Answer to Case 718

 Answer to theParasite Case of the Week 718: ciliated epithelial cells; NOTLophomonas. Many of our readers suspected this case to representLophomonas blattarum- a flagellated protozoan parasite of cockroaches - but there is no convincing evidence thatLophomonas is actually a human parasite. Also, there are a number of helpful features that can differentiate ciliated human epithelial cells fromL. blattarum:1. Human ciliate epithelial cells have a well-defined terminal bar with a compact row of short cilia (arrows) rather than the tuft of long flagella possessed byLophomonas.  This is nicely demonstrated by this additional photograph from the same case:2. The nucleus is located in a basilar position (rather than apical, as withLophomonas). 3. The beating motility of ciliated epithelial cells is very rhythmic and non-direction compared with trueLophomonas.For those of you who are asking " what about the PCR evidence implicatingLophomonas blattarumas a human pathogen in respiratory samples?? " Well, a thorough analysis of the PCR primers conducted by my colleague, Dr. Richard Bradbury revealed these primers to show a lot of cross-reactivity, particularly with the oral trichomonads. Therefore, amplification using this PCR in respiratory specimens would not be conclusively supportive ofLophomonas.Again, though, the difference in motility patterns between ciliated human epithelial cells andLophomonasare really striking, and allows for definitive differe...
Source: Creepy Dreadful Wonderful Parasites - Category: Parasitology Source Type: blogs