Diagnosis Of Pityriasis Versicolor Research Articles

Fungal coexistence in the skin mycobiome: a study involving Malassezia, Candida, and Rhodotorula

Evidence of fungal coexistence in humans points towards fungal adaptation to the host environment, like the skin. The human commensal Malassezia has evolved, especially residing in sebum-rich areas of the mammalian body where it can get the necessary nutrition for its survival. This fungus is primarily responsible for skin diseases like Pityriasis versicolor (PV), characterized by hypo or hyperpigmented skin discoloration and erythematous macules. In this manuscript, we report a 19-year-old healthy female who presented with a one-year history of reddish, hypopigmented, asymptomatic lesions over the chest and a raised erythematous lesion over the face. Upon clinical observation, the patient displayed multiple erythematous macules and erythematous papules over the bilateral malar area of the face, along with multiple hypopigmented scaly macules present on the chest and back. Based on the above clinical findings, a diagnosis of PV and Acne vulgaris (AV) was made. Interestingly, the patient was immunocompetent and didn’t have any comorbidities. Upon isolation of skin scrapings and post-culturing, we found the existence of three fungal genera in the same region of the patient’s body. We further went on to confirm the identity of the particular species and found it to represent Malassezia, Rhodotorula, and Candida. We report how Malassezia, the predominant microbial resident skin fungus, coexists with other fungal members of the skin mycobiome. This study on an applied aspect of microbiology also shows how important it is to identify the fungal organism associated with skin infections so that appropriate therapeutics can be advised to avoid cases of relapse.

Dermoscopic Assessment of Pityriasis Versicolor: A Cross-Sectional Observational Study

Objective: Pityriasis versicolor (PV) is usually a clinical diagnosis. In uncertain cases, PV is confirmed by microscopic examination with 10% potassium hydroxide (KOH). However, the KOH test is not 100% sensitive in diagnosing PV. Dermoscopy of PV is still an unexplored area with very little data reported. This study was planned to study the various dermoscopic features and their utility in the diagnosis of PV. Methods: This cross-sectional observational study was carried out over a 1-year period (September 2020–September 2021) among 57 patients with KOH-confirmed PV. All patients underwent dermoscopy using a handheld dermoscope (DermLite DL4; DermLite LLC). The chi-square test or Fisher’s exact test was used to analyze the data. Results: Of the 57 patients, 43 (75.44%) had the hypopigmented type, followed by the hyperpigmented type (n = 12, 21.05%) and the perifollicular type (n = 2, 3.51%). Nonuniform pigmentation was the most common dermoscopic finding observed in both patients with hypopigmented PV (n = 42, 97.67%) and hyperpigmented PV (n = 12, 100%) (P = 0.001). Scaling was the second most commonly observed finding; patchy scaling (n = 25, 58.13%) and perifollicular scaling (n = 13, 30.23%) were commonly seen in hypopigmented PV, while hyperpigmented PV showed more diffuse scaling (n = 6, 50.00%) (P = 0.04) followed by patchy scaling (n = 5, 41.66%). Dermoscopy showed unique “double-edged scales” in all lesions with furrow scaling (n = 11, 19.30%) after eliciting a positive evoked scale sign. Other interesting features seen in hypopigmented PV were hypopigmentation around the hair follicle (n = 24, 55.48%) (P = 0.001) and perilesional hyperpigmentation (the halo sign) (n = 15, 34.88%) (P = 0.04). Conclusion: We observed several dermoscopic findings in PV that can serve as useful clues for differentiating PV from other similar disorders.

Direct molecular analysis of Malassezia species from the clinical samples of patients with pityriasis versicolor.

Species identification of Malassezia using culture-dependent methods is time-consuming due to their fastidious growth requirements. This study aimed to evaluate a rapid and accurate molecular method in order to diagnose the pityriasis versicolor (PV) and identify Malassezia species from direct clinical samples. Skin scraping or tape samples from patients with PV and healthy volunteers as the control group were collected. Diagnosis of PV was confirmed by direct microscopic examination. The DNA extraction was performed according to the steel-bullet beating method. Polymerase chain reaction-restriction fragment length polymorphism assay using HhaI restriction enzyme was applied for the identification and differentiation of Malassezia species. The PCR method was able to detect Malassezia in 92.1% of specimens which were also confirmed with microscopic examination. Statistically, a significant association was observed between the results of the two assays (P < 0.001). Moderate agreement was identified between the two methods to diagnose the PV in both populations (Kappa: 0.55). Considering microscopic examination as the gold standard method for confirmation of PV, the sensitivity, specificity, positive predictive value, and negative predictive value values of the PCR assay for recognition of PV were 85%, 75%, 92%, and 60%, respectively. M. globosa and M. restricta were the most prevalent species isolated from patients. In this study, the two-step molecular method based on the amplification of the D1/D2 domain and digestion of the PCR product by one restriction enzyme was able to diagnose and identify Malassezia directly from clinical samples. Consequently, it can be said that the molecular-based method provides more facilities to identify fastidious species, such as M. restricta.

The correct nomenclature of Zirelí sign in the propaedeutics of pityriasis versicolor (in memoriam)

Aiming at disclosing the semiotic method used in the diagnosis of pityriasis versicolor, the authors go through the history of the creation of Zirelí sign, describing the method, its usefulness and practicality in dermatological clinical practice, whether public or private, and to give credit to the author of this semiological maneuver, in memoriam.

Clinicoepidemiological Profile of Pityriasis Versicolor in a Tertiary Care Hospital in Kathmandu, Nepal

Pityriasis versicolor (PV) also known as Tinea versicolor is a benign, chronic superficial fungal infection of the skin caused by Malassezia furfur. It is characterized by dyspigmented macules with fine branny scales. The purpose of this study was to assess the epidemiological profile and clinical pattern of PV in a group of patients visiting a tertiary care centre of Nepal. A descriptive cross-sectional study was carried out including 150 patients diagnosed to have PV at the outpatient dermatology department of Nepal Medical College Teaching Hospital. Patients with the diagnosis of PV were included in the study. A detailed history was taken and it was followed by a thorough clinical examination. The findings of history and clinical examinations were documented in a predesigned proforma. Statistical Package for the Social Sciences (SPSS) version 16 was used to tabulate the data and analyze the results. There was a slight male preponderance with maximum patients of the age group 11 – 20 years. A majority of patients were students. Forty three (28.7%) patients had similar problem in close contacts and 42% had recurrent disease. Wearing of occlusive synthetic clothing was the commonest predisposing factor. Upper chest and upper back were the most involved sites. Hypopigmented macules were the commonest lesions in 72.7%. Coexisting seborrheic dermatitis (commonly pityriasis capitis ) was present in 44.67% of patients. Clinicoepidemiological profile of PV in our setting is similar to many studies done mostly in India. But few findings differ which indicates the need for further studies in Nepal especially from Terai regions where the prevalence is expected to be more.

Dermoscopic pattern of pityriasis versicolor.

Background: Pityriasis versicolor (PV) is essentially a clinical diagnosis characterized by hypopigmented or hyperpigmented patches on the skin. Dermoscopy is gaining popularity as a noninvasive procedure for the diagnosis of different pigmentary and inflammatory disorders. However, scarce evidence exists on the dermoscopic pattern of PV.Objective: To describe the dermoscopic features of hypopigmented and hyperpigmented lesions of PV.Methods: Dermoscopic images of PV lesions located on different body sites were retrospectively evaluated for the presence of predefined criteria.Results: A total of 178 lesions from 125 patients were included in the study among which 164 lesions were hypopigmented and 14 lesions were hyperpigmented. Nonuniform pigmentation was the most common dermoscopic feature seen in both hypopigmented lesions (n=152, 92.68%) and hyperpigmented lesions (n=14, 100%). Scales were seen in 142 hypopigmented lesions (86.56%) and 13 hyperpigmented lesions (92.86%). Patchy scaling was more common in hypopigmented lesions (n=95, 57.92%) while scaling in the furrows was more common in the dermoscopy of hyperpigmented lesions (n=5, 35.71%). Inconspicuous ridges and furrows and perilesional hyperpigmentation were other significant features seen in dermoscopy of the lesions.Conclusion: To our knowledge, this is the first study describing the dermoscopic features of PV in such a large number of patients. Description of these new features adds valuable information and may help to establish dermoscopy as an important auxiliary tool for the diagnosis of PV.

Dermoscopy in the Evaluation of Pityriasis Versicolor: A Cross Sectional Study.

Background:Pityriasis versicolor (PV) is a superficial mycosis caused by Malassezia yeast; a lipophilic fungus. Dermoscopy may be a value addition in the diagnosis of PV in some cases, where results of KOH (potassium hydroxide) examination are ambiguous. There is paucity of Indian data on dermoscopy of PV.Materials and Methods:Thirty consecutive patients diagnosed clinically with pityriasis versicolor were recruited in this pilot cross sectional study. Patients were subjected to KOH mount of the skin scrapings from the lesions which were positive in all the patients. Dermoscopy was performed in all using Universal Serial Bus (USB) dermoscope [Dinolite AMZT 73915, Edge 3] and features were recorded for analysis.Results:Hypopigmented variant was the most common type (80%). Dermoscopic analysis revealed altered pigmentary network as most common finding (100%) followed by scaling seen in 25 cases (83.33%). Folliculocentric pattern was appreciated in 20 cases (66.67%). A characteristic contrast halo ring around the primary altered pigmentation was observed in 20 cases (66.67%). Invasion of hair follicles by yeast was evident in 6 patients (20%).Conclusion:Dermoscopy with characteristic features such as folliculocentricity, contrast halo sign, and yeast invasion of hair follicles can be a very useful aid in contributing towards diagnosing pityriasis versicolor.

Analysis of the incidence of dermatomycosis in Azerbaijani Republic during 2000-2016

Aim. To conduct epidemiological analysis of the incidence of dermatomycosis (superficial mycoses of skin and its appendages) in the Republic of Azerbaijan during 2000-2016, as well as clinical epidemiological monitoring during 2011-2016.&#x0D; Methods. Analysis of incidence of visits was performed in the Republican dermato-venerologic clinic, children's republican dermato-venerologic dispansary №3, city dermato-venerologic dispansary №1 of the Republic of Azerbaijan according to the forms of state statistical observation №9 («Information about predominantly sexually transmitted diseases, fungal skin infections and scabies») approved by the decree of Azerbaijan State Statistical Commission No. 72/5 issued on 04.12.2000. Clinical analysis of dermatomycosis incidence during 2011-2016 was performed based on the results of laboratory (microscopic) verification of mycelium of the fungus.&#x0D; Results. During 2000-2016 in the Republic of Azerbaijan steady increase of the incidence of superficial mycoses of skin and its appendages was observed. In 2000 the incidence was 2783. In 2016, 12 630 cases were recorded, which is the peak value and is 4.5 times higher than in 2000. Clinical analysis of incidence of superficial mycoses of skin and its appendages in 2011-2016 demonstrated that the diagnosis of pityriasis versicolor (keratomycosis) took the leading place (33.5%). The second place in the prevalence was taken by smooth skin mycoses (32.7%), the third place - by candidiasis (skin and visible mucous membranes - 17.1%), the fourth place - by onychomycosis (14.5%), and the last place - by mycosis of the scalp and face (2.2%). Young population (10-20 years) is susceptible to keratomycosis, and adult population (30-50 years) - to smooth skin mycosis. We suggest that it is related to climate-geographic features, increased insolation, and as a result - to sweating and to disordered lipid-alkaline protective skin barrier. To confirm our hypothesis further investigation is necessary.&#x0D; Conclusion. Incidence of superficial mycoses of skin and its appendages, increased by 4.5 times was revealed; the leading position in prevalence is taken by pityriasis versicolor, the second - by smooth skin mycoses and the third - by skin and visible mucous membranes candidiasis.

Lewandowski &amp; Lutz Syndrome: A Rare Case Entity

Epidermodysplasia verruciformis (EV), first described in 1922 by Lewandowski and Lutz, is a rare inherited genetic disease. The disease usually manifests in childhood with highly polymorphic, widespread lesions.We report a case of a fifteen year old boy, who presented to us with multiple flat topped, hypopigmented papules of a seven year duration on his body. He was diagnosed with EV on a skin biopsy, after ruling out differential diagnosis of pityriasis versicolor, verruca vulgaris and acrokeratosisverruciformis. The patient was resistant to known treatment options.Key message: sun protection and lifelong observation for diagnosis and improved prognosis of malignant or premalignant lesions of EV.

СОВРЕМЕННЫЙ ВЗГЛЯД НА РАЗНОЦВЕТНЫЙ ЛИШАЙ: НЕКОТОРЫЕ АСПЕКТЫ ПАТОГЕНЕЗА И КЛИНИЧЕСКИЕ ОСОБЕННОСТИ ТЕЧЕНИЯ В УСЛОВИЯХ ЖАРКОГО КЛИМАТА

Objective: Identify perspiration, skin pH, and clinical features in patients with pityriasis versicolor in conditions of torrid climate. Methods: In the period of 2008-2011 years, there were 110 patients examined with the diagnoses of pityriasis versicolor (Pityrosporum) in the local clinical hospital No. 1, in Dushanbe.They were 63.6% men (70 persons), and 36.4% – of them women (40 persons), which part of them were rural residents 53.6%, and others were urban residents – 46.4%. The highest number of cases of diseases has mentioned with people in the age of 17 to 35 years (80.9%). Control group comprised to 30 healthy persons. The diagnosis of pityriasis versicolor was determined based on positive Besnier’s symptoms, Balzer tests, yellowish-brown fluorescence at Wood’s light, as well as revealing of a typical microscopic picture of “spaghetti and meatballs”. Colorimetric method was used to determine the skin pH. For quality assessment of perspiration intensity in patients with pityriasis versicolor was used perspiration indicator IIP-01. Results: Erythematic-squamosal form was the most frequent recorded forms (73.7%) among the 9 clinical types. The expanded version of the pityriasis versicolor with typical localization of the affected areas made 80.9%, hyperpigmental form prevailed over hypopigmental form. Rare atypical forms of the disease (white spot type, erythrasmoid, urticarioid, lichenoid, ring-shaped, obliterated) were recorded in 11.8% of cases. 20.9% of patients had atypical localization of the pathological disease process on the face skin, axillary cavities, inframammary crease, inguinal fold, clunis, genitals, poples, dorslims of hands. In comparison with healthy persons which indicates perspiration and pH indicators 51.8 mA±0,46 and 5,33±0,004, patients with pityriasis versicolor had higher perspiration and pH in all tested areas and made the average of 60.1 мА±0,2 and 6,23±0,003 accordingly. Conclusion: Pityriasis versicolor is clinically polymorphyc. Along with the frequent forms, there are atypical forms with unusual localization of the disease process that may lead to diagnostic errors. Increased perspiration in torrid seasons causes to shift the skin pH in terms of alkaline content, and creates favorable environment for dissemination of Malassezia furfur. Keywords: Pityriasis versicolor, perspiration, pH, clinical development, atypical form.

Pityriasis Versicolor: Clinical Spectrum and Diagnosis

Pityriasis versicolor (PV) is caused by the fungus Malassezia, especially by Malassezia globosa. The predisposing factors for PV are heat, humidity, hyperhidrosis, oral contraceptives, stress, application of oily preparations, and treatment with corticosteroids. PV is found mainly on the seborrheic areas of the trunk, shoulders, upper aspects of the arms, and neck, but it may spread to the face, scalp, submammary areas, axillae, groin, skin folds, and buttocks. It is characterized by hyperpigmented, hypopigmented, or erythematous (versicolor), round-to-oval, finely scaling, thin plaques. Other less frequent clinical variants are papular, atrophic, imbricata, and pityriasis rubra pilaris-like presentations. The diagnosis of PV is usually made clinically with the aid of Wood’s light or dermoscopy. Direct microscopic examination, culture, biopsy, and molecular studies are among the laboratory diagnostic methods. Topical therapy is the treatment of choice for most patients. Systemic imidazole therapy is usually reserved for widespread or resistant cases.

A randomized double-blind, non-inferiority Phase II trial, comparing dapaconazole tosylate 2% cream with ketoconazole 2% cream in the treatment of Pityriasis versicolor

Objectives: The objective of this research was to evaluate the efficacy of a new antifungal imidazole, dapaconazole tosylate, in the treatment of Pityriasis versicolor (PV).Design and methods: Sixty patients with clinical and mycological diagnosis of PV were randomly assigned to receive either 1 g dapaconazole tosylate 2% cream or 1 g ketoconazole 2% cream. Treatments were applied once a day for 28 days. A dermatologist evaluated efficacy and safety daily, and weekly laboratorial tests were performed. The primary end point was a clinical and mycological cure of lesions after 28 days of treatment. The secondary end point was the time to clinical healing assessed by Kaplan–Meier analysis and Log-rank testing.Results: Fifty-three patients adhered to protocol rules. Clinical and mycological cure was achieved in 84.6% (22/26) and 92.6% (25/27) of patients treated with ketoconazole and dapaconazole, respectively (difference [effect size] = 8.0%, Standard error of difference: 8.69%, 95% CI: –6.3 to 22.3%). Median time to healing was 23.5 and 21 days for ketoconazole and dapaconazole, respectively (p = 0.126). Adverse events occurred only in ketoconazole-treated patients (13%; 4/30).Conclusion: Dapaconazole tosylate is non-inferior to ketoconazole when used at a dose of 20 mg/day for 28 consecutive days for the treatment of PV. Dapaconazole also demonstrated a good safety profile.

Pityriasis Versicolor (Tinea Versicolor) Due toMalassezia Furfur: A Case Report

A 22-year-old boy presented with 6 months history of asymptomatic hyperpigmented patches on the upper arms and trunk. Skin scrapings from the patches were subjected to 10% KOH wet mount which showed short, stout, blunt, curved hyphae and clusters of round yeast cells. Culture was put up on Sabouraud dextrose agar with olive oil overlay (SDA-0). Malassezia furfur was isolated from the culture. A diagnosis of Pityriasis versicolor was made which is an emerging fungal infection.

Successful Treatment of Protracted Malassezia Folliculitis Initially Misdiagnosed as Pityriasis Versicolor

© 2011 Elsevier 0196-4399/00 (see frontmatter) 45 Introduction Malassezia species are part of the normal human cutaneous flora, occurring mainly on the trunk and head, with the highest densities in post-pubertal adolescents (1). Except forMalassezia pachydermatis, the remaining six species require an exogenous source of lipid for growth, because they are unable to synthesize C14 to C16 fatty acids (1). Clinically,Malassezia species cause a variety of recurrent cutaneous infections, i.e., pityriasis versicolor, folliculitis, seborrheic dermatitis, and a spectrum of other dermatologic disorders (2). Catheter-related fungemia associated with administration of total parenteral nutrition through central venous catheters has also been documented, especially in premature neonates (3). In regard to cutaneous infections, we report here the occurrence of a protracted case ofMalassezia folliculitis in a college student, which was cured by the application of topical cream containing 2.5% selenium sulfide after the correct diagnosis of folliculitis was made rather than a diagnosis of pityriasis versicolor.

Malasseziayeast species isolated from Iranian patients with pityriasis versicolor in a prospective study

The goal of this study was to determine the prevalence of Malassezia species in pityriasis versicolor lesions and to examine if the range of species varies with patients characteristics such as: age, sex and family history and also clinical findings such as site and number of the lesions. In a prospective study from July 2006 to July 2007, the patients with a clinical diagnosis of pityriasis versicolor (n = 166) were asked to participate in the study. A total of 116 patients had positive culture for Malassezia species: M. globosa was found in 52 (31.3%) cases, M. furfur in 34 (20.5%) cases, M. pachydermatis in 12 (7.2%) cases, M. restricta in 12 (7.2%) cases, M. slooffiae in 6 (3.6%) cases. According to our data, M. globosa is the main species causing pityriasis versicolor, M. furfur was found to be the second-most frequent species. M. sympodialis and M. obtusa were not found in any case, and in 30.2% of patient's Malassezia culture was negative.

Rotundiform morphology during the first episode of pityriasis versicolor - a retrospective case-control study on a distinct clinical presentation

We report a retrospective case-control study to investigate whether the rotundiform variant of pityriasis versicolor (PV) is significantly associated with the first episodes of PV. Our setting was a dermatology clinic run by a consultant dermatologist. We retrieved medical records of all patients with PV between April 1, 2002 and March 31, 2005. We identified patients with lesions forming closed round circles. We excluded patients with uncertain diagnosis or diagnosis not substantiated by Wood's light examination or skin scrapings for potassium hydroxide examination. For each patient, we retrieved the medical record of the next patient of the same sex and similar age (± three years) with documented non-rotundiform PV and diagnosis substantiated by investigations as the control subject.80 patients were diagnosed as having PV during the record retrieval period. 18 had clinical descriptions or clinical photographs documenting rotundiform PV. Five were excluded owing to uncertain diagnosis, unclear clinical descriptions, or diagnoses unsubstantiated by examination under Wood's light or skin scrapings for potassium hydroxide examination. 13 had definite diagnosis of rotundiform PV. Ten agreed to attend clinic. The response rate was 76.9%. Ten age-and-sex pair-matched control subjects with non-rotundiform PV were recruited. Nine patients with rotundiform PV and two controls with non-rotundiform PV had their episode of PV representing their first episode of PV (p = 0.01; OR = 36.0, 95% CI: 2.2 - 866.9). We conclude that rotundiform PV is significantly associated with the first episode of PV. This phenomenon might be analogous to the herald patch being the primary lesion in pityriasis rosea.

Prevalence of pityriasis versicolor in young Italian sailors.

Pityriasis versicolor is a superficial fungal disease with a world-wide distribution, but there are few available studies on its prevalence in the general population. To assess the prevalence of pityriasis versicolor in a representative sample of young Italian sailors, evaluating the influence of habits and risk factors in the affected individuals. Young cadets (n = 1024: 975 men and 49 women, mean age 22 years) of the Italian Navy Petty Officers' School in Taranto were consecutively examined by the same observer. The diagnosis of pityriasis versicolor was based on clinical picture and/or Wood's lamp examination. All the subjects filled in a questionnaire about sport practice, swimming pool attendance, marching, presence of hyperhidrosis and a positive clinical history of pityriasis versicolor in the past. The affected individuals were also asked if they were aware of their skin lesions. Differences between answers of affected and unaffected subjects were tested by Fisher's exact P-value test, and odds ratios were calculated. Pityriasis versicolor was diagnosed in 22 subjects (2.1%), all men, of whom 15 (68%) were not aware of their condition. No statistical association was found between active pityriasis versicolor and sport practice, swimming pool attendance, marching or presence of hyperhidrosis. A significant association [odds ratio 8.7 (95% confidence interval 3.3-21.5); Fisher's exact P-value test P < 0.01] was documented between active pityriasis versicolor and a previous clinical history of pityriasis versicolor. The prevalence of pityriasis versicolor in this sample of young Italian sailors was not high, in agreement with the available surveys performed in the general population in temperate climates. Many affected subjects were not aware of their condition. The only important factor associated with pityriasis versicolor was a previous history of pityriasis versicolor. This observation could confirm the hypothesis that constitutional factors, e.g. seborrhoea and chemical constitution of sebum, may play a crucial role in temperate climates, leading to relapsing forms of this superficial mycosis.

Treatment of pityriasis versicolor with bifonazole shampoo: a randomized double-blind study

The application of a shampoo containing an antifungal agent is a convenient and useful means of treating pityriasis versicolor. The effect of bifonazole 1% shampoo on extensive pityriasis versicolor was assessed, and the optimal duration of treatment determined. A total of 30 patients with a diagnosis of pityriasis versicolor were allocated to one of three treatment groups (n = 10 each): (A) 2 days of bifonazole shampoo followed by 5 days of the vehicle only; (B) 7 days of bifonazole shampoo only; (C) 7 days of the vehicle only. Patients were seen after 1 and 6 weeks. Some of those showing no response after 1 week were treated 'openly' for 1 week with bifonazole shampoo. Four patients were lost to follow-up. After the first week, clinical and mycological cure was observed in ten patients, four (44%) in group A and six (75%) in group B, and an improvement in four patients, two in both group A and group B. Failure was seen in three group A patients and in all group C patients. Seven failed patients underwent 'open' treatment with bifonazole shampoo; after 1 week, six were cured and one showed no improvement. Two patients (one each from group A and group C) complained of a mild reversible pruritus. These findings indicate that bifonazole shampoo is significantly more effective than placebo in treating pityriasis versicolor; 7 days of treatment are preferable to 2 days.

SELENIUM SULFIDE IN TREATMENT OF PITYRIASIS VERSICOLOR

Pityriasis versicolor is a benign, noncontagious, superficial fungus infection of the skin caused by Malassezia furfur. The characteristic macular eruption usually appears on the upper trunk and shoulders, although it may involve other parts of the body. The color of the lesions may be pink, fawn colored, light brown, or whitish. Both discrete and confluent areas are commonly seen in the same patients. Gentle scraping of the surface produces a fine furfuraceous scale from which the diagnosis of pityriasis versicolor is established by demonstration of the presence of filaments and spores of Malassezia furfur in the scrapings. Microscopic identification of the causative organism is accomplished by examination of a wet potassium hydroxide perparation or by the use of the ink-potassium hydroxide stain. 1 The condition is most commonly observed during the summer months, but many cases are also seen during the cooler months of the year. Subjective symptoms are usually

PITYRIASIS VERSICOLOR

IT IS only when unusual clinical or mycologic manifestations are present that the diagnosis of pityriasis versicolor (tinea versicolor) is troublesome. The areas most likely to cause difficulty are the neck, scalp, groin and extremities. Mycologic variations occur in patients recently under treatment. In clinical diagnosis, the use of Wood's light is a valuable adjunct, particularly in determining the extent of involvement. In the laboratory, the etiologic agent is easily determined by direct examination of scales mounted in potassium hydroxide or lactophenol (a mixture ofphenol, U.S.P., 20 Gm.; lactic acid, 20 cc.; glycerin U.S.P., 40 cc., and distilled water, 20 cc.). Mounts in lactophenol may be examined immediately, without waiting for clearing. The slide may be sealed with some suitable substance and kept for some time. CLINICAL OBSERVATIONS The sites of lesions observed in the 47 cases forming the basis for this study are noted in the accompanying table.