This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Miscellaneous, Subject name: Medicine
In genital TB, the menstrual blood 
Select and explain. 
A. Does not contain tuberculids, B. Contain tuberculids on all days of menstruation, C. Tuberculids on the first day of menstruation only, D. Tuberculids on (last) day of menstruation only
A: Does not contain tuberculids
Answer: A: Does not contain tuberculids 
Explanation: (A) Does not contain tuberculids# Definitive diagnosis of TB requires isolation of tubercle bacilli via culture.> Bacteriological examination of menstrual blood with acid fast bacilli (AFB) smear and cultures is recommended by some but sensitivity is very low.> Menstrual fluid collected within 12 hour after onset of menses & cultured was found to be positive for tuberculosis in 10% of cases.