Could aflatoxin B1 production by Aspergillus flavus affect the severity of keratitis: an experience in two tertiary health care centers, Egypt

  • Ghada Ibrahim Ibrahim BarakatEmail author
  • Yasmin Nabiel Kamal
  • Amira Mohammed Sultan
Original Article


To investigate the expression of AFB1 gene in isolates obtained from corneal scrapping samples from keratitis patients and to correlate the quantity of AFB1 to the severity of keratitis. An observational study was undertaken in Medical Microbiology and Immunology department, Mansoura University, Egypt, over corneal scrapping samples that were cultured aiming to isolate fungal causes of infective keratitis followed by AFB1 gene detection in Aspergillus flavus isolates by nested PCR then quantitation of the toxin by TLC. Out of 843 corneal scrapping samples collected from patients with infective keratitis, positive fungal growth was identified in 277 cases (32.9%). A. flavus was the commonest fungal agent isolated in 93 cases (33.6%). The AFB1 toxin–encoding gene was detected in 63.4% of A. flavus isolates. There was a positive correlation between the quantity of produced AFB1 toxin and the degree of severity of keratitis (P value < 0.0001*). Aspergillus flavus was the most common cause of fungal keratitis, with the AFB1 toxin–encoding gene detected in more than half of the isolates. A significant correlation between the degree of severity of keratitis and the quantity of produced AFB1 toxin was detected. Therefore, exploring presence or absence of AFB1 toxin is important for the clinicians in their diagnostic assessment and selection of proper treatment choices.


A. flavus Aflatoxin B1 Fungal keratitis Nested PCR Thin-line chromatography 


A. flavus

Aspergillus flavus


Aflatoxin B1

Nested PCR

Nested polymerase chain reaction


Thin-line chromatography


Compliance with ethical standards

Conflict of interest

The authors declare that they have no conflict of interest.

Ethical approval

The study protocol acquired an approval from our institutional review board (MS.18.11.360).

Informed consent

An informative consent was received from each study participant.


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Faculty of MedicineMansoura UniversityMansouraEgypt

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