microbiology midterm drugs

Question 1

acanthamoeba species

Answer 1

pentamidine, ketoconazole, flucytosine

Question 2

naegleria fowleri

Answer 2

Amphotericin B, miconazole, rifampin

Question 3

candida albicans

Answer 3

thrush- nystatin swish and spit.
cutaneous infection topical imidazole
more severe infections related to immunocompromised- fluconazole and amphotericin B

Question 4

aspergiullus fumigatus, flavus and niger

Answer 4

diagnosis:
amicro, cultivation hemoculture.
treat: 
allergic type-corticosteroids.
aspergiolloma- removal via surgery.
inasive aspergillosis- amophotericin B or caspofungin

Question 5

plasmodium

Answer 5

diagnosis:

1) thin/thick blood film examination for signet shaped rings in RBC.
2) PCR
3) Immunochromatography.
4) serology IFA

treatment:
vivax+ovale= chlorquine+primaquine for hypnozoite.
Prophylaxis= doxycycline
extermination of mosquitoes with pesticides.
malariae= chloroquite.
falciparum= qunine/mefloquine/ artemesinin.
.

Question 6

Giardia lamblia

Answer 6

diagnosis:
1. stool specimen /w cyst+trophozoites.
one stool specimen per day for 3 ddays!
2. Duodenal aspiration
3. immunological tests for antigen presence.
Treat: metronidazole.

Question 7

trypanosoma

Answer 7

diagnosis:
1) visualize trypomastigotes in blood, spinal fluid or lymph node.
2) Serology (high Igm Titers, due to antigenic variation)
3) Weinmann media to detect epimastigote. (culture)
4) Antibody agglutination test for T gamiense or animal inoculation for rhoesiense.

treat:
Early stage- suramin.
late- tryparsamide
or both stages: eflornithine

Question 8

chagas disease

Answer 8

diagonosis:
blood film(c shaped T cruzi)
biopsy of node, liver spleen (amastigotes)
culture( epimastigote)
xenodiagnosis
serological test
cruzin test
molecular techniques.

treat: nifurtimox (inhibit intracellular growth)
or primaquine (destroys trypansoma in blood)

Question 9

toxplasma gondii

Answer 9

sample: muscle biopsy, lymph node aspirate, blood.
serology: IF, elisa (AA IGA)
Microscope:giemsa.

treatment:

• > spiramycin, sulphonamids
• > Pyrimethamine for newborns.
  prevention: cook meat, avoid cats.

Question 10

what do you use against trematodes and cestodes?

Answer 10

praziquantel, niclosamide.

Question 11

what do you use against nematodes?

Answer 11

albendazol, mebendazol,thiabendazol.

levamisol.

Question 12

taenie solium and saginata

Answer 12

diagnosis:
for solium+saginata=
fecal exam of proglottids+eggs.
for solium also:
CT scan or biopsy of brain with revaled calcified cysticerci.

treat: praziquantel.

Question 13

echinococcus

Answer 13

Pathogenesis: dogs release the eggs  intermediate hosts
uptake the eggslarvae hatch in the intestine invade the
mucosa layer and reach the organs by blood circualtion and
form hydatid cysts in the liver, lungs, brain
Dogs eat infected intermediate host animals larvae can
develop to adult helminth thus completing the lifecycle

Diagnosis: UH, CT, Serology, presence of hookletrs is diagnostic for hydatidosis.
Therapy: albendazole+ operation (prevent anaphylaxy)

Question 14

fasciola hepatica

Answer 14

Pathogenesis
Cercaria are consumed by food (watercress)- in the intestine they invade in the
mucosalayer reach the liver adult helminths develop  after
fertilization the eggs are layed in the bile and released by stool

Clinical features
hepatomegalia, hepatitis, eosinophilia, choledochus obstruction,
Diagnosis: egg detection from the stool
 egg detection from the bile
Therapy: benzimidazol

Question 15

Schistosoma – S. mansoni,

S. japonicum, S. haematobium

Answer 15

S. mansoni, S. japonicum – intestinal Schistosomiasis
cercariae penetrate through the skin  by blood circualtion they reach the v. mesenterica
adult helminthes develop  eggs are layed in the vessels by the irritation they enter the
intestine and released by stool

S. haematobium: bladder Schistosomiasis
cercariae penetrate through the skin  by blood circualtion reach the urinary vena
adult helminthes develop  eggs are layed in the vessels by the irritation they enter the
bladder (or ureters) eggs are released by urine

Diagnosis: S. mansoni, S. japonicum – egg detection from stool
S. haematobium – egg detection from urine

treatment: Praziquantel

disease:

1. dermatitis at penetration area.
2. katayama fever with laying of eggs- fever, hives, headache weight loss and cough (can last up to 3 weeks, after 4-8 weeks).
3. chronic fibrosis at areas of fibrosis.

Question 16

Ancylostoma duodenale,

Necator americanus

Answer 16

Filariform larvae penetrate the skin
with the circulation they reach the lungs,
coughed up and swallowed back  in the
intestine adult helminths develop after
fertilization eggs are layed and released
with the stool 
In the soil rhabditiform larvae hatch and
develop to filariform larvae

clinic:
pneumonia.
nausea, diahrrhea vomit.
hepatosplenomegaly blood loss etc.

diagnosis: stoll exam for eggs.
treatment: mebendazole.

Question 17

Enterobius vermicularis

pinworm

Answer 17

Infection by consuming embryonated eggs stomach
acid and digestive enzymes lyse the egg wall
Larvae hatch in the small intestine
female and male adult helminths develop  after
fertilization female worms lay the eggs in the perianal
fold (20.000 eggs/day) at night usually.

autoinfection and direct person-to-person transmission

perianal itch is the main symtpom.

diagnosis: scotch tape near perianal region and see eggs under microscope.
worms can be seen macroscopically at night.

therapy: albendazole.

Question 18

Ascaris lumbricoides

Answer 18

Infection by consuming infective eggs
stomach acid and digestive enzymes lyse
the egg wall
Larvae hatch in the intestine
 invade the intestinal mucosa and carried
by blood circulation  reach lungs ,
trachea, throat  swallowed back to
intestine in the small intestine, they
develop into adult worms after
fertilization the female worms lay eggs in
the intestine and released by stool eggs
stay in the soil to get embryonated.

The symptoms appear by the migration
 peritonitis, eosinophil pneumonitis, dyspnoe,
coughing up larvae, intestinal obstrucitons
Diagnosis:
Larvae in the sputum
Eggs in the stool  seen by microscope
Helminths in the stool  seen by naked eyes
Therapy: albendazole