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Biomedical subjects

Pablo Rivas

Publications and source records attributed to Pablo Rivas.

17 recordsLinked to original sources
PubMed2007

Impact of syphilis infection on HIV viral load and CD4 cell counts in HIV-infected patients.

OBJECTIVES: To assess the effect of early syphilis on HIV viral load (VL) and CD4 cell count in patients with HIV and to analyze factors associated with changes in HIV VL and CD4 cell count. DESIGN: Multicenter study of a series of patients with HIV who were diagnosed with early syphilis infection during 2004 through 2005. Patients who started or changed their highly active antiretroviral therapy (HAART) regimen during the analysis period were excluded. RESULTS: One hundred eighteen patients were analyzed: 95.8% were men, mean patient age was 38.2 years, 83.9% were homosexual men, 50.8% were on antiretroviral therapy at the time syphilis was diagnosed, and HIV and syphilis diagnoses were coincident in 38 (32.2%) cases. CD4 cell counts were lower during syphilis than before (590 vs. 496 cells/microL; P = 0.0001) and after syphilis treatment (509 vs. 597 cells/microL; P = 0.0001). The HIV VL increased in 27.6% of patients during syphilis. The only factor associated with an HIV VL increase was not being on HAART, and the only factor associated with a CD4 count decrease >100 cells/microL during syphilis was the prior CD4 cell count. CONCLUSIONS: Syphilis infection was associated with a decrease in the CD4 cell count and an increase in the HIV VL in almost one third of the patients. In this series, more than two thirds of the syphilis cases were diagnosed in patients who were previously known to be infected with HIV.

Adult↗
PubMed2006

Predictors of liver fibrosis in HIV-infected patients with chronic hepatitis C virus (HCV) infection: assessment using transient elastometry and the role of HCV genotype 3.

BACKGROUND: Liver fibrosis is accelerated in patients coinfected with hepatitis C virus (HCV) and human immunodeficiency virus (HIV). The reasons for this faster liver disease progression are unclear, although higher plasma HCV RNA levels and distinct HCV genotype distribution in this population, compared with in HCV-monoinfected subjects, could play a role. METHODS: Liver fibrosis was assessed using elastometry in all consecutive HIV-infected patients with chronic hepatitis C who attended our institution (Hospital Carlos III, Madrid) during the past 12 months. Hepatic stiffness was measured in kiloPascal units (kPa) and was interpreted on the basis of Metavir score: no or mild fibrosis (score, F0-F1) when liver stiffness is < or =7.1 kPa, and fibrosis with septa or cirrhosis (F2-F4) when >7.1 kPa. RESULTS: A total of 283 patients (71% were male; mean age, 42 years; 94% were injection drug users and 94% were receiving antiretrovirals; mean CD4 cell count, 554 cells/microL; 72% with plasma HIV RNA level of <50 copies/mL) were analyzed. The mean alanine aminotransferase level was 68 IU/L, and the mean plasma HCV RNA level was 5.9 log IU/mL. HCV genotype distribution was as follows: genotype 1, 60% of patients; genotype 2, 2%; genotype 3, 26%; and genotype 4, 12%. Overall, 164 (58%) of the patients had scores indicating advanced liver fibrosis (F2-F4), as determined using elastometry. In the univariate and multivariate analyses, respectively, a significant odds ratio (OR) for score F2-F4 was found for HCV genotype 3, compared with the other genotypes (OR, 1.9 [95% confidence interval {CI}, 1.1-3.4] vs. 4.3 [95% CI, 1.4-13.3]); for older age (OR, 1.1 [95% CI, 1.03-1.17] vs. 1.1 [95% CI, 1.01-1.25]); and for elevated alanine aminotransferase levels (OR, 1.02 [95% CI, 1.01-1.03] vs. 1.03 [95% CI, 1.01-1.04]). Although patients with HCV genotype 1 had higher mean serum HCV RNA levels than did those with HCV genotype 3 (6.1 log IU/mL vs. 5.7 log IU/mL; P=.01), patients with HCV genotype 3 tended to have F2-F4 scores more frequently than did those with HCV genotype 1 (69% vs. 58%; P = not significant). CONCLUSIONS: HCV genotype 3, older age, and elevated alanine aminotransferase levels are independent predictors of advanced liver fibrosis in HCV-HIV-coinfected patients.

Adult↗
PubMed2006

Higher risk of hyperglycemia in HIV-infected patients treated with didanosine plus tenofovir.

The combination of didanosine (ddI) and tenofovir (TDF) has potential advantages, but because of several pitfalls (unexpected decreases in CD4+ T cells, increased risk of pancreatitis) its use has been questioned. Since anecdotal cases of transient insulin-dependent diabetes mellitus were seen in our clinic in patients on ddI + TDF-containing regimens, we explored the rate of this complication in more detail. Retrospective analysis of plasma glucose levels in patients who completed 12 months of treatment with three different triple antiretroviral regimens including ddI + TDF, TDF, or ddI was done. Patients taking antidiabetic drugs and/or those with baseline glucose levels >125 mg/dl were excluded. Weight, age, concomitant antiretrovirals, and ddI dose were assessed. At 12 months without treatment changes, fasting glucose levels were compared to baseline. A multivariate analysis was performed to evaluate which variables were associated with glucose elevations. A total of 177 HIV-infected patients were assessed (78 on ddI + TDF, 42 on TDF, and 57 on ddI). Mean baseline features were well balanced between groups for age (mean, 39 years), gender (78% male), CD4+ count (mean, 507 cells/mm3), weight (mean, 67 kg), and glucose level (mean, 95 mg/dl). There were only significant differences between groups for baseline viral load and protease inhibitor (PI) use (13% in the ddI + TDF arm vs. 7% and 9% in the TDF and ddI arms, respectively). At 12 months, 60% of the patients in the ddI + TDF arm were taking ddI 250 mg/day and the rest were on ddI 400 mg/day. At 12 months, hyperglycemia was significantly more frequent in the ddI + TDF arm (33%) when compared to patients on TDF or ddI separately (5% and 10%, respectively). In the multiple linear regression analysis, a lower weight (beta -0.35; 95% CI -0.67 to -0.03; p = 0.033) and use of ddI + TDF (beta: 13.05; 95% CI: 0.2 to 26; p = 0.047) were independently associated with a higher risk of developing hyperglycemia. The risk of hyperglycemia is increased in patients treated with ddI + TDF, particularly in those with lower weight. As high ddI exposure has been associated with endocrine pancreatic dysfunction and diabetes, ddI "overdosing" as result of concomitant TDF use and low weight might explain our findings. These results add a further note of caution to the use of TDF and ddI in combination.

Adenine↗
PubMed2006

Severe liver disease associated with prolonged exposure to antiretroviral drugs.

BACKGROUND: Liver damage is frequently seen in HIV-positive subjects, often resulting from coinfection with hepatitis B and/or C viruses (HCV), alcohol abuse, etc. However, the etiology of liver disease still remains unknown for a small subset of individuals. METHODS: Cryptogenic liver disease (CLD) was defined as persistently elevated aminotransferases levels in the absence of hepatitis C and/or B viruses replication and of other common causes of liver disease (alcohol, medications, etc). We identified cases initially meeting this definition by examining all HIV-positive subjects attended during the year 2004 in 2 large HIV clinics in Spain. Their clinical charts were retrospectively reviewed, and their assessment completed when needed to rule out other less frequent causes of liver disease. The stage of liver fibrosis was assessed by liver biopsy and/or elastography. To assess which factors could be associated with CLD, HIV-positive controls were chosen and matched by age, gender, and CD4 status. RESULTS: CLD was diagnosed in 17 (0.5%) out of 3200 HIV-positive patients. Their mean age was 43 years, 82.4% were male, and 76% had acquired HIV through homosexual relationships. The mean time from HIV diagnosis was >15 years, and all patients had been exposed to antiretroviral therapy. Nevirapine, stavudine, and didanosine were the drugs more frequently used by this subset of patients. None of them had liver function test abnormalities before initiating antiretroviral therapy. Advanced liver fibrosis (F3-F4 Metavir scores) was recognized in 10 (58.8%) individuals, and 9 (52.9%) had developed symptomatic liver complications, including ascites (8), portal thrombosis (6), variceal bleeding (5), and encephalopathy (2). In the case-control analysis, prolonged didanosine exposure was the only independent predictor of developing CLD in this population. CONCLUSIONS: CLD is an uncommon condition in HIV-positive individuals and might be associated with prolonged didanosine exposure. It may evolve causing severe liver complications, with variceal bleeding and portal thrombosis being particularly frequent.

Adult↗
PubMed2005

Long-term follow-up of asymptomatic HIV-infected patients who discontinued antiretroviral therapy.

BACKGROUND: Whether asymptomatic human immunodeficiency virus (HIV)-infected patients can interrupt treatment remains unknown. METHODS: We performed a prospective, observational study of 46 patients who started therapy with >300 CD4+ cells/mm3 and/or <70,0000 HIV-1 RNA copies/mL. Patients had been receiving highly active antiretroviral therapy (HAART) for at least 6 months. HAART was discontinued, and plasma HIV-1 RNA loads and CD4+ cell counts were determined at 4-month intervals. RESULTS: At the time of HAART discontinuation, the median CD4+ cell count was 793 cells/mm3, and all patients had undetectable viral loads. A rapid decrease of 173 cells/mm3 in the median CD4+ cell count was observed during the first 4 months after HAART was stopped, followed by a slower decrease of 234 cells/mm3 between months 5 and 20. The decrease in the median CD4+ cell count early after HAART discontinuation was inversely correlated with the increase that occurred during receipt of therapy (r=-0.653) and with the count at the time of HAART discontinuation (r=-0.589). The decrease in the median CD4+ cell count after the fourth month without HAART was correlated with the nadir count before HAART initiation (r=-0.349) and the increase during treatment (r=-0.322). The median follow-up duration was 20 months. After 12, 24, and 36 months of observation, 33 patients (71.7%), 22 patients (47.8%), and 16 patients (34.7%), respectively, remained free of therapy. Adverse clinical events were not seen, and all patients who reinitiated HAART responded rapidly. CONCLUSION: Selected asymptomatic HIV-infected patients can safely discontinue therapy for prolonged periods of time.

Adult↗
PubMed2005

Sternal tuberculosis after open heart surgery.

We present a 68-y-old female who had undergone aortocoronary bypass and developed Staphylococcus aureus sternal osteomyelitis. Despite prolonged therapy with different antibiotics and several local debridements and drainage, the wound remained open and suppurative. Only after sternectomy and wide excision of infected costal cartilage was the diagnosis of sternal tuberculosis made, 24 months later. This case illustrates the necessity of a high degree of suspicion to diagnose this very rare entity which coexists with more common causes of sternal osteomyelitis.

Aged↗
PubMed2005

Cryptococcal meningitis in a patient with X-linked hyper-IgM1 syndrome.

A case is reported of cryptococcal meningitis in a 27-y-old male suffering from X-linked hyper-IgM1 syndrome. This congenital disorder is characterized by multiple infections of the respiratory and gastrointestinal tracts, but also opportunistic infections commonly seen in patients with cell-mediated immunity. His clinical recovery was good but the need for life-long secondary chemoprophylaxis to prevent relapses is unknown.

Adult↗
PubMed2005

The impact of hospital-acquired infections on the microbial etiology and prognosis of late-onset prosthetic valve endocarditis.

STUDY OBJECTIVES: To study the changing etiology of prosthetic valve endocarditis (PVE) and the impact of nosocomial acquisition of the infection on prognosis in a single hospital. METHODS: Retrospective review of 121 cases of PVE during a period of 34 years. Two different periods (the period from 1970 to 1986 [P1], and the period from 1987 to 2003 [P2]) were analyzed. RESULTS: During P1, 58 patients with PVE were treated (30 early PVE and 28 late PVE); during P2, 63 patients with PVE were treated (13 early PVE and 50 late PVE). The frequency of early-onset PVE decreased from 0.94% in P1 to 0.34% in P2 (p < 0.001), but the incidence rate of late-onset PVE did not change (0.33% and 0.42% per year, respectively). The microbiology of early PVE changed over the years: Gram-negative bacilli decreased from 40% during P1 to 7.7% in P2 (p = 0.033). Staphylococci remained the main causes of early PVE in both periods. The microbial etiology of late PVE also changed over the years with enterococci and Staphylococcus aureus as the leading causes during P2. Streptococcus viridans decreased from a leading position to a fourth position. Methicillin-resistant S aureus endocarditis appeared first in 1992. Eleven cases of late-onset PVE in P2 were hospital acquired (22%). In comparison, only two cases (7.1%) of hospital-acquired, late-onset PVE were seen in P1 (p = 0.11). Mortality of early-onset PVE decreased from 80% in P1 to 46% in P2 (p = 0.026). The overall mortality of late-onset PVE did not change between periods: 39% vs 34%. Mortality associated with nosocomial PVE in P2 was 63.6% (7 of 11 patients). In comparison, the mortality of community-acquired cases was 25.6% (10 of 39 patients; p = 0.03). In the multivariate analysis, the presence of comorbidities and hospital acquisition were associated with an excess of mortality (odds ratio [OR], 13.9; 95% confidence interval [CI], 1.23 to 158 [p = 0.033]; and OR, 10.8; 95% CI, 2.16 to 54.7 [p = 0.0037], respectively). CONCLUSION: Although the mortality associated with early-onset PVE has significantly decreased, in this series the mortality of patients with late-onset PVE remained high due mainly to an increasing number of patients with comorbidities who acquired the infection during admission for other diseases.

Adult↗
PubMed2005

Nucleoside/nucleotide backbones for the treatment of HIV infection.

Nucleoside/nucleotide analogs (NAs) are essential components of most current antiretroviral regimens. Although many dual NA combinations may be used as backbones, not all display optimal results. For instance, some associations should be avoided due to antagonism (eg, zidovudine plus stavudine), high rates of toxicity (eg, didanosine plus stavudine) and/or increased risk of virological failure (eg, didanosine plus tenofovir). Moreover, the knowledge of plasma and intracellular interactions between different NAs is important for choosing appropriate combinations and optimal doses in order to optimize antiviral efficacy and minimize toxicities.

Animals↗
PubMed2004

Long-term efficacy and safety of protease inhibitor switching to nevirapine in HIV-infected patients with undetectable virus load.

BACKGROUND: Simplified highly active antiretroviral therapy (HAART) regimens are becoming widely used, particularly as a result of the side effects of and difficult compliance with protease inhibitor (PI) therapy. However, the long-term efficacy of HAART has not been properly assessed. METHODS: We performed a prospective study of 110 patients infected with human immunodeficiency virus type 1 (HIV-1) with undetectable virus load who discontinued PI therapy and initiated therapy with nevirapine without changing nucleoside analogues. Reasons for switching were treatment simplification (45%), lipodystrophy (24%), renal problems (23%), and dyslipidemia (8%). HIV-1 load, CD4 cell count, and fasting biochemistry profiles were performed at the time of switching (baseline) and every 3-4 months thereafter. The aim of the study was to evaluate the long-term efficacy and safety of this combination. RESULTS: Sixty-eight patients (61.8%) had a duration of follow-up of 3 years. The mean increase in the CD4 cell count after 3 years was 90 cells/microL (13.8% from baseline). Virus loads remained undetectable in all patients but 9 (8.2%). Triglyceride levels dramatically improved at 12 months (a 75% decrease; P<.02) and remained statistically significant over time (P<.04). The same occurred with serum cholesterol levels: there was an initial reduction of 25% (P<.02) and at the end of the follow-up period (P<.015). However, at the long-term evaluation, complete normalization of mean serum cholesterol and triglyceride levels could not be achieved. Sixteen patients (14.5%) had to stop therapy as a result of nevirapine-associated side effects. CONCLUSIONS: The switching of a PI to nevirapine is a safe and well-tolerated option for maintaining long-term virological suppression and immunological control. Three years after starting nevirapine therapy, rates of hypercholesterolemia and hypertriglyceridemia improved, although normal cholesterol and triglyceride values were not achieved.

Adult↗
PubMed2004

Visceral leishmaniasis in immunocompromised patients with and without AIDS: a comparison of clinical features and prognosis.

Visceral leishmaniasis is basically a disease of healthy infants and adults. However, in the last decade an increasing number of cases of kala azar in immunocompromised patients have been reported with emphasis on atypical manifestations of the disease. During a period of 11 years, 20 immunocompromised patients with AIDS (12 patient), haematological neoplasia (3 patients), corticosteroid therapy (3 patients) or renal transplantation (2 patients) were studied by one or more of the authors. We did not find differences in the presentation of leishmaniasis between patient with or without AIDS and most patients had fever, enlargement of the liver and spleen, blood cytopenias and biochemical abnormalities. Serology was more frequently positive in HIV-negative than in HIV-positive patients (100% versus 63.6%; P=0.13). Bone marrow biopsy was diagnostic in 66% and 87% of patients with and without AIDS, respectively. Failure of anti-leishmanial therapy occurred in 6 of 19 patients treated (31.5%), and 3 patients with AIDS and another 3 without AIDS died during the first episode of leishmaniasis. Of 12 survivors, relapses occurred in five (41.6%). Only patients in whom immunosuppression was ameliorated by means of antiretroviral therapy or by reduction of corticosteroid and other immunosuppressive drugs did not relapse. Treatment of kala azar in immunocompromised host is in satisfactory and new drugs or strategies are urgently needed.

Adolescent↗
PubMed2004

Prosthetic valve endocarditis due to Listeria monocytogenes. Report of two cases and reviews.

INTRODUCTION: Endocarditis due to Listeria monocytogenes is a rare but serious disease often leading to valve dysfunction and heart failure. Two cases of listerial prosthetic valve endocarditis are reviewed along with 66 cases previously reported. RESULTS: The mean age of patients with listerial endocarditis increased from 47.1 years in the decades from 1955-1984 to 65.5 years from 1985-2000. Chronic debilitating diseases, solid tumours and immunosuppression associated with organ transplantation, hematologic neoplasia or AIDS were found in 41.1% of cases. Listerial endocarditis was a vegetative and destructive process, with dehiscense of the prosthesis and occasionally, abscess formation, fistulization and pericarditis. Treatment with penicillin or ampicillin alone or combined with gentamicin was adequate therapy in most cases. Vancomycin together with gentamicin may be a reasonable alternative therapy. CONCLUSIONS: Despite problems associated with microbial persistence and relapses in other forms of human listeriosis, antimicrobial therapy alone may be a successful treatment for listerial endocarditis, including cases occurring on prosthetic valves. Valve replacement may be reserved for complicated cases with valve dehiscense, cardiac failure or myocardial abscess. Overall mortality was 35.3%, although most patients who died did so before 1985 and since then mortality has been significantly reduced to 12%.

Aged↗
PubMedDate not supplied

Liver fibrosis in HIV-infected patients with chronic hepatitis B extensively exposed to antiretroviral therapy with anti-HBV activity.

PURPOSE: The extent and predictors of liver fibrosis were examined in a HIV/HBVcoinfected cohort with extensive exposure to anti-HBV active HAART. METHOD: Liver fibrosis was measured using transient elastography. RESULTS: Thirty-seven patients of a median age of 43 were included in the study. All but 2 patients had received anti-HBV drugs for a median time of 40 months in the context of HAART. F0-F1 METAVIR fibrosis scores (minimal or no fibrosis) as measured by elastography were found in 21 (57%) patients. AST levels were significantly lower among F0-F1 patients (33 IU/L) compared to F2-F4 patients (48 IU/L) (p = .01). ALT levels were also lower in F0-F1 patients (38 IU/L) than in F2-F4 patients (54 IU/L) (p = .05). CONCLUSION: In this HIV/HBV-coinfected cohort, with extensive HAART exposure including anti-HBV agents, more than half of the patients had no or minimal liver fibrosis. Higher transaminase levels were recognized in patients with higher degree of fibrosis.

Adult↗
PubMedDate not supplied

Efficacy of antiretroviral therapy in individuals infected with HIV-1 non-B subtypes.

The impact of HIV-1 subtype on clinical outcome following exposure to antiretroviral therapy is currently not well known. Natural polymorphisms are often present in HIV-1 non-B subtypes at positions known to be associated with drug resistance in clade B viruses. These changes might influence the emergence of drug-resistant viruses, modifying drug susceptibility and/or the virus replicative capacity. Moreover, different pathways may lead to drug resistance according to HIV-1 clade. Finally, the influence of subtype on the performance of phenotypic assays and in the interpretation of algorithms for genotypic resistance is currently a matter of debate. All these aspects explain why the response to antiretroviral therapy might vary in subjects infected with different HIV-1 clades.

Anti-HIV Agents↗