TWO PROPOSED MODELS EXPLAINING EXCRETED URINE-ALBUMIN AETIOLOGY

1
Model selected by stepwise (AIC) logistic
regression controlling for sex, age, and location
URINARY SCHISTOSOMIASIS AND ZANZIBAR Schistosoma
haematobium infection, the cause for urinary
schistosomiasis, is responsible for a variety of
debilitating conditions, including urinary tract
pathologies (UTPs). Ultrasonography is commonly
used to detect UTPs, however new non-invasive,
rapid epidemiological assessment tools need to be
investigated. Objective To identify
associations between excreted urine-albumin, a
known proxy of S. haematobium infection in
children, and UTPs, as detected in ultrasonography

• FIELD WORK
• Three schools from Unguja Island (Chaani,
  Kinyasini, and Mwera) were surveyed (n 140
  children aged 9 to15 yr)
• A cross-sectional study of adult males (n 47)
  attending Chaani Health Centre was also conducted

• TWO PROPOSED MODELS EXPLAINING EXCRETED
  URINE-ALBUMIN AETIOLOGY
• School-aged children top/left
• Pairs of S. haematobium worms migrate to the
  vesical plexus and veins draining the ureters
• Egg production commences eggs pass from the
  lumen of blood vessels many penetrate the
  bladder mucosa being shed in the urine (blue
  arrows)
• Tissue damage and subsequent haemorrhage (red
  arrow) follow, increasing albumin concentration
  in urine

• URINE-ALBUMIN AND ULTRASONOGRAPHY
• In school-aged children, raised urine-albumin
  levels were found indicative of positive S.
  haematobium egg counts (OR29.5, plt0.001) not in
  adults, p0.58
• In school-aged children, prevalence of UTPs was
  found associated with positive S. haematobium egg
  counts (OR5.4, plt0.001) not in adults, p0.56

• Adults top/right
• Long term pathologies (particularly bladder
  lesions) are induced by high burdens and exposure
  to S. haematobium
• Through these lesions, albumin-rich blood-serum
  infiltrates the bladder (orange arrows)
• Infiltration leads to increase in urine-albumin
  levels without the direct influence of S.
  haematobium egg excretion and without causing
  haematuria

MORBIDITY Infection was found associated with
pain on urination in children (OR3.9, plt0.01)
and adult males (OR9.9, plt0.01)
Acknowledgements Dr Amadou Garba (SCI, Niger)
Mr Khamis Adulrahman Simai, Mrs Salma Suleiman
Seif, Mr Mahmoud Badru Ali and Mr Masoud Hassan
Juma (Unguja ultrasonographers) Health
Foundation, UK (DR, JRS) MRC (M-GB) Part of the
MSc in Modern Epidemiology, Imperial College
London (JCSF)