Parasites Flashcards
To be able to summarise the life cycles, clinical features & management of the following parasitic infections:
Plasmodia (malaria)
Leishmania
Giardia
Taenia
Plasmodia (malaria):
Life cycle: Malaria is caused by Plasmodium parasites that are transmitted to humans through the bite of infected Anopheles mosquitoes. The parasites then infect and multiply inside the red blood cells, leading to their destruction and the release of toxins that cause the symptoms of malaria.
Clinical features: Malaria typically presents with flu-like symptoms such as fever, chills, headache, and body aches. In severe cases, it can lead to organ failure, coma, and death.
Management: Malaria is treated with antimalarial drugs such as chloroquine, artemisinin-based combination therapies (ACTs), and quinine. Prevention measures include the use of insecticide-treated bed nets, insect repellents, and prophylactic antimalarial drugs for travelers to endemic areas.
Leishmania:
Life cycle: Leishmania is a parasitic protozoan that is transmitted to humans through the bite of infected sandflies. The parasites then infect immune cells and can cause a variety of clinical manifestations.
Clinical features: Leishmaniasis can present as a cutaneous, mucocutaneous, or visceral disease, depending on the species of Leishmania and the immune status of the patient. Cutaneous leishmaniasis typically presents as a skin ulcer, while mucocutaneous leishmaniasis affects the mucous membranes of the nose, mouth, and throat. Visceral leishmaniasis (also known as kala-azar) affects the internal organs and can cause fever, weight loss, and an enlarged spleen and liver.
Management: Treatment of leishmaniasis depends on the species and severity of the infection. Antimonial drugs, such as sodium stibogluconate and meglumine antimoniate, are the mainstay of treatment. Liposomal amphotericin B is also effective for visceral leishmaniasis. Prevention measures include the use of insecticide-treated bed nets and insect repellents.
Giardia:
Life cycle: Giardia is a parasitic protozoan that is transmitted to humans through the ingestion of contaminated water or food. The parasites then infect the small intestine and can cause diarrhea.
Clinical features: Giardiasis typically presents with diarrhea, abdominal cramps, and bloating. In severe cases, it can lead to malabsorption and weight loss.
Management: Giardiasis is treated with antimicrobial drugs such as metronidazole and tinidazole. Prevention measures include ensuring the safety of drinking water sources and practicing good hygiene.
Taenia:
Life cycle: Taenia is a parasitic tapeworm that can infect humans through the ingestion of contaminated meat. The adult tapeworms live in the intestines of the definitive host (usually a carnivorous animal), while the eggs are excreted in the feces and can contaminate the environment. Humans become infected by consuming undercooked or raw meat containing the cysticerci (larval stage) of the tapeworm.
Clinical features: Taeniasis (infection with the adult tapeworm) is usually asymptomatic, but can cause mild gastrointestinal symptoms such as nausea, diarrhea, and abdominal pain. Infection with the larval stage (cysticercosis) can cause a variety of clinical manifestations depending on the location of the cysts, including seizures, blindness, and spinal cord compression.
Management: Taeniasis is treated with anthelminthic drugs such as praziquantel and niclosamide. Cysticercosis is treated with the same drugs
