Nocardia Brain Abscess in a Liver Transplant Recipient

Nocardia brain abscess is rare. We report on a unique case of N. farcinica brain abscess in a liver transplant recipient, following Aspergillus fumigatus pneumonia. A 43-year-old liver transplant recipient presented with altered mentality at 2 months after A. fumigates pneumonia. He was successfully treated with surgical removal and antibiotic therapy with trimethoprim-sulfamethoxazole and ceftriaxone.     

Infected Aortic Graft

A case of infected aortic graft after abdominal aorta aneurysm resection is reported and a short review of this potential lethal complication is given.     

Diagnosis and management of nocardiosis after bone marrow stem cell transplantation in adults: Lack of lymphocyte recovery as a major contributing factor

Hematopoietic cell transplantation (HCT) is a curative treatment for hematological malignancies. This therapeutic approach is associated with a profound immune deficiency and an increased rate of opportunistic infections. Nocardiosis is a rare bacterial infection occurring mainly in patients with deficient cell-mediated immunity, such as AIDS patients or transplant recipients. Diagnosis of nocardiosis can be challenging, as signs and symptoms are non-specific. Routine prophylaxis with trimethoprin/sulfamethoxazole (TMP/SMZ) does not prevent the risk of infection. Between May 2001 and December 2009, five cases of nocardiosis were diagnosed from the 366 allogeneic HCT recipients in our centre. Four patients developed a disseminated nocardiosis within the first year after HCT. The fifth patient presented a localized cutaneous nocardiosis. In disseminated cases, median total CD4+ T-cells were below 100 cells/μL. Naive CD4+ CD45RA+/RO− T-cells were almost undetectable. CD8⁺ T-cells and NK cells were below the normal range and CD19+ B-cell reconstitution was completely deficient. In a localized case, we observed a lack of naive thymic emigrants CD4+ CD45RA+/RO− T-cells.     

奴卡菌感染16例诊治分析

目的探讨奴卡菌感染的临床表现、诊断、治疗及预后,以供临床诊治参考。方法对16例奴卡菌感染的临床表现、诊断、治疗及预后进行回顾性分析。结果 16例奴卡菌感染患者均有基础疾病及应用肾上腺糖皮质激素后发病;肺部病变最常见(68.8%);皮下组织感染均形成多发性瘘管;细菌培养75%为星形奴卡菌;治疗首选磺胺类药物;治愈11例,好转2例,死亡3例。结论奴卡菌感染是外源性、机会性感染,病原菌的分离和鉴定是诊断本病的首要条件。应及早使用磺胺类或敏感药物治疗,皮下软组织感染应予外科辅助治疗。预后与基础疾病的严重程度有关,早期诊断与治疗可降低本病死亡率。     

一株马鼻疽诺卡菌临床分离株的鉴定

目的应用基因测序分析进行诺卡菌（Nocardia farcinica）鉴定。方法将临床分离菌株BJ7菌株与诺卡菌标准参照菌株AY756551和结核分枝杆菌H37Rv接种L-J、PNB/TCH鉴别培养基。用生长良好的培养物提取全基因组DNA。设计引物,对rpoB、16S rDNA基因片段进行PCR扩增,对其PCR产物进行测序和网上同源性比对。结果 PNB/TCH鉴别培养基鉴定BJ7为非结核分枝杆菌,进化树中BJ7 16S rDNA序列亲缘关系与诺卡菌标准参照菌株AY756551比较相近,且16S rDNA和rpoBDNA序列与马鼻疽诺卡菌同源性极高,分别达到100%和99%。结论从结核病患者分离的菌株BJ7为马鼻疽诺卡菌。DNA测序分析能够快速、简便、准确地鉴定诺卡菌。     

Pneumocystis jirovecii pneumonia is rare in renal transplant recipients receiving only one month of prophylaxis

Prophylaxis against Pneumocystis jirovecii pneumonia (PCP) is recommended for at least 4–12 months after solid organ transplant. In our center, renal transplant recipients receive only 1 month of post‐transplant trimethoprim–sulfamethoxazole, which also may provide limited protection against Nocardia. We identified only 4 PCP cases and 4 Nocardia cases in 1352 patients receiving renal and renal‐pancreas transplant from 2003 to 2009 at the University of Michigan Health System. Two PCP cases were identified <1 year after transplant, and 2 PCP cases were identified >1 year after transplant (gross attack rate 4/1352, 0.3%). Two Nocardia cases were identified <1 year after transplant, and 2 cases were identified >1 year after transplant. All identified cases received induction therapy (7 of 8 with anti‐thymocyte globulin), whereas about one‐half of all renal transplant patients received induction therapy at our institution. No patient was treated for rejection within 6 months of PCP; 2 of 4 patients with PCP had recent cytomegalovirus infection. All patients with PCP and 3 of 4 patients with Nocardia survived. The benefits of prolonged PCP prophylaxis should be weighed against the adverse events associated with prolonged use of antimicrobials.     

Epidemiology and in vitro antimicrobial susceptibility of aerobic Actinomycetales in a clinical setting

IntroductionThe incidence of infections caused by aerobic actinomycetes is increasing. Recent changes in taxonomy and the variability in susceptibility patterns among species make necessary a proper identification and antibiotic susceptibility testing.Material and methodsFifty-three strains of aerobic actinomycetes were identified by MALDI-TOF MS using the VITEK MS Mycobacterium/Nocardia kit (bioMérieux, France) in a tertiary hospital in Spain during a six-year period. Antimicrobial susceptibility testing of the isolates was performed using the Sensititre Rapmycoi microdilution panel (Thermo Fisher Scientific, Massachusetts, USA).ResultsForty strains of Nocardia spp. were identified in the study, being N. farcinica and N. cyriacigeorgica the most prevalent ones. All isolates were susceptible to linezolid and the resistance to amikacin was only observed in one isolate of Gordonia sputi. Resistance to cotrimoxazole was only found in five isolates.ConclusionsRoutine identification and antimicrobial susceptibility testing of aerobic actinomycetes is advisable for an efficient identification of species and effective treatment.     

From the Cover: A unique basaltic micrometeorite expands the inventory of solar system planetary crusts

Micrometeorites with diameter ≈100–200 μm dominate the flux of extraterrestrial matter on Earth. The vast majority of micrometeorites are chemically, mineralogically, and isotopically related to carbonaceous chondrites, which amount to only 2.5% of meteorite falls. Here, we report the discovery of the first basaltic micrometeorite (MM40). This micrometeorite is unlike any other basalt known in the solar system as revealed by isotopic data, mineral chemistry, and trace element abundances. The discovery of a new basaltic asteroidal surface expands the solar system inventory of planetary crusts and underlines the importance of micrometeorites for sampling the asteroids'' surfaces in a way complementary to meteorites, mainly because they do not suffer dynamical biases as meteorites do. The parent asteroid of MM40 has undergone extensive metamorphism, which ended no earlier than 7.9 Myr after solar system formation. Numerical simulations of dust transport dynamics suggest that MM40 might originate from one of the recently discovered basaltic asteroids that are not members of the Vesta family. The ability to retrieve such a wealth of information from this tiny (a few micrograms) sample is auspicious some years before the launch of a Mars sample return mission.     

Cutaneous Nocardia brasiliensis infection in an immunocompetent host after ovarian cystectomy: A case study.

Nocardia brasiliensis is a rare human pathogen that is usually associated with localised cutaneous infections. We report a case of primary cutaneous Nocardia brasiliensis infection causing delayed wound healing that developed after ovarian cystectomy in an otherwise healthy 32-year-old woman. The patient was initially treated with cotrimoxazole, however due to intolerance intravenous amikacin was given and gradually the wound healed. The diagnosis was confirmed by demonstrating the causative organism in exudates, and cultures. Early diagnosis as well as early institution of chemotherapy is effective in most patients, and antimicrobial susceptibility testing of the isolate should be performed to identify the best treatment options.