UNIT 2 (part three) Flashcards
The worms may be present as parasitic in the host or free living in the soil.
strongyloides stercoralis
measures 1 mm in length with curved posterior end and carries two spicules
male
measures 2.5 mm in length with straight posterior end.
female
term used when parasite never reaches soil , it re-enters the host
auto-infection
favorable condition of strongyloides
soil
non favorable conditions of strongyloides
auto-infection
The patient complains of _______ _______. Larvae in the lungs may cause ________.
mucoid diarrhea
pneumonia
organs affected by strongyloides may be:
- liver
- heart adrenals
- pancreas
- kidneys
- CNS
diagnosis of strongyloides
Detection of rhabditiform larvae of strongyloides in stool.
is a small white worm with threadlike appearance. The worm causes enterobiasis. Infection is common in children.
enterobius vermicularis
treatment of strongyloides
Thiabendazole: 25 mg/kg (twice daily) for 3 days.
enterobius vermicularis is otherwise known as?
pinworm or threadworm
measures 5cm in length. The posterior end is curved and carries a single copulatory spicule.
male
measures 13 cm in length. The posterior end is straight.
female
enterobius vermicularis mode of infection is by
- By direct infection from a patient (Fecal-oral route).
- Autoinfection
- Aerosol inhalation from contaminated sheets and dust.
where do female enterobius’ glue their eggs after the male dies?
peri-anal skin
second species of enterobius
enterobius gregorii
clinical presentation of enterobius:
- allergic reaction around anus
- nocturnal itching
- enuresis
diagnosis of enterobius
- Eggs in stool
- Peri-anal swab
egg hatches and larva migrates to the rectum is called?
retroinfection
treatment of enterobius
Mebendazole or Piperazine.
definitive host of gnathostoma spinigerum:
- pigs
- cats
- dogs
geographic distribution of gnathostoma
asia (esp thailand and japan) and mexico
The nematode (roundworm) _________ __________, the rat lungworm, is the most common cause of human eosinophilic meningitis.
Angiostrongylus cantonensis
definitive hosts of Angiostrongylus cantonensis
rats and freshwater prawns
This group includes the filarial worms, the guinea worm (Dranculuculus medinensis) and Trichinella spiralis.
tissue nematodes
have complex life cycles involving a developmental stage in an insect vector. They require an arthropod vector for their transmission. The worms inhabit either the lymphatic system or the subcutaneous tissues of man.
filarial worms
This is a parasite of lymph nodes and lymphatic vessels- causing tymphatic filariasis.
wuchereria bancrofti
mode of transmission of whuchereria bancrofti
by the bite of the arthropod
disease caused by whuchereria bancrofti is called?
bancroftian elephantiasis
symptoms of whuchereria:
- lymphangitis
- lymphedema
- fever
- headache
- myalgia
6.hydrocele - chyluria
treatment of whuchereria
Diethyl carbomazine (DEC): 2 mg/kg 3x daily for 2 weeks.
of the lower limbs is common in Ethiopia. Silicon, aluminium and iron particles in the red clay soil are absorbed through skin abrasions in bare footed persons. The mineral particles cause obstruction of the lymphatics.
non-filarial elephantiasis
non-filarial elephantiasis is otherwise known as?
podoconiosis
vector of brugia malayi
mosquito
The typical vector for Brugia malayi filariasis is mosquito species from the genera?
mansonia and aedes
diagnosis of brugia malayi
blood collection
stain to use for thick smear for brugia malayi?
giemsa
hematoxylin
eosin
river blindness, similar to whuchereria bancrofti
onchocerca volvulus
Similar to that of Wuchereria bancrofti.
male of onchocerca volvulus
measures 30-50 cm in length. It is present inside of a fibrous nodule (onchocercomata or onchocerca tumor).
female of onchocerca volvulus
intermediate host of onchocerca volvulus
black fly
definitive host of onchocerca
humans
onchocerciasis includes symptoms such as:
- Skin fibrous nodules (onchocercomata)
- Skin hypo- or hyper- pigmentation
- Elephantiasis of the external genitalia
diagnosis of onchocerca volvulus
skin biopsy
treatment of onchocerca volvulus
Ivermectin 50 mg/kg bodyweight, given every 6-12 months
prevention of onchocerca volvulus
- Vector control
- Mass treatment
- Establishment of villages away from Simulium breeding places
- Use of repellents
- Protective clothing
otherwise known as mango fly
loaloa
lowa lowa is an?
eye worm
insect vectors of loaloa:
mango flies of chrysops
chrysops silacea
chrysops dimidiata
Loiasis is endemic in?
central and west equatorial africa
loaloa resides where in the human body?
subcutaneous tissue (adult) and eye microfilariae (blood)
diagnosis of loaloa
- Detection of microfilaria in peripheral blood, urine, sputum, CSF - stained with Giemsa or unstained.
- eosinophilia
treatment of loaloa
DEC, 6 to 10 mg per kilogram per day for 2 to 3 weeks
causes dracunculiasis.The infection is endemic to Asia and Africa: India, Nile Valley, central, western and equatorial Africa.
drancunculus medinensis
intermediate host of drancunculus medinensis
cyclops
definitive host of dracunculus medinensis
humans
clinical feature of dracunculus medinensis
female releases histamine-like component that triggers allergic reactions
diagnosis or dracunculus medinensis:
- Clinical: Observation of blister, worm or larvae
- Histologic features of subcutaneous sinus tract
- Eosinophilia and radiographic evidence
treatment of dracunculus medinensis
Surgical excision when the worm is in the leg Niridazole (Ambilhar) or DEC
mansanella species:
- M. ozzardi
- M. perstans
- M. streptocerca
are unsheained and measure i ou-205 um in stained blood smears and 200-255 um in 2% formalin. The tail tapers to a point and the nuclei end well before the end of the tail. The end of the tail is also bent in a small hook-like shape. Microfilariae circulate in blood.
mansanella ozzardi
are unsheathed and measure 190-200 um in stained blood smears and 180-225 um in 2% formalin. The tail is blunt and nuclei extend to the tip of the tail. Microfilarice circulate in the blood.
mansanella perstans
are unsheathed and measure 180-240 um. The tail is been into a hook-like shape and the nuclei extend to the end of the tail. Microfilariae are found in skin and do not circulate in the blood.
mansanella streptocerca
where do mansanella species reside in the human body?
skin or dermis also reaches peripheral blood
