SKIN INFECTIONS. Caroline Charlier-Woerther February 2017

Transcription

1 SKIN INFECTIONS Caroline Charlier-Woerther February 2017

2 LEARNING OBJECTIVES Recognize the main types of infection Know the pathogens associated with them Know how to manage dermo-hypodermitis Know how to manage scabies Recognize and know the principles of treatment for necrotizing cellulitis

3 Impetigo Ecthyma Folliculitis Furuncle/ Carbuncle Cellulitis Necrotizing cellulitis Superficial candida albicans skin infections Dermatophyte infections Scabies Leprosis

4 THE SKIN Folliculitis Impetigo Ecthyma, Furuncle Dermo-hypodermitis Necrotizing cellulitis Necrotizing dermohypodermitis Necrotizing fasciitis

5 SKIN FLORA Resident flora Coagulase negative staphylococci Propionibacterium acnes Corynebacteria Intermittent colonization risk of infection Staphylococcus aureus Streptococcus pyogenes

6 PATHOGENS INVOLVED Bacterias Staphylococcus aureus Streptococcus pyogenes Necrotizing cellulitis = Polymicrobial infections Idem + Anaerobic flora Enterobacteriacae Fungi Candida albicans Dermatophytes

7 PREDISPOZING FACTORS FOR INFECTIONS For all : Minor traumas, preexisting skin lesions, Poor / excessive hygiene conditions (sebum) For cellulitis : Chronic edema (lymphedema, chronic venous insufficiency with venous stasis) Minor traumas including onychomycosis/ ulcer Obesity For necrotizing cellulitis : Diabetes and immunosuppression

8 IMPETIGO Superficial skin infection Epidermis Staphylococcus aureus++ > Streptococcus pyogenes

9 IMPETIGO Children > adults Highly transmittable School Family Non immunizing Face++ (nares) Diagnosis is clinical (Bacteriological examination of the pus)

10 IMPETIGO Non bullous Vesiculous/ bullous lesion Rupture to leave a honeycolored crust Local adenomegaly possible No fever Bullous Staphylococcus aureus Exfoliatin Flaccid bullae

11 IMPETIGO Complications Ecthyma Cellulitis Glomerulonephritis Extension by autoinoculation

12 IMPETIGO Treatment Hygiene : soap/ wash Antiseptic therapy (not evaluated) Temporary school exclusion In France 3 days or until coverage of all sores Antibiotics Mild Severe Crust <2% body surface, < 6 lesions Slow extension local antibiotics mupirocine or fucidic acid: 1appl x 2-3/d for 5-10d Bullous / ecthyma >2% body surface > 10 lesions, Fast dissemination oral antibiotics Targeting Streptococci / Staphylococci Cloxacillin : 2x 500 mg x 2/d Pristinamycine : 1 g x 3/d Amox-clav 1g x 3/d

13 Neglected impetigo deeper lesions with thickly crusted lesions Oral antibiotic therapy Against Staphylococcus aureus/ Streptococcus pyogenes Ex: oxacillin/ amoxicillin/ clavulanic acid ECHTYMA

14 FOLLICULITIS Superficial infection of the hair follicles follicular-based papules and pustules

15 FOLLICULITIS Stye Basis of the eyelashes Inflamed eyelid Sycosis barbae Barber s itch

16 FOLLICULITIS Treatment Hygiene : soap/ wash Local antiseptic therapy Oral antibiotic therapy in severe extensive lesions Against Staphylococcus aureus Ex: oxacillin/ amoxicillin/ clavulanic acid

17 Deeper infections of the hair follicles FURUNCLE /CARBUNCLE Inflammatory nodules with pustular drainage Carbuncle : pustular lesions coalesce to form larger draining nodules

18 FURUNCLE /CARBUNCLE Nodule Pus Ulceration Scar Fever possible in carbuncles

19 FURUNCLE /CARBUNCLE Complications Carbuncle Cellulitis Severe staphylococcal infection of the face (thrombophlebitis) Bacteremia (< 5%)

20 Avoid manipulation Incision / drainage of large lesions Systemic antibiotic therapy in Facial lesions Immunosuppression background Multiple lesions Complications FURUNCLE TREATMENT Against Staphylococcus aureus Ex: cloxacillin or amoxicillin/clavulanate, both 1g x 3/d 10d

21 Deep skin infection : dermis/ hypodermis Streptococcus pyogenes CELLULITIS Acute inflammation local tenderness, swelling and redness Fever / chills Local adenomegaly 2 typical localizations : Leg / face

22 CELLULITIS Created by The University of Iowa Libraries and used with permission

23 CELLULITIS Search for a skin trauma = site of entry for bugs responsible for the infection +++

24 Complications Necrotizing cellulitis/ fasciitis Adenitis Deep venous thrombosis Bacteremia/ glomerulonephritis Recurrence CELLULITIS

25 CELLULITIS Diagnosis mostly clinical Blood cultures (< 5% positivity) Skin punch biopsy culture Bullae culture

26 CELLULITIS Treatment Antibiotic Active against Streptococcus pyogenes Amoxicillin /penicillin G Oral or IV Treatment of the local trauma : intertrigo Treatment of the local edema Elevation of the affected limb, pain killers

27 NECROTIZING CELLULITIS Infection of the subcutaneous tissues ans fascia Polymicrobial infection Staphylococcus aureus Streptococcus pyogenes Anaerobic flora Enterobacteriacae Risk factors : immunodepression (diabetes, ethylism) Extremely severe infection emergency

28 NECROTIZING CELLULITIS Local signs Extension Enhanced pain Local anesthesia/ dysesthesia Dusky skin bullae, crepitus and necrosis Sepsis septic shock

29 NECROTIZING CELLULITIS Principles of management Emergency Prompt surgical debridement of all necrotic tissues ICU Wide spectrum parenteral antibiotics

30 SUPERFICICAL FUNGAL INFECTIONS Clinical features Diagnosis Basics of management

31 SUPERFICIAL INFECTIONS DUE TO CANDIDA ALBICANS Candida Sp. A budding yeast The main = Candida albicans Skin infections Oral infection Nail infection Vulvovaginitis

32 SUPERFICIAL INFECTIONS DUE TO CANDIDA Risk factors (ID or ATB killing the flora) Diabetes Antibiotic therapy HIV infection Pregnancy (vulvovaginitis) Neoplasia Corticosteroids/ immunosuppressive drugs Older age / infants

33 Intertrigo Large folds : axillae/ groin Reddened itching plaques Pustular lesions at the periphery CANDIDA SKIN INFECTIONS

34 ORAL CANDIDIASIS Tongue : glossitis Lips : cheleitis Oral cavity : stomatitis Thrush : non adherent white plaques En.wkipedia.org

35 ONYXIS Candida perionyxis Tender erythematous edematous nail folds Hand > feet Dermatophyte onyxis Feet > hand Thickened yellow nails

36 VAGINAL CANDIDIASIS Itchy burning erythematous mucosa Creamy discharge not spumous (trichomonas) No bad smell not gardnarella (vaginosis) No fever not pelvic inflammatory disease

37 DERMATOPHYTIC INFECTION Filamentous fungi Various species Human/ animal/ other tropism Skin Nail Hair No mucosal involvement

38 SKIN DERMATOPHYTES Tinea pedis = athlete s foot Pruritic scaling plaques Tinea corporis Pruritic erythematous scaling plaques Children with animals fr.wikipedia.org

39 SKIN DERMATOPHYTES Tinea cruris Pruritic erythematous scaling plaques Tinea capitis Various presentations according to the species involved small/ large plaques En.wkipedia.org

40 CANDIDA/ DERMATOPHYTES Diagnosis Local sample Direct examination and culture Treatment Skin infection Local treatment with topical antifungals Mucosal infection Idem Onyxis 1 nail : local treatment > 1 nail : systemic + local treatment

41 SCABIES Skin disease due to the microscopic human itch mite Sarcoptes scabiei The adult lives in the upper layer of the human skin where it burrows to lay eggs Worldwide distribution Transmitted through direct prolonged skin to skin contact with an infected person household/ sexual contacts/ healthcare Itching skin disease : sensibilization towards mite secretion and feces

42 SCABIES Itching In the folds, flexor wrists, interdigital web spaces Night > day Face, palms and sore not involved except in children or ID patients

43 SCABIES Pimple rash (= papular) Burrows may be visible as thin lines in the skin Possible surinfection

44 SCABIES Regular scabies Immunocompetent No crust Contagious Crusted = Norwegian scabies Immunodepressed Crusted lesions Contagious+++++

45 SCABIES Diagnosis Skin scraping to evidence -the mite -the mite eggs May be falsely negative Treatment For the patient, his household contact and sexual partners 1. Scabicide lotion or cream like (benzyl benzoate) OR 2. Scabicide oral treatment Ivermectin D0 and D15 3. Treatment for Bedding clothing and towels Those used within 72 hours should be cleaned (>60 ) or dryed or sealed for 3 days (mites and eggs do not survive longer outside the human skin)

46 MYCOBACTERIUM LEPRAE Mycobacterium with skin+ neurological tropism + upper respiratory tract mucosa + eye M. tuberculosis Leprosy Transmission by droplets from an infected patient : AIR Not very contagious 200,000 new cases / year worldwide Inde, Madagascar, Brazil Angola, Mozambique, RDC, Central African republic, Tanzania

47 LEPROSY Long incubation 5-10 years Skin lesions Unique or multiple Hypo-pigmented, surrounded by normal skin Macule, papule or nodule

48 LEPROSY Long incubation 5-10 years Nerve lesions Sensory loss Thickened peripherical nerves (cubital++)

49 LEPROSY Long incubation 5-10 years Skin and Nerve lesions Stuffy nose/ bleeding nose Lesions due to sensory loss symptoms/index.html

50 LEPROSY Tuberculoid form ++Cellular immunity Few lesions Paucibacillary form Diagnosis Skin smear/biopsy Performed no a skin lesion or on the ear lobe Acid-fast bacilli + culture or and PCR+ Lepromatous form Weak cellular immunity Numerous lesions Multibacillary form Treatment <= 5 skin lesions Dapsone/d + rifampicin/ month 6 months Treatment If > 5 skin lesions Dapsone/d + rifampicin/month + clofazimine months

51 Sources CDC Wikimedia Commons University of Iowa