Loa loa

Topic Completed: 1 October 2018

Revised: 4 February 2019

Copyright: (c) 2018-2019,, Inc.

PubMed Search: Loa loa[TI] free full text[sb]
Page views in 2018: 45
Page views in 2019 to date: 104
Cite this page: Pernick N. Loa loa. website. Accessed April 18th, 2019.
Definition / general
Diagrams / tables

Images hosted on other servers:

Life cycle

Case reports
Gross description
Gross images

Contributed by Bobbi Pritt, M.D.

5 cm long Loa loa extracted from eye

Microscopic (histologic) description
Microscopic (histologic) images

Contributed by Bobbi Pritt, M.D.

Irregularly spaced cuticular bosses

In comparison, Dirofilaria has longitudinal cuticular ridges

Peripheral smear description
Peripheral smear images

Contributed by Bobbi Pritt, M.D.

Knott concentration made and stained with Carazzi to show larvae measuring (on average) 280 μm in length

D. repens versus L. loa

Positive stains

Live larvae in drop of blood

Differential diagnosis
  • Dirofilaria (Pritt: Creepy Dreadful Wonderful Parasites Blog - Answer to Case 513 [Accessed 31 October 2018]):
    • Found in Africa, Asia, Europe versus Loa loa (West and Central Africa)
    • Adults of both worms have a similar size and gross appearance but Loa loa has irregularly spaced cuticular bosses (bumps on the outer aspect of the cuticle), whereas Dirofilaria has longitudinal ridges
    • Morphology of the microfilariae: Loa loa has sheathed microfilariae and nuclei that go to the tip of the tail but Dirofilaria are rarely seen in human blood, are not sheathed and the nuclei do not go to the tip of the tail
Back to top