Schistosomiasis (Bilharzia)

B65.0/B65.1


DESCRIPTION

  • Disease manifestations caused by infestation by species of the genus Schistosoma.
  • Infestations with S. haematobium and S. mansoni are endemic in certain areas of South Africa.
  • Nematodes reside in venous plexus draining bladder wall (haematobium ) or intestine (mansoni ).

Complications include:

  • haematuria,
  • strictures,
  • dysuria,
  • hepatosplenomegaly,
  • cystitis,
  • portal hypertension,
  • calcifications in the bladder wall,
  • cirrhosis,
  • obstructive uropathy,
  • ascites,
  • bladder stones,
  • pulmonary hypertension,
  • intestinal perforation,
  • bladder cancer,
  • fistulas,
  • spinal cord granulomas with pressure effects.

DIAGNOSTIC CRITERIA

Clinical

  • Transient pruritic papular rash (swimmers itch) after exposure to cercariae in the water.
  • A few weeks after exposure:
    • fever,
    • wheezing,
    • chills,
    • hepatosplenomegaly,
    • headache,
    • arthralgia,
    • urticaria,
    • lymphadenopathy,
    • cough, and
    • eosinophilia.
  • Haematuria and dysuria.
  • Abdominal pain and diarrhoea often after ingestion of food.

Investigations:

  • Serology for schistosomiasis.
  • Urine and stools microscopy for viable eggs or rectal biopsy specimens.

GENERAL AND SUPPORTIVE MEASURES

  • Educate patient/caregiver on preventative measures.
  • Symptomatic and supportive treatment.
  • Avoid exposure to water contaminated by schistosoma.
  • Surgical intervention to correct or prevent complications.

MEDICINE TREATMENT

Acute Schistosomiasis

  • Prednisone, oral, 0.5 – 1 mg/kg daily for 5 days.

Start antihelmintic once acute symptoms have resolved:

  • Praziquantel, oral, 40 mg/kg as a single dose or in 2 divided doses on the same day.

Chronic Schistosomiasis

  • Praziquantel, oral, 40 mg/kg as a single dose or in 2 divided doses on the same day.
  • If given within 6 weeks of exposure, to be repeated in 4-6 weeks.

REFERRAL

  • Schistosomiasis with suspected complications following adequate therapy.