The reaction shown in the picture below is due to?
A. Capsular swelling.
B. Mitochondrial swelling.
C. RBC swelling.
D. Ribosomal swelling.
Ans:A. Capsular swelling.
Quellung reaction is due to capsular swelling.
- Also called the Neufeld reaction.
- It is a biochemical reaction in which antibodies bind to the bacterial capsule of Streptococcus pneumoniae, Klebsiella pneumoniae, Neisseria meningitidis, Haemophilus influenzae,Escherichia coli, and Salmonella.
- The antibody reaction allows these species to be visualized under a microscope.
- If the reaction is positive, the capsule becomes opaque and appears to enlarge.
- Quellung is the German word for “swelling” and describes the microscopic appearance of pneumococcal or other bacterial capsules after their polysaccharide antigen has combined with a specific antibody.