Presentation on theme: "Fungal Infections of the skin Superficial and cutaneous infections"— Presentation transcript:
1Fungal Infections of the skin Superficial and cutaneous infections
2Skin fungal infections Clinical Skin fungal infections are generally divided intoSuperficialTinea versicolor, Piedra (Trichosporosis), and Tinea nigraCutaneousDermatophytosis, Candidiasis of skin, mucosa, nails and othersSubcutaneousMycetoma, Sporotrichosis, Chromoblastomycosis, and others
3Superficial MycosesDefined as infections in which a pathogen is restricted to the Stratum corneum, with little or no tissue reactionThese affect the uppermost dead layers of skin or hair shaftThey are painless and usually do not provoke the immune systemThey include1- Tinea versicolor2- Tinea nigra3- Piedra
4Tinea VersicolorTinea versicolor is a long-term (chronic) fungal infection of the skinThe fungus interferes with the normal pigmentation of the skinresulting in small, discolored patchesThe most common sitesThe back, underarms, upper arms, chest, and neckTinea versicolor occurs most frequently in teens and young adultsSun exposure may make tinea versicolor more apparentTinea versicolor often recurs, especially in warm, humid weather
5Clinical presentation: Tinea versicolor is a type of infection of the keratinized epithelial cells in the stratum corneum.Hypo- or hyperpignented macules on chest or back.The infection causes patches of discolored skin that may be:Colored white, pink, tan or dark brownSlow-growing, scaly and mildly itchyMore noticeable after sun exposure
6CausesThe fungus that causes Tinea versicolor can be found on healthy skin (normal flora of skin).It only starts causing problems when the fungus overgrowsA number of factors may trigger this growth, including:Hot, humid weatherExcessive sweatingOily skinHormonal changesWeakened immune system
7Malassezia furfur, and Malassezia globosa It is a YeastLipophilicNormal flora of skinDiagnosisSkin scrapingPotassium hydroxide (20% KOH)Positive for short hyphae and yeast cellsSpaghetti and meatballsCultureMalassezia furfurOil should be added to the media
8Pityriasis versicolor commonly causes hypopigmentation in people with dark skin tones
9Superficial Mycoses Tinea nigra: Superficial fungal infectionCauses dark brown to black painlesspatches (macule) on the palms of the hands and thesoles of the feet.This infection is caused by the fungus formerly classified as Exophiala werneckiiMore recently classified as Hortaea werneckii
10Diagnosis Skin scrapings Culture on SDA & Mycobiotic In 10% or 20% KOH will show brown septate hyphaeThe KOH lyses the nonfungal debrisCulture on SDA & Mycobioticgrowth of dematiaceous fungusproduce melanin in their cell wallsAgar plate with the dominant fungi in the salterns, the black yeast Hortaea werneckiiMicrograph of the fungus Hortaea werneckii
11Superficial Mycoses - Piedra Asymptomatic infection of the hair shaft, causing nodules on the hair shaftOn scalp hair, and other body hair.Black piedra (Exothrix infection)Piedraia hortaeDark pigmented nodulesHard and firmly attached to hair shaftWhite piedra( Endothrix infection)Trichosporon beigeliiLightly pigmented, white to brown nodulesSoft, loosely attached
13Laboratory diagnosis 1. Clinical Material 2. Direct Microscopy Epilated hairs with white soft nodules present on the shaft2. Direct MicroscopyHairs should be examined using 10% KOH3. CultureSabouraud's dextrose agar (SDA)White piedraHair with black Piedra
14Treatment of Superficial infections 2% salicylic acid3% sulfur ointmentsWhitfield's ointmentKetoconazolePiedraCutting or shaving the hairOr apply 2% salicylic acidOr 3% sulfur ointmentNizoral shampoo (contains Ketoconazole)Antifungal agentsTopical
15DermatophytosisFungal infections of the Keratinized tissues of the body (mainly: Stratum corneum, Skin epidermis, and dermis could be involved).Scalp, glabrous skin, and nails caused by a closely related group of fungi known as dermatophytesThey are primary pathogens
16Tinea (Ringworm): Classified according to site of inf: ContagiousDirect contact between infected humans or animals (goats, sheep, camel, cows, horses)Transfer form one area of the body to anotherFamilial cross infection occursTinea (Ringworm): Classified according to site of inf:T. capitis scalpT. corporis glabrous (body) skinT. pedis foot (Athlete’s foot)T. cruris groin
17Dermatophytes Etiology A group of related fungi called dermatophytes (filamentous fungi; septate hyphae and conidia):Microsporuminfections on skin and hairEpidermophytoninfections on skin and nailsTrichophytoninfections on skin, hair, and nailsKeratin - utilizing on hosts - humans
18Tinea CapitisRingworm of the scalp (Tinea capitis) is a fungal infection of the scalp hair and epidermis.Highly contagious infectionmost common in toddlers and school-age childrenTreatment for ringworm of the scalp includesmedications taken by mouthmedicated shampooSome cases of ringworm of the scalp result in severe inflammation at the site of infectionthat may cause scarring or permanent hair loss
19Clinical presentation: Papules are solid raised skin lesions with defined borders (less than 1 cm).One or more round patches (Erythematous papules) of scaly skin where the hair has broken off or just above the scalp.Patches that slowly expand or enlarged in circular appearanceScaly, gray or reddened (inflamed) area.Brittle or fragile hair that easily pulls outTender or painful areas on the scalp.
21CausesRingworm of the scalp is caused by one of several varieties of mold-like fungi called dermatophytesMicrosporum canis or Microsporum gypseumEpidermophyton floccosum.Trichophyton mentagrophytes.
22Methods of transmission Ringworm is contagious and can spread in the following ways:Human to humandirect skin-to-skin contact with an infected personGeophilic speciesKeratin - utilizing soil saprophytesObject to human: Anthropophilic speciesclothing, towels, bed linens, combs or brushesAnimal to human : Zoophilic species:dogs and cats, especially kittenscows, goats, pigs and horses
23ComplicationsKerionKerion is the result of the host's response to a fungal ringworm infection of the hair follicles of the scalp with secondary bacterial infection.
24Tests and diagnosis Tests typically include a visual exam History Sometimes, you may take a sample of the hair or skinHistoryClose contacts, duration.Morphology of lesionBroken hairs, black dots, localizedWoods LampBlue greenCulture
25Tinea Capitis - Treatment Must treat hair follicleTopical , but might be not effectiveSystemic agentsGriseofulvin for children – is taken by mouth as a liquid or tabletSide effectsSensitive skinTerbinafineYou may prescribe one of these medications for six weeks or more
26Tinea Corporis - Ringworm (body) Ringworm of the body is one of several forms of ringworm, a fungal infection that develops on the top layer of the skinIt's characterized by an itchy, red circular rash with healthy-looking skin in the middleRingworm gets its name from the characteristic ring that can appearRingworm on the arm
27Clinical presentation: A circular rash on the skin that's red and inflamed around the edge and healthy looking in the middleSlightly raised expanding rings ofred patches, scaly skin on the trunk or faceA round, flat patch of itchy skin
28Causes Microsporum canis or Microsporum gypseum Epidermophyton floccosum.Trichophytonmentagrophytes;(Micro-and Macro-conidia;Lactophenol-cotton blue)
29Risk factors predisposing for dermatophytosis: Living in humid or crowded conditionsHave close contact with an infected person or animalShare clothing, bedding or towels, with fungal infection patientSweat excessivelyParticipate in contact sports, such as wrestling, football or rugbyWear tight or restricted clothingHave a weakened immune systemComplicationsA fungal infection rarely spreads below the surface of the skinPeople with weak immune systems, may find it difficult to get rid of the infection
30Tests and diagnosisYou will determine if patient have ringworm or another skin disorderskin scrapings or samples from the infected area and look at them under a microscopea procedure known as a potassium hydroxide (KOH) testIf a sample shows fungus, treatment may include an antifungal medicationIf the test is negative but you still suspects that patient have ringworm, a sample may be sent to the laboratory for testingthis test is known as a cultureyou may also order a culture if condition doesn't respond to treatment
31Candidiasis (Yeast Infection) Candidiasis is a fungal infection that can affect areas such as the:SkinGenitals, ThroatMouth, Blood.Overgrowth of a type of yeast called Candida,usually Candida albicansDimorphic fungi that isnormally foundin human body.
32Oral Candidiasis (Thrush) A yeast infection of the mouth or throat area is called thrushHealthy adults do not usually get thrush. It is most often seen in:InfantsElderlyPatients getting chemotherapyPeople with AIDS or other conditions that weaken the immune systemIt can also be seen inpeople with diabetesin those who take antibioticsasthma inhalers with steroid medication
34Yeast Infection of the Genitals Vaginal yeast infections are common in women. Common symptoms include:Extreme itching in the genital areaSoreness and redness in the genital areaWhite, clumpy vaginal dischargePainful intercourseBut men can get a yeast infection, too. Symptoms in men include:Red rash on genitalsItching or burning on the tip of the genitalsIt is important to get treated for a genital yeast infection. You may pass the infection back and forth to a sexual partner
35Subcutaneous Fungal Infection A-Sporotrichosis:Caused by Sporothrix schenkii.B-Mycetoma (Madura foot):-Localized skin abscess due to granulomatousinfection of dermis and subcutaneous tissue.-Caused by:1-Pathogenic soil fungi: Madurella mycetomatis.2-Bacteria: Actinomycetoma:Actinomyces species or Nocardia.