Case #421 – June 2016

A 62-year-old female from rural Manitoba Province, Canada presented to a health care provider with abdominal pain, diarrhea, and peripheral eosinophilia. A stool specimen was collected in sodium acetate-acetic acid-formalin (SAF) and a formalin-ethyl acetate (FEA) concentration was performed. Figures A-D show what was observed microscopically on a wet mount; Figures C and D were stained with iodine. What is your diagnosis? Based on what criteria?

Figure A

Figure B

Figure C

Figure D

This was a case of strongyloidiasis caused by Strongyloides stercoralis. Diagnostic morphologic features shown in the images included:

a prominent genital primordium (black arrow, Figures B and C).
a short buccal canal (red arrow, Figure C).
a rhabditoid esophagus (blue arrow, Figure B).

The morphologic features of the larvae shown in the images were consistent with first-stage rhabditiform (L1) larvae which is the stage usually found in stool.

More on: Strongyloidiasis

This case and images were kindly provided by Cadham Provinical Public Health Laboratory, University of Manitoba, Winnipeg, Canada.

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Page last reviewed: August 24, 2016

Content source: Global Health, Division of Parasitic Diseases and Malaria