RT Book, Section A1 McQueen, Alisa A1 Lelyveld, Steven A2 Schafermeyer, Robert A2 Tenenbein, Milton A2 Macias, Charles G. A2 Sharieff, Ghazala Q. A2 Yamamoto, Loren G. SR Print(0) ID 1105683481 T1 Common Parasitic Infestations T2 Strange and Schafermeyer's Pediatric Emergency Medicine, 4e YR 2014 FD 2014 PB McGraw-Hill Education PP New York, NY SN 978-0-07-182926-7 LK accessemergencymedicine.mhmedical.com/content.aspx?aid=1105683481 RD 2024/11/07 AB Virtually all organ systems are at risk for parasitic infestation, with symptoms depending on the system(s) involved. Some parasites only begin to produce symptoms months to years after the first exposure.Ascaris lumbricoides is the largest and most prevalent human nematode, with an estimated one billion cases worldwide. Albendazole (400 mg orally as a single dose) or ivermectin (150–200 μg/kg orally as a single dose) is curative.Enterobius vermicularis (pinworm) affects individuals of all ages and socioeconomic levels, with the most common presentation being that of a toddler or small child with anal itch. Scotch tape, placed sticky side to perianal skin when the child first awakens and viewed under low power may reveal the eggs, but may require repeated sampling.Trichuris trichiura (whipworm) lives predominantly in the cecum and can cause malabsorptive symptoms, pain, bloody diarrhea, and fever but is usually asymptomatic. A heavy worm burden may cause a colitis-like picture with rectal prolapse and anemia.The hookworms, Necator americanus and Ancylostoma duodenale, are one of the most prevalent infectious diseases of humans. The hallmark of hookworm infestation is the microcytic, hypochromic anemia of iron deficiency.The avian schistosome Trichobilharzia ocellata is spread by migratory birds to the freshwater lakes of the northern United States. The cercariae cause dermatitis, known as swimmer's itch.