Biomedical subjects

Roma Batra

Publications and source records attributed to Roma Batra.

8 recordsLinked to original sources

PubMed2005

Malassezia Baillon, emerging clinical yeasts.

The human and animal pathogenic yeast genus Malassezia has received considerable attention in recent years from dermatologists, other clinicians, veterinarians and mycologists. Some points highlighted in this review include recent advances in the technological developments related to detection, identification, and classification of Malassezia species. The clinical association of Malassezia species with a number of mammalian dermatological diseases including dandruff, seborrhoeic dermatitis, pityriasis versicolor, psoriasis, folliculitis and otitis is also discussed.

Animals↗

PubMed2005

Pityriasis versicolor: a review of pharmacological treatment options.

Pityriasis versicolor is a common disorder of the skin, which is characterised by scaly hypo- or hyperpigmented lesions on the body. The lipophilic yeast, Malassezia, is considered to be the aetiological agent of this disease. A number of treatment options, both topical and systemic, have been shown to be effective. A critical evaluation of treatment options is presented.

Administration, Cutaneous↗

PubMed2004

Skin diseases associated with Malassezia species.

The yeasts of the genus Malassezia have been associated with a number of diseases affecting the human skin, such as pityriasis versicolor, Malassezia (Pityrosporum) folliculitis, seborrheic dermatitis and dandruff, atopic dermatitis, psoriasis, and--less commonly--with other dermatologic disorders such as confluent and reticulated papillomatosis, onychomycosis, and transient acantholytic dermatosis. Although Malassezia yeasts are a part of the normal microflora, under certain conditions they can cause superficial skin infection. The study of the clinical role of Malassezia species has been surrounded by controversy because of their fastidious nature in vitro, and relative difficulty in isolation, cultivation, and identification. Many studies have been published in the past few years after the taxonomic revision carried out in 1996 in which 7 species were recognized. Two new species have been recently described, one of which has been isolated from patients with atopic dermatitis. This review focuses on the clinical, mycologic, and immunologic aspects of the various skin diseases associated with Malassezia. It also highlights the importance of individual Malassezia species in the different dermatologic disorders related to these yeasts.

Dermatitis, Atopic↗

PubMed2004

Identification and typing of Malassezia species by amplified fragment length polymorphism and sequence analyses of the internal transcribed spacer and large-subunit regions of ribosomal DNA.

Malassezia yeasts are associated with several dermatological disorders. The conventional identification of Malassezia species by phenotypic methods is complicated and time-consuming, and the results based on culture methods are difficult to interpret. A comparative molecular approach based on the use of three molecular techniques, namely, amplified fragment length polymorphism (AFLP) analysis, sequencing of the internal transcribed spacer, and sequencing of the D1 and D2 domains of the large-subunit ribosomal DNA region, was applied for the identification of Malassezia species. All species could be correctly identified by means of these methods. The results of AFLP analysis and sequencing were in complete agreement with each other. However, some discrepancies were noted when the molecular methods were compared with the phenotypic method of identification. Specific genotypes were distinguished within a collection of Malassezia furfur isolates from Canadian sources. AFLP analysis revealed significant geographical differences between the North American and European M. furfur strains.

Animals↗

PubMed2004

Etiology and management of Seborrheic dermatitis.

Seborrheic dermatitis (SD) is a common dermatological disorder that varies greatly in severity between individuals and with time. The etiology of this disease is poorly understood. Early investigators focused on the role of Malassezia (previously Pityrosporum) yeasts in the development of SD. Some researchers have hypothesized that there is an immunological component to SD and that this disease is caused by an altered immune response to Malassezia yeasts. However, other researchers view this condition as the result of hyperproliferation. Both antifungal and anti-inflammatory preparations have been used to treat SD effectively and safely. The wide range of antifungal formulations available (creams, shampoos, oral drugs) provides safe, effective and flexible treatment options for SD.

Adolescent↗

PubMed2004

Role of antifungal agents in the treatment of seborrheic dermatitis.

Seborrheic dermatitis is a superficial fungal disease of the skin, occurring in areas rich in sebaceous glands. It is thought that an association exists between Malassezia yeasts and seborrheic dermatitis. This may, in part, be due to an abnormal or inflammatory immune response to these yeasts. The azoles represent the largest class of antifungals used in the treatment of this disease to date. In addition to their antifungal properties, some azoles, including bifonazole, itraconazole, and ketoconazole, have demonstrated anti-inflammatory activity, which may be beneficial in alleviating symptoms. Other topical antifungal agents, such as the allylamines (terbinafine), benzylamines (butenafine), hydroxypyridones (ciclopirox), and immunomodulators (pimecrolimus and tacrolimus), have also been effective. In addition, recent studies have revealed that tea tree oil (Melaleuca oil), honey, and cinnamic acid have antifungal activity against Malassezia species, which may be of benefit in the treatment of seborrheic dermatitis. In cases where seborrheic dermatitis is widespread, the use of an oral therapy, such as ketoconazole, itraconazole, and terbinafine, may be preferred. Essentially, antifungal therapy reduces the number of yeasts on the skin, leading to an improvement in seborrheic dermatitis. With a wide availability of preparations, including creams, shampoos, and oral formulations, antifungal agents are safe and effective in the treatment of seborrheic dermatitis.

Administration, Cutaneous↗

PubMed2003

Seborrheic dermatitis.

Seborrheic dermatitis is present in 1% to 3% of immunocompetent adults, and is more prevalent in men than in women. Seborrheic dermatitis may be seen in conjunction with other skin diseases, such as rosacea, blepharitis or ocular rosacea, and acne vulgaris. Malassezia yeasts have been associated with seborrheic dermatitis. Abnormal or inflammatory immune system reactions to these yeasts may be related to development of seborrheic dermatitis. Treatment modalities for seborrheic dermatitis include keratolytic agents, corticosteroids, and more recently, antifungal agents. Antifungal agents do not carry a risk of skin atrophy or telangiectasia with prolonged use, and it is more prudent to consider antifungals than corticosteroid preparations. The wide range of antifungal formulations available (creams, shampoos, or oral) provides safe, effective, and flexible treatment options for seborrheic dermatitis.

Administration, Cutaneous↗

PubMed2003

Pityriasis versicolor.

Pityriasis versicolor is a mild or chronic condition characterized by scaly hypopigmented or hyperpigmented lesions usually affecting the trunk. The lesions vary depending on tropical or temperate climates. The disease seems to occur mainly at adolescence when the sebaceous glands are more active. Malassezia yeasts have been implicated in the pathogenesis of this disease. The mycelial form of the fungus has been suggested to be the cause of lesions. Antifungal preparations have been used to treat the initial presentation effectively, although in a proportion of patients the disease tends to reoccur. They are available in a wide range of formulations and have been shown to be safe.

Administration, Cutaneous↗