INTESTINAL WORMS

Intestinal worms enter the human body through ingestion of the worm eggs in food or water via dirty hands or through injured skin when walking barefoot. Examples include:

TYPE OF
INFESTATION
FEATURES
Ascariasis
Ascaris
lumbricoides

(round worm).
Infests small
intestines
  • Oro-faecal transmission
  • Usually few or no symptoms
  • Persistent dry irritating cough
  • Patient may pass out live worms
    through the anus, nose, or mouth
  • Pneumonitis- Loeffler’s syndrome
  • Heavy infestations may cause
    nutritional deficiencies
  • Worms may also cause obstruction
    to bowel, bile duct, pancreatic duct,
    or appendix
Enterobiasis
(threadworm)
Enterobias
vermicularis
  • Transmitted by faecal-oral route
  • Mainly affects children
  • Intense itching at the anal orifice
Hook worm
Caused by
Necator
americanus and
Ancylostoma
duodenale
  • Chronic parasitic infestation of the
    intestines
  • Transmitted by penetration of the
    skin by larvae from the soil
  • Dermatitis (ground itch)
  • Cough and inflammation of the
    trachea (tracheitis) common during
    larvae migration phase
  • Iron-deficiency anaemia
  • Reduced blood proteins in heavy
    infestations
Strongyloidiasis
Strongyloides
stercoralis
  • Skin symptoms: Itchy eruption at
    the site of larval penetration
  • Intestinal symptoms e.g. abdominal
    pain, diarrhoea, and weight loss
  • Lung symptoms due to larvae in the
    lungs, e.g. cough and wheezing
  • Specific organ involvement, e.g.
    meningoencephalitis
  • Hyperinfection syndrome:
    Occurs when immunity against
    auto-infection fails, e.g. in
    immunosuppressed cases
Trichuriasis
Whip worm
Infests human
caecum and
upper colon
  • May be symptomless
  • Heavy infestation may cause bloody,
    mucoid stools, and diarrhoea
  • Complications include anaemia and
    prolapse of the rectum

Differential diagnosis

  • Other causes of cough, diarrhea
  • Other causes of intestinal obstruction and nutritional deficiency
  • Loeffler’s Syndrome
  • Other causes of iron-deficiency anaemia

Investigations

  • Stool examination for ova, live worms or segments
  • Full blood count

Management

Roundworm, threadworm, hookworm, whipworm

  • Albendazole 400 mg single dose
    Child <2 years: 200 mg
  • Mebendazole 500 mg single dose
    Child <2 years: 250 mg

Strongyloides

  • Albendazole 400 mg every 12 hours for 3 days
  • Or Ivermectin 150 micrograms/kg single dose

Prevention

  • Proper faecal disposal
  • Personal and food hygiene
  • Regular deworming of children every 3-6 months
  • Avoid walking barefoot