Nematodes (round worms)

Question 1

Types

Answer 1

1. Hookworm (necator americanus)
2. strongyloides stercoralis
3. ascariasis (garden worm)
4. Thread worms (enterobius vermicularis)
5. whipworm (trichuris trichirua)

Question 2

Hookworm

Answer 2

Necator americanus

• SE asiam india
• small worms attach to upper GI mucosa, causing chronic bleediing and iron-deficiency with devastating effects on childrens and moters
• eggs excreted in faeces and hatch and soil

INvestigations - stool microscopy

treatment - mebendazole mg/12hr for 3d

Question 3

Strongyloides stercoralis

Answer 3

• transmitted via skin, it causes migrating urticaria on legs and trunk
• pneumonitis, enteritis/malabsoprtion (chronic diarrhoea/abdominal pain)
• worms may take bacteria into the blood causing septicaemia + meningtiis

investigation - stool microscopy, serology or duodenal aspiration

treatment- ivermectin 0.2mg/kg/24h PO for 48 hours

Question 4

Ascaris lumbricoides

Answer 4

• 3 finely toothesd lips
• transmission: faecal-pral
• migrates through the liver and lungs, settling in the small bowel
• often asymptomatic - GI obstruction/perforation

investigations- stool microscopy (ova stain orange in bile); worms on barium x-ray; eosinophillia

Treatment - mebendazole (100mg/12h PO for 3d ), albendazole (400mg PO once), ivermectin (150-200ug/kg PO once)

Question 5

threadworms

Answer 5

• enterobius vermicularis
• cause anal itch as they leave the gut to lay eggs on the perineum

investigations- apply stick tape there to identify eggs micrsocopically

treatment - mebendazole (100mg/12h PO for 3d). treat the whole family. Hygiene is more important that drugs as adult worms die after 6 weeks.

Question 6

Whipworm

Answer 6

• trichuris trichiruia
• causes non specific abodminal pain, dysentry and sometimes rectal prolapse

investigations- eggs ins tool

treatment - mebendazole 100mg/`12h for 3 days