Which of the following parasite causes anaemia?
**Core Concept:** Anaemia is a condition characterized by a decrease in the number of red blood cells or a decrease in their hemoglobin content, leading to a reduced ability of blood to carry oxygen. It can be caused by various factors, including parasitic infections.
**Why the Correct Answer is Right:** Schistosomiasis, caused by the parasitic flatworms Schistosoma, is one of the parasites that can lead to anaemia. The parasites invade the blood vessels, leading to inflammation, scarring, and damage to the liver, spleen, and intestines. This damage impairs the production of red blood cells and increases blood loss, resulting in anaemia.
**Why Each Wrong Option is Incorrect:**
A. Plasmodium falciparum (malaria): Malaria is a mosquito-borne disease caused by Plasmodium species. It affects the red blood cells, but the correct answer is Schistosoma due to its specificity for causing anaemia.
B. Trypanosoma cruzi (Chagas disease): Chagas disease is caused by Trypanosoma cruzi and primarily affects the cardiovascular system, leading to heart disease, rather than causing direct anaemia.
C. Giardia lamblia (Giardiasis): Giardiasis is a parasitic infection caused by Giardia lamblia, primarily affecting the gastrointestinal tract and causing diarrhea, abdominal pain, and malabsorption, rather than directly causing anaemia.
D. Leishmaniasis (leishmaniasis): Leishmaniasis is a group of diseases caused by Leishmania parasites, primarily affecting the immune system and causing fever, splenomegaly, and hepatosplenomegaly, rather than directly causing anaemia.
**Clinical Pearl:** Anaemia due to Schistosomiasis is known as "Coelomic oedema" or "Schistosomiasis-induced haemolysis." This type of anaemia is characterized by a decrease in red blood cells, haemoglobin, and haematocrit levels.
**Correct Answer:** Schistosoma (Schistosomiasis) - Schistosomiasis is caused by Schistosoma species, which primarily affect the gastrointestinal tract and spleen, leading to inflammation, fibrosis, and destruction of red blood cells, resulting in anaemia.