Impetigo & Ecthyma (1 of 10) 1 Patient (usually a child) presents w/ skin lesions that are suggestive of impetigo or ecthyma 2 DIAGNOSIS No ALTERNATIVE Is impetigo or ecthyma DIAGNOSIS confi rmed? Yes 3 THERAPY Topical DECISION Oral antibiotic Does clinical condition warrant antibiotic use of a topical or oral antibiotic? A Pharmacological therapy A Pharmacological therapy (Topical) 1st-line: 1st-line: • Flucloxacillin • Fusidic Acid 2nd-line: 2nd-line: Any one of the following oral agents: • Bacitracin • Aminopenicillin/beta-lactamase inhibitor • Mupirocin • Cephalosporin (1st generation) • Retapamulin • Cephalosporin (2nd generation) B Patient education • Macrolide Alternative • Cephalosporin (3rd generation) B Patient education • FOLLOW-UP REVIEW DIAGNOSIS & THERAPY Yes Improvement after No 7-10 days of treatment? • ASSESS COMPLIANCE W/ THERAPY & HYGIENE MEASURES • DO CULTURE & SENSITIVITY NO FURTHER TREATMENT NECESSARY - Swab beneath lifted edge of • crusted lesion Longer treatment may be needed for ecthyma • - Nasal passage swab for TREAT BASED ON suspected carriers of CULTURE & Staphylococcus aureus SENSITIVITY RESULTS © • NASALMIMS MUPIROCIN FOR S aureus CARRIERS Not all products are available or approved for above use in all countries. Specifi c prescribing information may be found in the latest MIMS. B168 © MIMS 2019 Impetigo & Ecthyma (2 of 10) 1 IMPETIGO & ECTHYMA Impetigo • A very contagious, superfi cial, bacterial skin infection that easily spreads among people in close contact • Most cases occur in children & resolve spontaneously w/o scarring in approximately 14 days • Complication: Risk of glomerulonephritis esp in children aged 2-6 yr Ecthyma • Deeply ulcerated form of impetigo that extends to the dermis - “Punched-out” ulcers w/ yellow crust & elevated violaceous margins • Most cases occur in children & elderly • May be a de novo infection or a superinfection 2 DIAGNOSIS • Diagnosis is usually based on clinical presentation Clinical Presentation Nonbullous Impetigo • Most common form of impetigo; also known as crusted impetigo or impetigo contagiosa • Most commonly occurs in children 2-5 yr of age • Initially presents w/ macules or papules that quickly become small vesicles - Vesicles quickly pustulate & rupture leaving an erosion or clusters of erosion - Purulent discharge dries & forms honey-colored crusts • Usually asymptomatic though local adenopathy is common; pruritus or pain may occur occasionally • Lesions are typically found on exposed areas of the skin on the face (esp around the nose & mouth) & extremities • Predisposing factors: Poor hygiene; warm climate; crowding; preceding skin breaks in the aff ected area from insect bites, wounds, viral infections (chicken pox, herpes simplex), scabies or burns; prior skin disease eg eczema, atopic dermatitis • Etiology: S aureus & group A beta-hemolytic streptococci (GABS) • Carrier state: 4% of adults may be asymptomatic carrier Bullous Impetigo • Newborns & younger children are commonly aff ected • Lesions (0.5-3 cm in diameter) typically develop on intact skin & begin as vesicles that turn into fl accid bullae that contain yellow serous fl uid IMPETIGO & ECTHYMA - Bullae rupture easily & a moist red-surfaced erosion appears surrounded by a thin rim of scale, which then forms a thin varnish-like light brown crust • Generally, there is no surrounding erythema but may have regional lymphadenopathy, pain or systemic symptoms • Lesions are often multiple, rapidly spread, & typically found on the face, buttocks, perineum & extremities, the trunk more frequently aff ected; in neonates, around the diaper area • Etiology: Always caused by coagulase-positive S aureus - A localized form of staphylococcal scalded skin syndrome Ecthyma • Typically occurs in children 6 mth-18 yr, in the elderly, immunocompromised (eg neutropenia, HIV), or patients w/ diabetes mellitus (DM) • Lesions initially appear as pustules & vesicles that become ulcerated - Ulceration is frequently covered by adherent crusts • Associated w/ pain & lymphadenopathy; heals w/ scarring • Lesions are usually found on the legs • Predisposing factors: Insect bites, scabies, pediculosis, poor hygiene & malnutrition, heat & high humidity • Etiology: Group A beta-hemolytic streptococci (Streptococcus pyogenes); S aureus is typically cultured from the lesions but is usually a secondary pathogen Lab Tests • Tests are not necessary in most cases because diagnosis is made on clinical grounds • Gram stain &/or culture may be used to confi rm the diagnosis when the clinical presentation is unclear or if the patient fails fi rst treatment - Gram stain smears of vesicles show Gram-positive cocci - Culture & sensitivity test reveals the causative agents & the appropriate therapy esp when resistant organisms are suspected© MIMS • Take blood cultures when patient appears ill & when infection is severe, recurrent, suspected to be an outbreak, or suspected to be caused by Methicillin-resistant S aureus (MRSA) B169 © MIMS 2019 Impetigo & Ecthyma (3 of 10) 2 DIAGNOSIS (CONT’D) Alternative Diagnosis • Infectious: Candidiasis, cellulitis, dermatophytosis, ecthyma, erysipelas , HSV, scabies, varicella • Non-infectious: Atopic eczema, burns & scalds, contact dermatitis, drug reaction, insect bites, Stevens-Johnson syndrome, toxic epidermal necrolysis • Rare: Bullous pemphigoid, pemphigus foliaceus 3 THERAPY DECISION • Duration of treatment is tailored according to clinical improvement - If unresponsive or deteriorating, it is reasonable to extend beyond 7 days while waiting for the C&S results Topical Antibiotic erapy • May be appropriate in localized nonbullous impetigo located away from the mouth (child may lick topical antibiotics if applied near the mouth) • Used to treat single lesions or small areas of involvement (localized impetigo) Oral Antibiotic erapy • Preferred treatment in patients w/ systemic symptoms, widespread nonbullous impetigo, lesions near the mouth, bullous impetigo, ecthyma patients in cases where there is evidence of deep involvement (eg cellulitis, furunculosis, etc), recurrent infection or in immunocompromised, those unable to tolerate topical antibiotics • Parenteral antibiotics may be needed for widespread ecthyma Others • Hygiene measures alone are not recommended even for localized lesions since untreated impetigo is highly communicable & may become generalized • Topical antiseptics (eg Hydrogen peroxide cream) are not recommended due to limited evidence regarding its eff ectiveness & its tendency to cause skin reactions Referral • A referral to a pediatrician or dermatologist may be considered when: - Diagnosis is unclear - Infection is extensive, severe, or unresponsive to maximal therapy in primary care setting - Recurrence is frequent IMPETIGO & ECTHYMA A PHARMACOLOGICAL THERAPY Topical Antibiotics • Must be applied after crust removal to enhance penetration - Soften crusts w/ a wet cloth compress - Removal of scabs during the process of healing is not recommended • Use should be limited to 2 wk due to risk of contact sensitization & antibiotic resistance development Fusidic Acid • 1st-line topical antibiotic • Eff ects: Has been proven to be as clinically eff ective as Mupirocin - Active against staphylococci (including Methicillin-resistant strains) & streptococci Other Topical Antibiotics Bacitracin • Used for many years as topical therapy for localized impetigo • Eff ects: Has been shown to be eff ective against S aureus and group A streptococci Mupirocin • Eff ects: Has been proven to be as eff ective as Fusidic acid & several oral antibiotics (eg Ampicillin, Dicloxacillin, Erythromycin & Cefalexin) for treatment of impetigo & produces fewer side eff ects than oral agents - Considered as 2nd-line of treatment after Fusidic acid, as it is active against staphylococci (including Methicillin-resistant strains) & streptococci • Carriers© of S aureus in their nares are treatedMIMS w/ mupirocin ointment applied nasally Not all products are available or approved for above use in all countries. Specifi c prescribing information may be found in the latest MIMS. B170 © MIMS 2019 Impetigo & Ecthyma (4 of 10) A PHARMACOLOGICAL THERAPY (CONT’D) Retapamulin • New agent for treating impetigo w/ a short treatment duration of only 5 days • Considered as a 2nd line treatment because of its cost • Suitable alternative to Fusidic acid • Eff ects: Active against S aureus & streptococci - In vitro data show activity against Methicillin-resistant staphylococci Oral Antibiotics • Choice of agent will depend on suspected organism, local resistance patterns, cost & product availability Antistaphylococcal Penicillins • Dicloxacillin & Flucloxacillin - For infections caused by penicillinase-producing staphylococci - May be used to initiate therapy when staphylococcal infection is suspected - Very eff ective but less tolerated compared to Cefalexin - Does not cover MRSA • Amoxicillin + Clavulanate - Indicated for Impetigo and other skin and soft tissue infection caused by Staphylococcus aureus (MSSA) Cephalosporins (1st Generation) • Excellent activity against Methicillin-susceptible S aureus (MSSA) & S pyogenes & is generally well-tolerated • Do not cover MRSA Cephalosporins (2nd Generation) • Cefaclor, Cefprozil & Cefuroxime are among the choices Cephalosporins (3rd Generation) • Variable in their activity against Gram-positive organisms esp MSSA & no inherent advantage to the broader Gram-negative coverage - Broad spectrum of activity tends to exert an increased selective pressure for emergence of antibiotic resistance