Ben J. Barnett

Urinary tract infection: an overview.

Urinary tract infection (UTI) remains very common. As many as 50% of women report having had at least one UTI in their lifetimes. Urinary tract infection is the most common cause of infection in nursing home residents and the most common source of bacteremia in the elderly population. Urinary tract infection occurs in patients with structurally or functionally abnormal urinary tracts (complicated UTI) and in patients with anatomically normal urinary tracts (uncomplicated UTI). Escherichia coli (E coli) is the most common cause of uncomplicated UTI, whereas antibiotic-resistant Enterobacteriaceae, enterococci, and Candida species often are the causes of complicated UTI. In this article we review current concepts of the epidemiology, microbiology, pathophysiology, clinical manifestations, diagnosis, and treatment of urinary tract infection.

Bloodstream Infection Associated with Needleless Device Use and the Importance of Infection-Control Practices in the Home Health Care Setting

The influence of infection-control practices on bloodstream infection (BSI) risk was examined in a home health care setting in which three needleless devices were used consecutively. A case-control study and a retrospective cohort study were conducted. Risk factors for BSI included lower education level, younger age, having a central venous catheter (CVC) with multiple ports, or having a tunneled CVC. Among patients with a tunneled CVC, those at greatest risk had been allowed to shower rather than bathe and to get their exit site wet (P<.01). A high proportion (49%) of isolates were hydrophilic gram-negative bacteria, suggesting water sources of infection. In the cohort study, the BSI rate decreased as the frequency of changing the needleless device end cap increased from once weekly up to every 2 days, suggesting that the mechanism for BSI may involve contamination from the end cap. These findings may help to develop infection-control measures specific to home health care.

Tongue Hyperpigmentation in a Caucasian Patient Coinfected With HIV and Hepatitis C During Peginterferon Alfa-2b and Ribavirin Therapy

Tongue Hyperpigmentation in a Caucasian Patient Coinfected With HIV and Hepatitis C During Peginterferon Alfa-2b and Ribavirin Therapy

Tuberculosis outbreak in a Texas prison, 1994

In 1994 a Texas prison containing a population of mentally retarded inmates experienced a large tuberculosis outbreak. Fifteen cases of tuberculosis were identified (8 confirmed by positive cultures for Mycobacterium tuberculosis) and more than 100 inmates became infected. The culture-confirmed patients were infected with an identical strain of tuberculosis as demonstrated by polymerase chain reaction (PCR) based DNA fingerprinting technique. The prison followed standard tuberculosis infection control policies, but these controls were inadequate to prevent tuberculosis transmission in this special population. Two hundred and thirty inmates (119 inmates showing evidence of new tuberculosis infection or active disease and 111 healthy controls) were enrolled in the investigation. Inmate cell assignments, job duties, and educational classes were identified and medical chart reviews were conducted on all inmates. Tuberculosis transmission was associated with residing on the D Wing of the prison (OR = 25.84, P < 0.01), attending school in Classroom A (OR = 8.34, P = 0.01) and working on the prison utility work crew (OR = 2.52, P < 0.01). The index case in the outbreak had been prescribed 6 months of isoniazid (INH) chemoprophylaxis in 1988.

Solitary Parietal Lobe Histoplasmoma Mimicking a Brain Tumor

We describe a rare case of Histoplasma infection, which manifested only as a brain histoplasmoma, in a previously healthy woman who had no underlying predisposing conditions. Only a few cases of such intracranial histoplasmomas have been reported but this entity can mimic a brain neoplasm and should be a diagnostic consideration during the evaluation of ring-enhancing brain lesions.

Hepatitis C virus genotype distribution varies by underlying disease status among patients in the same geographic region: A retrospective multicenter study

BACKGROUND Hepatitis C virus (HCV) is a known carcinogen with considerable genetic heterogeneity: six different genotypes have been identified. HCV genotype distribution varies from country to country. In the United States, the most prevalent genotypes are 1a, and 1b followed by genotypes 2, and 3. OBJECTIVES To examine whether the distribution of HCV genotypes differed by cancer status among patients in the same area. STUDY DESIGN We reviewed epidemiologic and virological data of 636 patients with HCV infection evaluated at 3 institutions in Houston, Texas, in 2008 and 2009. RESULTS We included 129 cancer patients (53 with hematologic malignancies and 76 with solid tumors), 333 immunocompetent patients, and 102 HIV-co-infected patients. The prevalence of genotype 1 (G-1) was 66% among cancer patients, 84% among immunocompetents (P=0.00004), and 99% among HIV-co-infected patients (P<0.00001). G-2 and G-3 were more common in cancer patients than other patients. Demographics, risk factors, and duration of HCV infection were similar between cancer and immunocompetent patients. G-1 was more prevalent in immunocompetents (84%) than in patients with hepatocellular carcinoma (74%, P=0.08) or lymphoma (59%, P=0.001). G-2 was more prevalent in lymphoma patients (24%) than in immunocompetents (8%, P=0.003); cancer risk was 3 times as great with G-2 as with other genotypes (OR 3.72, 95% CI 1.38-9.76). CONCLUSIONS This multicenter retrospective study provides evidence of differences in HCV genotype distribution by underlying disease among geographically related patients and suggests a possible greater carcinogenic potential of some variants. Large-scale prospective studies are warranted to investigate HCV genotype distribution in other regions.

Purification of ribonuclease T1

An improved method for purifying ribonuclease T1 from Aspergillus oryzae is described. The method uses gradient elution from DEAE-cellulose and sulfopropyl-Sephadex columns followed by gel filtration on Sephadex G-50 to give almost 100 mg (50% yield) of ribonuclease T1 from 100 g of starting material in less than 5 days.

Analysis of Sequence Configurations of the PKR-Interacting HCV Proteins from Plasma and PBMC as Predictors of Response to Interferon-Alpha and Ribavirin Therapy in HIV-Coinfected Patients

HIV/HCV-coinfected patients. A comprehensive understanding of IFN treatment response or failure is still lacking. However, it is well recognized that both HCV genotype and HCV RNA levels are major determinants for response to IFN therapy in HCV-monoinfected patients. The rate of response according to viral genotype could imply a differential role for those proteins with capability to affect the success of IFN-based therapy. The peripheral blood mononuclear cells (PBMCs) of a significant proportion of HCV-monoinfected subjects harbor viral variants ascribed to genotypes that are not found in plasma, likely acquired through superinfections [3] . The prevalence and the mechanisms of this compartmentalization, and their implications for anti-HCV therapy in HIV-coinfected patients are unknown. In order to study HCV-related genomic factors associated with the response to IFN therapy in patients coinfected with HIV, we analyzed the sequence configurations in the PKR-interacting viral proteins (NS5A and E2) of HCV and linked them with virological response in order to explore their value in predicting therapeutic response. Considering that HCV comTo the Editor Interferon (IFN) and ribavirin combination therapy for chronic hepatitis C virus (HCV) infection yields a sustained response rate of only 40%. Previous studies have linked IFN responsiveness to viral sequence variation in parts of the structural envelope 2 (E2) and NS5A genes. It has been proposed that mutations in the RNA-dependent protein kinase (PKR)binding domain (PKR-BD) within the HCV viral NS5A gene disrupt NS5A-PKR interactions and are important factors contributing to IFN sensitivity and repression of viral function. The proposed double-stranded RNA-dependent PKR-BD (codons 2209–2274) within the NS5A gene contains the putative IFN-sensitive determining region (ISDR, codons 2209–2248) which represses its function [1] . Similarly, the double-stranded RNA-activated protein kinase-eukaryotic initiation factor 2 alpha (PKR-eIF2) phosphorylation homology domain (PePHD, codons 659–670) within the E2 gene has been shown to interact with the IFN-induced PKR as a pseudosubstrate, interfering with its inhibitory effect on protein synthesis [2] . The role of these sequence variations is still controversial in HCV-monoinfected patients, and no data have been reported in Received: April 8, 2008 Accepted: July 27, 2008 Published online: September 30, 2008

Native Valve Endocarditis Due to Bartonella henselae in a Middle-Aged Human Immunodeficiency Virus-Negative Woman

ABSTRACT We report the case of a human immunodeficiency virus-negative woman who developed native valve endocarditis of the aortic valve due toBartonell henselae infection. The diagnosis was established using serology and PCR analysis of excised aortic valve tissue.

Experience of Corporate Medical Assistance Clinics during the Centennial Olympic Games, Atlanta, 1996

The health of travelers returning home from developing countries has received increased attention in recent years. Much of this attention has centered on immunizations, malaria chemoprophylaxis and treatment of travelers diarrhea. In contrast, there are very few data on the health problems of international travelers to developed countries such as the United States. We studied the experience of two corporate medical assistance clinics established for both national and international travelers to Atlanta, Georgia during the Centennial Summer Olympic Games in 1996.