Lecture 19: Fungal & Protozoan Diseases

Question 1

Mycoses

Answer 1

Fungal diseases

Question 2

Pathogenic fungi characteristics

Answer 2

• mycoses
• 300 fungal species produce disease in humans
• airborne transmission
• route of infection: direct contact or systemic infections-> have disseminated to visceral tissues

Question 3

Pathogenic protists characteristics

Answer 3

• protozoa: adapted to every type of habitat on earth
• transmission via: arthropod vectors, contaminated food and water, direct contact

Question 4

Piedras

Answer 4

• superficial/ cutaneous fungal infection
• infections of hair shaft

Question 5

Tineas

Answer 5

• superficial/ cutaneous fungal infections
• infection outer layer of skin, nails and hair
• Ex. ringworm, tinea cersicolor

Question 6

Coccidiomycosis

Answer 6

• systemic fungal infection
• caused by coccidioides immitis
• AKA valley fever
• fungus grows as a mold
• diagnosis by identification of spherules in pus
• treated with fluconazole, itraconazole and amphotericin B

Question 7

Histoplasmosis

Answer 7

• systemic fungal infection
• lung disease caused by Histoplasma capsulatum
• inhalation of microconidia from bird and bat droppings
• grows in macrophages
• can appear in the lungs
• prevented by wearing protective clothing and masks infested habitats
• treated with amphotericin B

Question 8

Protozoan diseases attributes

Answer 8

• vector: mosquitos, flies, ticks
• difficult to treat due to eukaryotic cell structure (like fungi)
• have complex life cycles involving a few hosts

Question 9

Malaria

Answer 9

• protozoan disease
• caused by 5 species of plasmodium
• transmitted by bite of an infected female mosquito

Question 10

Malaria clinical Info

Answer 10

• symptoms: shaking chills, fever and sweating
• anemia can result and the spleen and liver become enlarged
• treatment: chloroquine

Question 11

Leishmaniasis

Answer 11

• protozoan disease
• caused by leishmania
• transmitted by sandflies
• protozoa within infected macrophage and serological tests
• treated with paromomycin, liposomal amphotericin B

Question 12

African sleeping sickness

Answer 12

• protozoan disease
• caused by tryanosoma brucei
• transmitted by tsetse flies
• pass through lymphatic system, enter bloodstream, and replicate by binary fission
• symptoms: fever, headache, extreme fatigue, muscle and joint aches
• treatment based on stage of infection

Question 13

Chagas disease

Answer 13

• protozoan disease
• Causedby trypanosoma cruzi
• Transmitted by kissing bug as
• after blood meal, trypanosomes are discharged in the insect’s feces, which contains irritant that stimulates scratching, allowing parasite to enter blood
• No vaccine due to antigenic variation

Question 14

Trichomoniasis

Answer 14

• protozoan STD
• trichomonas vaginalis: protist spread by direct contact during sex
• males may be asymptomatic, females develop yellow vaginal discharge and itching
• Treatment: metronidazole

Question 15

Food and waterborne protists

Answer 15

• Entamoeba histolytica: amoebic dysentery
• giardia lamblia: giardiasis
• naegleria fowleri: brain eating amoeba

Question 16

Toxoplasmosis

Answer 16

• parasite of cats
• caused by Toxoplasma gondii
• cat is required for completion of sexual cycle
• transmission to humans: ingestion of oocytes while cleaning litter box, consumption of infected meat an maternal fetal transmission

Question 17

Toxoplasmosis symptoms

Answer 17

• lymph node swelling
• pulmonary necrosis, myocarditis, and hepatitis caused by tissue necrosis
• Treatment: pyrimethamine and sulfadiazine
• avoid eating raw meat, washing hands after soil owek and keeping cat household clean

Question 18

Aspergillosis

Answer 18

• opportunistic infection
• caused by fungus Aspergillus fumigatus
• invasive disease results in pulmonary infection
• with fever, chest pain and cough that disseminates to brain, kidney, liver, bone, or skin

Question 19

Candidiasis

Answer 19

• opportunistic infection
• caused by members of genus Candida
• Known as “yeast infections”
• most infections involve the skin or mucous membrane
• disease can occur in the absence of competing microbiota

Question 20

Cryptococcus

Answer 20

• opportunistic infection
• caused by cryptococcus gattii
• manifests as pneumonia and/ or meningitis with a mortality rate of about 33%
• Observed in HIV, cancer, and organ transplant patients
• Treatable with amphotericin b

Question 21

Pneumocystis pneumonia

Answer 21

• opportunistic pneumonia
• Pneumocystis jiroveci: fungus found in the lungs of a wide variety of mammals
• Occurs almost exclusively in immunocompromised hosts