Introduction Using the information obtained from analysis of 16S rRNA gene sequences,Tsukamurella was first proposed as a genus in 1988,1 despite the fact that the first strain of this group of bacteria was described ...Introduction Using the information obtained from analysis of 16S rRNA gene sequences,Tsukamurella was first proposed as a genus in 1988,1 despite the fact that the first strain of this group of bacteria was described in 1941,2 and the first human isolate was reported in 1971.3 Similar to related genera of the order Corynebacteriales,such as Nocardia,Rhodococcus,and Gordonia,members of Tsukamurella are Gram-positive,aerobic,catalase-positive,and partially acid-fast as a result of the presence of mycolic acid in the cell envelope.Due to their similar phenotypic properties,differentiation of these genera and speciation within these genera is difficult in most clinical microbiology laboratories.展开更多
Tsukamurella species are obligate aerobic,gram-positive,weak acid-fast,nonmotile bacilli.They are found in various environments,such as soil,water,sludge,and petroleum reservoir wastewater,and belong to the order Acti...Tsukamurella species are obligate aerobic,gram-positive,weak acid-fast,nonmotile bacilli.They are found in various environments,such as soil,water,sludge,and petroleum reservoir wastewater,and belong to the order Actinomycetales.In 2016,there was a reclassification of species within the genus Tsukamurella,merging the species Tsukamurella tyrosinosolvens(T.tyrosinosolvens)and Tsukamurella carboxydivorans.Tsukamurella species are clinically considered to be a rare opportunistic pathogen,because most reported cases have been related to bacteremia and intravascular prosthetic devices and immunosuppression.To date,it has been isolated only from human specimens,and has always been associated with clinical disease;human infections are very rare.Reported infections have included pneumonia,brain abscesses,catheter-related bloodstream infections,ocular infections,bacteremia,and sepsis presenting with septic pulmonary emboli in patients who are immunocompromised.To date,there is no commercially available test for identification.On the other hand,sequence-based identification,including matrix-assisted laser desorption ionization time-of-flight mass spectrometry,is an alternative method for identifying clinical isolates that are either slow growers or difficult to identify through biochemical profiling.The golden standards for diagnosis and optimal management still remain to be determined.However,newer molecular biological techniques can provide accurate identification,and contribute to the appropriate selection of definitive therapy for infections caused by this organism.Combinations of several antimicrobial agents have been proposed for treatment,though the length of treatment for infections has yet to be determined,and should be individualized according to clinical response.Immunocompromised patients often experience severe cases due to infection,and life-threatening T.tyrosinosolvens events associated with dissemination and/or failure of source control have occurred.Favorable prognoses can be achieved through earlier iden展开更多
基金This work is partly supported by funding from the Collaborative Innovation Center for Diagnosis and Treatment of Infectious Diseases,the Ministry of Education of China.
文摘Introduction Using the information obtained from analysis of 16S rRNA gene sequences,Tsukamurella was first proposed as a genus in 1988,1 despite the fact that the first strain of this group of bacteria was described in 1941,2 and the first human isolate was reported in 1971.3 Similar to related genera of the order Corynebacteriales,such as Nocardia,Rhodococcus,and Gordonia,members of Tsukamurella are Gram-positive,aerobic,catalase-positive,and partially acid-fast as a result of the presence of mycolic acid in the cell envelope.Due to their similar phenotypic properties,differentiation of these genera and speciation within these genera is difficult in most clinical microbiology laboratories.
文摘Tsukamurella species are obligate aerobic,gram-positive,weak acid-fast,nonmotile bacilli.They are found in various environments,such as soil,water,sludge,and petroleum reservoir wastewater,and belong to the order Actinomycetales.In 2016,there was a reclassification of species within the genus Tsukamurella,merging the species Tsukamurella tyrosinosolvens(T.tyrosinosolvens)and Tsukamurella carboxydivorans.Tsukamurella species are clinically considered to be a rare opportunistic pathogen,because most reported cases have been related to bacteremia and intravascular prosthetic devices and immunosuppression.To date,it has been isolated only from human specimens,and has always been associated with clinical disease;human infections are very rare.Reported infections have included pneumonia,brain abscesses,catheter-related bloodstream infections,ocular infections,bacteremia,and sepsis presenting with septic pulmonary emboli in patients who are immunocompromised.To date,there is no commercially available test for identification.On the other hand,sequence-based identification,including matrix-assisted laser desorption ionization time-of-flight mass spectrometry,is an alternative method for identifying clinical isolates that are either slow growers or difficult to identify through biochemical profiling.The golden standards for diagnosis and optimal management still remain to be determined.However,newer molecular biological techniques can provide accurate identification,and contribute to the appropriate selection of definitive therapy for infections caused by this organism.Combinations of several antimicrobial agents have been proposed for treatment,though the length of treatment for infections has yet to be determined,and should be individualized according to clinical response.Immunocompromised patients often experience severe cases due to infection,and life-threatening T.tyrosinosolvens events associated with dissemination and/or failure of source control have occurred.Favorable prognoses can be achieved through earlier iden
