Pathogens causing diarrhoea among Bangladeshi children with malignancy: Results from two pilot studies

Area of Science:

• Paediatric Oncology
• Infectious Diseases
• Gastroenterology

Background:

• Diarrhoea is a common symptom in paediatric cancer patients, often multifactorial.
• Causes include underlying disease, therapy-induced immunosuppression, malnutrition, and infections.
• The exact cause of diarrhoea is frequently unknown, with parasites being common culprits.

Purpose of the Study:

• To identify and characterize the pathogens responsible for diarrhoea in children with cancer in Bangladesh.
• To compare the effectiveness of different diagnostic methods for detecting these pathogens.

Main Methods:

• Two pilot cross-sectional studies were conducted on hospitalised paediatric oncology patients with diarrhoea.
• Stool samples were analysed using conventional microbiology, polymerase chain reaction (PCR) for parasites, and immunoassays for *Clostridium difficile* and *Cryptosporidium*.
• Specific pathogens investigated included *Giardia lamblia*, *Entamoeba histolytica*, *Cryptosporidium*, and *Clostridium difficile*.

Main Results:

• In the first study, *Giardia lamblia* was detected in 68.5% of samples, *Entamoeba histolytica* in 13%, *Cryptosporidium* in 5.6%, and non-toxigenic *C. difficile* in 22.4%.
• The second study found *E. histolytica* in 10%, *Cryptosporidium* in 4.3%, *G. lamblia* in 1.4%, and *C. difficile* in 5.1% of samples.
• Various bacteria were also identified in a small proportion of samples in both studies.

Conclusions:

• Parasites appear to be significant aetiologies of diarrhoea in Bangladeshi children with malignancy.
• Molecular diagnostic tools offer high sensitivity for detecting a wide range of stool pathogens.
• Conventional diagnostic methods remain useful for identifying key causative agents of diarrhoea in this population.