The main bacterial pathogen associated with impetigo is Staphylococcus aureus, which are Gram-positive bacteria that are ubiquitously present in the environment (Melles et al., 2004). Other cases of impetigo involve bacterial species, Staphylococcus pyogenes, which is also known as group A beta-hemolytic streptococci (GABHS).
One unique feature of impetigo is that it could occur as either a primary or secondary infection in an individual. Secondary infection is often involved with its occurrence with a pre-existing infection of the skin, as exemplified by eczema and scabies (Lizano et al., 2007). Impetigo can occur as one of two forms, namely bullous and non-bullous.
Majority of the impetigo cases are of the non-bullous form (Koning et al., 2003). The bacteria commonly infect areas of the skin that are frequently exposed to the environment, such as that of the face, as well as the arms and legs. Bullous impetigo generally affects the facial and trunk regions of the body. It is also possible that the buttocks and perineum are infected with bacteria. The blisters associated with bullous impetigo are generally of a diameter of 3 centimeters.
It has been suggested that young children are highly susceptible to this type of skin infection because they frequently come in close contact with people, including that in the home and in the child care centers (Beheshti and Ghotbi, 2007). Other environmental conditions serve as additional risks in acquiring impetigo.
For example, individuals who live or work in crowded conditions are more likely to develop this skin infection due to the close contact with other individuals that may be carrying the bacterial pathogen. Warm temperatures and humidity can also increase the likelihood of skin infections, as these are optimal conditions for bacteria to thrive in. It is also possible to acquire the bacteria through contact sports because of the close interaction with other players and the presence of sweat and heat during these activities. Impetigo may also affect the elderly, especially if their immune system has weakened or their likelihood of wound healing is poor, such as that observed in diabetics.
DIAGNOSIS OF IMPETIGO
Impetigo is generally diagnosed through the presence of symptoms such as shingles, as well as cold sores on different areas of the body. In addition, a patient may also show signs of fungal infections in combination with eczema. In order to precisely determine the type of impetigo in a patient, a differential diagnosis should be conducted.
For non-bullous impetigo, symptoms such as shingles, as well as cold sores, facilitate in making an accurate diagnosis. Other symptoms for non-bullous impetigo include fungi-based skin infections, as well as eczema. In the case of bullous impetigo, the presence of thermal burns, including blisters, determine the precise type of impetigo.
There may be instances when complications do occur, and these are associated with cellulitis, as well as septicemia, which are conditions that reflect the further spreading of the infection to the other parts of the body. It is also possible to observe lymphangitis in a patient with bullous impetigo. Unfortunately, impetigo has also lately been associated with methicillin-resistant Staphylococcus aureus (MRSA), a bacterial plague that has taken center stage in the field of infectious diseases (Noguchi et al., 2006). It has been established that the transmission of the infection is mainly through direct contact with the skin sore.
The main method for diagnosis is through taking swab samples of the skin areas that has been reported by the patient to be infected. The swab samples are analyzed in the laboratory for the presence of Staphylococcus bacteria. Unfortunately, the identification of the bacteria does not automatically resolve whether the skin condition is an actual infection or a colonization event.
The method of tissue sample collection also influences the results of the diagnostic test and thus it is important to exercise caution with regards to the methods of collection and analysis (Yamasaki et al., 2005). It is also important to correlate the results of the diagnostic test and the actual appearance of the skin lesions. Another measure for precise diagnosis and treatment is to have the patient checked again after seven days of treatment, in order to determine if the current medication is indeed taking effect or not. If the skin lesions appear to be the same or minimally healed after seven to fourteen days of treatment, then it is possible that the initial diagnosis is incomplete or incorrect.
PATHOGENESIS OF IMPETIGO
The initial pustules of impetigo appear on the face, with a concentration in the areas surrounding the mouth, as well as the nose, of the patient. It is also possible to observe the first few pustules in areas that have been cut, scratched or bitten, as these areas are prime substrates for the multiplication of the bacterial pathogen (Metts, 2002).
Impetigo is initially observed as a red-colored sore which ruptures within a few days (Hanakawa et al., 2002). The fluid contents are released and a brown-colored crust develops above the area of the pustule. This skin disease is very contagious and the infection is easily spread to other parts of the body by scratching and constant contact with the sore itself. The skin sores are generally not associated with any pain and thus does not bother an individual except for the sight of the reddish sore on his skin.
In addition, an individual with impetigo does not show any signs of fever hence it is less likely that the individual will be alarmed of the presence of a few sores on his skin. However, the skin sores multiply to other areas of the body and generate dark-colored crusts and by this time, the individual often contemplates on seeking medical attention. Unfortunately, by the time the individual is attended to by a physician, he has already come in contact with a number of other individuals and the bacterial pathogen has already spread.
The wounds associated with impetigo generally heal within a few weeks, yet there may be complications linked to this infection that are deemed fatal. One of the serious complications of impetigo is acute renal failure. An individual diagnosed with impetigo can actually return to his daily activities such as schooling or working if he has been on antibiotic treatment for at least 24 hours.
TREATMENT OF IMPETIGO
There are currently a number of treatment options that are available for impetigo. The treatment formats range from oral capsules to skin ointments, where the main component of the medication is an antibiotic (Taylor, 2004). However, it has been recommended that both formats be administered to a patient with impetigo, in order to fully control the further spread of the infection to the rest of the body, as well as to other individuals (Fleming et al., 2007). Despite the availability of different treatment options, there is currently a debate on the most effective method of treating this particular skin infection (George and Rubin, 2003).
Biomedical scientists are still contesting on whether the oral route or the topical route of treatment is more efficient, yet evidence-based practice indicates that topical ointments are as effective as oral treatment of impetigo (Koning et al., 2002). Other treatment options have emerged, such as those topical ointments that are supplemented with corticosteroids to hasten the reaction, as well as antiseptic formulations that could be used as washing liquids. There are also novel ointments that have included scents such as tea and ginger (MacDonald, 2004).
It is also important to determine the extent of the skin infection, in order to appropriate administer an effective antibiotic treatment. In cases wherein impetigo is still limiting, it has been suggested that muciprocin can be administered as an effectual therapy for impetigo (Koning and van der Wouden, 2004). However, patients with extensive conditions of impetigo should be treated with antibiotics through the oral route (Brown and Wise, 2003). Oral medications such as penicillin, as well as cephalosporins, are thus considered as the appropriate drugs for treatment.
Clinical investigations have suggested that the most reliable method of determining if a treatment for impetigo has resulted in a clinical cure is to determine whether the patient is relieved of the symptoms after one week of therapeutic intervention (Brown and Wise, 2002). Earlier perceptions were that impetigo was a self-limiting infection and thus the natural progression of the infection would definitely cease after an appropriate period of time. However, it is still important to treat a patient with impetigo since this skin disease is highly contagious and thus the necessary precautions should be implemented to prevent its further transmission.
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