Infectious Disease Cutaneous Disorders Alison Ruiz PA-C MRSA • Can cause any type of skin infection • 59% of purulent skin infections in adults • 75% of purulent skin abscesses in children Antibiogram http://pulse/clinicalresources/pharmacy/documents/ druguseg/antimicrobial/ns/2013antibiogram.xlsx MRSA presentation Treatment of MRSA • MRSA Resistance • Large abscesses, abscess in immune • Cephalexin compromised pts or ones which are also cellulitic • Dicloxacillin • Require with BOTH I&D AND antibiotics • 48% resistant to Clindamycin • Group A strep is resistant to bactrim and Antibiotics likely effective against MRSA doxycycline • Clindamycin • Increasing resistance to Macrolides and • Fluoroquinolones • Check local susceptibility • Bactrim The latest microbial antibiogram: • Nearly 100% susceptible • Doxycycline • PULSE • 82-85% susceptible • Clinical resources --> Pharmacy --> Drug Use Guidelines --> Antimicrobials (left column, middle of page) -->Antibiogram and MIC distribution • Abscess • Often Staph aureus • MSSA or MRSA • 75% of purulent skin abscesses were caused by MRSA • Fluctuant, erythematous, tender nodules often with surrounding erythema Furuncles and Carbuncles • Single deep nodules involving the hair follicle that are often pus filled • Multiple furuncles that drain through several openings in the skin • Pseudomonas, Candida and other Evaluation of Abscess • Bedside Ultrasound distinguishes abscess from cellulitis What is this? Folliculitis • Infected hair follicle • Causative agents: Pseudomonas and Candida, Bacterial • Hot tub folliculitis • Pseudomonas growth in hot tubs (lesions are usually >3cm) • Distribution • Treatment • Remove offending agent and bid cleansing with mild hand soap and usually clears • Can do topical antibiotics • polymyxin B or bacitracin • Severe or extensive cases • PO antibiotics against Strep, staph such as cephalexin, dicloxacillin, azithromycin What is this? Pilonidal Cyst • Tender, swollen, fluctuant nodule • I&D • Remove any debris, hair for the abscess cavity • Pack with iodoform gauze (remove in 2-3 days) • Surgical consult for possible excision What is this? Bartholin Gland Abscess • When infected cause pain • I&D and placement of the word catheter to allow drainage • Word catheter can be left in for 4 weeks • Sitz baths after 2 days • +/- antibiotics: nonSTD infections, use cephalexin plus metronidazole • Marsupialization prevents recurrence What is this? Cellulitis • Most common B-hemolytic strep, S. aureaus (including MRSA), gram – aerobic bacilli. • Erythema, tender, warm, swollen, no sharp demarcation from uninvolved skin • Symptoms occur gradually over days • Lymphangitis and LAD can occur Cellulitis and Peau d’orange What is this? Erysipelas • Superficial skin infection involving the upper dermis and prominent lymphatic tissue • Caused by b-hemolytic strep • Bullous erysipelas • More severe and ½ of the cases in 2004 were from MRSA Symptoms of Erysipelas • Usually abrupt with fevers, chills & malaise in prodromal phase • In 1-2d, small area of erythema develops & burning sensation • Much more distinctly demarcated from the surrounding normal tissue (unlike cellulitis) Work up • Who needs cultures (wound • Xrays and/or blood) • If concern for osteomyelitis • In toxic pt or necrotizing soft tissue infections • Immunocompromised pt • Pt with many comorbid • IN Cellulitis conditions • Dopplers • Pt recurrent infections • To distinguish from DVT Differential Diagnosis for Cellulitis/Erysipelas • Necrotizing soft tissue • Superficial infection thrombophlebitis • Herpes Zoster • Insect tings • Bursitis • Contact Dermatitis • Osteomyelitis • Gouty Arthritis • Toxic Shock Syndrome • Drug Reaction • DVT • Malignancy Treatment • Antibiotics • Simple cellulitis in healthy pt • PO • Otherwise use IV and likely admission • Elevation • Surgical consult • If bullae, crepitus, pain out of proportion with examination or rapidly progressive erythema Antibiotic Therapy • ORAL • Cephalexin 500mg po q6h • Dicloxacillin 500mg po q6h • Clindamycin 150-450mg q6h • PARENTERAL • Cefazolin 1g IV q8h • Oxacillin 1-2g IV q6h • Nafcillin 1-2g IV q6h Severity ofTreatment Illness Type for of InfectionMRSA CellulitisAntibiotics Mild Skin Abscess after I&D No antibiotics OR Cellulitis Clindamycin 300mg tid for 7-10d OR Bactrim DS bid +/- cephalexin 500mg qid for 7-10d Moderate Stable pt with celluiltis Clindamycin 600- or abscess after I&D 900mg IV q8h OR requiring hospitalization Vancomycin 1gram IV q12 h OR Worsening infection Linezolid 600mg IV despite outpt therapy q12 h Severe NSTI, Sepsis, Pt with Vancomycin 1gm IV significant comorbidities q12h +Meropenem 500-1000mg q8h IV OR Piperacillin/Tazobacta m 4.5g q6h, or imipenem-cilastatin 500mg q6h Treatment for Erysipelas • Most often treated with parenteral antibiotics • Cover for strep (most common organism) • Ceftriaxone 1gram IV qd OR • Cefazolin 1-2grams IV q8h • Will also cover for staph aureus • In the case where it is difficult to determine if the infection is erysipelas vs cellulitis • Admit the patient What is this? Impetigo • Affects children, commonly around the nose and mouth • Direct contact with infected person or fomites • S. aureus or S. pyogenes • Honey yellow crusts is typical finding. • Bullous lesions can occur. • Treatment • Topical saline and aluminum acetate soaks followed by 2% mucpirocin ointment • Systemic involvement • Treat with Cephalexin or macrolide • 20% is MRSA and can be treated with Clindamycin What is this? Necrotizing Infection • Fulminant, extensive soft tissue necrosis • Systemic toxicity • High mortality • Also known as • Fournier gangrene • Necrotizing fasciitis • Necrotizing soft tissue infection • Gas gangrene • Mortality rate 25-35% • Bacteremia is a strong predictor of mortality • Increased risk for death are pt’s <1 yrs old or >60 yrs old Who is at Risk for Developing Necrotizing Fasciitis? • Advanced age • NSAID use • DM • decubitus ulcers • alcoholism • chronic skin infections • peripheral vascular disease • IV drug abuse • heart disease • immune system impairment • renal failure • HIV • cancer Causative Agents • Type I (Polymicrobial) • Type III • 55-75% of all infections • V. vulnificus • Occurs in pts who have • Type II (monomicrobial) insignificant skin break • Gr A strep alone or with and were in seawater S.aureus environment • CA-MRSA (community acquired MRSA) • IV drug users, athletes and institutionalized patient Pathophysiology of Necrotizing Fasciitis Clinical Features of Necrotizing Fasciitis • Pain • Anxiety • Diaphoresis • Pt may present with no pain! • Late finding • Bronze or brownish discoloration with a malodorous serosanguineous discharge and bullae present • Systemic features • low grade fever • tachycardia out of proportion with fever Making the Diagnosis • It is a clinical diagnosis • Plain x-rays • +/-SQ gas • Doesn’t show deep fascial gas • CT is more sensitive (80%) • See fascial thickening and edema, deep tissue collections and gas formation • MRI is most sensitive (90%) • Availability may delay to treatment Treatment • Aggressive IV fluids • Transfusion of pRBCs may be needed • Correct anemia from hemolysis • Early surgical intervention • Operative exploration and debridement • Fasciotomy, debridement and amputation • Mortality increases dramatically if debridement is delayed > 24 hours • Antibiotics • Cover for MRSA and Clostridial • Tetanus Prophylaxis PRN What is this???? Tinea Tinea Capitis Tinea Corporis •Patchy, nonscarring areas of alopecia with •1 or more sharply demarcated scaling patches broken hairs and scale at the periphery •May have central clearing •Oral Griseofulvin •Topical antifungals are treatment of choice •Oral if there is widespread tinea or invovlement of the follicles Tinea Crusis Tinea Pedis •Symmetric erythema with peripheral annular •Scales in the web spaces slightly scaly edge •Spares the dorsum of foot •Groin, thighs and buttocks may be involved •Topical antifungals for 1 week after rash clears •Antifungal creams •Clotrimazole, miconazole, ketoconazole, •Clotrimazole, ketoconazole, econazole econazole Tinea Corporis Differential Diagnosis • Pityriasis rosea • Tinea versicolor • Psoriasis • Erythema migrans • Seborrheic dermaititis • Lupus erythematous • Syphilis • Cutaneous T cell lymphoma • Eczema ?????? Pediculosis • Ages 3-11 years most • Treatment affected. • Permethrin cream 1% or 5% applied to hair and left • Found in scalp, behind the overnight followed by ears and on back of the neutral shampoo neck • Pyrethrin cream is applied for 10 minutes and then • Transmission head to head rinsed out contact • Retreatement is advised in 1- 2 weeks. Identify nits (oval gray • • www.headlice.org white egg capsules) or adult lice • Flouresce with woods lamp Pediculosis Infestation ?????? Scabies • Scabies appear in a tunnel or burrow like rash beneath the skin • Eruption 30 days after exposure • Presents with intense, intractable itching worse at night • Head and neck are typically sparred • Treatment • Permethrin cream 5% (cat B in pregnancy) • Apply from neck down for 12 hours, followed by bathing with soap • AVOID LINDANE IN CHILDREN AND PREGNANT WOMEN What is this? Herpes Simplex • Treatable with antivirals • Important to recognize early to treat early • 2 types: HSV-1 and HSV-2 • HSV-1 is the most common cause of viral encephalitis in the US. • Usually <20yrs or >50yrs • Untreated >70% mortality rate • Neonates with HSV • High frequency of visceral involvement and CNS disease • Encephalitis in infants is most often HSV-2 from maternal genital