Parasitology-2 Flashcards
Which malaria species can cause splenomegaly?
P. vivax, P. ovale, P. malariae (due to chronic immune activation).
What is “malarial retinopathy”?
Retinal hemorrhages and whitening seen in severe falciparum malaria.
What is “Recrudescence” in malaria?
Relapse of malaria due to incomplete clearance of RBC forms (without liver hypnozoites). Seen in P. falciparum and P. malariae.
Which type of reproduction occurs in mosquitoes for Plasmodium?
Sexual reproduction (sporogony).
What is the role of PfEMP1 in malaria?
PfEMP1 (Plasmodium falciparum erythrocyte membrane protein 1) mediates cytoadherence and antigenic variation, leading to immune evasion.
Why does P. vivax have lower parasitemia than P. falciparum?
Because P. vivax infects only young RBCs (reticulocytes).
What is the significance of Maurer’s clefts?
They are irregular cytoplasmic inclusions seen in P. falciparum-infected RBCs.
What is the role of Hemozoin in malaria?
Hemozoin is a byproduct of hemoglobin digestion by Plasmodium and is responsible for dark pigment in malaria-infected tissues.
Durck Granuloma is seen in
P. falciparum
Algid malaria
Malaria with circulatory failure
Screening method of choice for malaria
Kawamoto technique- acridine orange.
Thick smear vs thin smear for malaria diagnosis
Thick- to quantify
Thin- for identification
Gold standard for diagnosis of malaria
Light microscopy
____ OIF is examined before reporting malaria negative
200-300
Thick smear vs thin smear sensitivity
Thick- 5 parasites/ microlitre
Thin- 200 parasites/ microlitre
Stains used for microscopy of malaria
Romanowsky stain
JSB stain
Ziemann’s dots seen in
P. malariae
James dots a/w
P. ovale
RDT for malaria
1. Principle
2. Sensitivity
3. Membrane used
- Immunichromatography
- 50-100/ microlitre
- Nitrocellulose membrane
Maltese cross appearance of RBC seen in
Babesia
Babesia
1. Definitive host
2. Intermediate host
3. Accidental dead end host
- Hard tick
- Rodent/ mammal
- Humans
Types of Babesia and CF
B. microti (host- rodent)
B. divergens (host- cattle)
CF- fever, chills, sweating
Tx of Babesia
Azithromycin + Atovaquone
Severe: Clindamycin + Quinine
Autofluorescence shown by which diarrhoea causing parasite
Cyclospora
Isospora
Tx of
1. Cyclospora, Isospora
2. Cryptosporidium
- Cotrimoxazole
- Nitazoxanide
What are the three main parts of a cestode?
Scolex (head), neck, and proglottids (body segments).
Differences between heads of cestodes
Taenia solium (Pork Tapeworm)- 4 suckers, 2 rows of hooks
Taenia saginata (Beef Tapeworm)- 4 suckers
Diphyllobothrium latum (Fish Tapeworm)- 2 suctorial grooves/ bothria
Echinococcus granulosus (Dog Tapeworm)- 4 suckers, 2 rows of hooks
Hymenolepis nana (Dwarf Tapeworm)- 4 suckers, single row of 20-30 hooks
H.diminuta- 4 suckers
All of the ones with ‘ta’ doesnt have hooks
What is the definitive host for Schistosoma?
Man
What is the first intermediate host for Paragonimus westermani?
Snail
What is the second intermediate host for Clonorchis sinensis?
Clonor fish
What is the infective form of Schistosoma?
Cercaria larva
How does Schistosoma transmit to humans?
Through skin penetration
What type of eggs do adult Schistosoma produce?
Spinous egg
What is the treatment for Schistosoma infection?
Praziquantel
What clinical condition does S. Haematobium cause?
Haematuria
Where does S. Mansoni primarily affect?
Inferior Mesenteric plexus
What is a clinical manifestation of Fasciola hepatica?
Jaundice
What is the infective stage of Ascaris Lumbricoides?
Embryonated egg
What is the treatment for Ascaris Lumbricoides infection?
Albendazole
What is the mode of transmission for Trichuris trichiura?
Ingestion
What clinical condition is associated with Trichuris trichiura?
Dysentery
What is the infective stage of Enterobius vermicularis?
Embryonated egg
What is a diagnostic method for Enterobius vermicularis?
Scotch tape method
What is the common name of Hymenolepis nana?
Dwarf tapeworm
What is the mode of transmission of Hymenolepis nana?
Fecal-oral route (ingestion of eggs)
Autoinfection (eggs hatch in the intestine)
Ingestion of infected arthropods (like beetles)
What are the characteristic features of Hymenolepis nana scolex?
Small, rounded scolex
Four suckers
Retractable rostellum with a single row of hooks
What is the life cycle of Hymenolepis nana?
Eggs ingested → hatch into oncospheres
Penetrate intestinal wall → form cysticercoid larvae
Mature into adult worms in the intestine
Eggs released in feces or undergo autoinfection
What are the clinical features of Hymenolepis nana infection?
Mostly asymptomatic
Abdominal pain, diarrhea, nausea
Weight loss
Eosinophilia (mild)
What is the diagnostic method for Hymenolepis nana?
Stool examination for eggs
Eggs are oval, thin-shelled, with polar filaments
What is the treatment of choice for Hymenolepis nana?
Praziquantel (DOC)
Alternative: Niclosamide
How does Hymenolepis nana differ from Hymenolepis diminuta?
H. diminuta is larger, has no hooks, transmits only via insects and shows no autoinfection
How to differentiate between H. nana and H. diminuta life cycles?
Only between humans- H. nana
Btween humans and rats- H. diminuta
