Introduction


Mission Statement

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This web page, developed for an undergraduate parasitology course at Stanford, is dedicated to the parasite family Oesophagostomum, with an emphasis on species that infect humans. The lifecycle, classification, clinical manifestations, epidemiology, diagnosis, treatment, and prevention are all reviewed. In addition, there are a number of references, including other web links as well as historical and current journal articles to which the reader is referred for further interest.

Background


Oesophagostomiasis is a parasitic disease caused by species in the family Oesophagostomum. Although it is a well known parasite of goats, sheep, pigs, cattle, and monkeys, Oesophagostomum can infect humans. Endemic to regions in Ghana and Togo, this parasite has been termed the "nodule worm" because of the nodules that form on the intestines of the host it infects. Its life cycle is similar to that of the hookworm and thus it is believed that humans become infected after accidentally swallowing the stage 3 larvae in contaminated soil. The public health implications of this parasitic disease in endemic regions is important yet very under-researched. However, recent developments have provided improved treatment for Oesophagostomum infection, better biomarkers for epidemiological detection of the parasite, and better methods of diagnosis for this disease.

History

The first case of Oesophagostomum infection was reported by Brumpti in 1905. The patient was a male from the Omo river near Lake Rudolph in East Africa. The second case was described in more detail by Thomas et al. five years later in an article entitled "The Pathological Report of a Case of Oesophagostomiasis in Man," published in the Annals of Tropical Medicine. A detailed description of the clinical pathology was recorded (see "Case Study" below) which set the baseline to which future cases of the disease would be compared to. Throughout the 20th century, sporadic cases were reported in Brazil, Indonesia, and Uganda. However, the majority of infections seems to be endemic to areas in Ghana and Togo in West Africa. Because of better nutrition, sanitation, and health care, the disease is no longer as fatal as it once was. Oesophagostomiasis is still a serious health threat though and deserves serious attention.

A Historical Case Study
The following is a case study of the first presentation of Oesophagostomiasis by Brumpti.

The patient: A 36 year-old male from the Amazon state, Rio Purus. He was emaciated yet had well-developed muscles.
+Chief Complaints: Patient presented with acute dysentery and later became delirious.
+Outcome: Died within 3 days. The following post-mortem was observed.
+Gross: Pale and scanty subcutaneous fat; pale, brown muscle fibers; white fluid in pericardium; left side of heart enlarged; disteneded small intestine; surface of ileum, caecum, and colon were covered with nodules; liver and spleen were slightly enlarged; small intestine was studded with nodules for approximately 35 cm; 37 well-marked tumors identified, nodules were either soft and gray or small, hard, and opaque; nodules contained one worm at most; bowels were constricted; wall of S.I. was thin; dark-blue tumor in appendix; some worms found penetrating mesentery tissue; submucosa, intramuscular, and subperitoneal regions all had cysts; cysts lining the colon were yellow; small blood vessels were ruptured where worm had penetrate nodule.


Post-Mortem Pathology Plates
All plates borrowed from Brumpti and Thomas. "The Pathological Report of Oesophagostomiasis in Man." Annals of Tropical Medicine. 1910.

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Colon and small intestine tissue samples from patient infected with Oesophagostomum. Important to note are the nodules lining the lumen of the colon (right).


Worm protruding from nodule on the lining of the colon.


Outside covering of encysted worm.

Introduction
Classification
Life Cycle
Epidemiology
Clinical Manifestations
Diagnosis
Treatment
Links
References
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