Fungi Flashcards
Histoplasmosis
Mississippi and Ohio river valley - Bird or Bat Droppings
Pneumonia
Macrophage filled with Histoplasma (Histo Hides)
Blastomycosis
East of Mississippi River and Central America
Inflammatory Lung Dz (pneum) and can disseminate to skin and bone (Granulomatous nodules)
Broad-base budding (Blasto Buds Broadly)
Coccidioidomycosis
Southwestern US, Cali, San Joaquin Valley (Valley Fever) - spores in dust become spherules in lungs - incr rate after earthquakes
Pneumonia and Meningitis
Spherule filled with endospores (larger than RBC)
Paracoccidioidomycosis
Latin America
Pneumonia
Budding yeast with Captain’s Wheel formation (larger than RBCs)
Malassezia furfur
Tinea versicolor (cutaneous mycoses) in Hot Humid weather
Degredation of lipids produces acids that damage melanocytes and cause hypo or hyperpigmentation.
Spaghetti and meatball appearance on KOH prep
tx - topical miconazole, selenium sulfide
Candida albicans
Dimorphic yeast
Systemic or Superficial
Oral and Esophageal thrush in immunocompromised, vulvovaginitis in diabetics, diaper rash, endocarditis in IV drug users, chronic mucocutaneous candidiasis
Tx - topical azole, fluconazole, caspofungin, ampotericin B
Aspergillus fumigatus
- Allergic bronchopulmonary aspergillosis with asthma or CF
- Aspergillomas in lung cavities after TB infxn
- Aflatoxins - Hepatocellular Carcinoma
- Invasive or disseminated dz in immunocompromised (lung)
Acute Angles in Aspergillus
Cryptococcus neoformans
Encapsulated Yeast found in soil, pigeon droppings. Culture on Sabouraud’s agar. India Ink Stain. Latex agglutination test detects polysaccharide capsular antigen
Acquired thru inhalation with hematogenous dissemination
Cryptococcal meningitis, cryptococcosis
Soap Bubble lesions in the brain
Mucor and Rhizopus spp.
Mucormycosis - irregular broad nonseptate hyphae branching at wide angles
Dz mostly in ketoacidotic diabetic and leukemic patients
Fungi prolif in blood vessel walls with excess ketone and glucose, penetrate cribiform plate, and enter brain -> Rhinocerebral, frontal lobe abscess -> Headache, facial pain, black nexcrotic eschar on face (CN involvement sometimes)
Pneumocystis jiroveci
Disk-shaped Yeast on methenamine silver stain
Diffuse interstitial pneumonia (most asymp unless immunosuppressed - HIV patients)
Diffuse bilateral CXR appearance, Dx by lung biopsy or lavage
Tx - TMP-SMX, pentamidine, dapsone
Sporothrix schenckii
Dimorphic, cigar-shaped budding yeast that lives on vegetation.
Rose Gardener’s Dz - traumatically introduced to skin by thorn causing local pustule or ulcer with nodules along draining lymphatics (ascending lymphangitis)
Tx - itraconazole or POTassium iodide (Plant a rose in the POT)
Giardia lamblia (GI)
Cysts in water
Giardiasis - bloating, flatulence, foul-smelling, fatty diarrhea (campers/hikers)
Dx - Trophozoites or cysts in stool
Tx - Metronidazole
Entamoeba histolytica (GI)
Cysts in water
Amebiasis - bloody diarrhea, liver abscess (reddish brown), RUQ pain (flask-shaped ulcer if submucosal abscess of colon ruptures)
Dx - serology, trophozoites (w/ RBCs in cytoplasm), or cysts (w/ mult nuclei) in stool
Tx - Metronidazole and Iodoquinol
Cryptosporidium (GI)
Cysts in water Severe diarrhea in AIDS Watery diarrhea in normal Dx - Cysts on acid-fast stain Px - filter water Tx - Nitazoxanide
Toxopasma gondii (CNS)
Cysts in meat or cat feces - crosses placenta
Brain Abscess in HIV (ring enhancing brain lesion)
Congenital toxoplasmosis - 1.Chorioretinitis 2. Hydrocephalus 3. Intracranial calcifications
Dx - Serology, biopsy
Tx - Sulfadiazine + Pyrimethamine
Naegleria fowleri (CNS)
Swimming in freshwater lakes (Nalgene bottle filled with freshwater Naegleria) - enter thru cribiform plate
Rapidly Fatal Meningoencephalitis
Dx - Amoebas in spinal fluid
Tx - Amphotericin
Trypanosoma brucie, gambiense, rhodesiense (CNS)
Tsetse fly - painful bite
African Sleeping sickness - large lymph nodes, recurring fever (antigenic variation), somnolence, coma
Dx - Blood smear
Tx - Suramin (bood-borne dz), Melarsoprol (CNS penetration)
Plasmodium vivax/ovale, falciparum, malariae (hematologic)
Mosquito (Anopheles)
P. vivax/ovale - 48hr cycle (tertian - fevers 48hrs apart), dormant form in liver
P. falciparum - sever, irregular fever patterns, parasitized RBCs occlude capillaries in brain (cerebral malaria), kidneys, lungs
P. malariae - 72hr cycle (quartan)
Dx - blood smear, trophoziote ring form, RBC schizont with merozoites
Tx - Chloroquine, Mefloquine, (if vivax/ovale add primaquine for dormant form)
Babesia (hematologic)
Ixodes tick (same as Borrelia burgdorferi)
Babesiosis - fever, hemolytic anemis - predominantly in northeastern US (aspleina incr risk of sever dz)
Dx - Blood smear, ring form, “Maltese Cross”
Tx - Quinine, Clindamycin
Trypanosoma cruzi (visceral)
Reduviid bug (kissing bug) - painless bite (like a kiss)
Chaga’s dz - dilated cardiomyopathy, megacolon, megaesophagus (South America)
Dx - Blood smear
Tx - Nifurtimox
Leishmania donovani
Sandfly
Visceral leishmaniasis (kala-azar) - spiking fevers, hepatosplenomegaly, pancytopenia
Dx - Macrophages containing amastigotes
Tx - Sodium stibogluconate
Trichomonas vaginalis
Sexual
Vaginitis - foul-smelling greenish discharge, itching, burning (do not confuse with Gardnerella vaginalis - gram- bact)
Dx - Trophozoites (motile) on wet mount
Tx - Metronidazole for pt and partner
