Pitiriasis versicolor por Malassezia pachydermatis: caso clínico / Pityriasis versicolor caused by Malassezia pachydermatis: clinical case

Se presenta un caso clínico de pitiriasis versicolor por M. pachydermatis en una paciente de 11 años de edad, diagnosticado mediante clínica, morfofisiología y biología molecular. Malassezia pachydermatis es parte de la microbiota común de diversos mamíferos domésticos y animales salvajes. En éstos se reconoce como agente causal de dermatitis y otitis externa. En humanos se han descrito escasas infecciones ya sea superficiales como invasoras, lo que puede atribuirse a la difícil transmisión y adaptación a partir de los animales domésticos. Se comentan los aspectos biológicos y epidemiológicos de esta infección zoonótica.

A clinical case of pityriasis versicolor caused by M. pachydermatis in an 11 year old patient which was diagnosed by means of clinic, morphophysiology and molecular biology is presented. Malassezia pachydermatis is part of regular microbiota in several domestic mammals as well as wild animals. It is recognized as the causing agent of dermatitis and external otitis in the latter. As to human beings, superficial infections have rarely been given an invasive character what can be explained by the difficult transmission and adaptation coming from domestic animals. Biological and epidemiological aspects of this zoonotic infection are described.

[Clinical-epidemiological aspects of pityriasis versicolor (PV) in a fishing community of the semiarid region in Falcon State, Venezuela]. / Aspectos clínico-epidemiológicos de la pitiriasis versicolor (PV) en una comunidad pesquera de la región semiárida del Estado Falcón, Venezuela.

Between August 2001 and May 2002, the prevalence and several epidemiological and clinical characteristics of pityriasis versicolor (PV) were studied in 902 individuals aged two months- 60 years, 426 females and 476 males, from a fishery community of Río Seco, a semiarid region in the state of Falcon, north-western Venezuela. The overall prevalence of the disease was 15.52% (140/902). The frequency of infection was higher in females (65.7% vs. 34.3%), children under one year of age and adolescents (27.9% y 32.1%, respectively), and dark skin (67.9%). The most commonly affected anatomical areas were the face (57.9%) and thorax (27.1%). The most important clinical features of the disease were: hypochromic (91.4%), multicentric (73.6%), pruritic (92.9%), fine scaled (80.7%) and irregularly shaped borders (91.4%). On the basis of these results, the possible risk factors on transmission dynamic and maintenance of the disease endemically is discussed.

Nosocomial Malassezia pachydermatis bloodstream infections in a neonatal intensive care unit.

Malassezia pachydermatis, a lipophilic yeast, has been described to cause sporadic nosocomial bloodstream infections (BSI). Nosocomial outbreaks of M. pachydermatis BSI have never been described. A cluster of M. pachydermatis BSIs in the neonatal intensive care unit at Louisiana State University Medical Center, University Hospital provided the opportunity to investigate the epidemiology of this organism and apply molecular epidemiologic typing techniques. A case-patient was defined as any neonatal intensive care unit patient in University Hospital with a blood culture positive for M. pachydermatis from January 1, 1989, through August 15, 1991. Five patients met the case definition. Case-patients were premature as estimated by gestational age and required prolonged hospitalization. Case-patients received parenteral nutrition and intravenous lipids for twice as many days as randomly selected controls. No environmental source of M. pachydermatis was identified; however, infants on each side of a previously identified M. pachydermatis-colonized infant became colonized with M. pachydermatis during a 20-day period. Chromosomal analysis of five M. pachydermatis blood isolates from two case-patients had identical banding patterns. These data show that M. pachydermatis can cause nosocomial BSI outbreaks, that premature infants receiving parenteral nutrition and/or lipids may be at greatest risk and that transmission is most likely from person to person, probably via the hands of medical personnel.