This is a real-world medical entrance exam question, please give the true answer based on the question and selection. Topic name: Preterm Labour, Subject name: Gynaecology & Obstetrics
Premature baby at 34wk was delivered & had bullous lesion on body. X ray shows periostitis next investigation is 
Select and explain. 
A. ELISA for HIV, B. PCR for TB, C. VDRL for mother & baby, D. HbsAg for mother
C: VDRL for mother & baby
Answer: C: VDRL for mother & baby 
Explanation: The above mentioned history is suggestive of Congenital Syphilis.So we will do VDRL of both mother and baby to confirm. Early Congenital syphilis Late Congenital syphilis appearing 2-6 weeks after bih untreated after 2 years of age Rhinitis, or "snuffles" Mucocutaneous lesions Bone changes :Osteochondritis, osteitis, and periostitis detectable by x-ray Long bones Hepatosplenomegaly, lymphadenopathy , Anemia, jaundice , Thrombocytopenia; and leukocytosis. Interstitial keratitis (occurs at 5-25 years of age), Eighth-nerve deafness, Recurrent ahropathy. B/L knee effusions - Clutton's joints. Gummatous periostitis occurs at 5-20 years of age. Classic stigmata -Hutchinson's teeth, "Mulberry" molars , Saddle nose and Saber shins.