Fungal Colonization on Human Body Surfaces
CHAPTER ONE
PREAMBLE
Fungi are a major group of living things, originally considered plants lacking chlorophyll, leaves, true stems, roots and reproducing by spores, but now treated as the separate kingdom fungi.
They occur in all environments on the planet and include important decomposers and parasites. Parasitic fungi infect animals including human, other animals, birds, and insects with consequences varying from mild itching to death, in general, humans have a high level of inmate immunity to fungi and most of the infections they cause are mild and self limiting (Adeleke, 2006).
CHAPTER TWO
LITERATURE REVIEW
Fungi are eukaryotic saprophytes that are ubiquitous in nature. Although hundreds of thousands of fungal species are found in the environment, only about 50 produce disease in human.
Pathogenic fungi are sometimes called plant pathogen. According to WKS Worth (1992), there are approximate a little 1.5 million described species of fungi. A little more than 400 of those species are known to cause disease in animal and far fewer of these species will specifically cause diseases in people. There are relatively few species of fungi that are pathogenic to human that can be fatal.
GirolamoFracastro in (1546), first described the typhus and he suggested that this diseases could be contracted from one person to another through direct contact or individual coming in contact with in animate objects referred to as fomite i.e linen, eating utensils, clothing etc. Cooke (1975).
Most fungi generally are not pathogenic to healthy humans. A number of fungi commonly cause superficial infections involving the feet (tinea pedis), nails (tineaonchomycosis). A very limited number of pathogenic fungi such as coccidiodies, Blastomyces, Histoplama infect non-immune compromised individuals. In contrast, persons with severely impaired immune function e.g cancer patients, uncontrol diabetes, are at significant risk for more severe opportunistic fungal infection. Emmons (1979).
CHAPTER THREE
MATERIALS AND METHODS
MATERIALS USED
The following materials are used which include: tubes, measuring cylinder, microscopic slide, cover slip, Petri dish, inoculating needle, conical flask, Autoclave, incubator, oven, weighing balance, spirit lamp, beaker, aluminum foil, cotton wool, distilled water and swab sticks.
STERILIZATION OF MATERIALS
All glassware’s mentioned above are washed with detergent and later rinsed with distilled water. They are left on test tube rack to dry off. Glassware’s are sterilized using hot air oven at 175oC for 30 minutes in order to kill spore of any contaminates that might have stickled to them. The surface of inoculating needle is sterilized with 95% ethanol and later flamed before and after each use.
CHAPTER FOUR
RESULTS AND DISCUSSION
Tables I and II show the positive and sterile results of the swabs culture at weekly intervals postburn.
Table III shows the bacteriological isolates from the burn wounds on human body surface at weekly intervals postburn. The predominant organism was S. aureus which formed 28.4% of all isolates at the end of the first week after admission. However, by the end of the third week, P. aeruginosa had become more predominant (26.9%), while S. aureus formed only 12.2% of all isolates.
CHAPTER FIVE
CONCLUSION
Human skin microflora are important because it plays a strong role in regulating the feeding behaviour and the maintenance of good health. The presence of human skin microflora essential for immunity as these residence microbes defend their territory against diseases causing microbes.
Colonization of the burn wound on human body surface with fungi is not a surprising phenomenon in view of the changes in microbial flora induced by systemic and topical chemotherapy. The origin of the fungi in these patients does not appear to be the gastrointestinal tract as suggested in other studies of diseases complicated by fungemia (Colombo &Guimarães 2003). An epidemiological study demonstrated recovery of Candida from the wounds of 8 to 10% of severely burned patients studied and the absence of fungi in the stool or nasofharynx of these patients (Bruck et al. 1972). Colonization of fungi was found more commonly after third and fourth week postburn.
Species identification revealed that postburn patients harbored various species of Candida. These fungi species are the most common fungal organisms in burn wounds on human body surface (Bruck et al. 1972, Vindenes&Bjerknes 1995)and in this study no other fungi were isolated. The most predominant species obtained was C. tropicalis (10.3%), followed by C. parapsilosis (4.2%). This high incidence of C. tropicalis observed in our study is specially alarming. As it is now well known that unlike C. albicans, which can be found as a commensal, C. tropicalis when present, is not a commensal and is almost always associated with the development of deep fungal infections.
- albicans has always been considered as the most frequent pathogenic species causing nosocomial fungal infections in burn patients, with mortalility rates due to deep-seated infections raging from 38 to 50% (Macedo et al. 2003). However, recently other species of Candida,as C. tropicalis,has emerged to be equally important in immunocompromised patients (Mathews et al. 2001, Leung et al. 2002, Gupta et al. 2004).
The colonization of the wounds on human body surface with Candidaspecies does not validate the start of antifungal therapy in burned patients. However, if the appearance of the wound on human body surface is suggestive of invasive fungal infection, or if the patient has received intravenous antibiotics for bacterial infections (specially older patients with burn larger than 40% total body surface area), or the patient is in a critical phase suggestive of a generalized breakdown on his/her host defense mechanisms, systemic antifungal therapy should be considered.
The high percentage of multi drug resistant isolates is probably due to empirical use of broad-spectrum antibiotics. However, in the instances of imminent clinical burn wound sepsis, the success of treatment greatly depends on prompt administration of empirical i/v antimicrobial therapy.
RECOMMENDATION
Burns provide a suitable site for bacterial multiplication and infection, mainly because of the larger area involved and longer duration of patient stay in the hospital. To ensure early and appropriate therapy in burn patients, a frequent evaluation of the wound on human body surface is necessary. Therefore, a continuous surveillance of microorganisms and a regular update of their antibiotic resistance pattern is essencial to maintain good infection control programmes in the burn unit, thus improving the overall infection-related morbidity and mortality.
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