<< Chapter < Page Chapter >> Page >

Cutaneous aspergillosis is diagnosed using patient history, culturing, histopathology using a skin biopsy. Treatment involves the use of antifungal medications such as voriconazole (preferred for invasive aspergillosis), itraconazole , and amphotericin B if itraconazole is not effective. For immunosuppressed individuals or burn patients, medication may be used and surgical or immunotherapy treatments may be needed.

  • Identify the sources of infection for primary and secondary cutaneous aspergillosis.

Candidiasis of the skin and nails

Candida albicans and other yeasts in the genus Candida can cause skin infections referred to as cutaneous candidiasis. Candida spp. are sometimes responsible for intertrigo , a general term for a rash that occurs in a skin fold, or other localized rashes on the skin. Candida can also infect the nails, causing them to become yellow and harden ( [link] ).

A) a dark, lumpy rash. B) a broken, yellow nail. C) large, white, fuzzy colonies on a plate.
(a) This red, itchy rash is the result of cutaneous candidiasis, an opportunistic infection of the skin caused by the yeast Candida albicans. (b) Fungal infections of the nail (tinea unguium) can be caused by dermatophytes or Candida spp. The nail becomes yellow, brittle, and prone to breaking. This condition is relatively common among adults. (c) C. albicans growing on Sabouraud dextrose agar. (credit a: modification of work by U.S. Department of Veterans Affairs; credit c: modification of work by Centers for Disease Control and Prevention)

Candidiasis of the skin and nails is diagnosed through clinical observation and through culture, Gram stain, and KOH wet mounts. Susceptibility testing for anti-fungal agents can also be done. Cutaneous candidiasis can be treated with topical or systemic azole antifungal medications. Because candidiasis can become invasive, patients suffering from HIV/AIDS, cancer, or other conditions that compromise the immune system may benefit from preventive treatment. Azoles, such as clotrimazole , econazole , fluconazole , ketoconazole , and miconazole ; nystatin ; terbinafine ; and naftifine may be used for treatment. Long-term treatment with medications such as itraconazole or ketoconazole may be used for chronic infections. Repeat infections often occur, but this risk can be reduced by carefully following treatment recommendations, avoiding excessive moisture, maintaining good health, practicing good hygiene, and having appropriate clothing (including footwear).

Candida also causes infections in other parts of the body besides the skin. These include vaginal yeast infections (see Fungal Infections of the Reproductive System ) and oral thrush (see Microbial Diseases of the Mouth and Oral Cavity ).

  • What are the signs and symptoms of candidiasis of the skin and nails?

Sporotrichosis

Whereas cutaneous mycoses are superficial, subcutaneous mycoses can spread from the skin to deeper tissues. In temperate regions, the most common subcutaneous mycosis is a condition called sporotrichosis , caused by the fungus Sporothrix schenkii and commonly known as rose gardener’s disease or rose thorn disease (recall Case in Point: Every Rose Has Its Thorn ). Sporotrichosis is often contracted after working with soil, plants, or timber, as the fungus can gain entry through a small wound such as a thorn-prick or splinter. Sporotrichosis can generally be avoided by wearing gloves and protective clothing while gardening and promptly cleaning and disinfecting any wounds sustained during outdoor activities.

Sporothrix infections initially present as small ulcers in the skin, but the fungus can spread to the lymphatic system and sometimes beyond. When the infection spreads, nodules appear, become necrotic, and may ulcerate. As more lymph nodes become affected, abscesses and ulceration may develop over a larger area (often on one arm or hand). In severe cases, the infection may spread more widely throughout the body, although this is relatively uncommon.

Sporothrix infection can be diagnosed based upon histologic examination of the affected tissue. Its macroscopic morphology can be observed by culturing the mold on potato dextrose agar, and its microscopic morphology can be observed by staining a slide culture with lactophenol cotton blue. Treatment with itraconazole is generally recommended.

  • Describe the progression of a Sporothrix schenkii infection.

Mycoses of the skin

Cutaneous mycoses are typically opportunistic, only able to cause infection when the skin barrier is breached through a wound. Tineas are the exception, as the dermatophytes responsible for tineas are able to grow on skin, hair, and nails, especially in moist conditions. Most mycoses of the skin can be avoided through good hygiene and proper wound care. Treatment requires antifungal medications. [link] summarizes the characteristics of some common fungal infections of the skin.

Table titled: Mycoses of the Skin. Columns: Disease, Pathogen, Signs and Symptoms, Transmission, Antimicrobial Drugs. Aspergillosis (cutaneous), Aspergillus fumigatus, Aspergillus flavus, Distinctive eschars at site(s) of infection, Entry via wound (primary cutaneous aspergillosis) or via the respiratory system (secondary cutaneous aspergillosis); commonly a hospital-acquired infection, Itraconazole, voriconazole, amphotericin B. Candidiasis (cutaneous), Candida albicans, Intertrigo, localized rash, yellowing of nails, Opportunistic infections in immunocompromised patients, Azoles. Sporotrichosis (rose gardener’s disease), Sporothrix schenkii, Subcutaneous ulcers and abscesses; may spread to a large area, e.g., hand or arm, Entry via thorn prick or other wound, Itraconazole. Tineas, Trichophyton spp., Epidermophyton spp., Microsporum spp., Itchy, ring-like lesions (ringworm) at sites of infection, Contact with dermatophytic fungi, especially in warm, moist environments conducive to fungal growth, Terbinafine, miconazole, clotrimazole, griseofulvin.

Key concepts and summary

  • Mycoses can be cutaneous , subcutaneous , or systemic.
  • Common cutaneous mycoses include tineas caused by dermatophytes of the genera Trichophyton , Epidermophyton , and Microsporum. Tinea corporis is called ringworm . Tineas on other parts of the body have names associated with the affected body part.
  • Aspergillosis is a fungal disease caused by molds of the genus Aspergillus . Primary cutaneous aspergillosis enters through a break in the skin, such as the site of an injury or a surgical wound; it is a common hospital-acquired infection. In secondary cutaneous aspergillosis, the fungus enters via the respiratory system and disseminates systemically, manifesting in lesions on the skin.
  • The most common subcutaneous mycosis is sporotrichosis (rose gardener’s disease), caused by Sporothrix schenkii.
  • Yeasts of the genus Candida can cause opportunistic infections of the skin called candidiasis , producing intertrigo , localized rashes, or yellowing of the nails.

Fill in the blank

The most common subcutaneous mycosis in temperate regions is ________.

sporotrichosis

Got questions? Get instant answers now!

Short answer

What yeasts commonly cause opportunistic infections?

Got questions? Get instant answers now!

Questions & Answers

what is infection prevention
Muhammed Reply
good hygiene
Dhaqan
way of preventing disease causing germs
henry
maintenance of sterilization
Pooja
h
Faustina
describe the components of the epidemiology triangle
Muhammed Reply
Hai
Nantongo
hii
Md
where from you
Md
i am Indian
Md
you
Md
Hello friend
effiong
How are you people doing
effiong
أ‌) Host factor ب) pathogen ج) environment
Widad
Hello
Kofi
Hi
Widad
hey hi
kalai
The epidemiologic triangle is made up of three parts: agent, host and environment
Princess
what are the fluids used in biochemistry Lab used to diagnose diseases
Jb Reply
fadumo qule a gemil3
fadumo Reply
Faadum mahamud disease micro biology
fadumo
makuway diinkaraan suaalo
fadumo
history of microbiology
Balqees Reply
Penicillin is caused by what microorganism
Balqees
Penicillin is caused by what microorganism
Balqees
penicillium notatum
Pooja
M sorry I mean penicillin is caused by what Fungi
Balqees
penicillium fungi
Pooja
mention 5 characteristics of prokaryotic cell and also 5 characteristics of euryotic cell
Grace Reply
PROKARYOTES _ does not have nucleus _does not have membrane bound organels like eukaryotes -does not have endoplasmic reticulum _does not have a mitchochondrion _it have plasmid instead of chromosome EUKARYOTE S _have true nucleus _have all membrane bound organels _have mitochondria have
Pooja
continuation _have endoplasmic reticulum _have chromosomes does not have plasmid
Pooja
antigenisity define
kalai
explanation of spores
nahida Reply
what specific types of biological macromolecules do living things require?
Jonathan Reply
define spores its classification
nahida
define spores its structure and classification
nahida
what is a complement
Alecia Reply
something which completes or combine with something else to make it complete.
Kosi
hello
Kosi
medical microbiology
Kosi
you?
Kosi
hi
Amina
Guys who's doing nursing in here
Mumba
I have a question
Mumba
what's the importance of microbiology in nursing
Mumba
yah
Mumba
wow..nice meeting you
Kosi
thanks
Mumba
for
Mumba
anytime
Mumba
microbiology also important for understanding the communicable or non-communicable disease in our hospitals...which is very important for patients and healthy people.
Kiran
what is a microbial flora
Chetan
normal microbial flora
Chetan
Definition of microbiology?
Mohamed Reply
study of microorganisms is known as microbiology
Pooja
no
Mumba
microbiology is the study of small or minute organisms that cannot be seen with our naked eyes but with the aid of a microscope
Mumba
write and explain the infection chain of 6 common disease infections
Adjowa Reply
diphtheria. dysentery. bubonic plague. pneumonia. tuberculosis. typhoid. typhus. Aug 22, 2017
shamim
good afternoon
Dasaah
OK
Dasaah
Good night
fine
Dasaah
which bacteria can be isolated from abattoirs ( slaughter houses).
Omoja
bacteria that csn be isolated from abattoirs are- Clostridium Bacteroides Desulfobulbus Desulfomicrobium Desulfovibrio
Yashkin
what is a microscope
Louise Reply
Is an instrument used to magnify object which can not be seen with our naked eyes.
Mohamed
are virus host specific?
koguriyem Reply
are viruses effective in small dose?
koguriyem
structure of the bacteria
Eunice Reply
classification of viruses
judy Reply
diffrence
fadumo
a went to Sudy
fadumo

Get the best Microbiology course in your pocket!





Source:  OpenStax, Microbiology. OpenStax CNX. Nov 01, 2016 Download for free at http://cnx.org/content/col12087/1.4
Google Play and the Google Play logo are trademarks of Google Inc.

Notification Switch

Would you like to follow the 'Microbiology' conversation and receive update notifications?

Ask