Table 3.

Extra-intestinal and long-term consequences of giardiasis

Post-infectious consequences	Speculated mechanisms involved	References
Ocular pathologies	Speculated involvement of toxic metabolites produced by the parasite	[47-49]
Arthritis	Bacterial antigens in synovial fluids possibly due to increased intestinal permeability	[50-52]
Allergies	Alteration in antigen uptakeDysfunction of the intestinal barrier	[54-57]
Hypokalemic myopathy	Loss of potassium related to diarrhea, impaired nutrient and electrolyte absorption	[59-62]
Failure to thrive	Inadequate food intake, Reduced nutrients absorption, excessive utilisation of energy, Steatorrhea, maldigestion, malabsorption	[38,39,63-65,69,71,118]
Stunting	Nutritional status, sanitary, socio-economic conditions, loss of intestinal surface area, maldigestion, malabsorption	[37,63,64,67,77,121]
Impaired cognitive functions	Chronic malnutrition and stunting following G. duodenalis infectionNutrient malabsorption and micronutrient deficiencies	[40,41,63,64,68,76-78]
Chronic fatigue syndrome	Altered natural killer-cell levelsLower ratio CD4:CD8	[15,82-87,89]
Post-infectious irritable bowel syndrome	Microscopic duodenal inflammationInteraction host - gastrointestinal microbiotaIncreased T-cells and Mast-cells	[14,84,93,100-105]
Cancer	No cause-to-effect established	[113-116]