Nocardia farcinica pericarditis after kidney transplantation despite prophylaxis

Abstract: A deceased-donor kidney transplant recipient developed purulent pericarditis caused by Nocardia despite trimethoprim–sulfamethoxazole (TMP–SMX) prophylaxis for Pneumocystis jirovecii . She was treated empirically with ceftriaxone and amikacin and subsequently underwent sternotomy with drainage of an intrapericardial abscess. Culture and susceptibility data demonstrated Nocardia farcinica , which was susceptible to SMX and amikacin, although resistant to ceftriaxone. Nocardia asteroides , the more common human pathogen, is generally susceptible to third-generation cephalosporins and TMP–SMX. N. farcinica is rare in the United States, more virulent and resistant than N. asteroides , and is more likely to cause disseminated disease. Successful therapy of disseminated Nocardia infections is dependent upon choice of appropriate empiric antibiotics in addition to surgical drainage of purulent fluid collections. TMP–SMX prophylaxis may not be sufficient to prevent infections due to Nocardia species in all immunosuppressed transplant recipients. Here, a rare complication of this unusual pathogen is discussed.     

Disseminated Nocardia otitidiscaviarum infection in a woman with sickle cell anemia and end-stage renal disease

Nocardia otitidiscaviarum is an uncommon human pathogen and a rare cause of pulmonary infection and bacteremia. We report a case of N. otitidiscaviarum bacteremia and pulmonary infection in a patient with end-stage renal disease (chronic kidney disease, stage 5) and sickle cell anemia. The epidemiology, pathogenesis, and treatment of Nocardia infections are discussed.     

Disseminated Nocardia transvalensis infection: an unusual opportunistic pathogen in severely immunocompromised patients.

Nocardia infections are infrequently recognized in humans. Nocardia species may cause severe life-threatening infections among immunocompromised patients and have been reported to cause actinomycotic mycetomas, primarily in tropical areas. Two severely immunocompromised patients had disseminated N. transvalensis infections. One had underlying X-linked variant chronic granulomatous disease and died of disseminated N. transvalensis infection, which was diagnosed only at postmortem examination. The second patient developed N. transvalensis pneumonia within 3 months of undergoing renal transplantation and died of disseminated mixed Pseudallescheria boydii and N. transvalensis infections. Thus, N. transvalensis may cause invasive and potentially fatal pulmonary and disseminated infections. Accordingly, clinical microbiology laboratories should become proficient in identifying this uncommon aerobic actinomycete.     

Salmonella bacteremia as manifestation of acquired immunodeficiency syndrome

Multiple opportunistic infections are characteristic of the acquired immunodeficiency syndrome (AIDS). Although bacterial pathogens have presented few problems, we have noted an emerging problem with salmonellal infection among patients with AIDS. A review of all stool and blood cultures from adults between January 1982 and July 1984 showed that 80 stool cultures were positive for Salmonella species; serogroup B was the most common isolated. Eight (10%) were isolated from patients with AIDS. Nineteen blood cultures were positive for Salmonella species. Six (32%) were isolated from patients with AIDS: three were positive for Salmonella serogroup B; two yielded Salmonella choleraesuis; and one yielded Salmonella serogroup D. In three (50%), Salmonella bacteremia was a presenting manifestation of AIDS. Bacteremias were recurrent in five patients. Thus, it appears that AIDS not only predisposes patients to serious salmonellal infections but also compromises their ability to eradicate these bacteria.     

Bacteremic disease due to Haemophilus influenzae capsular type f in adults: report of five cases and review

Five cases of bacteremic infections due to Haemophilus influenzae type f in adults are described, and previous reports of type f disease in nonpediatric patients are reviewed. Respiratory tract infections were most common in our series (two cases of pneumonia, one of epiglottitis, and one of nosocomial septicemia probably resulting from aspiration pneumonitis). All of these patients had factors predisposing them to respiratory tract infections, e.g., neurologic disease, congestive heart failure, or cigarette smoking. A fifth patient, who was bacteremic without an apparent primary focus, had dysgammaglobulinemia. Six episodes of bacteremia occurred in five patients; 11 of 13 cultures of blood obtained before parenteral antibiotic therapy were positive. All isolates were biotype I and susceptible to ampicillin. Antibiotic therapy was curative in cases of proved respiratory tract infection but failed in the setting of nosocomial septicemia, perhaps because of delayed initiation. The brevity of antibiotic treatment of the cryptogenic bacteremia permitted infection of a prosthetic vascular graft and recurrent bacteremia. Graft removal and repeated antibiotic therapy were curative.     

Trimethoprim/sulfamethoxazole-resistant Nocardia asteroides causing multiple hepatic abscesses. Successful treatment with ampicillin, amikacin, and limited computed tomography-guided needle aspiration

Hepatic abscesses are rarely encountered in disseminated Nocardia infections. Sulfonamides alone or trimethoprim/sulfamethoxazole is often efficacious in treating infections caused by Nocardia asteroides. In vitro resistance of N. asteroides to trimethoprim/sulfamethoxazole is occasionally present. The patient described in this report had disseminated nocardiosis initially manifesting as multiple subcapsular hepatic abscesses. In vitro susceptibility studies demonstrated resistance to trimethoprim/sulfamethoxazole. Subsequent treatment with ampicillin and amikacin in conjunction with computed tomography-guided needle aspiration of several of the hepatic abscesses, surgical drainage of a right pleural empyema, and eventual discontinuation of use of corticosteroids resulted in cure of the infection.     

Mycobacterium tuberculosis bacteremia in a university hospital.

SETTING: Patients with blood cultures positive for Mycobacterium tuberculosis between 1988 and 1999. OBJECTIVE: To study the clinical and microbiological characteristics of patients with tuberculous bacteremia, including data about evolution and management. DESIGN: Retrospective review of the clinical charts and microbiological records of patients with culture-proven tuberculous bacteremia between 1988-1999. RESULTS: During the study period, 19 patients with culture-proven M. tuberculosis bacteremia were detected (1.42 isolates/patient, 4.7% of all patients with blood cultures for mycobacteria). Four patients were non-infected with the human immunodeficiency virus and 15 were HIV-infected. In four patients blood was the only positive sample. Five patients were diagnosed simultaneously with tuberculosis and HIV infection. Only 13 had a temperature higher than 37.5 degrees C. Most patients had symptoms or signs of respiratory tract involvement, and 11 patients died (10 from tuberculosis). The average time for detection of positive blood cultures was 33.25 days for lysis-centrifugation cultures and 26.46 days for BACTEC cultures. The incidence of M. tuberculosis bacteremia remained stable during the study period. CONCLUSIONS: Although blood cultures are useful for definitive diagnosis of disseminated tuberculosis, the long incubation times made them of limited usefulness in the clinical management of patients. Mortality remains high in these patients.     

Difference in time to positivity is useful for the diagnosis of catheter-related bloodstream infection in hematopoietic stem cell transplant recipients

Catheter-related bloodstream infections are associated with recognized morbidity and mortality. Accurate diagnosis of such infections results in proper management of patients and in reducing unnecessary removal of catheters. We carried out a prospective study in a bone marrow transplant unit to assess the validity of a test based on the earlier positivity of central venous blood cultures in comparison with peripheral blood cultures for predicting catheter-related bacteremia. Between May 2002 and June 2004, 38 bloodstream infections with positive simultaneous central venous catheter and peripheral vein blood cultures were included. A total of 22 patients had catheter-related bacteremias and 16 had noncatheter-related bacteremias, using the catheter-tip culture/clinical criteria as the criterion standard to define catheter-related bacteremia. Differential time to positivity of 120 min or more was associated with 86% sensitivity and 87% specificity. In conclusion, differential time to positivity of 120 min or more is sensitive and specific for catheter-related bacteremia in hematopoietic stem cell transplant recipients who have nontunnelled short-term catheters.     

Port-A catheter-associated Nocardia bacteremia detected by gallium inflammation scan: a case report and literature review

Central venous catheter-associated Nocardia bacteremia is rarely reported. We present the case of a 48-y-old male with a history of advanced T-cell lymphoma who suffered from recurrent fever and persistent Gram-positive bacillus bacteremia. Port-A catheter-associated Nocardia bacteremia was diagnosed on the basis of the clinical response to removal of the catheter and the finding of increased gallium uptake, along with the Port-A catheter presented in the gallium inflammation scan.     

Infections due to Nocardia transvalensis: clinical spectrum and antimicrobial therapy.

Nocardia transvalensis, a rare Nocardia species, has previously been recognized as a cause of actinomycotic mycetoma. In a retrospective review of N. transvalensis isolates referred to the Centers for Disease Control (Atlanta) during the period January 1981 through January 1990, we identified 15 patient isolates. Four N. transvalensis isolates originated from one Australian reference laboratory; one patient's isolate that was identified by the Australian laboratory but that was not received at the Centers for Disease Control was also included in our study. A review of the cases of these 16 patients found that N. transvalensis caused infection in 10 patients and colonization in two patients. Six (75%) of eight patients with primary pulmonary or disseminated N. transvalensis infections had an underlying immunologic disorder or were receiving immunosuppressive therapy; three patients with disseminated infection died. All nine infected patients for whom specific antimicrobial therapy was prescribed received trimethoprim-sulfamethoxazole. Results of in vitro antimicrobial susceptibility tests of 11 N. transvalensis isolates revealed increased antimicrobial resistance to amikacin and other drugs when compared with that of other Nocardia species. Severely immunocompromised patients are predisposed to N. transvalensis pneumonia or disseminated infection, and the lung may be the portal of entry.     

Bacteremia and “Endotipsitis” following transjugular intrahepatic portosystemic shunting

AIM: To identify all cases of bacteremia and suspected endotipsitis after Transjugular intrahepatic portosystemic shunting (TIPS) at our institution and to determine risk factors for their occurrence. METHODS: We retrospectively reviewed records of all patients who underwent TIPS in our institution between 1996 and 2009. Data included: indications for TIPS, underlying liver disease, demographics, positive blood cultures after TIPS, microbiological characteristics, treat- ment and outcome. RESULTS: 49 men and 47 women were included with a mean age of 55.8 years (range 15-84). Indications for TIPS included variceal bleeding, refractory ascites,hydrothorax and hepatorenal syndrome. Positive blood cultures after TIPS were found in 39/96 (40%) patients at various time intervals following the procedure. Seven patients had persistent bacteremia fitting the definition of endotipsitis. Staphylococcus species grew in 66% of the positive cultures, Candida and enterococci species in 15% each of the isolates, and 3% cultures grew other species. Multi-variate regression analysis identified 4 variables: hypothyroidism, HCV, prophylactic use of an- tibiotics and the procedure duration as independent risk factors for positive blood cultures following TIPS (P < 0.0006, 0.005, 0.001, 0.0003, respectively). Prophylactic use of antibiotics before the procedure was associated with a decreased risk for bacteremia, preventing mainly early infections, occurring within 120 d of the procedure. CONCLUSION: Bacteremia is common following TIPS. Risk factors associated with bacteremia include failure to use prophylactic antibiotics, hypothyroidism, HCV and a long procedure. Our results strongly support the use of prophylaxis as a means to decrease early post TIPS infections.     

Mycobacterium neoaurum bacteremia in a hemodialysis patient.

Bacteremia due to Mycobacterium neoaurum, a rapidly growing mycobacterium, is described in a diabetic woman on hemodialysis. This is the first reported case of M neoaurum bacteremia in Canada. The organism initially grew on standard BacT/Alert SA aerobic blood cultures, and was subsequently positively identified using 16S rRNA sequence analysis. The present case serves to reinforce the need for a high index of clinical suspicion of infections caused by unusual microorganisms in the context of an immunocompromised host.     

Routine use of anaerobic blood cultures: are they still indicated?

PURPOSE: To determine the number of patients with bacteremia and fungemia and to evaluate the utility of routine anaerobic blood cultures as part of the work-up for suspected bacteremia. SUBJECTS AND METHODS: Retrospective review of microbiology data followed by selective chart review at a university-affiliated Veterans Affairs Medical Center. We determined the number of bacterial blood cultures drawn from January 1, 1994, to December 31, 1996, and the number of anaerobic, aerobic, and fungal isolates. Chart reviews were then performed on all patients with a positive anaerobic result.RESULTS: There were 6,891 sets of blood cultures processed through the laboratory, yielding 1,626 patients with positive results. Anaerobic isolates were recovered from 36 patients (2.2%) in 48 bottles. Aerobic isolates were recovered from 1550 patients (95.3%), and fungal isolates were recovered from 40 patients (2.5%). Seven patients (0.4%) had true anaerobic bacteremia. All seven patients had an obvious source of anaerobic infection that was known or suspected before the cultures were drawn. Antibiotic changes were made in four of these patients after the positive anaerobic results were known. Antibiotic changes led to clinical improvement in one patient. CONCLUSIONS: Routine use of anaerobic blood cultures rarely results in clinically important diagnostic or therapeutic benefits, based on the low incidence of anaerobic bacteremia in patients who are not at increased risk. Anaerobic blood cultures should be selectively ordered in patients at risk for anaerobic infections.     

First successful treatment of Nocardia farcinica brain abscess with moxifloxacin

Nocardia farcinica is an emerging pathogen in immunosuppressed patients causing both localized and disseminated infections. Many strains of this species are multidrug-resistant and require long-term antibiotic therapy, and consequently the choice of an oral treatment can be problematic. We report here the first case of successful treatment of N. farcinica brain abscess in a renal transplant recipient with an extended-spectrum fluoroquinolone, moxifloxacin.     

Mycobacterium neoaurum bacteremia in a hemodialysis patient

Bacteremia due to Mycobacterium neoaurum, a rapidly growing mycobacterium, is described in a diabetic woman on hemodialysis. This is the first reported case of M neoaurum bacteremia in Canada. The organism initially grew on standard BacT/Alert SA aerobic blood cultures, and was subsequently positively identified using 16S rRNA sequence analysis. The present case serves to reinforce the need for a high index of clinical suspicion of infections caused by unusual microorganisms in the context of an immunocompromised hostKey Words: 16S rRNA sequencing, Hemodialysis infection, Mycobacterium neoaurum The present report describes a case of Mycobacterium neoaurum bacteremia and arteriovenous shunt infection in a hemodialysis patient. M neoaurum, a member of the Mycobacterium parafortuitum complex, belongs to the group of rapidly growing environmental mycobacteria that are responsible for a broad spectrum of illnesses, including surgical wound and catheter infections, and disseminated cutaneous and pulmonary diseases (1). To our knowledge, this is the first case of infection due to M neoaurum reported in the Canadian literature.     

Aeromonas bacteremia in an elderly immunocompetent patient

We report the case of an elderly immunocompetent patient with Aeromonas hydrophila bacteremia without evidence of portal of entry. Despite several risk factors for a poor outcome, such as impaired renal function, two positive blood cultures, and community-acquired infections, the patient survived. Antimicrobial susceptibility was normal. Unknown polycystic liver disease was discovered and misdiagnosed as a hepatic abscess at the time of the bacteremia which was confirmed by repeated CT scans. Because of the absence of other risk factors for Aeromonas bacteremia, hepatic polycystic disease may take part in the onset of Aeromonas sp bacteremia as well as immunosenescence.     

Spurious elevated platelet counts associated with bacteremia

Spuriously elevated automated platelet counts secondary to in vivo bacteremia have not been reported previously. Two patients are described with blood cultures positive for Escherichia coli and Klebsiella pneumoniae, respectively, and bacteria present on peripheral blood smear. Those bacteria caused falsely elevated platelet counts to be generated by the Ortho ELT-8. These cases illustrate an unusual artifact and demonstrate that spurious counts can be generated by laser optical blood cell counters.     

Disseminated nocardiosis due to unusual species: two case reports

Pulmonary nocardiosis is the major clinical manifestation of human nocardiosis and disseminated infection can be seen in immunocompromised patients. N. asteroides is the predominant pathogen associated with disseminated diseases. We report 2 cases of pulmonary nocardiosis admitted with disseminated infection, caused by rare species of Nocardia: Nocardia transvalensis and Nocardia cyriacigeorgica.     

Disseminated Nocardia brasiliensis infection with septic arthritis.

An unusual case of disseminated Nocardia brasiliensis infection is presented. The patient, who had been receiving chronic dexamethasone therapy for 4 years, had pneumonia and septic arthritis of the left knee due to N. brasiliensis. To our knowledge, this is the first report from the United States of a synovial joint infection with this organism. Disseminated disease due to N. brasiliensis is infrequently reported; it is most often seen in the immunocompromised patient and is often unresponsive to therapy.     

Is anaerobic blood culture necessary? If so, who needs it?

BACKGROUND: The role of anaerobic blood cultures is not validated, although they are drawn routinely. METHODS: We performed a retrospective chart review at a private hospital in Japan for patients admitted between July 1, 2004 to June 30, 2005 to determine patient characteristics resulting in anaerobic blood culture. RESULTS: During the study period, 17,775 blood culture bottles were sent for the analysis, and 2132 bottles (12.0%) were positive for microbial growth. Bacteria were grown from 958 anaerobic bottles (44.7%), and 719 (33.7%) of those were judged to represent real infections, which accounted for 410 cases of bacteremia. Only 47 cases (11.5%) were detected by anaerobic cultures alone. Among those 47, obligate anaerobes represented 12 cases. Clinical evaluation could have predicted 7 of 12 cases of obligate anaerobic bacteremia. In the remaining 5 cases, the source of bacteremia was unclear. There were 2.7 cases of anaerobic bacteremia per 1000 blood cultures. The mortality attributable to anaerobic bacteremia was 50%. Among bacteremic cases not caused by obligate anaerobes yet diagnosed solely by anaerobic bottles, either the standard 2 sets of blood were not taken or their clinical outcomes were favorable. CONCLUSION: Anaerobic blood culture can be avoided in most cases. Anaerobic blood culture may be most helpful when (1) bacteremia because of obligate anaerobes is clinically suspected, (2) patients are severely immunocompromised, and (3) source of bacteremia is not identified by clinical evaluation.