Mycology and Helminths Flashcards
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; e_ngulfed 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
Dx?
What else can happen with this?
Tx?
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.
Dx?
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.
Tx?
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)
Dx?
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.
Dx?
Tx?
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.
Dx?
Tx?
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
Tx?
ACIDIC
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.
Dx?
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
Dx?
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.
Dx?
What was in the stool sample?
What’s with the liver invovlement?
Tx?
Entameoba histolytica
Dx: t_rophozoites 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
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?
Transission?
Toxoplasma gondii
oocytes in cat feces or cysts in infected meat
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
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.
Dx?
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?
- sporozoites from mosquito enter the bloodstream, and migrate to the liver.
- infect liver cells, where they multiply into merozoites, rupture the liver cells, and return to the bloodstream.
- The merozoites infect RBCs, where they develop into ring forms= trophozoites and schizonts that in turn produce further merozoites.
- Sexual forms are also produced, which, if taken up by a mosquito, will infect the insect and continue the life cycle.
Aunt was hiking in upstate NY about a week ago. She currently has a fever and went to the doctor for fatigue. She has hemolytic anemia. During a peripheral smear they found something she described as a little 4 point shape (see below) and started her on Quinine + Clindamycin
Dx?
How did she get this?
Babesia Microti
(maltese cross= Merozoite in peripheral smear, can also look like a Trohpozoite ring but lacks pigments seen in malaria)
Vector = Ixodes tick and often co-infection with Lyme
Pt from Egypt comes with ulcer on his arm. He has had spiking fevers and you note hepatosplenomegaly and his labs show pancytopenia. You get a blood smear and see tons of red dots inside a macrophage.
Whats the Dx?
What’s it transimtted by?
Tx?
Leishmania Donavani
Visceral and Cutaneuos leishmaniasis and transmitted by SAND FLY
Spiking fever, hepatosplenomegaly, pancytopenia and cutaneous have ulcers slow to heal
Dx: Macrophages with Amastigotes
You have recently switched your diet up to include less red meat and repladed it with fish. A few weeks later you feel weak and tired. You have conjuctival pallor. The doctor shows you your blood smear and it is full of hyper segmented neutrophils.
Whats the Dx?
Whats the causitive agent?
What’s the tx?
B12 deficiency–> Megaloblastic anemia
Diphyllobothrium Latum: Fish tape worm; ingested in raw fish
Tx: Praziquantel
