L. Maccacaro

Utility of molecular identification in opportunistic mycotic infections: a case of cutaneous Alternaria infectoria infection in a cardiac transplant recipient.

ABSTRACT We report on a case of cutaneous infection caused by Alternaria infectoria in a cardiac transplant recipient. A rapid molecular diagnosis was obtained by sequence analysis of the internal transcribed spacer domain of the 5.8S ribosomal DNA region amplified from colonies developed on Sabouraud medium. Treatment consisted of a combination of systemic antifungal therapy, first with amphotericin B and then with itraconazole.

Diagnostic Aspects of Cutaneous Lesions due to Histoplasma capsulatum in African AIDS Patients in Nonendemic Areas

Histoplasmosis is a mycosis caused by a dimorphic saprophytic fungus, Histoplasma capsulatum, known as an environmental mould. Primary infection occurs through inhalation of spores, causing a self-limited disease in at least 95% of immunocompetent hosts. In immunocompromised individuals, especially patients with AIDS, Histoplasma capsulatum can produce progressive disseminated disease, which may prove fatal if untreated [1]. Two variants of Histoplasma capsulatum are known, namely, var. capsulatum, reported in the USA, Central and South America, and South Africa, and var. duboisii, reported exclusively in the African continent, i.e., West Africa (Senegal, Mali, Burkina-Faso, Ivory Coast) and Central and Equatorial Africa (Chad, Congo, Zaire). Even though Europe is not an endemic area 131 cases were reported between 1995 and 1999 in a survey of histoplasmosis (Ashbee R, oral presentation at the European Conference on Medical Mycology, Barcelona, 2000). An Italian survey reported 26 cases in the 1990s [2], and there have been several reports of disseminated histoplasmosis occurring in AIDS patients from Africa [3, 4, 5]. A review of the latest reports of African cases draws attention to the similarity of clinical presentation (particularly cutaneous involvement) among these cases compared with those occurring in South America. The pleomorphic presentation of the mucocutaneous lesions and the susceptibility of AIDS patients to opportunistic infections could delay the clinical and laboratory diagnosis in non-endemic areas. Therefore, a high index of suspicion is needed to make an early diagnosis and to permit rapid differentiation of the condition from most others with which disseminated histoplasmosis can be confused and thus misdiagnosed, i.e., secondary syphilis, AIDS-associated prurigo, cryptococcosis, candidosis, molluscum contagiosum and Penicillium marnefei disease. Reported here is the case of a 40-year-old black woman from Nigeria, who was diagnosed with HIV in January 2002 and who had immigrated to the Verona district of Italy in the year 2000. She was suffering from nephrotic syndrome and congestive edema of the nasal and pharyngeal mucosa. Until January 2002 she had been receiving antiretroviral therapy, but she failed to comply regularly with the administration regimen. In July 2002 she was admitted to our hospital with major labial and glottal edema and localized facial skin lesions, described as papular-ulcerative, that later spread to the arms and trunk. Her CD4+ lymphocyte count was 14 cells/mm3 and her T4/T8 score was 0.02%. Histopathology (Grocott’s and periodic acid-Schiff stain) of the skin biopsy sample revealed the presence of yeast-like elements measuring 3– 5 m in diameter. The definitive diagnosis was made by cultivation of the organism from skin biopsy in Sabouraud glucose agar at 24 C and brain heart infusion agar at 37 C to obtain the yeast phase. Isolation of the pathogen required 1–2 weeks, and identification was based on the evidence of specific warted macroconidia of Histoplasma capsulatum and conversion to the yeast phase. Positive urease activity differentiated var. capsulatum from var. duboisii. Confirmation was obtained using molecular identification as described previously [6]. Two pairs of PCR primers were first designed to develop a nested PCR assay to amplify the DNA region of Histoplasma capsulatum. These primers were based on the sequence of a gene coding for a 100-kDa-like protein unique to Histoplasma capsulatum deposited in the GenBank database (accession number AJ005963) [7]. Primers Hc I (50-GCG TTC CGA GCC TTC CAC CTC G. Lo Cascio ()) Servizio di Microbiologia, Azienda Ospedaliera di Verona, Ospedale Policlinico G.B. Rossi, Piazzale Scuro 10, 37134 Verona, Italy e-mail: giuliana.locascio@azosp.vr.it Tel.: +39-045-8074682 Fax: +39-045-584159

First Case of Bloodstream Infection Due to Candida magnoliae in a Chinese Oncological Patient

ABSTRACT We report a case of fungemia caused by Candida magnoliae, a yeast never associated with human disease. The infection occurred in a 42-year-old Chinese patient with gastric cancer complicated by peritoneal carcinosis. Multiple blood cultures were positive for yeast; the species was well identified with biochemical and molecular methods. The phylogenetic analysis showed a close relationship of C. magnoliae to Candida krusei.

Performance of different commercial methods for determining minimum inhibitory concentrations of glycopeptides and linezolid against blood isolates of Staphylococcus aureus

The aim of this study was to determine the accuracy of commercial systems (VITEK® 2, Etest and Sensititre®) in determining the minimum inhibitory concentrations of vancomycin, teicoplanin and linezolid of Staphylococcus aureus strains and to evaluate the reproducibility of each system in a clinical microbiology laboratory. In total, 115 strains of S. aureus isolated from blood cultures were tested with all three commercial methods as well as the broth microdilution method, which is designated as the standard for glycopeptides and linezolid. Fourteen different S. aureus strains were included in a reproducibility test for all methods and antibiotics. For these strains, antimicrobial susceptibility testing was repeated 10 times on different days with all four methods, each time using the same inoculum. All three commercial methods exhibited similar performance in categorisation of nearly all of the meticillin-susceptible S. aureus (MSSA) isolates. Discrepancies were registered for meticillin-resistant S. aureus (MRSA); 2.5% of the strains in the intermediate or resistant category with the VITEK 2 system were not recognised as resistant by Etest and Sensititre. Moreover, none of the three commercial methods provided accurate results compared with homemade broth microdilution. Reproducibility of vancomycin and teicoplanin was 100% with VITEK 2 and Sensititre and 98.75% with Etest. Microdilution showed a reproducibility of 95.6% with vancomycin and 83.1% with teicoplanin. In contrast to previous reports, the best agreement with microdilution was exhibited by VITEK 2 both for MSSA and MRSA. For the antibiotics tested, the best reproducibility was obtained with the VITEK 2 and Sensititre systems.

Caratterizzazione molecolare di una epidemia da Candida parapsilosis in terapia intensiva

Microbiologia Medica 243 contaminati da Achromobacter xilosoxidans (Ax). Dei 7 flaconi di clorexidina al 3%, 3 erano contaminati da Ax e 1 da Ralstonia paucula (Rp). Dei 4 flaconi in uso di Baxidin, 2 erano contaminati da Ax. Sono invece risultati tutti sterili i flaconi di Amuchina e Braunol. Nei successivi test Ax è cresciuto su agar sia dopo l’esposizione al Baxidin che alla clorexidina 1% e 3%. Quest’ultima, a queste concentrazioni si è rivelata inefficace anche nei confronti di Rp. Conclusioni. Achromobacter xilosoxidans e Ralstonia paucula appaiono resistenti ad alcuni disinfettanti di uso comune, tanto che in alcuni casi ne possono contaminare i flaconi.