I. Definition ,The most common intestinal parasites in the world , ascariasis is caused by a roundworm , Ascaris lumbricoides .
Infection occurs by ingestion of Ascaris eggs contained in contaminated water or vegetables. The eggs then pass through the lungs before being swallowed by the fever and cough and possible abdominal pain, issue of worms in the stool or vomiting.

This is a striped roundworm nematodes class up to 15 cm . Especially in rural areas.

II . Body type:

A. Adult :

* Ver pinkish white, elastic
* Mouth with 3 lips cutting
* Internal Organization polymyaire type large muscle cells

* The male is 15-20 cm long , with a diameter of .3 cm , rear end in stick,
2 spicules brownish

* Female 20-25 cm , diameter 0.5 cm , straight rear end , vulva ventrally to third prior

B. Egg:

* Ovoid , double hull, the outer is brown and hummocky , internally smooth , yellowish , non fertilized egg to
* Dimensions : 50-70 x 45-50 microns microns
* Frequency of unfertilized eggs and atypical

III . Life cycle :

* This is a direct cycle. The definitive host is man,

* Adult worms in the small intestine , feeding on intestinal chyle , and fecal excretion of eggs (about 200,000 / female / day). Lamaturation eggs is done in the external medium in 2-6 semainesselon conditions . Oral contamination is by ingestiond'oeufs

* Release of eggs in the intestine and migrationlarvaire transviscérale : crossing the intestinal mucosa, and sedirigent to the portal system and passage through the liver ( 3- 4days reached ) .

* Passage through the right heart and the lungs and passes through the wall of the alveoli with in 8 days,

* Mutation eggs and raising of the respiratory tree , pharynx and
swallowing and arrival to the digestive tract ;

* This is an entero - pulmonary migration

* Adult Stadium obtained in 2 -3 months

* Lifespan: 12 -18 months ;


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IV . Epidemiology:

* The roundworm parasite 's reservoir is man , cosmopolitan, endemic in hot and humid countries of the third world (cause infant demortalité ), the prevalence can reach 70 % of children.

* The global prevalence outside Europe: 22 % in 1987
The prevalence in temperate countries : 1%

* The embryonnement eggs is on the ground and survival estprolongée so LBS tank (in highly endemic area : 100oeufs / g of soil)

* The eggs are removed by human waste , so related condition faeces
human,

* Contamination of drinking water , hands and vegetables contaminated with embryonated eggs ( dirty hands )
* Resistance eggs in the external environment :
- 5 years in the presence of oxygen
- Resistance to cold, heat and antiseptics
- Eggs killed by extreme heat , direct sunlight
* Ingestion of plants carrying eggs or eggs lying on dirty hands .
Éclosionde egg, larval tissue migration through 3 weeks lespoumons , dating bronchi, swallowing at the crossroads aero digestifet migration to the intestine, maturation and egg laying eliminated dansles stool.
* Serious illness in children and infants.

V. Clinic :

Clinical Lesmanifestations are due to larval migration is unephase inconstant . The start takes place after an interval of 3 to 8 joursaprès contamination by fever, cough , Loeffler's syndrome , and dyspnea .

A. Phase invasion :

This phase corresponds to the pulmonary passage of larvae. It lasts from 2 to J J 8 .
Its pathogenesis is characterized by a toxic action , traumatic and bacteriological allergic reaction , mechanical .
Lesyndrome Loeffler consists of fever, dry cough, unedyspnée , coughing , allergic reactions and transient opacitéradiologique to sharp edges .
Loeffler's syndrome is pathognomonic of ascariasis .
The examensanguin is eosinophilia ( 3,000 / mm3 = 3 G / L) with maximum someValue to J +21 . One can find a leukocytosis ( -10 to 20,000 / mm3 = 10-20 G / L).

B. Phase Status : State :

It is characterized mainly by digestive disorders such as nausea and alternating constipation and diarrhea.
Cettesymptomatologie is linked to the presence in adult tubedigestif . Clinical signs depend on the number of worms and destraumatismes caused.

In addition to gastrointestinal disorders ( accelerated transit , vomiting) , there appear troubles nerveuxà type of irritability, insomnia , nocturnal sialorrhea , and desmanifestations
allergic (pruritus , angioedema ) .

Spoliation (4 g / worm) can lead to thrive under heavy infestation

C. Evolution:

Descomplications can occur regardless of the number of worms : aberrant migration , intestinal obstruction, peritonitis perforationet secondary sepsis.

VI . diagnosis:

A. During the invasion phase :

1 Diagnostic orientation . Radiopacity , eosinophilia and leukocytosis .

2 Direct diagnosis . Possible

3 Indirect diagnosis . Searchable serum antibodies

B. During the state phase

1 Diagnostic orientation . Fortuitous detection by examination of the small intestine after barium

Direct 2.Diagnostic : coprology highlights oeufscaractéristiques hummocky 70 X 40 microns , non eyed the issue, frequency of abnormal eggs. With the possibility of externalizing versadultes in stools and vomiting .

3 Indirect diagnosis . Unusable

VII . treatment:

Always treat because of the risk of complications.

A. Medication pest :

1 Molecules ascarifuges . Piperazine salts Nematorazine ®

. 2 Molecules ascaricides and nematicides :
* Levamisole Solaskil ® ,
* Pyrantel Combantrin ® , used in pregnant women

3 benzimidazoles . :
* Flubendazole Fluvermal ® ,
* Albendazole Zentel ® hospital and DOM TOM ,
* Mebendazole Vermox ® hospital.

B. Other therapeutic :

Surgery is used in case of complications.

C. Therapeutic monitoring :

Complete healing is achieved with appropriate treatment. The coprology occurs after 1 month of treatment .

D. Prophylaxis:

1 general prophylaxis . :

* Fight against the faecal peril
* Sanitary Measures ,
* Prohibition of spreading human fertilizer ,
* Water hygiene
* Mass treatment considered

2 individual prophylaxis . Hand hygiene, hygiene water ( boiling ) , washing vegetables [center] .
conclusion

The roundworm is the most common parasitic disease in the world . It is related to the faecal peril .

After oral ingestion , a mature egg, larva crosses dugrêle wall wins the liver and lungs before finishing Lalumière evolve in the small intestine .

- In Löffler syndrome marquantparfois phase larval migration can succeed and exceptionally troublesnerveux of surgical complications.

- The diagnosis is based on the observation of eosinophilia , laprésence specific antibodies early in infection puisdeux months after issuance
eggs in the faeces.