Question

HELMINTH GENUS NAMES TO MATCH TO THE CASE STUDY:      

Taenia Ascaris Enterobius

Schistosoma Trichinella

Case 1:

A 4-year-old female arrived at the emergency department with abdominal pain, vomiting and a 3-day history of diarrhea. She also exhibited tachycardia, bloating with no bowel sounds, and a palpable mass in the area of the right ileum. An X-ray of the area revealed air fluid levels and the shadow of roundworms in a “whirlpool” image. The ileum was nearly obstructed, and the patient underwent laparotomy to remove the worms. A mass of white worms was removed, with the smallest measuring 16 cm in length and the largest 35 cm in length.

After surgery, the patient was given hydration and antibiotics for 72 hours. Once peristalsis restarted, the patient was placed on albendazole for 3 days and was told to return for another round of albendazole in 6 weeks.

Genus Name of Causative Agent ___________________________________

Mode of Transmission to the adult ________________________________________________________

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Case 2:

A 30-year-old man had made three trips to India between August 2012 and May 2013. On each trip, he had stayed for several weeks with an assigned host family. After returning from the third trip, the man noticed a subcutaneous nodule on his left neck. The nodule was painless. It was also at this time the he reported having a little nausea several hours after eating. When he noticed “noodle-like” material expelled in his feces, he sought medical attention. A subsequent collection of a stool sample revealed small white segments of gravid proglottids. A physical examination revealed other subcutaneous lesions that were palpable in the lower jaw, neck and lateral abdomen. A biopsy of one of the lesions from his abdomen revealed a white cyst that showed characteristics of a scolex and an invaginated neck. The patient was diagnosed with disseminated cysticercosis. He was treated with albendazole and oral prednisone for two weeks in an attempt to expel the worm or worms.

Genus Name of Causative Agent ___________________________________

Mode of Transmission to the adult ________________________________________________________

_________________________________________________________________________________________________________________________________________________________

Case 3:

A 39-year-old middle school biology teacher collected shells as souvenirs for her students from her summer vacation in Thailand and The Phillipines. She collected a large number of shells from beaches, lakes, rivers and streams in both countries. After returning from her trip, she went to a health clinic with complaints of mild to moderate episodes of intestinal cramping. The cramping had become more severe and frequent within the last two weeks, and her abdomen felt bloated. She went to the clinic after noting a small amount of blood in her stool.  

An examination revealed that the patient was slightly febrile and exhibited an elevated eosinophil count. A stool sample was collected and sent for analysis. The examination revealed eggs that measure 60 x 90 micrometers. No adult worms were found in the stool sample, but generally the adult worm is a fluke with separate male and female forms. The worms are generally yellow to brown in color and can measure 8-28 millimeters in length.

The patient was placed on praziquantel for 2 days.     

Genus Name of Causative Agent ___________________________________

Mode of Transmission to the adult ________________________________________________________

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Case 4:

In December of 2016, a celebration gathering of friends and family members dined on a variety of pork dishes. The pork meat had come from a domesticated wild boar raised and slaughtered on a private farm in Northern California. One of the pork dishes was in the form of a traditional Laotian dish in which the meat is served raw.

In January of 2017, one of the dinner attendees presented to a hospital with fever, myalgia, abdominal pain, vomiting and diarrhea. The patient reported that four other friends and family members had been evaluated at area hospitals with the same symptoms. Bloodwork revealed 10% eosinophils. A subsequent IgG antibody test detected antibody against the suspected pathogen.

Contact information was obtained for most of the people that had attended the celebration. Overall, 36 of the attendees exhibited symptoms of fever, muscle aches, bloating, vomiting and diarrhea. Nine people were hospitalized: six with indication of damage to the myocardium, two with acute kidney injury and one with blood sepsis.

Samples of the raw pork were taken from leftover meat that had been frozen and were analyzed microscopically. Cysts containing spiraled juvenile worms were found in the frozen boar meat. The farmer who raised the boar was asked if the farm had infestations of rats or mice.

The patients were placed on albendazole. Those hospitalized required prolonged treatments.

Genus Name of Causative Agent ___________________________________

Mode of Transmission to the adult ________________________________________________________

______________________________________________________________________________________________________________________________________________________

Case 5:

A 12-year-old male was seen at a gastroenterology clinic following 2 weeks of abdominal pain. The patient also reported an itching sensation around the perianal region. The abdominal pain was diffuse (not localized) but had worsened in the prior 5 days. The pain was pronounced enough to prevent the patient from attending school. He was evaluated for appendicitis, which was ruled out. A follow-up endoscopy was performed.

During the endoscopy procedure, small, mobile worms were noted in the ascending colon. Two worms were collected: a male of 2.5 mm in length and a female of 10 mm in length. Both worms had a cuticle at the anterior end and a pointed tail. Eggs were also obtained, measuring 50-60 micrometers in size.

Usually, abdominal pain does not accompany this type of infection. In this case, the pain was attributed to an over-use of NSAIDS. Since this worm generally does not enter the stool stream, examination of the stool is unreliable for detecting the worm or eggs. An application of transparent tape to the perianal region 2-3 hours after the patient has gone to sleep is recommended to submit for a microscopic examination.

The patient and his family were given a dose of albendazole with a repeat dose to follow in 2 weeks.

Genus Name of Causative Agent ___________________________________

Mode of Transmission to the adult ________________________________________________________

Answer 1

Case 1. Genus name of causative agent: Ascaris.

Mode of transmission to the adult: Transmission of Ascaris occurs when infected eggs are ingested from the soil contaminated with human faeces or by consuming uncooked produce contaminated with soil containing infective eggs.

Case 2. Genus name of causative agent: Taenia

Mode of transmission to the adult: Taeniasis is acquired by humans through the ingestion of the parasite' larval cysts in undercooked and infected beef. Human tapeworm carriers excrete tapeworm eggs in their faeces and contaminate the environment when they defecate in open areas. Humans can also be infected with tapeworm eggs due to poor hygiene (via the fecal-oral route) or ingesting contamminated food or water.

Case 3. Genus name of causative agent: Schistosoma

Mode of transmission to the adult: The parasitic infection is transmitted to humans when the larval forms of the parasite released by freshwater snailspenetrate the skin during contact with infested water. Also people become infected when people suffering from the schistosomiasis contaminate freshwatersources with their excreta containing parasite eggs which hatch in water.

Case 4. Genus name of causative agent: Trichinella

Mode of transmission to the adult: Transmission of Trichinella spiralis only occurs through the consumption of animal meat (rodents,bears, dogs, wild boar and even horses) infected with the pathogenic cysts encasing its larvae.

Case 5. Genus name of causative agent: Enterobius

Mode of transmission to the adult: Pinworms are transmitted by diret transfer of infected eggs by hand from the arse to the mouth of the same or another person. Another indirect mode of transmission is through bedding, clothing, food or other articles. Spreading of this parasite is facilitated by overcrowding.