Impetigo

dermatological disease caused by bacterial infection (Staphylococcus aureus & Streptococcus pyrogen) contagious disease but it is easy to cure by taking oral antibiotics and topical antibiotic cream

1. By, M.Logeshwary ( PharmD III year) IMPETIGO

2. Impetigo is a superficial skin infection that is seen most commonly in children and is transmitted easily from person to person. Based on clinical presentations: DEINITION:

3. There are two ways an initial infection can occur: primary impetigo - is when the bacteria invades the skin through a cut , insect bite, or other injury, and secondary impetigo - is where the bacteria invades the skin because the skin barrier has been disrupted by another skin infection, such as scabies or eczema.

4. Epidemiology: The bullous form most frequently affects neonates and accounts for approximately 10% of all cases of impetigo Based on data from studies published since 2000 from low and low-middle income countries, we estimate the global population of children suffering from impetigo at any one time to be in excess of 162 million, predominantly in tropical, resource-poor contexts. Impetigo is an under- recognised disease and in conjunction with scabies, comprises a major childhood dermatological condition with potential lifelong consequences if untreated.

5. Occurence On exposed skin mainly on face. most common during hot, humid weather, which facilitates microbial colonization of the skin. Minor trauma, such as scratches or insect bites, then allows entry of organisms into the superficial layers of skin, and infection ensues

6. Caused by S. pyogenes But S. aureus either alone or in combination with S. pyogenes has emerged more recently as the principal cause of impetigo The bullous form is caused by strains of S. aureus capable of producing exfoliative toxins Causes

7. BULLOUS IMPETIGO (BLISTERS) This form is caused by staph bacteria that produce a toxin that causes a break between the top layer (epidermis) and the lower levels of skin forming a blister. (The medical term for blister is bulla.) Blisters can appear in various skin areas, especially the buttocks, though these blisters are fragile and often break and leave red, raw skin with a ragged edge. No prior trauma is needed for these blisters to appear.

8. NON -BULLOUS IMPETIGO This is the common form, caused by both staph and strep bacteria. It appears as small blisters or scabs, which then form yellow or honey-colored crusts. These often start around the nose and on the face, but they also may affect the arms and legs. At times , there may be swollen glands nearby.

9. Pathophysiology : Bullous impetigo is caused by staphylococci producing exfoliative toxin that contains serine proteases acting on desmoglein , a structurally critical peptide bond in a molecule that holds epidermal cells together.   This process allows  Staphylococcus aureus  to spread under the stratum corneum in the space formed by the toxin, causing the epidermis to split just below the stratum granulosum .   Large blisters then form in the epidermis with neutrophil . In bullous impetigo, the bullae rupture quickly, causing superficial erosion and a yellow crust, while in non- bullous impetigo,  Streptococcus  typically produces a thick-walled pustule with an erythematous base. Histology of non- bullous established lesions shows a thick surface crust composed of serum and neutrophils in various stages of breakdown with parakeratotic material

10. Symptoms: Pruritus (severe itching) is common, and scratching of the lesions may further spread infection through excoriation of the skin. Other systemic signs of infection are minimal. Weakness, fever, and diarrhea sometimes are seen with bullous impetigo.

11. Signs: Non bullous impetigo manifests initially as small, fluid filled vesicles. These lesions rapidly develop into pus-filled blisters that rupture readily. Purulent discharge from the lesions dries to form golden-yellow crusts that are characteristic of impetigo. In the bullous form of impetigo, the lesions begin as vesicles and turn into bullae containing clear yellow fluid. Bullae soon rupture, forming thin, light brown crusts. Regional lymph nodes may be enlarged.

12. IS IMPETIGO CONTAGIOUS? Impetigo is contagious, mostly from direct contact with someone who has it. Can be transmitted through: 1. towels, 2. toys, 3. clothing or 4. household items

13. DIAGNOSIS Doctors generally diagnose impetigo by looking at the distinctive sores. Sometimes culture test are done rarely to identify the type of bacteria causing lesions. A complete blood count is often performed because leukocytosis is common.

14. TREATMENT Impetigo is not serious, may go away and dry up on its own, and is easy to treat. Mild cases can be handled by gentle cleansing, removing crusts, and applying the prescription-strength antibiotic ointment mupirocin ( Bactroban ). More severe or widespread cases, especially of bullous impetigo, may require oral antibiotic medication for impetigo. impetigo may resolve spontaneously, antimicrobial treatment is indicated to relieve symptoms, prevent formation of new lesions, and prevent complications, such as cellulitis .

15. Treatment: DRUGS DOSAGE INDICATIONS Penicillinase resistant penicillins ( dicloxacillin ) 12.5 mg/kg orally daily in four divided doses for children increased incidence of infections caused by S. aureus First-generation cephalosporins : Cephalexin 25–50 mg/kg orally daily in two divided doses for children - cefadroxil 30 mg/kg orally daily in two divided doses for children - Penicillin administered as either a single intramuscular dose of benzathine penicillin G 300,000– 600,000 units in children, 1.2 million units in adults infections caused by S. pyogenes

16. TREATMENT clindamycin adults 150–300 mg orally every 6 to 8 hours; children 10–30 mg/kg per day in three to four divided doses The duration of therapy is 7 to 10 days. Penicillin-allergic patients can be treated Topical antibiotics, such as mupirocin and bacitracin - used to treat non- bullous impetigo. Mupirocin ointment applied three times daily for 7 days as effective as erythromycin.

17. With proper treatment, healing of skin lesions generally is rapid and occurs without residual scarring. Removal of crusts by soaking in soap and warm water also may be helpful in providing symptomatic relief

18. EVALUATION OF THERAPEUTIC OUTCOMES Clinical response should be seen within 7 days of initiating antimicrobial therapy for impetigo. Treatment failures could be due to noncompliance or antimicrobial resistance. A follow-up culture of exudates should be collected for culture and sensitivity, with treatment modified accordingly.

19. Case study OB, a 3-year-old boy, is brought to the clinic with a facial rash. According to OB's mother, the rash started 4 days ago as little red bumps below his nose. The rash has spread around his mouth and chin. The rash also has changed in appearance to flat, reddened areas with fluid-filled pustules . On physical examination, the pediatrician finds OB to be a content and alert child in no acute distress. His vital signs are stable and within normal limits. The pediatrician notes that some of the pustules have ruptured, leaving weepy, red lesions and honey-colored crusts. The affected area is not excessively warm or swollen. The pediatrician suspects that OB has impetigo. He explains to the mother that impetigo is a contagious condition that requires treatment with antibiotics. He knows that the most common pathogen causing impetigo is ( ? ), with ( ? ) coinfection . The pediatrician is aware that impetigo was traditionally treated with penicillin , but resistance has limited the usefulness of this antibiotic. Instead he hopes to use an antibiotic that effectively will cover staphylococci and streptococci. As the pediatrician checks the supplies of medications available in the clinic, the mother comments that OB will not take any medications by mouth. She asks whether there are any medications that can be applied to the rash, rather than given by mouth. Are there any topical options available to treat OB's impetigo? Whether it is bullous or non- bullous impetigo?

20. Because many cases of impetigo involve coinfection with streptococci, antibiotic selection must consider covering for both organisms. Antimicrobial agents that will cover for both organisms include dicloxcillin , cephalexin , erythromycin, and amoxicillin/ clavulanate . Since OB will not take oral antibiotics, mupirocin ointment is another option. Mupirocin should be used only for mild cases, however. The pediatrician should advise the mother about the importance of not spreading the infection to the rest of the family (or even to other parts of OB's body). The most important measure of prevention is frequent hand washing. OB also should be reminded not to touch the rash. Non- bullous impetigo.

21. Thank you smarties