LEC 4 - Larva Migrans Flashcards
Denotes that if a person is infected with the larva, the larva will start crawling in the tissues of the infected host, they migrate sa body ng infected host
LARVA MIGRANS
skin (epidermis)
Cutaneous Larva Migrans
visceral organs (soft internal organs)
Visceral Larva Migrans
a type of VLM, another effect of VLM, parasite migrated in the eyes of the host (periorbital region)
Ocular Larva Migrans
Site of Infections
Site of Infection
* Heart
* Lungs
* Digestive organs
* Reproductive organs
* Circulatory organs
* Excretory organs
not a typical part of the life cycle of the parasite, infected because the host was exposed to the parasite, the larvae will no longer developed to become adult
Accidental Host
also known as Toxocariasis, caused by Toxocara spp
Visceral Larva Migrans
if the periorbital region is involved
Ocular Larva Migrans
also known as creeping eruption or
ground itch
Cutaneous Larva Migrans
Etiologic Agent of CLM:
- Anyclostoma braziliense (cat hookworm)
- Anyclostoma caninum (dog hookworm)
- Strongyloides stercoralis – Larva Currens/Racing Larva
Rate of migration
5-15 cm/hr
associated with S.stercoralis, “Vietnam”
Cochin – China Diarrhea
Infective Stage of CLM
Filariform Larva
MOT of CLM
Skin penetration of larvae from soil
(CLM)
Etiology Most Common na CAT & DOG HOOKWORMS
Ancylostoma Braziliense
Etiology Less Common(CLM) - Dog Hookworms
- A.tubaeforme,
- A. caninum,
- A. ceylanicum,
- Uncinaria stenocephala
CLM Treatment
Self-limiting (larvae die in weeks to months)
Medication to relieve or alleviate pain and symptoms, dili contagious tho
VLM MOT
Ingestion if embryonated eggs from soil; ingestion of encysted larvae from animal organs
Can be harbored by ducks or rabbits (paratenic host)
(CLM)
Etiology Less Common - Animal strongyloidiasis
- S. myopotami
- S. papillosus
- S. westeri
(CLM)
Etiology Less Common - Cat, dog, pig roundworms
- Gnasthostoma spp.
- Gnathostoma spinigerum
(CLM)
Etiology Less Common - Cat, dog, poultry, & rodent whipworms
Capillaria spp.
(CLM)
Etiology Less Common - Cattle hookworm
Bunostomum phlebotomum
(CLM)
Etiology Less Common - Human hookworms
Ancylostoma duodenale
Necator americanus (ground itch)
(CLM)
Etiology Less Common - Human Strongyloidiasis
S. stercoralis (larva currens)
Infective Stage of VLM
Filariform Larva
VLM
Etiology MOST COMMON - Cat and Dog Nematodes
Toxocara canis
Toxocara catis
VLM
Etiology LESS COMMON - Dog/Cat
- Toxoscaris leonine
- Toxocara vitulorum
- Toxocara pleropodis
VLM
Etiology LESS COMMON - Racoon
Baylisascaris procyonis
VLM
Etiology LESS COMMON - Pig
Ascaris suum
VLM
Etiology LESS COMMON - Rare
- Angiostrongylus cantonensis
- Angiostrongylus costaricensis
- Anisakis spp.
- Capillaria hepatica
- Dirofilaria immitis
- Gnasthostoma spinigerum
- Gongylonema spp.
- Lagochilascaris
- Pseudoterranova spp.
– raw salt water fish, causes anisakiasis
(kapatid ni Anisakis)
Pseudoterranova spp.
VLM Treatment
Need treatment due to the severity of
symptoms
According to Panikers,
The larvae produce ____________, which develop into ____________ in the epidermis. With the movements of the larva in the skin, the lesion also shifts, hence the name ‘creeping eruption. Scratching may lead to secondary bacterial infection
itching papules; serpiginous tunnels
Strongyloides rare sa feces, because it is
ovoviviparous Rhabditiform larva
To identify hookworm from Strongyloides: (Fecal Cultures)
1.Harada Mori
2. Sand & Charcoal/Baermann
3. Koga Agar Plate Culture
abnormal tracks below the skin surface in the feet (30%)
o Stinging sensation upon penetration
o Larva starts migrating 1 week to several months after penetration
o Larvae forms tract 1-2 cm. beyond
CREEPING ERUPTIONS
o 2-4mm wide
o Erythematous (reddish), elevated, vesicular, itchy :
o Erratic Pattern (snake-line/serpiginous means wavy)
o Progresses 2mm to 2cm/day
MIGRATORY TRACT/ TRAIL
Anyone in contact with sand/soil in warm, moist, shady
areas:
o Sunbathers
o Fishermen
o Hunters
o Gardeners
o Constriction workers
o Children plating in sandboxes, beach
AT RISK GROUPS
Resolve with/without treatment, no long-term
complications Pruritic lesions → scratching → skin blisters wound open to secondary bacterial infection
Morbidity (self-limiting)
Mortality of Cutaneous Larva Currens
None
Diagnosis of CLM
o Physical examination & medical history
o Skin biopsy not necessary
o Peripheral eosinophilia
o Coherence tomography (imaging test to view larvae & remove them)
REMEMBER CLASS!!!
Eosinophilia – for parasitic infection
Basophilia – viral infections
Neutrophil – bacterial infections
TREATMENT of CLM - Without drugs
Self-heal
TREATMENT of CLM - With anti-helminthic drugs
- Albendazole (oral)
- Mebendazole (oral)
- Thiabendazole (topical)
- Ivermectin (oral)
TREATMENT of CLM - Supportive Therapy
- Antihistamines (relieve itching)
- topical corticosteroids (relieve inflammation)
- antibiotics (secondary infections)
TREATMENT of CLM - Surgical care
- cryosurgery (painful, requires multiple treatment)
- liquid nitrogen
- ethyl chloride spray
- carbon dioxide slush
CLM PREVENTION
o Avoid direct contact with contaminated soil: wear shoes on the beach, lay towels behind your backs on the sand, garden gloves
o Prohibit dogs & cats on beaches
o Deworm pets regularly
o Cover sandboxes when not in use to avoid animals defecating
- Disease affecting younger children (<5 years old)
- Symptoms due to antigens secreted by the migrating larvae
Visceral Larva Migrans
- Larvae migrate to lungs, liver, eyes, brain, muscles (visceral organs)
- Majority asymptomatic to gradual symptoms
Visceral Larva Migrans
- Symptoms of allergy & inflammatory response:
- Wheezing
- Breathlessness
- asthma-like
- cough
- itchy skin
- fever
- headache
- generalized weakness
- tiredness
- muscle pain
- seizures
Cardinal Signs of Inflammation
Rubor
Redness
Cardinal Signs of Inflammation
Calor
Heat
Cardinal Signs of Inflammation
Tumor
Swelling
Cardinal Signs of Inflammation
Dolor
Pain
Cardinal Signs of Inflammation
Funtio laesa
loss of function
*When migrating larval nematode invade the eye of the host
* More often in older children (5-10 y/0) & young adults compared to VLM (more often in young children 4-5 y/o)
* Symptoms of VLM may or may not be present
OCULAR LARVA MIGRANS
Eye involvement often leads to unilateral vision loss, cross eye called
strabismus
Etiologic agents of OLM
- Toxocara canis & T. cati (most common) → ocular Toxocariasis
- Baylisascaris procyonis – racoon
- Ancylostoma spp.
- Gnasthostoma spinigerum – swine
DIAGNOSIS OF OLM - Serology
ELISA (Enzyme Link Immunosorbent Assay)
using Toxocara excretory-secretory antigens
- Study of antigen and antibody
- Antibodies against Toxocara spp. (+ na-exposed ka sa Toxocara)
DIAGNOSIS OF OLM - Peripheral blood count
High eosinophilia (may be
absent on OLM)
- CBC count – not definitive, clue lang
- High eosinophil count – helminthiasis
DIAGNOSIS OF OLM - imaging
chest X-ray
DIAGNOSIS OF OLM - Histology
Encysted larvae in liver, lungs, brain, eyes
TREATMENT AND PREVENTION OF OLM - * Anti-helminthic drugs:
- Albendazole
- Mebendazole
- Diethylcarbamazine (DEC)
TREATMENT AND PREVENTION OF OLM - Supportive Therapy
Steroids during wheezing, inflamed tissues
- Removal of granulomas in the eyes
TREATMENT AND PREVENTION OF OLM - Prevention
- Careful child supervision
- Wash hands before eating
- Wash hands after playing with pets
- Cover sandboxes
- Regular deworming of pets
- Cook liver & other organ meats well before eating
calcification or scarring that can lead to blindness
granulomas
