The virulence of two strains of Sporothrix schenckii isolated from patients with lymphocutaneous or disseminated sporotrichosis were examined in BALB/c mice (Group 1 and 2, respectively). The mice ...were inoculated subcutaneously into the left hind footpad with 4×106 S. schenckii yeast cells in order to evaluate (i) the development of cutaneous lesions, (ii) signs of inactivity, (iii) weight loss, (iv) survival rates, (v) number of viable yeast cells in the lungs and spleen, (vi) splenic index, (vii) extent of organ lesions, and (viii) immunological responses. Comparison of the two groups showed more severe disease in Group 2 mice that developed significant weight and hair loss associated with inactivity and left hind footpad lesions that extended close to the testicular area. The histopathology and large number of viable microorganisms isolated from the spleen confirmed the higher invasive ability of this strain. Moreover, a decrease of an in vitro specific lymphoproliferative response and IFN-gamma production were observed over time in Group 2 mice. As a result, at the end of the experiment, the S. schenckii-antigen (Ss-Ag) response was considered negative with a stimulation index (SI)=2. In contrast, Group 1 mice presented a positive response to Ss-Ag (SI=14.1). These results confirm the existence of different virulence profiles in S. schenckii strains. In addition, the use of subcutaneous inoculation as a suitable route for verification of the pathogenicity of this fungus in the murine model was confirmed.
The identification of mycobacterial species in clinical isolates is essential for making patient care decisions. Polymerase chain reaction (PCR) restriction enzyme analysis (PRA) is a simple and ...rapid identification method, based on amplification of 441 bp of the
hsp65 gene and restriction with
BstEII and
HaeIII. As a contribution to the validation of PRA, a multicenter study was performed in eight laboratories located in Argentina, Brazil, Colombia, Chile, and Guadeloupe. Each laboratory received 18 coded isolates from the collection of the Institute of Tropical Medicine (Antwerp, Belgium), representing duplicates of nine laboratory strains:
Mycobacterium terrae CIPT 140320001,
Mycobacterium scrofulaceum CIPT 140220031,
Mycobacterium flavescens ATCC 14474,
Mycobacterium triviale ATCC 23292,
Mycobacterium nonchromogenicum ATCC 19530,
Mycobacterium chitae ATCC 19627,
Mycobacterium abscessus ATCC 19977,
Mycobacterium kansasii ATCC 12478, and
Mycobacterium peregrinum ATCC 14467. A detailed protocol including amplification, enzymatic digestion, and gel preparation was provided to each laboratory. Two laboratories identified correctly all 18 (100%) isolates, one identified correctly 17 (94.5%), two identified 14 (77.7%), one identified 11 (61%), and two identified 8 (44.4%) isolates. Errors detected in laboratories with more than 77% accuracy were associated with electrophoresis running conditions and an unspecific amplicon produced by a single strain. Lower accuracy was mainly related to inappropriate use of DNA markers and insufficient training in interpretation of patterns. In conclusion, the PRA method was readily implemented in some Latin American and Caribbean laboratories of mycobacteria, but improvements in critical points, as gel running conditions and training in interpretiation of patterns, are needed in order to improve accuracy. In others, improvement in critical points is still necessary.
To determine the prevalence and epidemiology of enteropathogens in acute infantile diarrhea, 500 infants ⩾12 months of age with diarrhea and 500 age-matched control subjects coming to a São Paulo ...emergency room were studied. Enteropathogens were identified in 55% of case infants and 10% of controls; enteropathogenic Escherichia coli (EPEC) of classic EPEC serotypes producing EPEC adherence factor (EAF) (26% of case infants), rotavirus (14%), Salmonella species (8%), enterotoxigenic E. coli (7%), and Shigella species (5%) were associated with diarrhea. Isolation of EAF+ classic EPEC decreased with increasing age of cases and peaked in spring, whereas rotavirus was least common in early infancy and peaked in fall and winter. Bloody stool had a 36% positive predictive value for Shigella infection. EAF+ classic EPEC were highly resistant to antimicrobial drugs. Among poor São Paulo infants, EAF+ classic EPEC equaled or exceeded rotavirus throughout the year as a cause of diarrhea bringing children to medical attention.
Skin changes in pediatric transplant patients Manzoni, Ana Paula Dornelles da Silva; Kruse, Ricardo Lapa; Troian, Carina ...
Pediatric transplantation,
March 2006, Letnik:
10, Številka:
2
Journal Article
Recenzirano
: The advent of organ transplantation identified a new group of diseases. Dermatologists are studying transplant‐associated diseases along with the atypical behavior of already known dermatoses. ...Pediatric patients have been treated as an extension of adult population, but unique aspects of age required clarification. A prospective cohort was studied including patients from both genders up to 17 yr of age who were recipients of kidney, liver or BMT during 2003 in Porto Alegre, Brazil. Regular skin examinations were performed up to the sixth month after the procedure, and an analysis was determined by ID (i.e. = number of skin changes/number of patients‐month × 100). Thirty‐nine patients were examined: 20 were kidney transplant recipients; 11 were BMT recipients (10 autologous transplants and 1 allogeneic transplant); and 8 were liver transplant recipients. Skin changes result primarily from the use of medication (87.2). Individually, kidney transplant patients presented the highest ID of skin changes because of medications (104.1). BMT recipients presented the highest ID of alterations occurring on skin appendages (85.4) and liver transplant recipients had the highest ID of vascular changes (94.9). In conclusion, this study shows that cutaneous alterations in pediatric transplant recipients present some particularities not described in adult recipients, such as ichthyosiform xerosis in renal recipients and skin scaling with pellagroid appearance in bone marrow recipients. Also, dermatoses secondary to medication use were the main finding in pediatric population.