Mycoses 2016; 1–7 wileyonlinelibrary.com/journal/myc
|
1 © 2016 Blackwell Verlag GmbH
Received: 22 May 2016
|
Revised: 21 September 2016
|
Accepted: 24 September 2016
DOI: 10.1111/myc.12579
Summary
Mycetoma is a chronic granulomatous, subcutaneous disease endemic in tropical and
subtropical countries. It is currently a health problem in rural areas of Africa, Asia and
South America. Nine cases of mycetoma were analysed in a retrospecive study. All
isolates were ideniied by morphological features. The level of species ideniicaion
was reached by molecular tools. Deiniive ideniicaion of fungi was performed using
sequence analysis of the ITS of the ribosomal DNA region and the ribosomal large-
subunit D1/D2. Ideniicaion of acinomycetes was accomplished by the 16S rRNA
gene sequence. Six unusual clinical isolates were ideniied: Aspergillus ustus,
Cyphellophora oxyspora, Exophiala oligosperma, Madurella pseudomycetomais, Nocardia
farcinica and Nocardia wallacei. The prevalence of mycetoma in Venezuela remains
unknown. This study represents the irst report in the literature of mycetoma caused
by unusual pathogens ideniied by molecular techniques.
KEYWORDS
Molecular ideniicaion, Mycetoma, Unusual pathogens, Venezuela
1
Departamento de Ciencias Básicas, División
de Ciencias de la Salud, Universidad de
Monterrey, San Pedro Garza García,
Nuevo León, Mexico
2
Departamento de Microbiología, Facultad
de Medicina, Universidad Autónoma de
Nuevo León, Monterrey, Nuevo León,
Mexico
Correspondence
Dr Gloria M. González, Departamento
de Microbiología, Facultad de Medicina,
Universidad Autónoma de Nuevo León,
Monterrey, Nuevo León, Mexico.
Email: gmglez@yahoo.com.mx
Funding informaion
Vicerrectoría Académica of the Universidad
de Monterrey
ORIGINAL ARTICLE
Molecular ideniicaion of unusual Mycetoma agents isolated
from paients in Venezuela
Olga C. Rojas
1,2
| Rafael B. R. León-Cachón
1
| Maria Moreno-Treviño
1
|
Gloria M. González
2
1 | INTRODUCTION
Mycetoma is a neglected, granulomatous, chronic, subcutaneous infec-
ion of tropical and subtropical countries. Sudan appears to have the
highest number of cases per capita of any country in the world.
1,2
Most
cases of mycetoma occur in India, Mexico, Sudan and Venezuela,
3–5
al-
though there are reported cases in other countries such as Argenina,
Brazil, Iran and Somalia.
6–10
Sporadic cases have also been reported
in countries with mild weather.
11
In Venezuela few cases of myce-
toma have been reported in the literature. This country is located
on the northern coast of South America, at laitudes deined as the
“mycetoma belt”, between laitudes 15° South and 30° North around
Tropic of Cancer. This region has low humidity and a low annual rain-
fall with well-deined alternaing rainy and dry seasons.
5,12,13
Not all
evidence of mycetoma has been reported in the literature. Mycetoma
is characterised by the formaion of a tumour-like swelling with drain-
ing sinuses that expel grains. The size, consistency and colour of the
grain deine the aeiological agent, which can be bacterial or fungal.
Distribuion is not equal around the world; in Lain America mycetoma
is usually caused by acinomycetes in comparison to Africa, which has
a higher incidence of eumycetoma. It is important to highlight that the
distribuion of the aeiological agents can difer even in the same re-
gions of a country.
3
It is important to difereniate bacterial and fungal
aeiological agents because therapy difers with each form. Based on
colour of the grains, acinomycetes produce sot, white, yellow or red
grains, whereas, eumycetoma produce grains that are black or white,
with the later being less in proporion. Grain colour is an easy method
for making an iniial aeiological classiicaion; however, a 60-year-old
paient from Sudan presented a yellow-grain mycetoma that was ini-
ially treated as an acinomycetoma and ater a lack of response it
was recognised that a new fungal agent, Pleurostomophora ochracea,
was the cause.
14
As both, acinomycetes and fungi, are implicated as
causaive agents, it is important to disinguish them to ensure that
correct treatment is given. Acinomycetoma is treated with anibioics,
and eumycetoma with a combinaion of anifungals and surgery.
4,15
Although mycetoma can be diagnosed clinically, this is not conclusive