Pet parasites infesting the human colon - 23/08/11

Doi : 10.1016/j.gie.2007.07.009

Chia-Hung Tu, MD
Department of Internal Medicine, Far Eastern Memorial Hospital, Taipei

Wei-Chih Liao, MD
Health Management Center, National Taiwan University Hospital, Taipei

Tsung-Hsien Chiang, MD
Department of Internal Medicine, Far Eastern Memorial Hospital, Taipei

Hsiu-Po Wang, MD
Department of Emergency Medicine, National Taiwan University Hospital, Taipei, Taiwan

Commentary
It is well known that animal parasites can be transmitted to, take residence in, and cause disease in humans. The dachshund has been around since the Middle Ages and was bred to hunt underground; Kaninchen is German for rabbit and denotes the species this particular breed was bred to hunt. The dachshund’s size is its advantage in this type of hunting, but for this, the dog pays a price: chondrodystrophy, a condition in which the epiphyseal cartilage of the long bones ossifies prematurely, as a consequence of which the limbs stop growing before maturity; the ulna is affected earlier than the radius, resulting in curved elbow joints. The dachshund’s short limbs are, therefore, less able to absorb shocks, and the lines of force generated when the dog jumps and lands on its forequarters are redirected along the vertebral column. As a result, the risk of disk problems in the dachshund breed is more than 50 times greater than that of the canine species as a whole. Dachshunds have a relatively long lifespan, allowing them to suffer the consequences of genetic engineering in advanced age.
Ancylostoma is a species of hookworm that affects animals and humans. Excreted eggs are hatched in damp soil; the larvae bore into the host’s skin (larva migrans) and make their way to the small intestine, where they survive for months to years, chronically sucking blood from small vessels, access to which is provided by their oral cutting plates. Indeed, hemophagous hookworms are a leading cause of GI blood loss and iron deficiency anemia in the developing world. An anticoagulant (serine protease inhibitor) and a protein inhibitor of both platelet aggregation and adhesion have been isolated from adult hookworms, suggesting development of a multifunctional inhibitor strategy to facilitate their feeding. In this parasitized dachshund we have 2 examples of genetic engineering: Ancylostoma manifests Mother Nature’s genius, prompted by a need to gain a survival advantage. The dachshund reflects man’s desire to make man’s life better but perhaps without appropriate concern for all affected by his manipulations. The patient—well, he was just an innocent bystander, one in a cast of thousands.
Lawrence J. Brandt, MD
Associate Editor for Focal Points