Uporaba mikroskopskih i molekularnih metoda u dijagnostici dermatofitoza u zamorčića

master's thesis

• Title (english): The use of microscopic and molecular methods in the diagnosis of dermatophytosis in guinea pigs
• Author: Mislav Unger
• Mentor: Suzana Hađina (mentor)
• Committee member: Matko Perharić (predsjednik povjerenstva)
• Committee member: Zrinka Štritof (član povjerenstva)
• Committee member: Suzana Hađina (član povjerenstva)
• Committee member: Vilim Starešina (član povjerenstva)
• Granter: University of Zagreb; Faculty of Veterinary Medicine; Zagreb
• Defense date and country: 2023-05, Croatia
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Veterinary Medicine; Veterinary Public Health and Food Safety

Abstract

Dermatofiti su keratinolitičke gljivice koje mogu prouzročiti kožne promjene u životinja i ljudi.
Zamorčići su česti asimptomatski nositelji dermatofita, što je važno imajući u vidu njihovu sve
veću popularnost kao kućnih ljubimaca. Rad mikoloških dijagnostičkih laboratorija koristi
klasične metode laboratorijske identifikacije koje uključuju izravnu mikroskopsku pretragu
dlake, izdvajanje dermatofita na hranjivoj podlozi te njihovu identifikaciju na osnovu
makroskopskih i mikroskopskih obilježja kolonija. Uporaba molekularnih metoda pokazala je
da je neke vrste dermatofita teško razlikovati međusobno samo na osnovu morfologije, ali i
moguće zamijeniti s nekim vrstama saprofitskih plijesni. Cilj ovog istraživanja bio je utvrditi
prisutnost dermatofita na koži i dlaci zamorčića koristeći izravno mikroskopiranje dlake,
kulturelnu pretragu te identifikaciju vrsta dermatofita na osnovu makroskopskog izgleda
kolonija i mikroskopskih obilježja gljivičnih elemenata, lančanom reakcijom polimerazom
(engl. polymerase chain reaction, PCR) i sekvenciranjem. Od sveukupno 24 uzoraka dlačnog
pokrivača podrijetlom od zamorčića kulturelnom pretragom, lančanom reakcijom
polimerazom te sekvenciranjem iz njih četiri izdvojena su i identificirana tri dermatofita vrste
Trichophyton benhamiae i jedan vrste Nannizzia gypsea. Izravnom mikroskopskom pretragom
nije utvrđena invazija dlaka artrosporama dermatofita. Kulturelna pretraga je omogućila
preciznu identifikaciju dermatofita, ali nije bila dostatna za preciznu identifikaciju u slučaju tri
narasle kulture plijesni sličnih dermatofitima koje su identificirane PCR metodom i
sekvenciranjem kao vrste Chrysosporium lobatum, Chrysosporium minutisporosum i
Aphanoascus fulvescens. Prevalencija emergentnog patogenog dermatofita Trichophyton
benhamiae na dlačnom pokrivaču zamorčića ukazuje na potrebu pojačane kontrole zdravlja
zamorčića bez kliničkih znakova dermatofitoze, a u svrhu sprječavanja širenja ove zoonoze.

Abstract (english)

Dermatophytes are keratinophilic fungi that can cause skin lesions in animals and humans.
Guinea pigs are common asymptomatic carriers of dermatophytes, which is important
considering their increasing popularity as pets. Mycological diagnostic laboratories use
classical methods of laboratory identification, including direct microscopic examination of
hairs, isolation of dermatophytes on culture media, and their identification based on
macroscopic and microscopic characteristics of colonies. The use of molecular methods has
shown that some dermatophyte species are difficult to distinguish from each other based on
morphology alone and can also be confused with some saprophytic mold species. The aim of
this study was to determine the presence of dermatophytes on skin and hair of guinea pigs by
direct microscopic examination of hair, culture testing, identification of dermatophyte species
based on macroscopic appearance of colonies and microscopic characteristics of fungal
elements, polymerase chain reaction (PCR) and sequencing. From a total of 24 guinea pig hair
samples, four were isolated by culture test, polymerase chain reaction and sequencing, and
identified as dermatophytes: three of them as Trichophyton benhamiae and one species of
Nannizzia gypsea. Direct microscopic examination did not reveal invasion of the hairs by
dermatophyte arthrospores. Cultural examination allowed accurate identification of
dermatophytes but was not sufficient for accurate identification in the case of three cultures of
molds resembling dermatophytes. These were identified by PCR and sequenced as species of
Chrysosporium lobatum, Chrysosporium minutisporosum and Aphanoascus fulvescens. The
prevalence of the emerging pathogenic dermatophyte Trichophyton benhamiae on guinea pig
hair indicates that increased health monitoring of guinea pigs without clinical signs of
dermatophytosis is needed to prevent the spread of this zoonosis.

• Keywords: zamorčići; dermatofiti; kulturelna pretraga; lančana reakcija polimerazom; sekvenciranje; Trichophyton benhamiae; Nannizzia gypsea
• Keywords (english): guinea pigs; dermatophytes; culture test; polymerase chain reaction; sequencing; Trichophyton benhamiae; Nannizzia gypsea
• Language: croatian
• URN:NBN: urn:nbn:hr:178:529475
• Study programme: Title: Veterinary Medicine; Study programme type: university; Study level: integrated undergraduate and graduate; Academic / professional title: doktor/doktorica veterinarske medicine (doktor/doktorica veterinarske medicine)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-06-16 09:33:43