Fungi

Question 1

Histoplasmosis

Answer 1

Mississippi and Ohio river valley - Bird or Bat Droppings
Pneumonia
Macrophage filled with Histoplasma (Histo Hides)

Question 2

Blastomycosis

Answer 2

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)

Question 3

Coccidioidomycosis

Answer 3

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)

Question 4

Paracoccidioidomycosis

Answer 4

Latin America
Pneumonia
Budding yeast with Captain’s Wheel formation (larger than RBCs)

Question 5

Malassezia furfur

Answer 5

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

Question 6

Candida albicans

Answer 6

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

Question 7

Aspergillus fumigatus

Answer 7

1. Allergic bronchopulmonary aspergillosis with asthma or CF
2. Aspergillomas in lung cavities after TB infxn
3. Aflatoxins - Hepatocellular Carcinoma
4. Invasive or disseminated dz in immunocompromised (lung)
   Acute Angles in Aspergillus

Question 8

Cryptococcus neoformans

Answer 8

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

Question 9

Mucor and Rhizopus spp.

Answer 9

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)

Question 10

Pneumocystis jiroveci

Answer 10

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

Question 11

Sporothrix schenckii

Answer 11

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)

Question 12

Giardia lamblia (GI)

Answer 12

Cysts in water
Giardiasis - bloating, flatulence, foul-smelling, fatty diarrhea (campers/hikers)
Dx - Trophozoites or cysts in stool
Tx - Metronidazole

Question 13

Entamoeba histolytica (GI)

Answer 13

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

Question 14

Cryptosporidium (GI)

Answer 14

Cysts in water
Severe diarrhea in AIDS
Watery diarrhea in normal
Dx - Cysts on acid-fast stain
Px - filter water
Tx - Nitazoxanide

Question 15

Toxopasma gondii (CNS)

Answer 15

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

Question 16

Naegleria fowleri (CNS)

Answer 16

Swimming in freshwater lakes (Nalgene bottle filled with freshwater Naegleria) - enter thru cribiform plate
Rapidly Fatal Meningoencephalitis
Dx - Amoebas in spinal fluid
Tx - Amphotericin

Question 17

Trypanosoma brucie, gambiense, rhodesiense (CNS)

Answer 17

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)

Question 18

Plasmodium vivax/ovale, falciparum, malariae (hematologic)

Answer 18

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)

Question 19

Babesia (hematologic)

Answer 19

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

Question 20

Trypanosoma cruzi (visceral)

Answer 20

Reduviid bug (kissing bug) - painless bite (like a kiss)
Chaga’s dz - dilated cardiomyopathy, megacolon, megaesophagus (South America)
Dx - Blood smear
Tx - Nifurtimox

Question 21

Leishmania donovani

Answer 21

Sandfly
Visceral leishmaniasis (kala-azar) - spiking fevers, hepatosplenomegaly, pancytopenia
Dx - Macrophages containing amastigotes
Tx - Sodium stibogluconate

Question 22

Trichomonas vaginalis

Answer 22

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