Hepatitis B vaccination in HIV-infected adults: current evidence, recommendations and practical considerations.

Immunization with hepatitis B (HBV) vaccine is recommended for all HIV-infected individuals without immunity to HBV. This patient population, however, has relatively poor HBV vaccine responses. Factors associated with this impaired HBV vaccine response in HIV-infected individuals may include older age, uncontrolled HIV replication, and low nadir CD4 cell count. Postvaccination testing for HBV surface antibody is recommended and vaccine non-responders should undergo repeat immunization with a full series. The benefit of double dosage, the appropriate strategy for HIV-infected patients with isolated HBV core antibody and the timing and number of vaccinations in persons with advanced immunosuppression on highly active antiretroviral therapy remain controversial areas.

Bartonellosis (Carrión's disease) in the modern era.

Bartonellosis remains a major problem in Peru, but many contemporary aspects of this disease have not been adequately described. We examined the cases of 145 symptomatic patients in Lima, Peru, in whom bartonellosis was diagnosed from 1969 through 1992, including 68 patients in the acute (hematic) phase and 77 patients in the eruptive (verruga) phase. In modern Peru, symptomatic patients who have acute-phase bartonellosis typically present with a febrile illness and systemic symptoms caused by profound anemia; most patients respond successfully to treatment with chloramphenicol. Patients who have eruptive-phase bartonellosis most often present with cutaneous verrugas but may have less specific symptoms, such as fever and arthralgias; diagnosis can be confirmed in such patients by Western immunoblotting, and most patients appear to respond to treatment with rifampin.

Retroviral rebound syndrome after cessation of suppressive antiretroviral therapy in three patients with chronic HIV infection.

BACKGROUND: Although viral rebound follows cessation of suppressive antiretroviral therapy in chronic HIV infection, a viremic clinical syndrome has not been described. OBJECTIVE: To describe a retroviral syndrome associated with cessation of effective antiretroviral therapy in chronic HIV infection. DESIGN: Case reports. SETTING: Outpatient HIV specialty clinics in Seattle, Washington, and Boston, Massachusetts. PATIENTS: Three patients with chronic HIV infection who discontinued suppressive antiretroviral therapy. MEASUREMENTS: Clinical course, plasma HIV RNA levels, and CD4 cell counts before, during, and after cessation of antiretroviral therapy. RESULTS: Within 6 weeks after stopping antiretroviral therapy, each patient experienced a clinical illness that resembled a primary HIV syndrome. This coincided with a marked increase in HIV RNA level and, in two of three patients, a decrease in CD4 cell count. After antiretroviral therapy was restarted, each patient's symptoms rapidly resolved in association with resuppression of HIV RNA and increase in CD4 cell count or percentage. CONCLUSION: A retroviral rebound syndrome similar to that seen in primary HIV syndrome can occur in patients with chronic HIV infection after cessation of suppressive antiretroviral therapy.

Bartonella quintana and urban trench fever.

Contemporary Bartonella quintana infections have emerged in diverse regions of the world, predominantly involving socially disadvantaged persons. Available data suggest that the human body louse Pediculus humanus is the vector for transmission of B. quintana. Descriptions of the clinical manifestations associated with contemporary B. quintana infections have varied considerably and include asymptomatic infection, a relapsing febrile illness, headache, leg pain, "culture-negative" endocarditis, and, in human immunodeficiency virus-infected persons, bacillary angiomatosis. Laboratory diagnosis is most convincing when B. quintana is isolated in blood culture, but growth often takes 20-40 days; problems exist with both sensitivity and specificity of serological assays. On the basis of available information, use of doxycycline, erythromycin, or azithromycin to treat B. quintana infections is recommended. Treatment of uncomplicated B. quintana bacteremia for 4-6 weeks and treatment of B. quintana endocarditis (in a person who does not undergo valve surgery) for 4-6 months are recommended, with the addition of a bactericidal agent (such as a third-generation cephalosporin or an aminoglycoside) during the initial 2-3 weeks of therapy for endocarditis.

Bacterial meningitis.

In recent years, investigators have made significant advances in understanding the pathogenesis of bacterial meningitis, particularly with regard to understanding the cascade of biologic events that cause excessive inflammation within the central nervous system (CNS). Nevertheless, the most important event in the field of bacterial meningitis in the past decade is the dramatic decline in the incidence of Haemophilus influenzae meningitis in children as a result of the widespread use of the conjugated H. influenzae type b vaccine. Currently, the most important clinical challenge in this field is the emergence of the drug-resistant Streptococcus pneumoniae. This problem has significantly complicated initial management of patients with suspected bacterial meningitis. Preliminary data show promise with new conjugated S. pneumoniae vaccines.

Resolution of recalcitrant hand warts in an HIV-infected patient treated with potent antiretroviral therapy.

Human papilloma virus (HPV)-related cutaneous manifestations occur with increased frequency and severity among HIV-infected persons. In this report, we describe an HIV-infected man with persistent, severe cutaneous hand warts that did not respond to multiple therapies, including liquid nitrogen cryotherapy, topical dinitrochlorobenzene, topical podophyllin, and intralesional interferon-alfa injections. Approximately 1 year after starting a potent protease inhibitor-containing antiretroviral regimen, the patient's recalcitrant cutaneous warts markedly diminished in size, even though the patient did not receive any specific therapy for the warts after starting aggressive antiretroviral therapy. The patient continued on a potent protease inhibitor-containing antiretroviral regimen and, approximately 2 years later, the warts completely resolved. Our patient's dramatic clinical improvement of cutaneous HPV infection that followed protease inhibitor-containing antiretroviral therapy provides a clear-cut example that protease inhibitor-containing combination antiretroviral therapy can produce significant clinical benefit.

Effect of trimethoprim-sulfamethoxazole as Pneumocystis carinii pneumonia prophylaxis on bacterial illness, Pneumocystis carinii pneumonia, and death in persons with AIDS.

To measure the effect of trimethoprim-sulfamethoxazole (TMP-SMX) in preventing bacterial illness, Pneumocystis carinii pneumonia (PCP), and death in people with AIDS, we conducted a retrospective medical record review of 1078 persons who were observed for 3 years on average who attended nine outpatient facilities in Seattle, Washington between January 1990 and April 1996. We calculated relative risk estimates to measure the protective effect of TMP-SMX on the development of major bacterial illnesses, PCP, and death. Use of TMP-SMX decreased the risk of PCP (relative risk [RR] = 0.23; 95% confidence interval [CI], 0.14-0.36) and deaths not attributable to PCP (RR = 0.59; 95% CI, 0.47-0.73). Prevention of major bacterial illnesses of known etiology was of borderline significance (RR = 0.77; 95% CI, 0.57-1.05) and became statistically significant with the addition of patients with infections of unknown etiology (RR = 0.77; 95% CI 0.61-0.97). Use of TMP-SMX PCP prophylaxis significantly reduced the risks of death and of PCP and was associated with a trend toward reduced risk of major bacterial infections.

Antibiotic resistance in community-acquired respiratory tract infections: current issues.

OBJECTIVE: In recent years, antibiotic resistance has emerged as an important global problem. The major goal of this review is to update important issues pertaining to antibiotic resistance, with an emphasis on antibiotic resistance involving community-acquired respiratory pathogens. In addition, this review examines potential reasons why antibiotic resistance has increased in recent years, how clinicians can better understand commonly used laboratory antibiotic resistance tests, and possible solutions to the increasing problem of antibiotic resistance. The article emphasizes the diagnosis, therapy, and prevention of antibiotic-resistant infections. DATA SOURCES: We identified relevant English-language articles through MEDLINE search (1966 to March 1998). All articles related to antibiotic resistance and the scope of the articles included original investigative articles, reviews, letters, and editorials. In addition, we selected additional references from the bibliographies of the identified articles. STUDY SELECTION: We selected articles for detailed review if they provided direct insight into the cause of antibiotic resistance, testing for antibiotic resistance, or the treatment of antibiotic resistance. Most, but not all, of the articles selected pertained to antibiotic resistance and respiratory tract infections. We performed a detailed review on approximately 40% of the originally selected articles. RESULTS: Multiple factors that play a significant role in the development of antibiotic resistance include the overuse of antibiotics in both humans and animals, situations such as day care that enhance transmission via frequent close personal contact, and widespread dissemination of resistant strains via global travel. Most respiratory pathogens have developed resistance to commonly used antibiotics either by producing beta-lactamase or by altering binding site proteins. CONCLUSIONS: In many regions of the United States, the level of antibiotic resistance has impacted the clinical management of common respiratory pathogens. Future efforts to curtail antibiotic resistance will require a concerted effort in multiple areas, particularly enhanced epidemiologic surveillance to better detect resistance trends, judicious use of antibiotics, and new drug development.

Bartonella-associated infections.

Bartonella-associated infections occur in immunocompetent and immunocompromised patients. The spectrum of diseases caused by Bartonella species has expanded and now includes cat-scratch disease, bacillary angiomatosis, bacillary peliosis, bacteremia, endocarditis, and trench fever. Most Bartonella-associated infections that occur in North America and Europe are caused by B. henselae or B. quintana. The domestic cat serves as the major reservoir for B. henselae; the reservoir for the modern day B. quintana infection remains unknown. Methods used to diagnose Bartonella-associated infections include histopathologic analysis of biopsy specimens, culture of tissue samples, blood culture, and serology. Available data on treatment of Bartonella-associated infections remain relatively sparse but would suggest that erythromycin or doxycycline provide the best responses.

Evaluation of an extended blood culture protocol to isolate fastidious organisms from patients with AIDS.

Recent reports of fastidious pathogens suggest the need for special blood cultures for immunocompromised patients. Blood cultures from 45 human immunodeficiency virus (HIV)-infected patients with unexplained fever (> or = 38.0 degrees C) and CD4 counts of < 125 cells per mm3 were collected into a vacuum tube with sodium polyanetholsulfonate, an Isolator tube, and BACTEC aerobic and anaerobic bottles. Blood from the sodium polyanethosulfonate tube was inoculated into BACTEC 13A bottles, which were read weekly for 16 weeks. Isolator sediment was divided among eight agar media, including four sheep blood agar media: chocolate agar, brain heart infusion blood agar, heart infusion blood agar, and brucella blood agar. Other agar plates included Sabouraud's, buffered charcoal-yeast extract, Middlebrook 7H11 (M7H11) with hemoglobin, and M7H11 with mycobactin J. Incubation conditions included air and CO2-enriched aerobic, microaerophilic, and anaerobic atmospheres. Aerobic BACTEC broths received an acridine orange stain on day 8 and were subcultured at 2, 4, and 8 weeks. Anaerobic BACTEC bottles were subcultured at 4 weeks. All solid media, including subcultures, were incubated for 8 weeks, providing a total of 16 weeks of incubation for each specimen. Clinically significant isolates included eight Mycobacterium avium complex isolates and one each of Bartonella henselae, Bartonella quintana, Shigella flexneri, Klebsiella oxytoca, and Cryptococcus neoformans. All isolates were detected with commercially available media and, with the exception of Bartonella spp., were recovered within incubation times routinely used in most clinical laboratories.

Seroprevalence to Bartonella quintana among patients at a community clinic in downtown Seattle.

In 1993, an outbreak of 10 cases of Bartonella quintana bacteremia occurred among homeless, alcoholic, human immunodeficiency virus (HIV)-negative persons in Seattle. To estimate the prevalence of past exposure B. quintana among this population, a serosurvey was conducted in 1994 among patients at a downtown Seattle clinic. Microimmunofluorescent titers to B. quintana in 192 clinic patients were compared with titers in 199 age- and sex-matched Seattle volunteer blood donors. Titers > or = 64 were detected in 20% (39/192) of clinic patients compared with 2% (4/199) of blood donors (P<.001). Among clinic patients, alcohol abuse was independently associated in multivariate analysis with titers > or = 64 (odds ratio, 3.3; 95% confidence interval, 1.6-6.9). Of the 39 patients with B. quintana titers > or = 64, 24 (62%) also had titers > or = 64 to Bartonella henselae, indicating serologic cross-reactivity between Bartonella species. These results suggest that a substantial proportion of this indigent, inner-city Seattle population was infected with B. quintana.

Lactobacillemia in three patients with AIDS.

Lactobacillemia, an uncommon cause of bacteremia, has been reported to occur in one renal transplantation patient who was also infected with human immunodeficiency virus (HIV). We present the cases of three patients with AIDS in whom lactobacillemia developed. All three patients had late-stage AIDS with CD4 cell counts of < 55/mm3, all had indwelling central venous catheters, and all were recently or concomitantly blood culture-positive for coagulase-negative staphylococci. In addition, two of the three patients had recently received vancomycin therapy. These three cases provide the first association of lactobacillus bacteremia and AIDS.

Clinical presentation of minimally invasive and in situ squamous cell carcinoma of the anus in homosexual men.

From January 1988 to December 1993, we identified six men with minimally invasive (stage I) squamous cell carcinoma of the anus and 10 men with anal carcinoma in situ (CIS). Of the six patients with invasive carcinoma, four were infected with human immunodeficiency virus (HIV), including one with AIDS. Of the 10 patients with CIS, eight were infected with HIV, including four with AIDS. Anal pain and bleeding were the most common symptoms of minimally invasive anal cancer and anal CIS. Anal irritation, burning, or pruritus occurred more frequently in patients with CIS, whereas anal ulcers, masses, or abscesses were more frequent in patients with minimally invasive cancer. Several patients with CIS had a discrete area of leukoplakia in the anal canal or a pigmented plaque of the anus and anal canal. These lesions were not observed in patients with minimally invasive anal cancer. The symptoms and signs of early-stage anal cancer in men at risk for developing HIV infection or men infected with HIV often resemble those of other common anorectal diseases in homosexual men. Anal cancer in HIV-infected men is not limited to those individuals with AIDS.

Bartonella (Rochalimaea) species as a cause of apparent "culture-negative" endocarditis.

Bartonella quintana (formerly Rochalimaea quintana) is a recently recognized cause of apparent "culture-negative" endocarditis. We describe a 39-year-old, homeless man who developed aortic valve endocarditis caused by B. quintana. He had a history of alcoholism and was seronegative for the human immunodeficiency virus. We established that B. quintana was the cause of the endocarditis on the basis of the isolation of B. quintana from blood cultures, the compatibility of histochemical stains of cardiac valve tissue, the reactivity of the polymerase chain reaction specific for B. quintana on cardiac valve tissue, and the failure to isolate an alternative causative organism despite extensive efforts. This is the second report of endocarditis caused by B. quintana and the fourth report of endocarditis caused by a Bartonella species. On the basis of the findings of this report and those of other recent reports, further study is warranted to determine the overall role of Bartonella species in apparent culture-negative endocarditis.

Bartonella (Rochalimaea) quintana bacteremia in inner-city patients with chronic alcoholism.

BACKGROUND: Bartonella (Rochalimaea) quintana is a fastidious gram-negative bacterium known to cause trench fever, cutaneous bacillary angiomatosis, and endocarditis. Between January and June 1993 in Seattle, we isolated B. quintana from 34 blood cultures obtained from 10 patients not known to be infected with the human immunodeficiency virus (HIV). METHODS: After identifying the isolates as B. quintana by direct immunofluorescence and DNA-hybridization studies, we determined strain hybridization with studies of restriction-fragment-length polymorphisms (RFLPs) of the intergenic spacer (noncoding) region of ribosomal DNA amplified by the polymerase chain reaction (PCR). To characterize the epidemiologic and clinical features of bartonella infections in these patients, we performed a retrospective case-control study using as controls 20 patients with blood cultures obtained at approximately the same time as those obtained from the index patients. RESULTS: B. quintana isolates from the 10 patients were indistinguishable by PCR-RFLP typing. All 10 patients had chronic alcoholism, and 8 were homeless (P = 0.001 for both comparisons with controls). The six patients who underwent HIV testing were seronegative. At the time of their initial presentation, seven patients had temperatures of at least 38.5 degrees C. Six patients had three or more blood cultures that were positive for B. quintana, and in four of these patients B. quintana was isolated from blood cultures obtained 10 or more days apart. Subacute endocarditis developed in two patients and required surgical removal of the infected aortic valve in one of them. Nine patients recovered; one died of sepsis from Streptococcus pneumoniae infection. CONCLUSIONS: B. quintana is a cause of fever, bacteremia, and endocarditis in HIV-seronegative, homeless, inner-city patients with chronic alcoholism.

Bacteremia caused by a novel Bordetella species, "B. hinzii".

Bordetella spp. cause respiratory tract diseases in warm-blooded animals. Only Bordetella bronchiseptica has been reported to cause bacteremia in humans, and this rare infection usually occurs with pneumonia in immunocompromised patients. We describe "Bordetella hinzii" bacteremia in an AIDS patient without a respiratory illness. Combining biochemical phenotyping with fatty acid analysis permitted preliminary identification of this previously undescribed pathogen; identity was confirmed by DNA-DNA hybridization. This report extends the spectrum of human infections caused by the bordetellae.