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Mould Identification: A Virtual Self Assessment
Current: Unknown C

Unknown C

Mould identification: a virtual self assessment

Case history

An otherwise healthy 25 year old male presented with an ulcerated, erythematous plaque on a tattooed area of the left forearm. This lesion had begun 15 months previously as a papule, which he thought, resulted from a scratch received whilst installing insulation. Slow enlargement had occurred despite several courses of antibiotics and two attempts at excision. Culture from a skin biopsy grew the fungus shown below.

Unknown c clinical presentation — Clinical presentation: skin lesions

Unknown c microscopic morphology — Microscopic morphology of Unknown C showing broad, sparsely septate coenocytic hyphae. No spores were seen.

What is your identification?

Apophysomyces elegans

Apophysomyses variabilis

Saksenaea vasiformis

Saksenaea oblongispora

Information message

OK so it’s a non-sporulating zygomycetous fungi, but which one?

The patient is not responding and the clinician needs a definitive species identification to optimize antifungal treatment.

For non-sporulating zygomycetous fungi, ITS sequencing is required for differentiation of species, and may be necessary to achieve identification in a timely manner (Alvarez et al. 2010, Walther et al. 2012, Halliday et al. 2015).

Here is your ITS gene partial sequence ready to perform a pairwise sequence alignment.

atggctatga ttctagtctt tgctctaaac aaaaactaga accatctctt atcctgtgca atgaatttgt cgcctggggt ttgaaaatag tctttgggcc ctctctttct tgggagcctt tagctgaccc caataggcat tctttattaa accacttttt tgtaactgaa aaaccaaatt tttttcttga tggatcttat cattgagaag tttaaccaaa tgggttgtat atattctagt atatacggct tgtttgaaaa acaactttta gcaatggatc tcttggttct cgcatcgatg aagaacgtag caaactgcga taagtagtgt gaattgcatt tagtgaatca tcgaatcttt gaacgcacct tgcactcact ggtattccgg tgagtacgcc tgtttcagta tcattgaaaa cacacaatca aaacatttct tttggtttga ttggctttgg gtctatcaaa aagtttggct tgtttcttac aagccaagcg gcctgaaata tattgtctgg ctaattgcat cgttgatgat cgctattaga ctttggcttt tttaaatgaa ctggaggttg attaaccagt tttagcttta gtcaaatggt cattgtaaaa aaaatctcga tcttggctag gtgtttatag ccgaaaattt ttttttggct ataaccgaaa ccaatataat cacatttagtt

Now copy the above sequence, go to one of the databases listed below and perform a search.

MYCOBANK Database
To perform a pairwise sequence alignment use the link provided, paste the above sequence into the “align” box, check the disclaimer box, hit the “start alignment" box.

GenBank
To perform a pairwise sequence alignment use the link provided, select nucleotide blast, paste sequence into the “enter query sequence” box, select “Other” in the database section, hit the BLAST button.

Hopefully you will get the right answer.

References:

Alvarez, E., A.M. Stchigel, J. Cano, et al. 2010. Molecular phylogenetic diversity of the emerging mucoralean fungus Apophysomyces: proposal of three new species. Revta Iberoam. Micol. 27: 80-89.
Alvarez, E., D. Garcia-Hermoso, D.A. Sutton, et al. 2010. Molecular phylogeny and proposal of two new species of the emerging pathogenic fungus Saksenaea. J. Clin. Microbiol. 48: 4410-4416.
Halliday, C., S.E. Kidd, T.C. Sorrell and S. C-A. Chen. 2015. Molecular diagnostic methods for invasive fungal disease: the horizon draws nearer? Pathology 47: 257-269.
Walther, G., J. Pawlowska, A. Alastruey-Izquierd et al. 2012. DNA barcoding in Mucorales: an inventory of biodiversity. Persoonia 30: 11-47.

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