Symptoms of Giardiasis
The most common symptoms of giardiasis include watery, foul-smelling, and possibly greasy diarrhea, abdominal pain, bloating, flatulence, and weight loss. 1
Primary Symptoms
- Diarrhea is typically watery, foul-smelling, and may contain mucus but not blood 1, 2
- Abdominal cramps and pain are frequently reported 1, 3
- Bloating and excessive flatulence are common complaints 1, 4
- Nausea and vomiting may occur in some patients 1, 5
- Weight loss can develop, especially in chronic cases 1, 6
Additional Clinical Manifestations
- Symptoms can range from asymptomatic carriage to severe diarrheal illness 1, 7
- Steatorrhea (fatty, greasy stools) may be present due to malabsorption 3
- Fatigue and general malaise are commonly reported 2
- Some patients develop milk intolerance during infection 5
- Offensive-smelling stools are characteristic 5
Clinical Course
- Giardiasis can present as either acute or chronic infection 6
- Acute symptoms typically begin 1-2 weeks after exposure 1
- Symptoms may persist for weeks to months if untreated 7
- Chronic infection can lead to significant malabsorption and failure to thrive, especially in children 2, 7
- Some patients develop post-infectious irritable bowel syndrome-like symptoms even after successful treatment 1
Special Considerations
- Giardiasis should be suspected in patients with persistent diarrhea (>11 days) 1
- Recent travel to endemic areas significantly increases risk of infection 1
- The infection may mimic other gastrointestinal conditions such as irritable bowel syndrome or inflammatory bowel disease 1
- Giardiasis is a common cause of infectious diarrhea that is often underrecognized in primary care settings 6
Diagnostic Pitfalls
- Symptoms can be intermittent as cyst shedding is not continuous 1
- Multiple stool samples may be needed for diagnosis due to intermittent shedding 1
- Giardiasis should be considered even in patients without travel history who present with persistent diarrhea 1
- The infection may be confused with other causes of chronic diarrhea, including celiac disease or small intestinal bacterial overgrowth 2
Understanding these characteristic symptoms helps in early recognition of giardiasis, allowing for prompt diagnosis and treatment, which can prevent complications such as chronic diarrhea, malabsorption, and weight loss.