HIV Encephalopathy Mimicking Acute Demyelinating Processes.

Human immunodeficiency virus (HIV) encephalopathy lies in the severe spectrum of HIV-associated neurological disorder (HAND) and ranges from asymptomatic condition to minor neurological features to severe dementia. Cerebrospinal fluid (CSF) analysis helps to rule out the presence of other opportunistic infections. Neuroimaging helps establish the diagnosis. We report a case of a 39-year-old African American female who presented with signs and symptoms suggestive of acute multiple sclerosis (MS) flares in the setting of advanced acute immunodeficiency syndrome (AIDS) encephalopathy. She presented with bilateral lower extremity muscle weakness and pain with apparent cognitive decline. Notable laboratory findings included leukopenia with normal neutrophils and positive serology for HIV-1. The MRI showed mild post-contrast enhancement suggestive of demyelinating disease, favoring MS over progressive multifocal leukoencephalopathy (PML). Cerebrospinal fluid analysis was significant for positive oligoclonal bands and negative serology. She was started on antiretroviral therapy (ART) for AIDS while holding steroids due to the possibility of worsening AIDS. After treatment for HIV, she showed immunologic and functional status improvement. HIV encephalopathy must be diagnosed by ruling out other similar presenting neurological illnesses for tactful patient management.

Nocardia beijingensis brain abscesses in an HIV-infected individual.

We describe a case of a 50-year-old Hispanic man diagnosed with HIV/AIDS who presented with a generalized tonic clonic seizure and ring enhancing cerebral lesions on imaging. He was initially treated for CNS toxoplasmosis but presented to the hospital with another tonic clonic seizure despite prescribed therapy. Brain biopsy was performed which revealed Nocardia beijingensis. He was treated with intravenous meropenem and trimethoprim/sulfamethoxazole for six weeks followed by long term oral trimethoprim/sulfamethoxazole with radiographic and clinical improvement.

Clinical outcomes of carbapenem-resistant Acinetobacter baumannii bloodstream infections: study of a 2-state monoclonal outbreak.

OBJECTIVE: To characterize the clinical outcomes of patients with bloodstream infection caused by carbapenem-resistant Acinetobacter baumannii during a 2-state monoclonal outbreak. DESIGN: Multicenter observational study. Setting. Four tertiary care hospitals and 1 long-term acute care hospital. METHODS: A retrospective medical chart review was conducted for all consecutive patients during the period January 1, 2005, through April 30, 2006, for whom 1 or more blood cultures yielded carbapenem-resistant A. baumannii. RESULTS: We identified 86 patients from the 16-month study period. Their mortality rate was 41%; of the 35 patients who died, one-third (13) had positive blood culture results for carbapenem-resistant A. baumannii at the time of death. Risk factors associated with mortality were intensive care unit stay, malignancy, and presence of fever and/or hypotension at the time blood sample for culture was obtained. Only 5 patients received adequate empirical antibiotic treatment, but the choice of treatment did not affect mortality. Fifty-seven patients (66.2%) had a single positive blood culture result for carbapenem-resistant A. baumannii; the only factor associated with a single positive blood culture result was the presence of decubitus ulcers. Interestingly, during the study period, a transition from single to multiple positive blood culture results was observed. Four patients, 3 of whom were in a burn intensive care unit, were bacteremic for more than 30 days (range, 36-86 days). CONCLUSIONS: To our knowledge, this is the first time a study has described 2 patterns of bloodstream infection with A. baumannii: single versus multiple positive blood culture results, as well as a subset of patients with prolonged bacteremia.

Antibiotic therapy for Klebsiella pneumoniae bacteremia: implications of production of extended-spectrum beta-lactamases.

The prevalence of extended-spectrum beta -lactamase (ESBL) production by Klebsiella pneumonia approaches 50% in some countries, with particularly high rates in eastern Europe and Latin America. No randomized trials have ever been performed on treatment of bacteremia due to ESBL-producing organisms; existing data comes only from retrospective, single-institution studies. In a prospective study of 455 consecutive episodes of Klebsiella pneumoniae bacteremia in 12 hospitals in 7 countries, 85 episodes were due to an ESBL-producing organism. Failure to use an antibiotic active against ESBL-producing K. pneumoniae was associated with extremely high mortality. Use of a carbapenem (primarily imipenem) was associated with a significantly lower 14-day mortality than was use of other antibiotics active in vitro. Multivariate analysis including other predictors of mortality showed that use of a carbapenem during the 5-day period after onset of bacteremia due to an ESBL-producing organism was independently associated with lower mortality. Antibiotic choice is particularly important in seriously ill patients with infections due to ESBL-producing K. pneumoniae.

International prospective study of Klebsiella pneumoniae bacteremia: implications of extended-spectrum beta-lactamase production in nosocomial Infections.

BACKGROUND: Commonly encountered nosocomially acquired gram-negative bacteria, especially Klebsiella pneumoniae, produce extended-spectrum beta-lactamases (ESBLs) as an antibiotic resistance mechanism. OBJECTIVE: To determine whether microbiology laboratories should report the presence of ESBLs and to establish the infection-control implications of ESBL-producing organisms. DESIGN: Prospective observational study. SETTING: 12 hospitals in South Africa, Taiwan, Australia, Argentina, the United States, Belgium, and Turkey. PATIENTS: 440 patients with 455 consecutive episodes of K. pneumoniae bacteremia between 1 January 1996 and 31 December 1997; of these, 253 episodes were nosocomially acquired. MEASUREMENTS: The K. pneumoniae isolates were examined for the presence of ESBLs. Pulsed-field gel electrophoresis was used to analyze the molecular epidemiology of nosocomial bacteremia with ESBL-producing K. pneumoniae. RESULTS: Overall, 30.8% (78 of 253) episodes of nosocomial bacteremia and 43.5% (30 of 69) episodes acquired in intensive care units were due to ESBL-producing organisms. After adjustment for potentially confounding variables, previous administration of beta-lactam antibiotics containing an oxyimino group (cefuroxime, cefotaxime, ceftriaxone, ceftazidime, or aztreonam) was associated with bacteremia due to ESBL-producing strains (risk ratio, 3.9 [95% CI, 1.1 to 13.8]). In 7 of 10 hospitals with more than 1 ESBL-producing isolate, multiple strains with the same genotypic pattern were observed, indicating patient-to-patient spread of the organism. CONCLUSIONS: Production of ESBLs by Klebsiella pneumoniae is a widespread nosocomial problem. Appropriate infection control and antibiotic management strategies are needed to stem the spread of this emerging form of resistance.

Community-acquired Klebsiella pneumoniae bacteremia: global differences in clinical patterns.

We initiated a worldwide collaborative study, including 455 episodes of bacteremia, to elucidate the clinical patterns of Klebsiella pneumoniae. Historically, community-acquired pneumonia has been consistently associated with K. pneumoniae. Only four cases of community-acquired bacteremic K. pneumoniae pneumonia were seen in the 2-year study period in the United States, Argentina, Europe, or Australia; none were in alcoholics. In contrast, 53 cases of bacteremic K. pneumoniae pneumonia were observed in South Africa and Taiwan, where an association with alcoholism persisted (p=0.007). Twenty-five cases of a distinctive syndrome consisting of K. pneumoniae bacteremia in conjunction with community-acquired liver abscess, meningitis, or endophthalmitis were observed. A distinctive form of K. pneumoniae infection, often causing liver abscess, was identified, almost exclusively in Taiwan.