Impact of highly active antiretroviral therapy (HAART) on the incidence of bacterial infections in HIV-infected subjects

Factors associated with urinary tract infections among HIV-1 infected patients

Background

Urinary tract infections remain an important yet underinvestigated clinical problem among HIV infected patients. Here we analyze factors associated with its occurrence and the spectrum of bacterial pathogens identified in the group of patients followed at the HIV Out-Patient Clinic in Warsaw.

Methods

Clinic database collected all medical information on patients routinely followed since 1994 to 2015. All patients with available urine culture were included into analyses, only the first culture was included. In statistical analyses logistic regression models were used to identify factors associated with positive culture.

Results

In total 608 patients had urine culture performed, 176 (28.9%) were females and 432 (71,1%) were males, 378 (62.2%) registered in care before/in 2007, 258 (42.4%) infected through homosexual contact. Median baseline lymphocyte CD4+ count was 385 (IQR:204–565) cells/μl and median nadir lymphocyte CD4+ count 197 (86–306) cells/μl. One hundred and eighteen patients were actively infected with HCV, as defined by positive real-time PCR. In total 141 (23.2%) patients had positive urine culture, the most common bacterial pathogen was E.coli (58.2%) and E. faecalis (12.8%). Patients with urinary tract infection were more likely to be female (51.8% vs. 22.1%, p<0.0001), infected through other than homosexual mode (80.1% vs. 50.7%, p<0.0001), with lower nadir CD4 count (139 vs. 221 cells/μl, p<0.0001) and lower baseline HIV RNA (4.02 vs. 4.35 log copies/ml, p = 0.01) and less likely to be HCV RNA positive (26.9% vs. 49.2%, p = 0.01). In multivariate regression model being registered before/in 2007 (OR = 2.10; [95%CI: 1.24–3.56]), infected through other than homosexual mode (2.05;[1.18–3.56]) and female gender (2.14;[1.33–3.44]) were increasing and higher nadir CD4+ count decreasing (0.92;[0.85–0.99]) the odds of urinary tract infection.

Conclusions

We have identified that almost one third of patients had urinary tract infections with non-typical bacterial pathogens. Population with increased odds of urinary tract infections are women, patients infected through other than homosexual contacts and those registered before 2007.

Urinary Tract Infection among Antiretroviral Therapy Users and Nonusers in Jimma University Specialized Hospital, Jimma, Ethiopia

Background. The introduction of antiretroviral therapy (ART) has dramatically reduced morbidity related with bacterial infection including urinary tract infection (UTI) among patients with HIV/AIDS. This study was carried out to determine the prevalence of UTI and identify common bacterial etiologies among HIV/AIDS patients of ART users and nonusers in Jimma University Specialized Hospital. Methods. A comparative cross sectional study was conducted from September to December 2012 on 367 ART users and 114 nonuser patients attending ART clinic. Sociodemographic characteristics, associated factors, and urine samples were collected; culture, biochemical tests, Gram stain, and drug sensitivity tests were done. Results. Of 467 examined urine samples, 56 (12%) had significant bacterial growth. Forty-six (12.5%) of the cases were ART users and 10 (10%) were nonusers. E. coli was the predominant isolate in both ART users (25 (54.3%)) and nonusers (6 (6%)). Majority of the bacterial isolates were from females. Most (>75%) of the isolates from both groups were resistant to ampicillin and trimethoprim-sulfamethoxazole but sensitive to norfloxacine, ceftriaxone, and chloramphenicol. Conclusion. There was no statistically significant difference regarding the prevalence of significant bacterial growth between ART users and nonusers. Therefore, it is recommended that UTI in both groups should be managed with drugs that show sensitivity.

Bacteremia as a cause of fever in ambulatory, HIV-infected Mozambican adults: results and policy implications from a prospective observational study

Fever is typically treated empirically in rural Mozambique. We examined the distribution and antimicrobial susceptibility patterns of bacterial pathogens isolated from blood-culture specimens, and clinical characteristics of ambulatory HIV-infected febrile patients with and without bacteremia. This analysis was nested within a larger prospective observational study to evaluate the performance of new Mozambican guidelines for fever and anemia in HIV-infected adults (clinical trial registration NCT01681914, www.clinicaltrials.gov); the guidelines were designed to be used by non-physician clinicians who attended ambulatory HIV-infected patients in very resource-constrained peripheral health units. In 2012 (April-September), we recruited 258 HIV-infected adults with documented fever or history of recent fever in three sites within Zambézia Province, Mozambique. Although febrile patients were routinely tested for malaria, blood culture capacity was unavailable in Zambézia prior to study initiation. We confirmed bacteremia in 39 (15.1%) of 258 patients. The predominant organisms were non-typhoid Salmonella, nearly all resistant to multiple first-line antibiotics (ampicillin, chloramphenicol, and trimethoprim-sulfamethoxazole). Features most associated with bacteremia included higher temperature, lower CD4+ T-lymphocyte count, lower hemoglobin, and headache. Introduction of blood cultures allowed us to: 1) confirm bacteremia in a substantial proportion of patients; 2) tailor specific antimicrobial therapy for confirmed bacteremia based on known susceptibilities; 3) make informed choices of presumptive antibiotics for patients with suspected bacteremia; and 4) construct a preliminary clinical profile to help clinicians determine who would most likely benefit from presumptive bacteremia treatment. Our findings demonstrate that in resource-limited settings, there is urgent need to expand local microbiologic capacity to better identify and treat cases of bacteremia in HIV-infected and other patients, and to support surveillance. Data on the prevalence and susceptibility patterns of important pathogens can guide national formulary and prescribing practices.

The immunology of Leishmania/HIV co-infection

Leishmaniases are emerging as an important disease in human immunodeficiency virus (HIV)-infected persons living in several sub-tropical and tropical regions around the world, including the Mediterranean. The HIV/AIDS pandemic is spreading at an alarming rate in Africa and the Indian subcontinent, areas with very high prevalence of leishmaniases. The spread of HIV into rural areas and the concomitant spread of leishmaniases to suburban/urban areas have helped maintain the occurrence of Leishmania/HIV co-infection in many parts of the world. The number of cases of Leishmania/HIV co-infection is expected to rise owing to the overlapping geographical distribution of the two infections. In Southwestern Europe, there is also an increasing incidence of Leishmania/HIV co-infection (particularly visceral leishmaniasis) in such countries as France, Italy, Spain and Portugal. Studies suggest that in humans, very complex mechanisms involving dysregulation of host immune responses contribute to Leishmania-mediated immune activation and pathogenesis of HIV. In addition, both HIV-1 and Leishmania infect and multiply within cells of myeloid or lymphoid origin, thereby presenting a perfect recipe for reciprocal modulation of Leishmania and HIV-1-related disease pathogenesis. Importantly, because recovery from leishmaniases is associated with long-term persistence of parasites at the primary infection sites and their draining lymph nodes, there is very real possibility that HIV-mediated immunosuppression (due to CD4(+) T cell depletion) could lead to reactivation of latent infections (reactivation leishmaniasis) in immunocompromised patients. Here, we present an overview of the immunopathogenesis of Leishmania/HIV co-infection and the implications of this interaction on Leishmania and HIV disease outcome.

Pulmonary infections in HIV-infected patients: an update in the 21st century

From the first descriptions of HIV/AIDS, the lung has been the site most frequently affected by the disease. Most patients develop a pulmonary complication during the history of HIV infection, mainly of infectious aetiology. Important changes in the epidemiology of HIV-related pulmonary infections have occurred. Overall, prescription of Pneumocystis jirovecii prophylaxis and the introduction of highly active antiretroviral therapy (HAART) are the main causes. Currently, the most frequent diagnosis in developed countries is bacterial pneumonia, especially pneumococcal pneumonia, the second most frequent cause is Pneumocystis pneumonia and the third is tuberculosis. However, in Africa, tuberculosis could be the most common pulmonary complication of HIV. Pulmonary infections remain one of the most important causes of morbidity and mortality in these patients, and the first cause of hospital admission in the HAART era. Achieving an aetiological diagnosis of pulmonary infection in these patients is important due to its prognostic consequences.

Bloodstream infections: evolution and trends in the microbiology workload, incidence, and etiology, 1985-2006

Information available on bloodstream infection (BSI) is usually restricted to short periods of time, certain clinical backgrounds, or specific pathogens, or is just outdated. We conducted the current prospective study of patients with BSI in a 1750-bed teaching hospital to evaluate workload trends and the incidence and etiology of BSI in a general hospital during the last 22 years, including the acquired immunodeficiency syndrome (AIDS) era. The main outcome measures were laboratory workload, trends in incidence per 1000 admissions and per 100,000 population of different microorganisms, and the impact of the human immunodeficiency virus (HIV) epidemic in the period 1985-2006.From 1985 to 2006 we had 27,419 episodes of significant BSI (22,626 patients). BSI incidence evolved from 16.0 episodes to 31.2/1000 admissions showing an annual increase of 0.83 episodes/1000 admissions (95% confidence interval, 0.61-1.05; p < 0.0001). The evolution of the incidence per 1000 admissions and per 100,000 population of different groups of microorganisms was as follows: Gram positives 8.2 to 15.7/1000 admissions and 66.8 to 138.3/100,000 population; Gram negatives 7.8 to 16.2/1000 admissions and 63.5 to 141.9/100,000 population; anaerobes 0.5 to 1.3/1000 admissions and 4.1 to 11.7/100,000 population; and fungi 0.2 to 1.5/1000 admissions and 1.7 to 12.5/100,000 population. All those differences were statistically significant. We observed the emergence of multiresistant Gram-positive and Gram-negative microorganisms. At least 2484 episodes of BSI (9.1%) occurred in 1822 patients infected with HIV. The incidence of BSI in HIV-infected patients increased from 1985 and reached a peak in 1995 (17.6% of BSI). Since 1995, the decrease was continuous, and in 2006 only 3.9% of all BSI episodes occurred in HIV-positive patients in our institution. We conclude that the BSI workload has increased in modern microbiology laboratories. Gram-positive pathogens have overtaken other etiologic agents of BSI. Our observation shows the remarkable escalation of some resistant pathogens, and the rise and relative fall of BSI in patients with HIV.

Incidence of, risk factors for, clinical presentation, and 1-year outcomes of infective endocarditis in an urban HIV cohort

BACKGROUND

Previous studies described infective endocarditis (IE) in the era before highly active antiretroviral therapy (HAART); however, IE has not been well studied in the current HAART era. We evaluated the incidence of, risk factors for, clinical presentation, and 1-year outcomes of IE in HIV-infected patients.

METHODS

We evaluated all cases of IE diagnosed between 1990 and 2002 in patients followed at the Johns Hopkins Hospital outpatient HIV clinic. To identify factors associated with IE in the current era of HAART, a nested case-control analysis was employed for all initial episodes of IE occurring between 1996 and 2002. Logistic regression analyses were used to assess risk factors for IE and factors associated with 1-year mortality.

RESULTS

IE incidence decreased from 20.5 to 6.6 per 1000 person-years (PY) between 1990 and 1995 and 1996 and 2002. The majority of IE cases were male (66%), African American (90%), and injection drug users (IDUs) (85%). In multivariate regression, an increased risk of IE occurred in IDUs (AOR, 8.71), those with CD4 counts <50 cells/mm, and those with HIV-1 RNA >100,000 copies/mL (AOR, 3.88). Common presenting symptoms included fever (62%), chills (31%), and shortness of breath (26%). The most common etiologic organism was Staphylococcus aureus (69%; of these 11 [28%] were methicillin resistant). Within 1 year, 16% had IE recurrence, and 52% died. Age over 40 years was associated with increased mortality.

CONCLUSIONS

IE rates have decreased in the current HAART era. IDUs and those with advanced immunosuppression are more likely to develop IE. In addition, there is significant morbidity and 1-year mortality in HIV-infected patients with IE, indicating the need for more aggressive follow-up, especially in those over 40 years of age. Future studies investigating the utility of IE prophylaxis in HIV patients with a history of IE may be warranted.

Impact of highly active antiretroviral therapy on organ-specific manifestations of HIV-1 infection

In the last 10 years, interesting results have been reported concerning the impact of highly active antiretroviral therapy (HAART) on the changing pattern of organ‐specific manifestations of HIV‐1 infection. There has been a clear step‐wise reduction in the incidence of several opportunistic infections (OIs), particularly Pneumocystis carinii pneumonia, whereas a nonsignificant reduction in incidence has been observed for other organ‐specific diseases, including invasive cervical cancer and Hodgkin disease. In addition, several organ‐specific manifestations, including HIV‐associated nephropathy, wasting syndrome and cardiomiopathy, are a direct consequence of damage by HIV‐1, and so HAART may have a therapeutic effect in improving or preventing these manifestations. Finally, the introduction of HAART has seen the emergence of several complications, termed immune reconstitution inflammatory syndrome, which includes OIs such as cytomegalovirus vitritis, Mycobacterium avium complex lymphadenitis, paradoxical responses to treatment for tuberculosis, and exacerbation of cryptococcosis. Because not all HIV‐1 organ‐specific manifestations are decreasing in the HAART era, this review will analyse the influence of HAART on several organ‐specific manifestations, and in particular OIs related to several organs, cerebral disorders and HIV‐1‐related neoplasia.

Pneumonia associated with HIV infection

PURPOSE OF REVIEW

Pneumonia occurs commonly in HIV-infected patients and this review highlights some of the recent findings in the epidemiology, pathogenesis, clinical features, treatment and prevention of this condition.

RECENT FINDINGS

Pneumonia remains an important cause of morbidity and mortality in HIV-infected patients. A number of factors have been identified that increase the risk of pneumonia. Cigarette smoking increases the risk of lung colonization, as well acute pneumonia due to Pneumocystis jiroveci, and has been documented to produce significant depression of the phagocytic function of alveolar macrophages in HIV-infected patients, which may underlie this risk. Legionella pneumophila infections appear to be uncommon in HIV-infected patients, while pneumonia with Streptococcus pneumoniae continues to occur with regularity, including infections with antibiotic-resistant isolates. Pneumocystis pneumonia occurs with a low incidence in patients receiving HAART, once the CD4 count increases to over 200 microl. Studies of invasive pneumococcal infections (predominantly pneumonia) indicate that in critically ill cases, including HIV-seropositive patients, combination antibiotic therapy is associated with a lower mortality than monotherapy. The 23-polyvalent pneumococcal vaccine has been shown to reduce the risk of pneumococcal infection in HIV-infected adults receiving HAART, and a 9-valent conjugate pneumococcal vaccine has been shown to reduce the incidence of radiologically confirmed pneumonia in HIV-seropositive and HIV-seronegative children.

SUMMARY

Pneumonia remains an important condition in HIV-infected patients, but recent studies demonstrate that antibiotic prophylaxis, the introduction of HAART, recognition of specific risk factors, new antibiotic treatment strategies and effective vaccines should serve to decrease its impact.

Community-acquired pneumonia in casualty

PURPOSE OF REVIEW

Community-acquired pneumonia, because of its substantial treatment costs, incidence, and mortality, is an aggressively researched diagnosis. In this review, we highlight new developments in the diagnosis, etiology, pathophysiology, treatment, and prevention of community-acquired pneumonia published since April 2002.

RECENT FINDINGS

The combined end points of improved patient care and conservation of health care resources have prompted several studies examining current professional society community-acquired pneumonia guidelines. In general, patients treated with the recommended third-generation cephalosporin and macrolide or an antipneumococcal fluoroquinolone when indicated have fared better, including reduced overall costs, inpatient days, and mortality, than those receiving alternative treatments. Etiologic identification efforts by traditional methods, blood and sputum cultures, are being questioned owing to poor success rates and, even when positive, are being underused or ignored in antibiotic selection and patient management. Newer diagnostic tests are becoming commercially available, along with tests for biologic markers that have been only recently identified as contributors to, or prognosticators of, community-acquired pneumonia. Because antibiotic resistance remains a major obstacle to successful patient treatment, prevention or mitigation of community-acquired pneumonia is gaining increasing popularity through more aggressive pneumococcal and influenza vaccination of at risk groups, even before hospital discharge from a community-acquired pneumonia admission.

SUMMARY

Although prevention is our best defense, current community-acquired pneumonia treatment guidelines are effective for treatment and cost containment. However, they should be scrutinized in light of clinical utilization data now entering the literature regarding their testing recommendations. Providers should consider encouraging focused culturing of sicker patients and those with significant comorbidities.