Giardiasis

Explosive

Step 1: View clinicals

A 35 year old man presents with watery diarrhea and nausea for 4 weeks. During this time, his bowel movements changed from once a day to 4 to 6 times a day with foul smelling, loose, urgent stools associated with a crampy abdominal pain. He had lost 8 kg of weight during the same time period. The symptoms started around 1 week after returning from a holiday to Turkey, where he had gone camping and drunk water from a natural spring. His medical and surgical histories are unremarkable but his family history is significant for a sister with celiac disease.


Step 2: Order all relevant investigations

Stool Microscopy

Fresh stool examination for leucocytes, erythrocytes and trophozoites is negative. Fixed stool examination for enteric parasites is negative. Routine stool examination for enteric parasites is negative.

Stool Culture and Antigen Assay

Positive for Giardia. Negative for routine bacteria, rotavirus/adenovirus antigen and Clostridium difficile antigen. The Cryptosporidium antigen is not detected by a Lateral Flow Test (LFT).

Serology for Gluten Antibodies

EMA (Immunoglobulin A anti-endomysium antibodies): negative AGA (IgA anti-gliadin antibodies): negative tTGA (IgA anti-tissue transglutaminase): negative

Endoscopy & Duodenal Biopsy

No macroscopic features suggestive of celiac disease. Biopsies indicated partial villous atrophy. No crypt hyperplasia or intraepithelial lymphocytes. Heavy colonization with G. lamblia trophozoites noted.


Step 3: Select appropriate management

Metronidazole
Gluten Free Diet
Health Education
Isolation


Score: ★★☆