Parasite Clinical Vignettes Flashcards
A mother brings her restless 3-year-old daughter to your office. The daughter has not slept well for several days and yesterday mom noticed her scratching near the anal opening. You examine the child, confirm the perianal inflammation, and notice several small, white worms in the perianal skin folds (a). You apply an adhesive paddle to the area and recover organisms. Microscopic examination of the adhesive reveals eggs that are flattened on one side (b). What’s your diagnosis?
Enterobius vermicularis
**pinworm: Egg flattened on one side
A 30-year-old woman from Mobile, Alabama discovered a worm in her stool. She took the specimen to her doctor, reporting no symptoms or international travel.Because of the high likelihood that she had more than one worm, she was treated with albendazole. Five additional worms showed up in her stools following treatment. What’s your diagnosis?
Ascaris lumbracoides
**giant round worm
A 5-year-old boy from a small town just outside of Jackson, Mississippi presents with epigastric pain, nausea, and vomiting. He shows pitting edema and ascites. Stool examination reveals blood and leukocytes. Lab findings include 18% eosinophilia and anemia (hematocrit 24%). A stool exam reveals numerous helminth eggs (see below). What’s your diagnosis?
Ancylostoma duodenale
- *hookwork disease
- *anemia, ascites, edema, eosinophilia, GI symptoms
A 55-year-old man was admitted to an Ohio emergency room for headache, fever, general muscle aches, and weakness. Laboratory work-up on his blood specimen revealed significantly elevated eosinophilia. The patient reported that he had gone on a camping and hunting trip the month before in Ontario, Canada. He shot and killed a black bear and brought several pounds of meat home. In the weeks before onset of symptoms, he ate several meals that included bear meat. Figure A shows what was seen in a stained section of muscle biopsy taken from the deltoid area of his left arm. Portions of the remaining bear meat were sent to CDC for examination. A 100 g portion of meat was ground and digested in an acidic pepsin solution. Examination of the sediment revealed small numbers of the objects shown in Figure B. What’s your diagnosis?
Trichinella spiralis
**infects muscle
A 32-year-old man visited the Philippines for a month, traveling throughout the major islands on nature tours. Nine months after his trip, he visited his physician due to a small lump in his groin.He did not have discharge nor discomfort from the nodule. The patient was referred to an infectious disease physician who ordered a blood film examination; the patient’s blood was drawn during evening hours. The object in Figure A was seen on a Giemsa stained thick smear (magnification 400×), and the object in Figure B was observed on a Giemsa stained thin smear (magnification 500×). The objects measured approximately 215 micrometers long. What’s your diagnosis?
Wuchereria bancrofti
**lymphangitis, elephantiasis
You volunteer in a clinic just outside of San Jose, Costa Rica. A 10- year-old boy presents with a 4 cm nodule on his head. The nodule is firm but weakly attached to the subcutaneous tissues. The clinic physician performs a nodulectomy and the nodule is fixed, processed, and stained with H&E. The histopathology slide is shown on the right. What’s your diagnosis?
Onchocerca volvulus
**diagnosed by finding microfilaria near nodules
As you walk along a street in Lagos, Nigeria you notice a man winding what appears to be a string out of the swollen foot of another man. Upon closer inspection, it appears that the string is a worm. What is your diagnosis?
Dracunculus medinensis
**diagnosed by finding the female worm inside a skin lesion
A 39-year-old middle school biology teacher collected shells as souvenirs for her students from her summer vacation in Thailand and the Philippines. She collected a large number of shells from beaches, lakes, rivers, and streams of both countries (A and B). After returning from her trip, she went to a local health clinic for mild to moderate episodes of intestinal cramping. Within the last two to three weeks, she indicated that the cramping became more severe and frequent. She also stated that she had occasionally seen blood in her stool and that her abdomen was slightly bloated. She submitted a stool specimen for examination. Eosinophilia was noted in her bloodwork.What ‘s your diagnosis?
Shistosomiasis
A 30-year-old man who comes to your office after finding the object shown below in his stools. The object was actively moving and caught his eye. He expresses concern that a portion of his intestines has sloughed off. He has no physical complaints. A brief history reveals that he works on a dairy farm. Given the size and shape of this object, and the man’s profession, what is your diagnosis?
Taeniasis
A 40-year-old farm hand from Chihuahua, Mexico had experienced several mild seizures and blurred vision for a week before going to a local clinic. During the examination the clinic physician noticed something floating in the anterior chamber of his left eye. What’s your diagnosis?
Taenia solium larvae
**Cysticercosiscysticerci in the eye can cause retinitis or uveitis.
