e. Moisture. Sweating and oiliness can both cause moisture. Excessive
moisture (especially on the palms of the hands and the soles of the feet and under the
armpits) may occur in normal people as well as in people who have a fever. A person
with cold, clammy skin may have a serious medical condition. Abnormal dryness is
noted in people with aged skin, especially during the winter months in temperate
climates where the humidity may be low. Dryness may also be associated with large
doses of atropine-like drugs.
f. Temperature. With the back of your fingers, feel the skin to assess skin
temperature. Increased skin temperature can be caused by infection or heat stroke.
Decreased skin temperature may occur when there is vascular obstruction, shock, or
hypothermia.
2-6.
SPECIALIZED PROCEDURES
a. Bacterial Smears and Cultures. Identifying the bacteria in skin lesions is
very important in determining the cause of the skin lesion and whether the lesion is
primary or secondary. Two methods can be used to identify bacteria: Gram's stain and
a blood culture. In the Gram's stain method, microorganisms are stained with crystal
violet and further treated with other chemicals. The end result is that these
microorganisms can be identified as gram- positive or gram-negative. Appropriate
treatment can then be determined. Gram's stain is a rapid method of examining a
lesion sample for the number and type of bacteria as well as for the character of the
inflammatory matter coming from the lesion. Often the Gram stain provides the first
clue as to the specific cause of the infection causing the skin lesion(s). If skin lesions
are thought to be part of a generalized infection, blood cultures should be taken. Care
must be taken to obtain the blood culture from an area in which there are not skin
lesions. When gram-stain examination and cultures have been performed, a reliable
diagnosis of the cause of the skin lesion can be made and treatment prescribed.
b. Fungal Smears and Cultures. There is a tendency in dealing with skin
problems where fungus is concerned to minimize the necessity for cultures to confirm
the diagnosis. The general impression is that modern antibiotics and antifungal agents
can take care of the fungus problem. However, many skin diseases look very much
alike so that a clinical diagnosis often needs to be supported by a laboratory diagnosis--
a culture. The location of the fungus will determine the type of clinical specimen to be
collected: infected hairs for a fungus attacking hair and nail scrapings for a fungus
attacking nails. Collecting the appropriate specimen, proper handling and processing,
and correct culturing techniques are skills which are generally acquired through
practice.
MD0575
2-7