Veterinary Research Forum
Vet Res Forum

First report of ocular histoplasmosis in a horse from Iran: molecular, clinical and pathological findings

Document Type : Clinical Report

Authors

Mehran Ghaemi 1
Nasrolah Ahmadi 1
Hassan Sharifi Yazdi 2
Mohsen Ghane 2
Mohamad Sadegh Golvajooei 1

1 Department of Pathobiology, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

2 Department of Clinical Sciences, School of Veterinary Medicine, Shiraz University, Shiraz, Iran

https://doi.org/10.30466/vrf.2021.539776.3237
Abstract
Histoplasma capsulatum is a dimorphic fungus that is traditionally classified in three varieties: Hc var. capsulatum, Hc var. duboisii, and Hc var. farciminosum (HCF). Cytology, hematology, pathology, polymerase chain reaction (PCR), sequencing, and phylogenetic analyses were applied on samples collected from the blood and the eye of a horse with pustular lesions and ocular discharge. Physical examination and cytopathological tests showed H. capsulatum infection. Additionally, the results of two PCR tests confirmed H. capsulatum infection. The phylogenetic tree of the internal transcribed spacer sequence of Iranian H. capsulatum showed homology with the HCF variety. For the first time, H. capsulatum infection in the eye of a horse from Iran was detected and phylogenetically analyzed. This study revealed that H. capsulatum could establish infection in Iranian animals in addition to people, and indicated the role of soil enriched with bird dropping in the preparation of a favorable environment for H. capsulatum propagation. Further investigations are required to clarify the natural history and risk factors associated with histoplasmosis in Iran.

Keywords

Histoplasma capsulatum
Horse
Phylogenetic analysis
Polymerase chain reaction
Taxonomy
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Veterinary Research Forum
Volume 13, Issue 3
Summer 2022
Pages 455-459

  • Receive Date 26 September 2021
  • Revise Date 26 October 2021
  • Accept Date 20 December 2021

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