RT Book, Section A1 Purandare, Amol A2 Kline, Mark W. SR Print(0) ID 1182936841 T1 Syphilis T2 Rudolph's Pediatrics, 23e YR 2018 FD 2018 PB McGraw-Hill Education PP New York, NY SN 9781259588594 LK accesspediatrics.mhmedical.com/content.aspx?aid=1182936841 RD 2024/04/24 AB Syphilis is a sexually transmitted infection caused by Treponema pallidum. The organism is a motile, thin spirochete 6 to 20 μm long that has the appearance of a helical coil on dark-field microscopy or immunofluorescence. It is a fastidious organism, with a short life span out of host, and is unable to grow on culture media.