Intestinal nematodes 4 Enterobius vermicularis Morphology Pin worm

Intestinal nematodes [4]- Enterobius vermicularis

Morphology Pin worm - Seat worm * Small thread-like worm, whitish in color * 2 (alae) at the anterior end * Double bulbed esophagus

Morphology cont. Male 2 -5 mm Curved posterior end With one spicule Female 10 mm Pointed tail, 2 uteri full with eggs, Vulva at the junction of Ant. ¼ & post. ¾

Enterobius vermicularis intestine live Enterobiasis worm Geographical Distribution: cosmopolitan. Definitive host: man only Habitat: caecum and adjacent parts. Diagnostic stage: egg S: 50 X 20 µ ♀ S: plano-convex Plane Convex 10 mm has 2 layers long covered with outer sticky albuminous layer Eggs are found mainly on C: translucent perianal skin. C: rhabditiform larva

Mode of infection in Enterobiasis ♂ ♀ Female migrates during night Ingestion of eggs by: Autoinfection (hand to mouth) Contaminated food or drink Handling contaminated linen, clothing and articles. Rhabditiform larva Air-born in dust Retro-infection Eggs are infective in few hours

Pathogenesis and Clinical Picture n n Sticky egg laid in the perianal region at night causes Pruritis ani (Perianal itching). Pruritus ani leads to nervous irritability, hyperactivity and insomnia ( )ﺃﺮﻕ ﺑﺎﻟﻠﻴﻞ

Pathogenesis and Clinical Picture Granuloma formation Fallopian tube uterus urethra vagina appendix Appendicitis Urinary infection Vulva-vaginitis Pelvic peritonitis (Involuntary micturition) Intestine Secondary enuresis diarrhoea & abdominal pain

Diagnosis Clinically: pruritus ani at night. Laboratory: - Swabbing of perianal area to detect the eggs by: NIH swab Scotch adhesive tape - Adults may be seen in stool or anal area. - Eggs are rarely found in stool

N. I. H. swab The perianal area is swabbed in the morning before defecation with a cellophane paper tied to the tip of glass rod and inserted in a test tube. The cellophane is stretched on the slide and examined for eggs

Treatment Ø Ø Ø Albendazole. It should be repeated after 2 weeks. All members of the family should be simultaneously ( )ﻓﻰ ﻧﻔﺲ ﺍﻟﻮﻗﺖ treated. Application of white mercury oxide (white precipitate ointment) around the anus at night. Relieves itching, kills female worms coming out of the anus and prevents dispersal ﺗﺒﻌﺜﺮ of eggs. Ø

Epidemiology n n n Eggs become mature and infective in few hours. Pruritus leads to autoinfection. Prevalent in Egypt in children (5 -10 years) and old age (30 -35 years). (Biphasic age group) Prevention and Control • Mass treatment. • Personal hygiene and food protection. • Infected children should use tightly fitting trousers at night.

Intestinal nematodes [5]- Ascaris lumbricoides Giant Worm

Ascaris lumbricoides Ascaris: worm lumbricoides: earthworm-like Geographical Distribution: cosmopolitan 25 ♀ 20 cm cm ♂ Ascariasis Green salad contaminated with embryonated Ascaris eggs migration Definitive host: Man Habitat: lumen of small intestine Adult Ascaris worm Ascaris eggs in stool Diagnostic stage

Diagnostic Stage Ascaris egg in stool Infective Stage Embryonated egg X Fertilized egg Decorticated Egg contains 2 nd Unfertilized egg stage rhabditiform egg As fertilized egg larva 90 X 40 µ 60 X 45 µ but lacking long, narrow, oval, thick mamillations layer Rhabditiform Larva develops in ill-defined smooth Covered by the egg on the ground mamillations 1 st moult brownish ﺍﻷﺮﺽ immature Geohelminthic infection S S C C

Development of Ascaris inside body of infected human Larva is swallowed Migration stage Embryonated egg is swallowed 2 nd moult Rhabditiform larva Venous circulation 3 rd & 4 th moults Adult Ascaris in small intestine Intestinal stage

Pathogenesis and Clinical Picture During larval migration: Intense ﺷﺪﻳﺪ local inflammatory reaction around the larvae leading to pneumonitis. Eosinophilia Inflammatory cells Fever, cough, dyspnea ( ) ﺿﻴﻖ ﺍﻟﻨﻔﺲ and asthmatic attacks ( ) ﺃﺰﻣﺎﺕ ﺭﺑﻮ and oedema of lips

Pathogenesis and Clinical Picture Adult worms in the intestine: 1 - Digestive disturbances: Abdominal pain, colic, nausea, vomiting. Distension ( )ﺍﻧﺘﻔﺎﺥ or Dyspepsia ( )ﻋﺴﺮ ﻫﻀﻢ Due to production of anti-enzymes that interfere with protein digestion. Malnutrition and underdevelopment of children. 2 - Changes of the bowel movements: Diarrhoea or Constipation. Adult in the intestine

Complications ﻣﻀﺎﻋﻔﺎﺕ Traumatic effects: due to worm irritation by fever, drugs or anaesthesia Liver abscess Perforation, peritonitis Obstructive jaundice Appendicitis Intestinal obstruction

Volvulus a portion of the intestine twists around itself Intussusception a portion of the intestine enters into another portion

Ascaris worms coming out of the anus Ascaris worms enter the stomach to be vomited and may come out of external nares

Complications II-Toxic effects: caused by toxins of living or dead worms. Oedema of face, urticaria ( ) ﻃﻔﺢ ﺟﻠﺪﻯ , asthma ( ) ﺭﺑﻮ , insomnia ( ) ﺃﺮﻕ , nervous irritability and convulsions Asthma Urticaria

Complications III- Larvae in ectopic sites: Larvae go to patient’s viscera Venous blood Larvae penetrated intestinal Visceral larva migrans wall to blood stream

Diagnosis Clinically: Transient cough, dyspnea (1 -2 weeks). Vague ﻏﻴﺮ ﻭﺍﺿﺤﺔ abdominal manifestations. Laboratory: Sputum examination: streaks of blood, eosinophilia and larvae. Eosinophilia (20% - 7%) Eggs in stool. Adult in vomits, faeces. Radiologically: Plain X-ray of the lungs and Barium meal.

Plain X-ray of the lungs Normal lung Barium meal Lung shows scattered mottling ﺑﻘﻊ ﻣﺒﻌﺜﺮﺓ Loeffler’s syndrome

Treatment Albendazole OR Mebendazole In mixed infections: treat Ascaris infection first to prevent stimulating the worms to unwanted activity ﺗﺬﻫﺐ ﺍﻟﻰ ﺃﻤﺎﻛﻦ ﻏﻴﺮ ﻣﺮﻏﻮﺏ ﻓﻴﻬﺎ Surgical treatment of complications.

Epidemiology and Control Ascariasis is prevalent ( ) ﻣﻨﺘﺸﺮ at all ages, most common in preschool children. (Play and defaecate in soil) Sanitary disposal of human faeces. Nightsoil (human faeces & urine) should not be used as fertilizer food crops. Proper washing of vegetables eaten raw. Washing of hands before meals. Mass treatment.

Case A young youth suddenly complained of abdominal pain accompanied by constipation. He was admitted to the Emergency Department of El-NOUR Hospital. He was diagnosed as a case of intestinal obstuction. a- Enumerate helminths that may cause such condition. T. solium T. saginata D. Latum ? ? ? A. lumbricoides b- If the patient gave a history of eating Grilled Greenbeef, pork salad what is the possible parasite causing this condition? A. lumbricoides T. saginata T. solium c- Name the infective stage in this condition. S: 60 X 40µ Embryonated C: Scolex brownish Cysticercus Scolex with S: thick-shelled Bladder-like with Cysticercus bovis egg C: Larva cellulosae & mamillated 10 X 5 mm nohooks