Skin Infections for the Primary Care Physician

Transcription

1 Saturday CME Lunch Skin Infections for the Primary Care Physician Richard Usatine, MD Professor of Family Medicine, Dermatology, & Cutaneous Surgery UT Health Sciences Center at San Antonio San Antonio, Texas Educational Objectives By the end of this activity, the participant should be better able to: 1. Discuss the pathophysiology of various skin infections. 2. Determine who is at risk for skin infections and appropriate diagnose various skin infections. 3. Identify current medical treatment options for common skin infections. Speaker Disclosure Dr. Usatine has disclosed that he has no actual or potential conflict of interest in relation to this topic. 13

2 Skin Infections Disclosure Statement: Co President, Usatine Media Medical app development company Richard P. Usatine, MD, FAAFP Professor, Family and Community Medicine Professor, Dermatology and Cutaneous Surgery University of Texas Health, San Antonio Author, 9 medical books including: Dermatologic and Cosmetic Procedures in Office Practice. Elsevier, Inc., Philadelphia The Color Atlas of Family Medicine. 2 nd Edition. McGraw Hill, New York, 2013 The Color Atlas of Pediatrics, McGraw Hill, New York, 2014 Cutaneous Cryosurgery. 4 th Edition. Taylor and Francis, London, 2014 The Color Atlas of Internal Medicine, McGraw Hill, New York, 2015 Objectives By the end of this activity, the participant should be better able to: Discuss the pathophysiology of various skin infections. Determine who is at risk for skin infections and appropriately diagnose various skin infections. Identify current medical treatment options for common skin infections. Pathophysiology of Skin Infections Bacterial Fungal Viral Infestations Bacterial Infections Impetigo Strep or Staph or Both Impetigo Cellulitis Abscess Necrotizing fasciitis Non bullous Bullous 1

3 Ecthyma (Impetigo with Ulcerations) Treatment Strep pyogenes and MSSA Oral cephalexin Topical mupirocin when limited disease MRSA TMP/SX Doxycycline Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America Treatment of Impetigo Bullous and nonbullous impetigo can be treated with oral or topical antimicrobials, Oral therapy is recommended for patients with numerous lesions or in outbreaks affecting several people to help decrease transmission of infection. Treatment for ecthyma should be an oral antimicrobial. Treatment of bullous and nonbullous impetigo should be with either topical mupirocin bid for 5 days (strong, high). Oral therapy for ecthyma or impetigo should be a 7 day regimen. Because S. aureus isolates from impetigo and ecthyma are usually methicillin susceptible, dicloxacillin or cephalexin is recommended. When MRSA is suspected or confirmed, doxycycline, clindamycin, or sulfamethoxazole trimethoprim (SMX TMP) is recommended (strong, moderate). Cellulitis Cellulitis Typical uncomplicated non purulent cellulitis: Give an antibiotic active against streptococci: penicillin, amoxicillin, amoxicillin clavulanate, dicloxacillin, cephalexin, or clindamycin. Elevation of the affected area Therapy for any predisposing conditions, such as tinea pedis, trauma, or stasis dermatitis 2

4 Purulent Cellulitis After Machete Wound Cellulitis from MRSA? MRSA is an unusual cause of typical cellulitis (<4%) Coverage for MRSA may be prudent in cellulitis associated with penetrating trauma (including injection drug use), purulent drainage, or with evidence of MRSA infection elsewhere. If so use oral therapy with doxycycline, clindamycin, or SMX TMP. If coverage for both streptococci and MRSA is desired for oral therapy, options include clindamycin alone or the combination of either SMX TMP or doxycycline with a β lactam (e.g., penicillin, cephalexin, or amoxicillin). Abscess Ring Block Before I and D Best treatment is: SCALPELexin Not cephalexin Antibiotics After the Scalpel? SCALPELexin and SMX/TMP In settings in which MRSA was prevalent, trimethoprimsulfamethoxazole treatment resulted in a higher cure rate among patients with a drained cutaneous abscess than placebo. NEJM

5 Scalpel and TMP/SMX (MRSA Proven) Necrotizing Fasciitis Necrotizing Fasciitis Prompt surgical consultation is recommended for patients with aggressive infections associated with signs of systemic toxicity or suspicion of necrotizing fasciitis or gas gangrene Practice Guidelines for the Diagnosis and Management of Skin and Soft Tissue Infections: 2014 Update by the Infectious Diseases Society of America Fungal Infections Tinea capitis Tinea pedis and manus Tinea corporis Tinea cruris Tinea incognito Tinea versicolor 4

6 Question: The boy in this photo has: 1. An abscess 2. Alopecia areata 3. Kerion 4. Folliculitis decalvans Kerion Severe inflammatory reaction to the dermatophyte Boggy raised nodule with hair loss May need oral steroid to treat No I&D No antibiotics Courtesy of Jeff Meffert, MD Microsporum Canis (Minority of Cases in US) Exothrix fungus on outside of hair shaft Fluorescence with a Woods lamp 5

7 Black dots with Trichophyton tonsurans (Most common cause of T. capitis) T. Capitis Diagnosis 1. Clinical diagnosis look for scale, hair loss, black dots and lymphadenopathy 2. Woods lamp: bright green/blue fluorescence with Microsporum infection 3. KOH/culture Scrape scale and broken hairs Place on microscopic slide with KOH Send to lab in sterile urine cup Tinea Capitis New evidence for Tx Terbinafine is more effective than griseofulvin in children with T. tonsurans infection. Microsporum infections griseofulvin is better than terbinafine. Chen X, et al. Systemic antifungal therapy for tinea capitis in children. Cochrane Database Syst. Rev May 12;(5):CD Terbinafine for T. Tonsurans <20 kg ¼ tab = 62.5 mg daily kg ½ tab = 125 mg daily >40 kg full 250 mg tab daily 250 mg tabs are on the $4 and $5 lists Start with 4 weeks and re assess Griseofulvin for M. Canis Griseofulvin mg/kg/d (not 10) for 6 8 wks Give Griseofulvin with a meal absorbed best with food especially fatty food Tinea Pedis Interdigital Moccasin distribution Vesicular 6

8 Two Feet One Hand Syndrome Tinea Corporis Annular lesions with central clearing Concentric rings high specificity for t. corporis Well demarcated borders Tinea Corporis The most likely diagnosis for this patient is: 1. Tinea corporis 2. Candida infection 3. Intertrigo 4. Inverse psoriasis Tinea Corporis Treatment Topical agents for mild to moderate disease El Gohary M, et al. Topical antifungal treatments for tinea cruris and tinea corporis. Cochrane Database Syst Rev Aug 4;(8):CD Oral agents for more extensive or resistant cases adult dosing: Terbinafine 250 mg/d x 2 4 weeks 7

9 Tinea Cruris Tinea Cruris Inverse Psoriasis (Not Tinea Cruris) Tinea Cruris T. Cruris Treatment Topical antifungal agent for 2 3 weeks or until clear Treat feet with topical antifungal if also infected May need oral antifungal if severe terbinafine 250 mg daily x 2 4 weeks Tinea Incognito Tinea incognito 8

10 Tinea Incognito Tinea Incognito Tinea Versicolor Tinea Versicolor Treatment Topical Antifungals Large areas Selenium sulfide, Zinc pyrithione Small areas Ketoconazole or clotrimazole cream Oral is easy One 400 mg dose of Fluconazole Pityrosporum (Malassezia furfur) Ziti and meatballs 9

11 Cutaneous Viral Infections Molluscum Contagiosum DNA Pox Virus Central Umbilication Molluscum HIV 10

12 Molluscum Child with Atopic Dermatitis Treatment Physical Cryosurgery Curettage Topical Cantharidin Imiquimod KOH This worries parents but inflamed molluscum are often about to resolve KOH Topical for home use published March % KOH can be purchased without Rx and the cost is under $14 Herpes Simplex HSV1 Applied daily for months at home The study concluded: Taking into account the efficacy and tolerability, we would recommend using KOH 10% for MC treatment in children. Side effects: Slight stinging after application Hypopigmentation

13 Genital Herpes HSV2 (Courtesy of Color Atlas of Family Medicine) Eczema Herpeticum Severe herpes with atopic dermatitis Oral Herpes 12

14 HSV Diagnosis HSV by PCR genetic probe for HSV DNA Type specific Rapid Herpes Simplex: Treatment 2015 CDC STD treatment guidelines Scrape the base of a vesicle or ulcer to get cells. Earlier lesions give higher yield so choose vesicles over ulcers when possible Culture no longer preferred Lower sensitivity Foot Kaposi s Sarcoma Human herpesvirus 8 (HHV 8) Varicella Zoster Virus 13

15 Zoster Ophthalmicus Corneal scarring after incomplete treatment Antiviral Therapy for Zoster Acyclovir 800 mg 5x/d x 7 10 d Famciclovir 500 mg tid x 7 10d Valacyclovir 1 g tid x 7 d **Treatment in the first 48 hours is the most effective but still valuable in the first 72 hours (Courtesy of Color Atlas of Family Medicine) Zoster ulcerated: Did not get Correct dose of Valacyclovir Maybe the EMR Populated the HSV Dose? Zoster Vaccine CDC recommends for adults 50 years and older Two doses 2 6 months apart Not live vaccine Two doses of Zoster Vaccine is more than 90% effective at preventing shingles and PHN Common Warts Can be Frustrating to Everyone 8 3 Flat Warts HPV Verruca Plana 14

16 Wart Treatments Evidence for Wart Therapies So many options: Topical Destructive Intralesional Systemic Look at the evidence briefly with help of the new edition of Mark Lebwohl s book 8 6 Warts are frustrating! 8 7 Doc, just cut the finger off already! 8 8 So what do I do? Cryosurgery in the office (But will not tie down any children to do that) Repeat every 3 weeks if pt. desires, one study suggests shorter intervals of 1 2 weeks works faster (not convenient) Topical agents at home often with cryo in office Salicylic acid is OTC and affordable Let them choose and avoid writing a Rx Imiquimod with cryo for condyloma Candida antigen by intralesional injection if top 2 fail Reasonable alternative is intralesional MMR (easier to get) Evidence for Candida Intralesional Candida antigen immunotherapy for the treatment of recalcitrant and multiple warts in children Muñoz Garza FZ, Roé Crespo E, Torres Pradilla M, Aguilera Peiró P, Baltá Cruz S, Hernández Ruiz ME, et al. Pediatr Dermatol 2015; 32: In this retrospective review, 220 children with refractory warts received three intralesional injections of 0.2 ml of Candida albicans antigen, one per visit, at 3 week intervals. Results showed that 156 (70.9%) had a complete response, 37 (16.8%) had a partial response, and 27 (12.2%) had no response. An average of 2.7 injections were required

17 Intralesional Candida Antigen Intralesional Candida Injections Preparations vary so dilution may be needed Dilute with sterile saline or lidocaine Inject 0.1 to 0.3 ml into the largest warts using a 30 gauge needle and up to 1 ml per total treatment. Repeat every 4 weeks, up to three treatments. Usatine, et al. Dermatologic and Cosmetic Procedures in Office Practice After 2 monthly injections of Candida ag Question: The most likely diagnosis for the woman presenting with this condition is: 1. Flat warts 2. Condyloma lata 3. Condyloma acuminata 4. Vulvar intraepithelial neoplasia Human Papilloma Virus HPV Most common STI Condyloma most common HPV types are 6 and 11 16

18 HPV Condyloma Cauliflower appearance 14 yo boy sent for psychotherapy for his persistent itching for over 9 months 17

19 Dermatoscopes Scabies mite Dermoscopic signs of scabies: Triangle on top of circle Delta wing jet plane with contrail Darker front legs and mouth parts create the triangle seen with dermoscopy What is the cause of these pruritic papules on the penis? 1. Bed bugs 2. Pubic lice 3. Scabies 4. Herpes 18

20 Scabies Treatment Permethrin is safe in infants and pregnancy Elimite eliminate the mite 60 gram tube apply from the neck down overnight and repeat in 7 days Quicker onset of action than ivermectin. Higher rates of cure in meta analysis. 1,2 Ivermectin oral is effective and a lot easier to use 0.2 mg/kg once with food (No evidence that a second dose is needed) 3 and 6 mg tablets Treat children over 15 kg only Not for use in pregnancy 1. Currie BJ, McCarthy JS. Permethrin and ivermectin for scabies, N Engl J Med. 2010;362(8): Goldust M, Rezaee E, Hemayat S. Treatment of scabies: Comparison of permethrin 5% versus ivermectin. J Dermatol Jun;39(6): Take Home Try not to take any of these infections home from this conference Identify these early in the office with gloves on Recognize the depth of bacterial skin infections and treat accordingly Not everything that looks fungal is fungal Consider getting a dermatoscope for scabies (and skin cancer diagnosis) Look up antiviral dosing as you need it don t rely on your EMR Try new therapies for warts when the same old ones are not working 110 THANK YOU 19

21 Medication Index Skin Infections for the Primary Care Physician The following medications were discussed in this presentation. The table below lists the generic and trade name(s) of these medications. Generic Name Acyclovir Amoxicillin Cephalexin oral Cimetidine Clindamycin Doxycylcine Famciclovir Fluconazole Griseofulvin Herpes Zoster Vaccine Imiquimod Interferon Invermectin Mupirocin topical Penicillin Permethrin Selenium Sulfide Terbinafine Trimethoprim/Sulfamethoxazole Valcyclovir Zinc Pyrithione Trade Name Sitavig, Zovirax Amocil, Larotid, Moxatag Keflex Tagamet Acanya, Benzaclin,l Cleocin, Clinda Derm, Clindagel, Clindets, Duac, Evoclin, Onexton Acticlate, Doryx, Doxy, Vibramycin, Xyrosa, Zenavod None Diflucan Gris Peg Shingrix, Zostavax Aldara, Zyclara Actimmune, Alferon, Avonex, Betaseron, Extavia, Intron A, Rebif Sklice, Soolantra, Stromectol Bactroban, Centany Bicillin, Permapen, Pfizerpen Elimite, Nix Selsun Lamisil Bactrim, Septra Valtrex Head & Shoulders

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