How many doses of IM penicillin would you recommend for a patient with biopsy confirmed syphilis proctitis?

Syphilis is not a common cause of proctitis but apparently the biopsy confirms it. Almost certainly, the patient has primary or secondary syphilis, and standard treatment for early syphilis, a single 2.4 MU dose of benzathine penicillin G, is sufficient. If other evidence is more consistent with syphilis >1 year in duration, such as the last plausible source contact, then, of course, the usual 3-dose regimen of BPG is indicated.

Best regards-- HHH, MD