Fungi are ubiquitous in our environment and uncommon respiratory
pathogens in the immunocompetent host; they usually present with
no or mild symptoms that are self-limiting. In an immunocompromised
host these infections can be associated with significant morbidity
and mortality.Given that most symptomatic fungal infections present
with nonspecific findings, early diagnosis requires a high index
of suspicion, close attention to a patient’s clinical course, and
interpretation of the patient’s findings within the context
of host immune status. They are categorized into two groups—those
that cause endemic mycoses and those classified as opportunistic
pathogens (Table 242-1). Included under endemic
mycosis are two fungi, Sporothrix schenckii and Penicillium
marneffei, that are not always thought of in this category
but that share some similarities with others in this group. Included
as an opportunistic pathogen is Pneumocystis jirovecii, an
organism previously called Pneumocystic carinii and
at one time thought to be protozoa.
Table 242-1. Classification
of Fungal Pathogens |Favorite Table|Download (.pdf)
Table 242-1. Classification
of Fungal Pathogens
|Filamentous hyaline septate fungi|
|Scedosporium species |
|Dematiaceous septate fungi (dark molds)|
|Zygomycetes (aseptate hyphae)|
|Endemic Dimorphic Fungi|
Endemic mycoses are geographically clustered1 as
shown in Table 242-2. In cases of suspected infection,
past history, including travel, is important because the organisms
can remain dormant for many years. Outbreaks and clusters of cases of
histoplasmosis associated with soil-disrupting activity have been
described. Respiratory infections caused by opportunistic fungi
generally do not occupy a geographical or ecological niche but are
clustered in centers that care for the immunocompromised host. There
seems to be an increase in the incidence of these infections, likely
related to an increase in number of immunocompromised patients given
intensive antineoplastic and immunosuppressive therapy, related improved
survival, increased clinical awareness for these infections, and
improved diagnostic ability. The incidence of these infections varies among
centers because of factors such as differences in immunosuppressive
regimens, transplants, and use of antifungal prophylaxis. For example,
the incidence of pulmonary zygomycosis has been reported to be increasing
in association with the increased use of voriconazole prophylaxis.2-5 Whether
this increase is a result of the selective inactivity of voriconazole
against zygomyces and hence the related breakthroughs, improved
patient survival related to its efficacy against other known pathogens
such as Aspergillus species or simply due to increasing
susceptibility of the immunocompromised population is unclear.
Table 242-2. Geographic
Locations of the Endemic Mycoses
Log In to View More
If you don't have a subscription, please view our individual subscription options below to find out how you can gain access to this content.
Want remote access to your institution's subscription?
Sign in to your MyAccess profile while you are actively authenticated on this site via your institution (you will be able to verify this by looking at the top right corner of the screen - if you see your institution's name, you are authenticated). Once logged in to your MyAccess profile, you will be able to access your institution's subscription for 90 days from any location. You must be logged in while authenticated at least once every 90 days to maintain this remote access.
If your institution subscribes to this resource, and you don't have a MyAccess profile, please contact your library's reference desk for information on how to gain access to this resource from off-campus.
AccessPediatrics Full Site: One-Year Subscription
Connect to the full suite of AccessPediatrics content and resources including 20+ textbooks such as Rudolph’s Pediatrics and The Pediatric Practice series, high-quality procedural videos, images, and animations, interactive board review, an integrated pediatric drug database, and more.
Pay Per View: Timed Access to all of AccessPediatrics
24 Hour Subscription $34.95
48 Hour Subscription $54.95
Pop-up div Successfully Displayed
This div only appears when the trigger link is hovered over.
Otherwise it is hidden from view.