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Jpn. J. Med. Mycol.
Vol. 32, Suppl, 1-9, 1991
ISSN 0916•\4804
Medical Mycology Today
D.W.R. MACKENZIE
Mycological Reference Laboratory,
Colindale, London NW9 5HT, England
President
International Society for Human and Animal Mycology
Although medical mycology is recognized by its practitioners as an independent area
of professional commitment, its roots can be traced to a broad range of medical and
biological disciplines. It incorporates elements from such diverse fields as dermatology,
genetics, pathology and histopathology, infectious disease, veterinary medicine, mycology, immunology, microbiology, epidemiology, and more recently, cellular and molecular
biology. It follows that the term "medical mycologist" is an imprecise one, and does
not adequately indicate origins and spheres of interest of those who work in the field.
Medical mycology is perhaps best viewed as a mosaic rather than an amalgam, the
cement which binds its component parts together being mycology itself. It is an interest
in the fungi, their products and their activities which constitutes the single unifying ele-
ment that links medical mycologists and their endeavours throughout the world.
In this presentation, I wish to concentrate on medical mycology as it is today. The
history of its development is of equal relevance to an understanding of the subject is
the history of its development, but I propose to explore this topic more fully in my
Presidential Address at the 11th ISHAM Congress in Montreal next year.
Medical Mycology : International Aspects
The spectrum of medical mycology today
varies considerably from country to country. To some extent, the International Society for
Human and Animal Mycology (ISHAM) reflects the interest taken in medically important fungi
and their associated diseases throughout the world. The reflected image is an imperfect
one, for in some countries, financial regula-tions, administrative complications, low sala-
ries, and difficulties of communication, inclu-ding those related to language, may conspire
to make membership impracticable. Neverthe-less, a study of the ISHAM membership shows
several interesting and revealing features. The Society has 840 members from 68 coun-
tries (Table 1). The United States, with 231 members has the biggest membership (27.5%) .
Japan has 80 members (9.5%), followed by the United Kingdom with 55, and the combined
Germanies with 52. These four countries ac-
count for almost 50% of the Society's total membership.
Predictably, distribution of the membership is uneven : thus, 41 (80%) of the 68 countries have fewer than five members, and 27 (40%)
fewer than three. Tropical countries account for 29 (43%) of the total number of countries,
but only 15% of the total membership. Not
surprisingly , membership from countries where English is spoken as a first language is high,
40% of the total being in this category.
When distribution figures are viewed in terms
2
of the regions defined by the World Health Organization, startling inequities become evi-
dent (Table 2). Thus only nine members are located in Africa
(1%), 16 from the East Mediterranean (2%), and 25 from SE Asia (3%). The West Pacific
(which includes Japan) accounts for 15% of the membership, with Europe and the Americas
40% each. Only 65 of 126 WHO States (51.6
%) have ISHAM members. There is only one member from China and
three from the Soviet Union. There are none
from Kenya, Jamaica, the Phillipines, Burma, Papua New Guinea, and many other parts of
the globe where mycoses are known to con-
stitute an important public health problem. ISHAM therefore represents only a propor-
tion of the world's mycological community. Regional interests are sometimes served by national and other international societies (Ta-
ble 3). The Japanese Society for Medical Mycology
Table 1. ISHAM membership by country
Table 1. ISHAM membership by country (continued)
Jpn. J. Med. Mycol. Vol. 32 (Supplement 2), 1991 3
is one of 19 organizations formally affiliated with ISHAM. With more than 900 members,
it is larger than ISHAM itself, and arguably the most vigorous of all national mycopatho-
logical societies. It is to such Societies that ISHAM looks for regional leadership and for
productive interaction in the international forum.
Other international organizations providing some support for medical mycology include
the International Union of Microbiological
Societies (IUMS), and the International Myco-logical Association (IMA). The IUMS has an active Mycology Division, which promotes in-
terest in mycopathology at IUMS Congress,
and by organizing occasional training Courses. Programmes for both the IUMS Congress in
Osaka, and the IMA Congress in Germany in-cluded sessions on medical mycology. The IMA
Congresses are the biggest international meet-ings devoted to mycology. The 1990 Congress
in Regensburg attracted more than 1600 my-
cologists. The largest Congresses devoted to medical mycology, however, are those orga-
nized by ISHAM. The number of participants expected to attend the Society's 11th Congress
in Montreal may exceed 1,000.
Medical mycology : the world literature
The world's scientific literature provides a
direct expression and measure of current in-terest in medical mycology. Papers may be
published in journals specializing in medical mycology, or in a large number and range of
other medical and biological periodicals. Mono-
graphs, reviews manuals and textbooks are more abundant now than ever before.
An analysis of more than 3,000 abstracts pub-
lished in the Review of Medical and Veterinary Mycology during the past year (Table 4), shows
that almost 24% of papers selected for inclu-sion were concerned with mycotoxins and my-
cotoxicoses. An additional 31 % dealt with candidosis and antifungals.
Table 2. ISHAM membership in WHO regions
Table 3. National societies affiliated to ISHAM
4
Perhaps surprisingly, numbers of papers on
histoplasmosis (64) and coccidioidomycosis
(32) constituted only 3% of the total, appre-ciably fewer than those dealing with crypto-
coccosis (3.5%). These figures are related to current emphasis on studies of Candida, can-
didosis, and antifungal chemotherapy, although dermatomycoses are still attracting consider-
able attention. Sources of papers on dermatomycoses, asper-
gillosis and candidosis which appeared in the Review of Medical and Veterinary Mycology
are indicated in Table 5, for the Regions defined by the World Health Organization.
Numbers are broadly consistent with the geo-
graphical distribution of mycologists revealed by ISHAM membership.
A survey of papers published during 1989 in the Japanese Journal for Medical Mycology
shows that the range of interests is a wide
one, without any single theme predominating. The topics closely resemble those appearing in the Bulletin of the Societe francais de My-
cologie medical (Table 6).
Medical mycology : the status quo
Much present-day attention focuses on di-
agnosis and treatment of mycoses, and on features and qualities of the fungal cell of-
ten in the context of antigenic or biochemical
Table 4. Review of Medical and Veterinary Mycology (1989)
Abstract topics (n=3051)
Table 5. Review of Medical and Veterinary Mycology (1989) Regional origin of publications
Jpn. J. Med. Mycol. Vol. 32 (Supplement 2 ), 1991 5
studies which may be applied to serological or immunopathological aspects of infection.
A more recent interest is the study of geno-typic or phenotypic characteristics which can
be used for epidemiological studies. Molecular
biology is providing new tools, approaches and
perspectives, but their full impact on medical mycology has yet to be felt.
For those whose primary responsibilities are clinical, interest in the fungi is often indirect
rather than direct, being concerned not with fungal biology but with diagnosis and manage-
ment of mycoses as infectious diseases.
Such individuals may be described as elec-tive rather than career mycologists. As a rule,
these correspond to part-time and full-time commitments respectively. These are not in-
tended to be pejorative terms, and it may be noted that most members of ISHAM and its
affiliated societies are in this category. Their contributions to diagnosis, therapy,
immunology, pathology, and epidemiology, are crucial to the viability and advancement of
medical mycology, but progress in fundamental
knowledge of the biology of the fungal cell
depends more heavily on research conducted by
the full-time professionally trained scientist.
Science has made great strides over the past
two decades, and it can be anticipated that
fundamental advances will in the future be
made by scientists from disciplines other than
mycology. Medical mycologists today, com-
pared with their predecessors earlier in the century, can now be more readily seen as
applied rather than basic scientists, increasin-
gly dependent on methodologies borrowed or adapted from newer disciplines for their studies
on mycoses and their causal agents.
Both categories of mycologists, career and
elective, can work independently and produc-
tively in areas where mutual dependency is
not required, but continuity and sustained
progress in clinical mycology is best achieved when their skills are combined and expressed
synergistically.
In my view, free communication and pro-
ductive interaction between clinical and non-
clinical mycologists are of paramount impor-
Table 6. National societies of Japan and France publication
themes (Nos. of papers)
6
tance today for the future well-being, vigour,
productivity, and perhaps even the continued existence of medical mycology as an independ-
ent subject. There has been a tendency over the past few
years for medical mycology to become separa-ted into its component parts, and for inde-
pendent units to assume responsibility for what are often highly specialized areas of in-
volvement. This is particularly evident in clinical my-
cology where new laboratory diagnostic pro-
cedures or chemotherapeutic agents are being assessed in a hospital environment. This is
undoubtedly the most appropriate location for such activities, but fragmentation of medical mycology, or sometimes its incorporation
into other medical disciplines as a matter of organizational convenience or economic neces-
sity, could have far-reaching and partially harmful effects on the future of the subject.
These effects may not be immediately apparent, but financial and administrative expediency
and altered priorities may contribute to a steep decline of interest in fungal biology and
in the vital role played by the medical mycolo-
gist in maintaining the fabric and integrity of the subject.
Isolation is a fore-runner of decline, and the
importance of such meetings as the present one, together with the positive influence of natio-
nal and international societies in promoting and sustaining interest in the subject cannot
be over-emphasized. The particular quality of individual mycolo-
gy units throughout the world depends on the combination of location, primary field of interest, and the background and special in-
terests of the individual scientists comprising
the group. Comparison of groups in different
parts of the world shows very wide differences in their nature, primary responsibilities and
activities, and in their funding, productivity and influence.
Mycology units originate because specific needs have arisen which are sufficiently com-
pelling to justify their formation. These units
generally have service responsibilities, with or without teaching and research elements. In
most cases they have a recognizable field of
primary interest, such as dermatology, or in-fectious disease. Several explanations may be
offered to suggest why mycological competence
in these units is today less centred on profes-
sional mycologists than in earlier years.
One is that patterns of infectious disease and
priorities have changed, sometimes radically. Another is that laboratories have enhanced
their ability to identify potentially pathogenic
yeasts by means of commercially available kits, and are therefore less dependent on the
professional skills of a trained mycologist. Moreover, future identifications of pathoge-
nic moulds may be facilitated by commercial
exoantigen systems and perhaps even revolu-
tionized by procedures based on DNA technolo-
gy, although the ultimate value of such aids remains to be determined.
Finally, there has been a substantial shift
of primary interest in the past decade towards
opportunistic mycoses, where to an increasing
extent, diagnostic parameters and manage-
ment strategies are based on clinical rather
than laboratory criteria. In such instances,
the range of laboratory tests employed at
individual medical centres tends to be more
restricted and specialized, relating only to the
particular categories of patients and the spec-trum of anticipated mycoses.
This is an era of change. At one time, new
laboratory diagnostic procedures were deve-
loped primarily by career mycologists, often
working in a hospital environment. Commer-
cial companies produced and retailed kits only
after the efficacy of the test procedure had
been convincingly demonstrated. Examples in-
clude the kits available for identification of
Candida albicans, based on the extensive
pioneer work by Professor Tsuchiya, and his associates, and the latex agglutination test for
detection of Cryptococcus polysaccharides an-
tigen, introduced nearly 30 years ago.
In the past 10 years, however, development
of new technologies and procedures has acceler-
Jpn. J. Med. Mycol. Vol. 32 (Supplement 2), 1991 7
ated, and production of new tests has become
increasingly associated with commercial com-
panies. This is welcome in the sense that their
commitment, resources and production skills
are usually superior to those available in most
service orientated mycology laboratories.
Several new kits are now available which
may prove in time to be of great value as
diagnostic aids. The introduction of new kits
based on the latest technology and on best
available methodologies and reagents, is wel-
come. It is nevertheless true that tests may be
marketed with incomplete evaluation of their
true value or limitation in a clinical setting.
In view of the undesirability of basing pa-
tient management on the results of inconsis-
tent or inadequately evaluated tests, to say
nothing of their often substantial costs, some
form of independent evaluation for each new
test in the setting for which it was developed,
is essential. I believe career and elective my-
cologists are equally indispensible in this con-
text, as are carefully planned cooperative trials,
where merits and demerits are determined,
and results published. It is reassuring to find
that two new serodiagnostic kits commercially
available for candidosis and aspergillosis in
Europe are being refined and improved on the
basis of user experience.
Attention is being paid in several parts of
the world to clinical trials with new antifun-
gal drugs. The point has already been made
that the mycological element is sometimes of
minor importance, evaluations being based
primarily on clinical rather than mycological
parameters. As and when effective prophylaxis
and accurate clinical diagnostic parameters
become available, the overall need for mycolo-
gical diagnostic services will diminish. This
may not happen within the present decade,
but I think it inevitable that some of the self-
contained specialized units working on clinical
mycology which we see today will in time
change their areas of commitment, and that
some mycological units will disappear. I also
think it predictable that responsibility for la-
boratory diagnostic work in some countries
will be increasingly entrusted to competent
bench technicians, probably working part-time, but who are skilled with the use of basic test
procedures, including commercial kits. I believe the reduced dependency on career
mycologists will continue, and that this loss of mycological capability will inevitably lead
to a loss of cohesion of the subject, and a lack of continuity in existing medical mycology
units. This is a challenging time for professional
mycologists. If their future role is confined to identification of rare or unfamiliar isolates,
they may find themselves increasingly dis-tanced from the clinical interface, and its key
areas, diagnosis and management. It is my belief that if medical mycology is
to continue into the next millenium as a dis-cipline in its own right, careful and construc-
tive thought must be given to its future role. Mycological competence will be required as
long as the spectrum of opportunistic fungal
pathogens continues to expand. I am not advocating opposition to change.
On the contrary, innovations are an essential
component of progress. It is nevertheless important to ensure as far as possible that
changes do not happen without awareness and approval of their occurrence and consequences.
Medical mycology is more vigorous in some countries than in others. This may have little
or no relationship to numbers of members of national or international societies. For ex-
ample, Thailand or Latin America as a whole may not appear prominently in membership
lists of international professional societies,
but mycoses are important public health pro-blems there as elsewhere, and substantial num-
bers of mycologists are currently employed in diagnostic, investigative and educational capacities in these parts of the world.
Medical mycology appears to be more stable in some countries than in others. Where it has
been based on traditional (botanical) origins,
the decline has been most marked. Fungal tax-onomy today has few devotees and minimal
career opportunities. A knowledge of classific-
8
ation, however, is still the basis of reliable
identification, and although the number of
competent taxonomists needed today is small-
er than it was 30 years ago, their continued
existence and activities are of critical impor-
tance, if mycology is to retain its identity as
an independent discipline.
In countries such as Japan and France, where
medical mycology is strong, and its platform
secure, support is received from disciplines
such as parasitology, biochemistry, phamaco-
logy, and industrial microbiology. Their innate
strengths provide both sustenance and vigour
to studies on the medical aspects of mycology.
Education
Mycology is not a primary profession, in the sense that it is not available as a degree
course. Basic and applied mycology is taught at a variety of levels and to varying degrees
at both undergraduate and postdoctoral levels,
and on many medical and science courses. It achieves greatest prominence as a component
of university courses in Plant Pathology and Industrial Mycology. Courses in mycological taxonomy are almost non-existent now, and
training in this area is largely confined to major Culture Collections.
In 1986, ISHAM compiled the first edition
of an International Register, listing courses where training in mycology can be obtained
throughout the world. Copies were lodged with the WHO in Geneva. This first edition was very incomplete: it was limited to 93 entries
from 33 countries, and contained only two contributions from Japan. I would urge that
this International Register should be revised, through the active cooperation of all 20 natio-
nal and international organizations currently
or prospectively affiliated to ISHAM. As the number of professional mycological
medical mycologists diminishes, the number and perhaps quality of courses on orthodox mycology is also becoming increasingly reduc-
ed. If medical mycology is to maintain its
identity, consideration must be given to the continued provision of educational opportu-
nities. It is in this area that I believe the
greatest need and potential exists for fruitful cooperation between the international commu-nity.
It is not my mission to call for the conser-vation of classical mycology, to put back the
clock, and to resume the widespread teaching of taxonomic mycology in undergraduate
courses. If I have a recognizable mission, it is to seek recognition for the continuing need
for Education. This is where the future of mycology lies, and this is where all existing
mycologists, elective and career alike, can help, by appreciating the reality of current needs
and responding to them. I am certain that ISHAM has enormous potential as a source of
educators, and that it could play a decisive role in future training of basic, clinical, mo-
lecular, veterinary and other forms of myco-logy.
Recognition of the continuing need for Edu-cation is crucial to the survival of medical
mycology as a coherent discipline. For those seeking special training and knowledge, courses
and workshops, books, manuals and journals, will continue to be the mainstays of educa-
tional programmes. However, it will also be necessary to explain its continuing need clearly
and convincingly to those whose support is necessary for its survival. This includes senior
governmental health officials, university ad-ministrators and educators, and appropriate
international agencies. There is little doubt that medical mycology could benefit greatly
by making its presence known and its impor-tance better understood, to those concerned
with delineation of health priorities and appor-tionment of funds.
Conclusions
In Japan, as elsewhere, changes in the status
and involvement of medical mycology are
taking place, and should be appreciated for
what they are. The future of mycology may
depend to a large part on the care and plan-
ning which is done today. It may not be true
to say that Medical Mycology as we under-
Jpn. J. Med. Mycol. Vol. 32 (Supplement 2 ), 1991 9
stand it is in a crisis, but individual elements assuredly are. Career medical mycologists,
for example, may even be regarded as an en- dangered species, and their role certainly needs
to be redefined. Mycology is undergoing a challenging and
exciting metamorphosis. Much that is innova-tive is originating in the fields of molecular
biology and immunology. New methodologies are becoming available, and new concepts are
emerging. We can now reinvestigate and reap-
praise old problems with newly forged tools. It is an exciting time: one of discovery and change. Above all, it is a time to appreciate
the need for collaborative thought and action, and the benefits which this would bring.
The climate has never been more suitable for communication and cooperation than it is
today. The benefits of joint scientific inves-
tigation are clear from the most cursory of examinations of the scientific literature. All research laboratories have their own primary
fields of interest, which can occupy their at-tention full-time. There are nevertheless oppor-
tunities recognizable today, as never before, for the imaginative creation of approaches
involving the joint skills of different centres,
through the formation of specific research
projects or working groups.
National Societies might find it to their advantage to consider regional manpower and
training needs, production of technical manuals detailing methodologies for serological tests,
antifungal assays, DNA studies and coordi-nated clinical trials.
Consideration might also be given to work-shops or even the formation of Working
Groups on specific topics, such as Cell Wall Biology, Candida or Aspergillus biology, Cryp-
tococcosis, or Opportunistic fungi. Productive
collaboration is both stimulating and rewar-ding. Cross-discipline interaction is needed more now than ever before. The list of potentially
productive topics is endless. The future is in your hands. Medical My-
cology is in a state of flux. You are creators
of its identity, the custodians of its present and the architects of its future. I do not fear
for the subject here as I do elsewhere. Meet-ings such as the joint Japan-China Conference
in Xian during 1987, and the successful Chiba. University Symposia are a tribute to the ima-
gination and enthusiasm of those involved in their organization, and precedents for other national Societies to emulate. May the future
of your Society and its associated activities
continue with unbated vigour and success.
Recommended