and seen in _____environment: seen more in diabetics, pts or women with recent antitiotics or diaper rash and have satellite lesions lesions—pustular; outside of rash



Nystatin or Clotimazole or PO Fluconozole


You suspect your pt with a central line has a systemic Candida infection

How can you dx this?

How do you tx it?

Dx: if in blood: you can blood culture it and you will see GERM TUBES = small projections on side of cell

Tx: Fluconazole or Ampho B


People with Chronic granulmatous disease or are Immunocompromised are very susceptible to this fungal infection. 

People with Asthma and CF can get this fungal infection as well.

What is the fungus?

What different diseaes does it cause in all these peole?

What does it look like?

Aspergillus Fumigatus (mold)

Invasive aspergillosis, especially in immunocompromised and those with chronic granulomatous disease.

Allergic bronchopulmonary aspergillosis (ABPA): associated with asthma and cystic fibrosis; may cause bronchiectasis and eosinophilia.

culture and see narrow septate hyphae that branch at ACUTE 45 degree angle

Tx: Voriconazole, lipid formation of Amphotericin B



What cancer is Aspergillus fumigatus associated with

Can make aflotoxins--> Hepatocellular cancer


You are working in-pt and one of the people on your floor has meningitis. Imaging shows a multple lesions. He was visiting new york and spent a lot of time shlepping through the park and streets to get to different events. 

Latex agglutination test detects polysaccahride capsular antigen. 


What special stain can you use on this organism?

How do we tx this pt?

Cryptococcus Neoformans

Dx. INDIA INK: stains polysaccharide capsule or serological test for cyrptococal antigen or Latex agglutination test to find polysaccharide capsular antigen  OR  image of Soap Bubble lesion in brain

Cryptococcal meningitis: seen in AIDS pts

Tx: Amphotericin B + Flucytosine followed by fluconazole


Heavily encapsulated yeast, Narrow-based budding, foudn in PIGEON shit and causes meningitis in Aids pts.

What else can we culture it on beside bacterial and fungal media?

Cryptococcus Neoformans

INDIA INK and Sabourauds agar


Broad, irregular shaped nonseptate hyphae branching at right angles: it is Ubiquitous in the environment

It is invaise in immunocompromised, diabetics, trauma pts

Mucor and Rhizopus


Pt is undergoing chemotherapy and complains of horrible headache and pain along her forehead and eyebrow. It is not dt any of her mediations. 

If you were to biopsy the vessels in the affected area you would see large necrotic lesions. 

What's the cause?

What other pt population is susceptible to this?

Waht is the T?

Rhinocerebral mucormycosis

facial pain + headache bc orgnamis grows into blood vessel walls: see large necrotic lesions; may involve eye or brain

Seen in: in dibetics (DKA) and leukemia 

Tx: surgical debridemnt and amphotericin B


Diffuse interstitial pneumonia with ground glass apperance--> atypical or walking pneumonia that progresses to fatal pneumo in immunocompromised pts : often put BMT pts and AIDS pts on prophylaxisis for this

Whats the pathogen?

When do AIDS pts get proph for this and what prophy do they get?

What does this stain with?

Pneumocystis Jirovecci (PCP)

Start PCP prophy of CD4 TMP-SMX

Tx:  TMP-SMX (Bactrim) start with IV--> go to oral

Silver STain


Trichopyton, Microsporum: from dog or cat-->  human, Epidermophyton, Malassezia furfur

Cause; tinea pedis (feet), Tinea Cruris (groin), Tinea Corporis (body), Tinea Capitis (head) and Tinea on head or foot = ring worm and see clearing from dermatophyte infection

Dx: fungal hyphae or spores on skin or hair samples or send to lab to culture

Tx for simple cutaneous?

for Extensive?

Simple cutaneous: use Topial Terbinafine or azole vs 

Extenxive skin/scalp tx with Oral terbinafine or Azole


Hikers/campers drinking from stream: beaver fever diarrhea and FOUL diarrhea

Wet mount shown below


How do we get this disease?

How it is tx?

Giardia Lamblia

ngested cysts--> trophozoites that ≠fat absorption = acute, fatty, foul smelling diarrhea, flatulence

Tx: Metronidazole


Pt comes in with bloody diarrhea and RUQ pain. Imaging shows an Abcess on the liver. 

You collect a stool sample and make a dx. 


What was in the stool sample?

What's with the liver invovlement?


Entameoba histolytica

Dx: trophozoites or cysts in stools and often have ingested RBC with multiple nuclie or dx via Serology (look for antiB vs amoeba)

Colon + Liver; invades and destroys the colon--> can perforate it and cause LIVER ABCESS with RUQ pain and Flask shaped ulcer

Tx: Metronidazole + Tinidzole to kill trophozoites then use Iodoquinol and Paromyocin to kill cyst


AIDS pts with chronic watery diarrhea. 

Dx: Ooctyes on acid fast stain of stool

What does this pt have?

How is it transmitted?


oocyts in water or person-person spread but filtration removes them


Newborn baby has Hydrocephalus. You perform a CT and get the results shown below and see intracranial calcificaitons

What is teh Dx?

What is another thing typically seen in newborns with this disease?

How did the baby get this disease and what could ahve been done to prevent it?

Toxoplasma Gondii

Triad: Chrioretinitis, hydrocephalus, intracranial calcifications

Trasnmission from infected mom transplacentally (pregnant women + cats)

T: Sulfadiazine + Pyrimethamine


Aids pt comes in with focal neurological deficiets. You get CT and see multilpe ring enhancing lesions. Dx?



 Toxoplasma gondii

 oocytes in cat feces or  cysts in infected meat


You are boating with your friend on a lake and a few days later have a stiff neck, headache and sensitivity to light. You are concerned you have a deadly pathogen that most likely snuck it's way in thorugh your cribiform plate and rush to the hospital for tx. 

You are saved by what medication from what dealdy bug?

Naegleria fowleri

Amphotericin B (most die)

Amoeba causing fatal meningoencephalitis transmission from Freshwater lakes


A man from Africa comes to your clinic. He has enlarged lymph nodes and is very tired.  with recurring fever. You send him home with instructions to sleep and get plenty of fluids (you think this is viral) He ends up in the ER a week later after he lapsed into a coma and dies from enchephalitis. 

What Dx did you miss and how should you have treated the pt?

Trypanosoma Brucei

Rhodesiense or Gambeinse = African sleeping sickness

Transmisted through tsetse fly(painful bite) and get into blood stream

Tx: Sumarin for blood borne and Melarosporl for CNS


Mother and her daughter are immagrants from Africa and are here bc the daughter feels very tired. She has conjunctival pallor and splenomegaly. She explains that she occasionaly gets a fever on and off for a day, then it goes away and thats usually when she feels tired. 

What is the vector resonspible for this disease?

What is the disease?

What will you see on blood smear?

What do you tx her with?

Vector= Anopheles mosquito

Has Malaria, specifically Plasmodium Vivax or Ovale (48 hours cycle)

Blood smear: Trohpozoite ring that forms withing RBC or a Schizont containing merozoites

Tx: Chloroquine and add Primaquine for the formant stage seen in Vivax and Ovale to kill the hypnozoite


Before starting a pt dx with P.Vivax  or P.ovale on Primarqine to kill the Hypnozoite, what do you need to test them for?

G6PD deficiency!


Pt from Africa has relapsing and irregular fevers. She is anemic, has elevated Creatinine and blood sugars are 40. During her workup she has a seizure and relapses into a coma about an hour later and dies. Peripheral blood smear is shown below. 



P.Falciparum; malaria

Causes severe; irregular fever patterns; parasitized RBCs occlude capillaries in brain (cerebral malaria), kidneys, lungs 

Smear: Gametocyte form = banana shape! Goes with Plasmodium Falciparum


What is the life cycle of malaria?


1. sporozoites from mosquito enter the bloodstream, and migrate to the liver.

2.infect liver cells, where they multiply into merozoites, rupture the liver cells, and return to the bloodstream.

3. The merozoites infect RBCs, where they develop into ring forms= trophozoites and schizonts that in turn produce further merozoites. 

4. Sexual forms are also produced, which, if taken up by a mosquito, will infect the insect and continue the life cycle.