ABSTRACT
In this study we investigated the epidemiology of a cluster of cutaneous infections owing to Aspergillus niger, which occurred in neutropenic patients in a bone marrow transplant unit. Heavy environmental contamination with the mould was found in the ward kitchen adjacent to the unit. The clinical and environmental isolates were typed by random amplification of polymorphic DNA (RAPD), which showed one of the patients was infected with the same strain as that isolated repeatedly from the kitchen area. In another case, contaminated stockinette material was implicated as the source of infection. Thorough cleaning of the ward kitchen resulted in no further cases on the unit. This highlights the fact that aspergilli may spread to patients by air, food or other vehicles, and underlines the importance of searching for a source and ensuring high levels of hospital hygiene are maintained.
Subject(s)
Aspergillosis/epidemiology , Aspergillosis/transmission , Aspergillus niger/isolation & purification , Cross Infection/epidemiology , Cross Infection/transmission , Dermatomycoses/epidemiology , Dermatomycoses/transmission , Disease Outbreaks , Equipment Contamination , Food Service, Hospital , Adult , Aged , Aspergillosis/microbiology , Aspergillus niger/classification , Aspergillus niger/genetics , Base Sequence , Cross Infection/microbiology , Dermatomycoses/microbiology , England/epidemiology , Female , Humans , Infection Control , Male , Middle Aged , Molecular Sequence Data , Neutropenia/complications , Random Amplified Polymorphic DNA TechniqueABSTRACT
This short report serves as a warning to the unwary of possible "pseudoclusters" of infection with Aspergillus fumigatus as shown by the typing system, random amplification of polymorphic DNA (RAPD). This was demonstrated by typing 10 epidemiologically distinct isolates of A fumigatus using two different preparations of Taq DNA polymerase. One of the enzymes did not discriminate between the isolates, giving the false impression that a cluster of infection had occurred. Enzyme source is thus a key variable when using RAPD to distinguish between isolates of A fumigatus.
Subject(s)
Aspergillus fumigatus/classification , DNA, Fungal/analysis , Mycological Typing Techniques , Base Sequence , DNA Primers , DNA-Directed DNA Polymerase , Gene Amplification , Humans , Molecular Sequence Data , RNA-Directed DNA Polymerase , Taq PolymeraseABSTRACT
Clusters of invasive infection with Aspergillus fumigatus are known to be associated with building works but studying the epidemiology has been hampered by the lack of a reliable typing system. A combination of three typing systems; silver staining of sodium dodecyl sulphate-polyacrylamide gels, immunoblot fingerprinting, and random amplification of polymorphic DNA (RAPD) was applied to seven cases on a haematology unit. The results show three of the patients to have indistinguishable isolates, suggesting a common source. Detection and removal of such sources, although difficult, would be an effective way of controlling the infection.
Subject(s)
Aspergillosis/epidemiology , Adult , Aged , Aspergillosis/microbiology , Aspergillus/classification , Cluster Analysis , Cross Infection/epidemiology , Cross Infection/microbiology , Female , Hospital Design and Construction , Humans , Male , Middle Aged , Mycological Typing TechniquesABSTRACT
A new method for fingerprinting Aspergillus fumigatus by random amplification of polymorphic DNA (RAPD) by using single primers with arbitrary sequences is described. Five primers were examined with 19 isolates from six patients with aspergilloma as well as with A. fumigatus NCPF 2109. Two of the primers (GCT GGT GG and GCG CAC GG, 5' to 3') gave adequate discrimination between isolates, generating five and six types, respectively. Combination of the results obtained with each of these two primers generated 12 types. This compares very favorably with immunoblot fingerprinting and XbaI-generated restriction fragment length polymorphisms on the same isolates. Typeability and reproducibility were good with RAPD, and RAPD was less labor-intensive than immunoblot fingerprinting. RAPD typing results suggested that aspergillomas sometimes contain isolates of more than one type.
Subject(s)
Aspergillus fumigatus/genetics , DNA Fingerprinting/methods , DNA, Fungal/genetics , Polymerase Chain Reaction/methods , Aspergillosis/microbiology , Aspergillus fumigatus/classification , Aspergillus fumigatus/isolation & purification , Base Sequence , Evaluation Studies as Topic , Humans , Molecular Sequence Data , Mycology/methods , Polymorphism, GeneticABSTRACT
Corynebacterium jeikeium causes septicaemia in neutropenic patients usually after colonizing intravenous lines. This paper reports the results of immunoblotting sera from 14 patients with a C. jeikeium septicaemia. Recovery from the septicaemia was associated with production of both IgM and IgG against antigenic bands of 50, 52 and 110 kDa. Antibody against the 110 kDa band was present in controls but the antibody against the 50 and 52 kDa was specific to those patients who had on-going or previous C. jeikeium infection. A case of C. jeikeium endocarditis is also presented and here recovery was associated with seroconversion to the 50 and 52 kDa bands.
