giardiasis

Introduction

Giardia lamblia is a flagellated protozoan parasite infecting the small intestine and biliary tree

-it is endemic around the world 

-risk factors: drinking contaminated water, hypochlorhydria, immunocompromise, unprotected sex, exposure to infected day care centers, camping sites, swimming areas

-After ingestion, cysts excyst in the small intestine and release flagellated trophozoites in the proximal small intestine. Both cysts and trophozoites are excreted in feces.  

-Chlorination does not destroy cysts; they can be eradicated from water by either boiling or filtration 

-In the United States and Europe, Giardiasis is the most common intestinal protozoan pathogen

Symptoms & Signs 

-the manifestations of infection range from asymptomatic carriage (most common) to chronic diarrhea and malabsorption 

Acute giardiasis: nausea, vomiting, abdominal pain, bloating, belching, flatus, diarrhea; The stool is greasy in appearance, foul-smelling, and floats. It is usually devoid of blood or mucus. 

Chronic giardiasis: can be episodic or continual; diarrhea, increased flatulence, sulfurous belching, weight loss, malabsorption,vitamin deficiencies,  growth retardation, dehydration; stools are foul smelling, greasy or frothy, without blood, pus or mucus. 

Diagnosis

-It can be diagnosed by detection of parasite antigens in the feces, by identification of cysts or trophozoites in the feces or by nucleic acid amplification tests 

-Cysts are oval and contain four nuclei; Trophozoites are pear-shaped and contain 

two nuclei and four pairs (8) of flagella; they have ventral sucking disks 

Treatment 

Effective agents: Metronidazole, tinidazole, quinacrine, furazolidone, nitazoxanide and paromomycin 

-Unlike metronidazole, tinidazole, furazolidone is safe in pregnancy 

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Google photo

You are commenting using your Google account. Log Out /  Change )

Twitter picture

You are commenting using your Twitter account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s

This site uses Akismet to reduce spam. Learn how your comment data is processed.