History

Fact Explanation
Macular areas of depigmentation of the skin Pityriasis Versicolor is a benign superficial cutaneous fungal infection of the commensal yeast in the genus Malassezia. The macules are lighter, but sometimes darker than the surrounding skin. Sun exposure may make it more apparent. Carboxylic acid is released by the organisms through the oxidation of unsaturated fatty acids of skin surface lipids. It competitively inhibit tyrosinase, the enzyme of pigment production in melanocytes which results in hypopigmented macules. But sometimes hyper pigmented macules will appear as a result of enlarged melanosomes induced by the organism. The upper trunk is commonly affected. [1],[2],[5]
Fine scaling over the lesions Pityriasis Versicolor is a superficial fungal infection localized to the stratum corneum.[1],[2]
Mild pruritis This is not common. But sometimes mild pruritus may occur in the affected areas, when the person's body temperature is elevated by exercise or a warm environment, usually just before starting to sweat. Once sweating begins the itching subsides. [1],[4], [5]
Common among young adults ie. when the sebaceous glands are more active, especially during puberty. This is a lipophilic organism; therefore the high lipid content in sebum is a suitable medium for growth. [2], [4],[5]
Common in children living in a warm humid environment. This is a common disorder in temperate zones and seen more frequently in tropical countries. Warmth and humidity provide a suitable environment on skin surface for the growth of Malassezia yeast. [3],[5]
There may be a history of increased sweating. Increased sweating and sebum secretion encourages the growth of the causative organism. [2]
There may be a history of immunosuppression. Pityriasis Versicolor is common among children with AIDS, Cushings syndrome, patients on long term steroids and in children with other immuno deficiencies. When considering the immune mechanisms of defense against fungal infections, it is accepted now that cell-mediated immunity is the main mechanism of defense. [2]
There may be a history of malnutrition. Malnutrition disrupts the function of immune system components. This weakens the immune system defense. The depressed immunity results in the pathogenic growth of Malassezia yeast. [2]
References
  1. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  2. MARKS, R. ROXBURGH'S Common Skin Diseases. 17th Ed. Arnold. 2003, 37-39.
  3. GRAHAM-BROWN, Robin and BURNS, Tony. Lecture notes : Dermatology. 10th Ed. Willy-Blackwell. 2011, 38-39.
  4. KLIEGMAN, Robert M. MARCDANTE, Karen J. JENSON, Hal B. and BEHRMAN, Richard E. NELSON Essentials of Pediatrics. 5th Ed. Elsvier. 2006, 474-476.
  5. SANTANA, Juliano Oliveira. DE AZEVEDO, Fernanda Luiza Andrade and FILHO, Pedro Costa Campos. Pityriasis versicolor: clinical-epidemiological characterization of patients in the urban area of Buerarema-BA, Brazil. ANAIS BRASILEIROS DERMATOLOGIA- Official publication of Brazilian Society of Dermatology. 2013[viewed on 24 march 2014]; 88(2): 216–221. Available from: doi: 10.1590/S0365-05962013000200005 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3750883/

Examination

Fact Explanation
Numerous, well marginated, oval to irregularly shaped macules scattered across the skin. Initially appears as oval to round macules and as the macules coalesce, they form irregular shapes. [1],[2]
Predominantly involving the upper trunk. Skin regions of chest, back and axillae are commonly affected. Pityriasis versicolor is caused by lipophillic organisms.The mentioned areas in the body have more sebaceous glands; therefore these regions are more commonly involved. But the lesions may appear anywhere on the body. [1],[2],[5]
Light scraping over lesion produces fine scales. Pityriasis Versicolor is a superficial fungal infection localized to stratum corneum. Light scraping can easily remove Keratin scales over the Lesions. [1],[2]
Hyperhydrosis. Local hyperhidrosis affects many young adults, most commonly noted are palms, soles and axillae. Increased rates of sweating and sebum secretion encourages the growth of the causative organism. [2], [3],
Features of Cushings syndrome. Children with Cushing's syndrome have a suppressed immunity. Pityriasis versicolor is more common in children with immunodeficiencies due to their weak defense mechanisms against fungal infections. Therefore features of Cushing's syndrome such as central obesity, buffalo hump, moon face, acne, purple skin striae and hypertension may be noted during examination. [4]
Features of malnutrition. Features of macro and micronutrient deficiencies such as dry eyes, pale conjunctiva Bitot's spots, angular stomatitis, cheilosis, glossitis, spongy bleeding gums, brittle hair, poor wound healing may be positive findings on general examination. [4]
References
  1. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  2. MARKS, R. ROXBURGH'S Common Skin Diseases. 17th Ed. Arnold. 2003, 37-39.
  3. GRAHAM-BROWN, Robin and BURNS, Tony. Lecture notes : Dermatology. 10th Ed. Willy-Blackwell. 2011, 38-39.
  4. KLIEGMAN, Robert M. MARCDANTE, Karen J. JENSON, Hal B. and BEHRMAN, Richard E. NELSON Essentials of Pediatrics. 5th Ed. Elsvier. 2006, 147-156, 823 .
  5. SANTANA, Juliano Oliveira. DE AZEVEDO, Fernanda Luiza Andrade and FILHO, Pedro Costa Campos. Pityriasis versicolor: clinical-epidemiological characterization of patients in the urban area of Buerarema-BA, Brazil. ANAIS BRASILEIROS DERMATOLOGIA- Official publication of Brazilian Society of Dermatology. 2013[viewed on 24 march 2014]; 88(2): 216–221. Available from: doi: 10.1590/S0365-05962013000200005 http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3750883/

Differential Diagnoses

Fact Explanation
Seborrheic dermatitis In comparison with Pityriasis, This is a papulosquamous disease which manifests on sebum rich areas of the scalp, face and trunk and it is relatively more erythematous. The severity can range from mild dandruff to exfoliative dermatitis which produces greasy scales with inflamed skin underneath. [1],[2]
Erythrasma Characteristically involving the body folds which are warm and moist. The lesions may initially appear as erythematous patches; however, they may progress to appear as though raised in relation to the surrounding skin and may display a brownish colour with apparent central clearing. [3] Erythrasma is commonly asymptomatic, but may occasionally be pruritic. [1]
Pityriasis alba Appears as poorly marginated hypopigmented patches often affecting the cheeks. Occasionally there may be fine superficial scaling. [1]
Pityriasis rosea It usually initially develops as a single plaque. It is larger (2-5 cm) than subsequent lesions and is rounder, redder and more scaly. A few days after the appearance of the initial lesion, smaller plaques appear, commonly on the trunk. Many patients complain of itching. [1],[2],[3]
Tinea corporis This is a superficial dermatophyte infection. It commonly presents as a pruritic, annular, scaly plaque with central clearing. The lesion may rapidly enlarge. It may rarely present with purpuric macules. [1],[2]
Vitiligo Is an acquired disorder of pigmentation of the skin presenting with well demarcated amelanotic macules; commonly white in colour. Initial lesions usually appear on hands, feet and face. This is commonly associated with other auto-immune diseases. These features are unique to vitiligo. [1],[2]
Guttate Psoriasis Presents with acute eruption of small papules of salmon pink color. Usually associated with fine scaling and mild pruritus. [1],[2]
Leprosy Characteristic peripheral sign first to appear is a hypopigmented plaque with loss of sensation over it. [1],[2]
References
  1. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  2. KUMAR, Parveen and CLARK, Michael. KUMAR & CLARK'S Clinical Medicine. 8th Ed. Elsevier. 2012, 130-132,1200-1202,1206,1207-1211,1229.
  3. HOLDINESS Mack R, Erythrasma and Common Bacterial Skin Infections. Letters to the Editor, American Family Physician [online] 15 January 2003, vol. 15;67(2):254 [viewed 25 May 2014] Available from: http://www.aafp.org/afp/2003/0115/p254.html

Investigations - for Diagnosis

Fact Explanation
Wood's lamp examination The Wood's lamp examination is a test that uses long wave ultraviolet light to closely examine the skin. It shows the coppery orange or apple green fluorescence of Pityriasis Versicolor. [1],[3]
Light microscopic examination This is the confirmatory investigation. Scrapings prepared with 20% Potassium hydroxide (KOH) are examined with a light microscope. The spores with short branched hyphae gives the typical 'Spaghetti and meatballs ' appearance. [2]
Culture Culture is not helpful as special media are required and as a result are performed rarely as diagnosis can be achieved with light microscopic examination of slides prepared with KOH. [2]
References
  1. VORVICK, L. J. Wood’s Lamp Examination. National Institutes of Health.2010. [Viewed 19 March 2014]. http://www.nlm.nih.gov/medlineplus/ency/article/003386.htm
  2. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  3. MARKS, R. ROXBURGH'S Common Skin Diseases. 17th Ed. Arnold. 2003, 37-39.

Management - General Measures

Fact Explanation
Explain the condition. Explain that Pityriasis versicolor is a benign fungal infection of the superficial skin. It is not contagious as it is due to a common commensal on the skin. It does not cause permanent scarring and can be treated successfully.The treatment will not immediately resolve the skin lesion; it may take up to several months. Recurrence is common. [1],[2]
Improve self hygiene. Bathing regularly, wearing clean dry clothes and washing garments regularly can effectively reduce recurrence rates. [1]
References
  1. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  2. GRAHAM-BROWN, Robin and BURNS, Tony. Lecture notes : Dermatology. 10th Ed. Willy-Blackwell. 2011, 38-39.

Management - Specific Treatments

Fact Explanation
Imidazole group of antifungals Applied locally at night to all affected areas for 2 - 4 weeks. (Eg. Clotrimazole, Miconazole, Econazole cream). These drugs interfere with fungal oxidative enzymes and results in lethal accumulation of hydrogen peroxide and reduces the ergosterol synthesis which is an important constituent of the fungal wall; therefore rendering the fungal wall permeable to intracellular constituents.[1], [2], [3]
Ketoconazol Shampoo Easy to use, non irritant and as effective as Selenium sulphide.It is recommend to use it monthly to prevent recurrences. [1], [2],[3]
Selenium suphide lotion This can be applied for 10 min and rinsed off. This is to be continued daily for 1 week. Is relatively less tolerable than Ketoconazole shampoo [1]
2.5% Selenium sulphide mixture in a detergent base Equally effective as Imidazole and cheaper. But it is irritant and not preferred in treating children. [1]
Systemic antifungals Oral Itraconazole, Fluconazole or Ketoconazole are used for wide spread lesions. These drugs show P450-mediated drug interactions [1], [2],[3]
References
  1. WELLER, Richard P.J.B. HUNTER, John A.A. SAVIN, John A. and DAHL, Mark V. Clinical Dermatology. 4th Ed. Blackwell Publishing, 2008, 254-256.
  2. KATZUNG, Bertram G. MASTERS, Susan B. and TREVOR, Anthony J. Basic and Clinical Pharmacology. 12th Ed. McGraw-Hill Companies, 2012, 853-855.
  3. BENNET, P.N. and BROWN, M.J. CLINICAL PHARMACOLOGY. 9th Ed. CHURCHILL LIVINGSTONE. 2003, 265-267.