Question

Schuffner’s dots are related to
A. RBC of man
B. Leucocytes of frog
C. Epithelium of stomach of mosquito
D. Entamoeba histolytica

Answer 1

Schuffner’s dots (also known as Schuffner’s granules) are the morphological changes that take place in erythrocytes of man infected with the malarial parasite. Schuffner’s dots help in detection of malaria.

Complete answer:
• Malaria is a disease that is caused due to transmission of malarial parasites by the bite of infected mosquitoes.
• Four parasites can cause malaria in humans. These include – Plasmodium vivax, Plasmodium ovale, Plasmodium malariae and Plasmodium falciparum.
• Malaria is detected by observing the microscope slide containing blood smear of the infected person under a microscope. Before examination, the blood is stained with stains such as Giemsa stain and Romanowsky stain to identify the parasite and parasite induced changes in blood. Malarial parasites cause changes in the erythrocytes or RBC’s of man. RBC’s infected with Plasmodium vivax and Plasmodium ovale shows enlargement and presence of brick red colored dots. These dots are nothing but Schuffner’s dots. Plasmodium malariae do not cause any morphological changes in RBCs, hence RBCs infected with them do not show Schuffner’s dots. Schuffner’s dots are also absent in RBCs infected with Plasmodium falciparum.
• Leucocytes of frogs are types of blood cells that do not get infected with malarial parasites. Hence, they do not show schuffner’s dots.
• Epithelium of the stomach of the mosquito does not show Schuffner's dots.
• Schuffner’s dots are also not shown by Entamoeba histolytica. Entamoeba histolytica is an intestinal parasite that is found in the large intestine of man.

Hence, the correct answer is option (A).

Note: All the four malarial parasites infect the erythrocytes or red blood cells. They show different erythrocytic life stages like ring form, trophozoite, schizont and gametocytes. The trophozoite, schizont and gametocytes stages of Plasmodium ovale and Plasmodium vivax bring about various morphological changes in erythrocytes that appear as schuffner’s dots during blood smear examination under light microscope.