Parasitology for students and the rest of us
This patient is infested with Pediculus humanus capitis otherwise known as head lice. Pediculus humanus capitis are insects belonging to the family Pediculidae. The family also includes Pediculus humanus humanus (body louse) and Pthirus pubis (crab louse).
The patient is a 55-year-old male that comes to a Veterans Hospital on an outpatient basis for his periodic examination. He has a history of homelessness and chronic substance abuse. He states that he has clean not been abusing any substance for the past year. He also has a medical history significant for COPD, diabetes, and tobacco use. He currently presents with a two week history of what he describes as eczema around his ears and the back of his neck.
Trichomonas vaginalis is a protozoan flagellate that is a member of a triad group of organisms responsible for the majority of cases of vaginitis / urethritis.