CN2 Cestodes Flashcards
In T. saginata, can man serve as an intermediate host?
No, defibitive host only
T. saginata adult worms inhabit in the jejunum and may live for how many yrs?
25 yrs
How long is taenia saginata?
4-10 m in length, we have 1,000 up to 4,000 proglottids
How long is the cuboidal scolex of taenia saginata?
1-2mm in diameter, and have 4 prominent acetabula
It is devoid of hooks or a rostellum and is attached to a short neck from which a chain of immature and gravid proglottid develop
Scolex of taenia saginata
Gravid proglottid are longer than wide in taenia saginata and the uterus is distended with ova and has
15 to 20 lateral branches
Spherical
30 to 45 micrometers
Brownish
Thick embryophore
Taenia saginata eggs
What is inside the egg shell of taenia saginata?
Oncosphere or embryo provided with three pairs of hooklets
In taenia solium, can serve as an intermediate host?
Yes, both definitive and intermediate host
Where does the taenia solium adult worm inhabit?
Upper part of the small intestine
How long is taenia solium?
2 to 4 m in length and may have 800 to 1,000 proglottids
Have 4 acetabula wc is smaller (1mm) and more spherical
Carries a cushion like rostellum with a double crown of 25-30 large and small hooks
Scolex of taenia solium
It has accessory ovarian lobe
No vaginal sphincter
Smaller number of follicular cells (100 to 200)
Gravid proglottid contains 7-15 lateral braches
Taenia solium
30-45 um
Thick brown striated embryophore surrounding a hexacanth embryo
T. solium
Which infection is more common in the Philippines?
Taenia saginata
In the life cycle of taenia saginata, upon ingestion of the eggs by the cattle, what is released?
Oncosphere
T. saginata: Where does the oncosphere actively penetrate and then enters a venule from which it is carried to different parts of the body?
Intestinal mucosa
T. saginata: once it enters a muscle fiber and it develops into an infective stage in 2 mos called
Cysticercus bovis
T. saginata: It is a ovoidal, milky white, about 10 mm in diameter and a single scolex invaginated into a fluid filled bladder
Cysticercus
The larva is digested out of the meat and the scolex evaginated to attach to the mucosa of the SI where it will become mature in how many weeks?
(T. saginata)
12 weeks
In T. solium the oncosphere penetrates the intestinal mucosa to encysts in muscles as
Cysticercus cellulosae
Oval, translucent with opaque invaginated scolex with four suckers and a circlet of hooks
Mature cysticercus
In taenia saginata, passage of proglottid causes:
Mild irritation at the site of attachment
Nonspecific symptoms such as epigastric pain, vague discomfort, hunger pangs, weakness, weight loss, loss of appetite and pruritus ani
T. saginata symptoms
Rarely tangled problems may result in
Intestinal obstruction
What is the most serious manifestation of taenia solium which is considered one of the most serious zoonotic disease worldwide?
Neurocysticercosis
What are observed when cysts are in the cortex?
Seizures
The subarachnoid form may lead to aggressive form called
Racemous cysticercosis
In the eyes, cysticerci may float freely where?
Vitreous humor
Vision is usually affected due to
Chorioretinitis and vasculitis
What can D. latum result in?
Hyperchromic, megaloblastic anemia with thrombocytopenia and leukopenia
What is the drug of choice for T. saginata infxns?
Praziquantel 5-10mg/kg as single dose
What is the criteria for cure in T. saginata?
1) recovery of scolex
2) negative stool exam 3 mos after tx
What is the drug of choice for T. solium infxns in INTESTINAL?
Praziquantel 5-10mg/kg
Niclosamide (not locally available)
What is the drug of choice for T. solium infxns in CYSTICERCOSIS - multiple parenchymal cystic lesions?
- Praziquantel at a dose of 50-75 mg/kg divided in 3 doses for 30 days
- Albendazole at a dose of 400mg twice daily for 8-30 days
Steroids are then given 4 hrs after last dose
- 80mg Prednisone
- 10mg IM Dexamethasone
Parenchymal forms presenting as cysticercotic encephalitis or those with massive parasitic infection are given high-dose corticosteroid therapy and mannitol in cases of
Increased intracranial pressure
In what temperature can kill the cysticerci?
Freeze at -20°C for 10 days
Surgical removal of lesions
Albendazole therap: 10-15mg/kg/day for 8 days
Subarachnoid cysticercosis
Surgical remobal of cyst
Ventricular cysticercosis
Treated surgically before Praziquantel or Albendazole bcs ocular inflam can’t be ctrlled by steroids
Ocular cysticercosis
What will you do to symptomatic cysts outside CNS?
Surgical removal
Common symptoms for D. latum
Nervous disturbances
Digestive disorders
Abdominal discomfort
Wt loss
Weak
Anemia
Vomiting
Colicky abdominal pain
Murphy’s sign
Cholangiopancreatography (cholecystitis)
T. saginata
Larval maturation of T. saginata in small intestine
12 weeks
Drug that may cause blindness in px w ocular cysticercosis
Praziquantel
