- What is the identification of the object retrieved and submitted for identification?
The object submitted for identification was identified as a male Trichuris trichiura adult worm. The length was 35mm and characteristically for males the posterior end is coiled. Females can have about the same length as there is some overlap in size, but generally they can grow 5mm larger than the males (50mm in length). Also, the females will have a straight blunt posterior end. Females will produce between 2,000-10,000 eggs per day. The worms are nicknamed “whipworms” because of their characteristic shape that gives it the appearance of a “bull-whip”. They are Helminths belonging to the Nematode or Roundworm group. The other two groups within the Helminths are the Flukes or Trematodes, and the Tapeworms or Cestodes.
- Symptoms of infection are directly related to the organism burden. In small children what is a complication due to a heavy infection?
T. trichiura infections are generally asymptomatic. And when the symptoms are present, they are generally vague to mild. Generally, when there is a small worm burden there is the less chance that there will be any symptoms at all. However, a heavy worm burden will most likely produce symptoms that include painful bowel movements, diarrhea that may contain blood and mucous, and abdominal discomfort. Small children are more apt to have heavy infections and have symptoms. Small children with heavy infections are prone to rectal prolapse, suffer from anemia, and growth retardation. Treatment is effective in reversing the growth retardation.
- The ova/eggs produced by this organism have a distinct shape. How would you describe them?
The highly infectious ova/eggs produced by T. trichiura are distinct in their shape and appearance. They are generally oval/elongated with a football shape to them with prominent polar plugs at both ends. They are best detected in stool ova & parasite examinations utilizing Lugols Iodine in the formalin concentrate portion of the examination. The eggs will take up the iodine stain very well and are approximately 50-55um by 20-25 um (see image below).
- Adults are generally found in what part of the intestine?
Adults are found in the large intestine.
- Is this considered a nematode, trematode, or cestode?
This worm or Helminth is considered a nematode or roundworm.
- What is the treatment of choice?
The treatment of choice for T. trichiura infections is mebendazole or albendazole. Mebendazole is considered the first choice of treatment as it has been shown to be more effective than albendazole
Trichuris trichiura is mostly seen in the tropics and it is not uncommon for individuals to have co-infections with Ascaris lumbricoides or Hookworm. All three of these roundworms share the similar environmental requirements for development. Thus, the detection of any of these round worms should alert the technologist performing the ova & parasite examination that the possibility exists of a co-infection and the sample should be looked at thoroughly. Back when I first started in Microbiology working in an urban acute care facility which had a steady influx of migrants from Asia, it was not uncommon to find Trichuris trichiura and co-infections with Ascaris or Hookworm.