GI: Protozoa

Question 1

• Non-bloody diarrhea
• Foul-smelling (maloderous) Steatorea
• Fatty diarrhea
• Bloating
• Flatulence
• Weight-loss
• “Went Camping” and “Drank stream water”
• Pool sanitation / Day care centers - Cysts in water
• String test

Answer 1

Giardia lamblia (Giardiasis)

• Tx: Metronidazole

Question 2

• Bloody diarrhea
• Dysentery
• Liver abscesses (“anchovy paste” exudate)
• RUQ pain
• ‘Rain drop’ or ‘Flasked-shaped ulcer if submucosal abscess of colon ruptures
• Cysts in water - Fecal oral
• Keratitis
• Homosexual males

Answer 2

Entamoeba histolytica (Amebiasis)

• Tx: Metronidazole, Iodoquinol for asymptomatic cyst passers

Question 3

• Watery diarrhea
• Persistant and Severe diarrhea in AIDS pts.
• Not killed by Chlorine
• Undercooked meat
• Contaminated water
• Acid Fast oocyte in Stool
• -> especially when CD4+ < 200 cells/mm³

Answer 3

Cryptosporidium

• Tx: Supportive, and Water Purification prevention

Question 4

• Mononuclease-like
• Cat feces: crosses placenta –> Birth defects, Retardation, Choriocentisis
• Encephalitis (HIV) - brain abcess in HIV (seen as ring-enhancing brain lesions on CT / MRI
• Congenital toxoplasmosis - “Classic triad”
  
  • Chorioretinitis (inflammation of the choroid)
  • Hydrocephalus
  • Intracranial calcification
• Cysts in meat or oocysts in cat feces

Answer 4

Toxoplasma gondii

• Tx: Sulfonamide + Pyrimethamine

Question 5

• Rapidly Fatal Meningoencephalitis
• Swimming in Freshwater lakes (Nalgene bottles)
• Enters via Cribiform plate
• Amoebas in Spinal fluid

Answer 5

Naegleria fowleri

• Tx: Amphotericin B has been effective for a few survivors

Question 6

• African Sleeping sickness
• Recurring Fever (due to antigenic variation)
• Enlarged lymph nodes
• Somnolence, Coma
• Tsetse fly –> a painful bite

Answer 6

Trypanosoma brucei rhodesiense

Trypanosoma brucei gambiense

• Tx:
  
  • Blood –> Suramin
  • CNS –> Melarsoprol

Question 7

• Cyclical Fever
• Headache
• Anemia
• Splenomegaly
• Banana shaped

Answer 7

Plasmodium (Malaria)

P. vivax / ovale –> 48 hrs

P. falciparum –> Irregular

P. malariae –>72 hrs

• Chloroquine
• If resistant –> Mefloquine or Atovaquone / Proguanil
• If Life threatening –> Quinidine and test for G6PD deficiency
• Vivax / Ovale - add Primaquine for Hypnozoite

Question 8

• Fever and Hemolytic anemia
• Predominantly in Northeastern United States
• Asplenia and increased risk of Severe disease
• Ixodes tick
• Blood smear to confirm, ring form
• “Maltese cross”

Answer 8

Babesia

• Tx: Atovaquone + Azithromycin

Question 9

• Dilated Cardiomyopathy, Myocardidis
• Periorbital swelling
• Reduviid bug “kissing bug”
• Megacolon
• Megaesophagus
• Predominantely in South America and Florida

Answer 9

Trypanosoma cruzui (Chagas)

• Tx: Benzindazole or Nifurtimox

Question 10

• Spiking fevers
• Hepatosplenomegaly
• Anemia
• Thrombocytopenia
• Pancytopenia
• Black skin lessions ‘Black illness’
• Sandfly bite
• Macrophages containing amastigotes

Answer 10

Leshmania donovani (Kala-azar disease)

• Tx: Amphtericin B
• Stibogluconate sodium

Question 11

• Vaginitis / Urethritis
• ‘Fish-like’ - Malodorous
• Itching and Burning
• Yellow-green / watery discharge
• ‘Strawberry vagina’ / ‘cervix’
• STDs / Fomites
• Abnormal Alkalinity of Vagina is favorable
• Trophozoites on wet mount

Answer 11

Trhichomonas vaginalis

• Tx: Metronidazole for Pt. and Partner.