Potentially pathogenic free-living amoebae in contact lenses of the asymptomatic contact lens wearers.
AbstractBackground: Free-living amoebae (FLA) including Acanthamoeba spp. and Hartmannella spp. are the causative agents of serious corneal infection especially within contact lens wearers. Thus contact lenses and their storage case could be a suitable niche for potentially pathogenic amoebae. The main objective of the present study was to evaluate the contamination of contact lenses to free living amoebae using morphological and sequencing based methods. Methods: Overall, 90 volunteers provided their contact lenses. All volunteers wore soft contact lenses. Both lenses were cultured in the same plate. Forty-eight of the volunteers were medical and dentistry student and 42 were oph-thalmology attendees of hospitals in Tehran, Iran. All of the samples were in-oculated to non-nutrient medium and monitored daily for the outgrowth of the amoebae. PCR and sequencing were performed using various primer pairs. Results: Of the 90 volunteers, 9 (10%) were positive for free-living amoebae outgrowth. Morphological analysis revealed that 3 isolates were belonged to Hartmannella genus according to small round cysts and 6 isolates were belonged to Acanthamoeba genus based on the star shape of endocysts. Sequencing re-vealed that Acanthamoeba belonged to T4, T3 and T5 genotype. Hartmannella were also belonged to vermiformis species. Discussion: The presence of potentially pathogenic free living amoebae includ-ing Acanthamoeba and Hartmannella could be a high risk for people using soft contact lenses. These results revealed that improved clarification and profes-sional recommendations for contact lens wearers is of utmost importance.
Khan NA .Acanthamoeba, biology and patho-genesis, 1st ed. Caister Academic Press. 2009.
Marciano-Cabral F, Cabral G. Acanthamoebaspp. as agents of disease in humans. Clin Microbiol Rev. 2003; 16 (2):273-307.
Rezaeian M, Niyyati M. Pathogenic Free Livin Amebas In Human. 1st ed. Tehran: TUMS Publication; 2010.
Kennedy S, Devine P, Hurley C, Ooi Y-S, Col-lum LMT. Corneal infection associated with Hartmannella vermiformis in contact-lens wearer. Lancet. 1995;346(8975):637-8.
Nuprasert W, Putaporntip C, Pariyakanok L, Jongwutiwes S. Identification of a novel T17 genotype of Acanthamoeba from environmental isolates and T10 genotype causing keratitis in Thailand. J Clin Microbiol. 2010; 48 (12): 4636–40.
Visvesvara GS, Hercules Moura, Schuster FL. Pathogenic and opportunistic free-living amoebae: Acanthamoeba spp., Balamuthiamandril-laris ,Naegleriafowleri and Sappiniadiploidea. Immu-nol Med Microbiol.2007;50 (1): 1–26.
Niyyati M, Lorenzo-Morales J, Rezaie S, Rahi-mi F, Mohebali M, Maghsood AH, Motevalli-haghi A, Martín-NavarroCM, FarniaSh, Val-ladares B, Rezaeian M. Genotyping ofAcan-thamoeba isolates from clinical and environmen-tal specimens in Iran. Exp Parasitol. 2009; 121(3): 242-5.
Maghsood AH, Sissons J, Rezaian M, Nolder D, Warhurst, Khan NA. Acanthamoeba geno-type T4 from the UK and Iran and isolation of the T2 genotype from clinical isolates. J Med Microbiol.2005; 54: 755–759.
Rezaeian M, Farnia Sh, Niyyati M, Rahimi F. Amoebic keratitis in Iran (1997- 2007). Iranian J Parasitol. 2007; 2(3): 1-6.
Pens CJ, Costa Md, Fadanelli C, Caumo K, Rott M. Acanthamoeba spp. and bacterial con-tamination in contact lens storage cases and the relationship to user profile. Prasitol Res. 2008; 103: 1241-45.
Martín-Navarro CM, Lorenzo-Morales J, Cabrera-Serra MG, Rancel F, Coronado-Alva-rez NM, Piñero JE, Valladares B. The potential pathogenicity of chlorhexidine-sensitive Acan-thamoeba strains isolated from contact lens cases from asymptomatic individuals in Tenerife, Ca-nary Islands, Spain. J Med Microbiol.2008; 57 (11), 1399-1404.
Lorenzo-Morales J, Martínez-Carretero E, Ba-tista N, et al. Early diagnosis of amoebic kerati-tis due to a mixed infection with Acanthamoeba and Hartmannella. Parasitol Res. 2007;10-2(1):167-9.
Page FC (1988).A New Key to Freshwater and Soil Gymnamoebae. Freshwater Biological As-sociation, Ambleside, UK.
Lasjerdi Z, Niyyati M, Haghighi A, Shahabi S, Biderouni FT, Taghipour N, Eftekhar M, Nazemalhosseini Mojarad E. Potentially patho-genic free-living amoebae isolated from hospi-tal wards with immunodeficient patients in Tehran, Iran. Parasitol Res. 2011;109(3):575-80.
Schroeder JM, Booton GC, Hay J, Niszl IA, Seal DV, Markus MB, Fuerst PA, Byers TJ. Use of subgenic 18S ribosomal DNA PCR and sequencing for genus and genotype identifica-tion of Acanthamoebae from humans with kerati-tis and from sewage sludge. J Clin Micro-biol.2001; 39 (5): 1903–11.
1Rivera W, Edric DV. 18S ribosomal DNA genotypes of Acanthamoeba species isolated from contact lens cases in the Philippines. Par-asitol Res. 2009; 105 (4), 1119-1124.
Grey BT, Cursons RTM, Sherwan JF, Rose PR. Acanthamoeba, bacterial and fungal contami-nation of contact lens storage cases. Br J Oph-thalmol.1995; 79: 601-5.
Midelfart J, Midelfart A, Bevanger L. Microbial contamination of contact lens cases among medical students. CLAO J. 1996; 22(1):21-4.
Boost M, Cho P, Lai S, Sun WM. Detection of Acanthamoeba in tap water and contact lens cas-es using polymerase chain reaction. Optom Vis Sci. 2008. 85 (7): 526-30.
Khan NA, Jarroll EL, Paget TA. Molecular and physiological differentiation between patho-genic and non-pathogenic Acanthamoeba. Curr Microbiol. 2002; 45 (3): 197-202.