[Vancomycin and teicoplanin use as antibiotic prophylaxis in cardiac surgery: pharmacoeconomic study]

BACKGROUND

To assess the economical impact of vancomycin use versus teicoplanin use as antibiotic prophylaxis for patients undergoing cardiac surgery for valve replacement (VR) and coronary artery by-pass (CABS) procedures.

PATIENTS AND METHODS

This is an ancillary cost minimization analysis of a double blinded, parallel groups, randomised clinical trial (RCT), with the main objective of comparing the safety and efficacy of these antibiotics. 500 patients were included in the study; 267 in the CABS group and 233 in the VR group. The CABS patients received 1 g vancomicin or 400 mg teicoplanin, plus 150 mg netilmicin. The VR group received a second dose of each drug after extracorporeal circulation. In order to calculate the costs we considered the direct cost of the drug, the i.v. mix and the administration costs, together with personnel and structure costs. We considered two different situations: the administration of drugs within the surgical room theatre and in the medical ward.

RESULTS

The demographic data of both groups were comparable. The frequency of severe adverse drug reactions (ADR) were similar (0.4%) in both groups, as well as the post-operative infection rates (8.6%). Differences were seen in the frequencies of low severity ADRs: 20.4% in the vancomycin group and 1.6% in the teicoplanin group. When the antibiotics were administered in the surgical room, among CABS patients the costs were 8,265 pts. for the teicoplanin group and 12,005 pts. for the vancomycin group; while among VR patients, costs were respectively 11,661 pts. and 14,528 pts. Administration costs of teicoplanin and vancomycin within a medical ward setting, however, the costs were 6,740 pts. and 2,809 pts. for CABS patients, and 5,308 pts. and 10,140 pts. for VR patients, respectively.

CONCLUSIONS

The costs of antibiotic prophylaxis among cardiac surgery patients heavily depends on the setting and circumstances of drug administration. The minimization cost analysis indicates that teicoplanin is the most cost-effective option if the drug is administered within the surgical area, while vancomycin is the less costly option when administered within the medical ward. However, if the second option is to be chosen, it is necessary to assure the right plasmatic drug levels of the antibiotic at the beginning of the surgical procedure.

[Recommendations of GESIDA (Grupo de Estudio de SIDA)/National Plan on AIDS with respect to the anti-retroviral treatment in adult patients infected with the human immunodeficiency virus in the year 2000 (II)]

OBJECTIVE

To update the recommendations for antiretroviral therapy (ART) in adult HIV-infected persons according to the new scientific advances and the existence of new antiretroviral drugs in the last two years.

METHODS

The ART recommendations have been condensed by a panel of experts from the Spanish AIDS Study Group (Grupo de Estudio de Sida-GESIDA) of the Spanish Infectious Diseases and Clinical Microbiology Society (SEIMC) and from the Clinical Advisory Panel (CAP) of the Secretariat of the Spanish National Plan on AIDS (SPNS) of the Ministry of Health. Three levels of evidence have been established depending if the data came from randomized and controlled studies, from cohort or case-control studies or from descriptive studies and expert opinions, for that purpose we have reviewed the advanced in HIV pathophysiology and results of efficacy (clinical, virologic and immunologic) and security (toxicity) from clinical trials involving ART lasting at least 12 months, from cohort studies and pharmacokinetic and security data of antoiretrovírico drugs, presented in international conferences or published in biomedical journals in the last two years. In each situation we have established either to recommend or to consider or not recommend ART.

RESULTS

Nowadays, ART consistent of at least three drugs constitutes the election therapy for chronic HIV infection, since it delays clinical progression, increases significantly the survival and diminishes hospital admissions and associated costs. The decision to start ART must be based upon three elements: presence or absence of symptoms, plasma vírica load and CD4+ cells counts. Thus, in asymptomatic cases with a high CD4+ cells count (> 500/microliter) and low vírica load (< 10,000 copies/ml by branched DNA bDNA or < 20,000 copies/ml by reverse-transcription polymerase chain reaction [RT-PCR] or nucleic acid sequence based amplification [NASBA]) we recommend to delay ART. In symptomatic patients we recommend to start it, and in asymptomatic patients, we could recommend or consider ART initiation depending on the risk of progression, established by the vírica load and the CD4+ cells count. In any case, if therapy is started, the objective must be to reach an indetectable vírica load (< 50 copies/ml). The adherence to ART plays a key role for its initial moment and for the duration of the antiviral response. ART can achieve a restoration of cellular immunity inb the advanced patients. There are few therapeutic options in failing patients due to cross-resistance. Resistance studies can be useful in this setting. The toxicity (lypodistrophy) is a new and limiting factor of ART which requires to look for new therapeutic options. ART criteria for acute infection, pregnancy, post-exposure prophylaxis and when to use resistance testing are discussed.

CONCLUSIONS

In this moment, there is a more conservative attitude towards starting ART than in previous recommendations in which a virus eradication was considered. On the other hand, the high number of disposable drugs, the more sensitive monitorization methods (plasma vírica load) and the possibility of performing resistance studies make therapeutic strategies more dynamic and individualized for each patient and situation. In any case, it is mandatory to ensure a perfect adherence to ART from the patients.

Immunological benefits of antiretroviral therapy in very early stages of asymptomatic chronic HIV-1 infection

OBJECTIVES

To assess whether an almost complete restoration of immune system can be achieved when antiretroviral therapy is initiated at very early stages of asymptomatic chronic HIV-1 infection.

DESIGN

T cell subsets and cell-mediated responses were analysed at baseline and after 12 months of either a double or a triple antiretroviral therapy in 26 asymptomatic HIV-1-infected patients with CD4 T cell counts > 500 x 10(6) cells/l and a baseline plasma viral load > 10000 copies/ml.

RESULTS

Triple therapy was significantly more effective in reducing plasma HIV RNA to undetectable levels, in returning CD4:CD8 ratio to nearly normal levels, in reducing activated cells (CD38) and in increasing naive (CD45RA+CD45RO-) and memory (CD45RA-CD45RO+) CD4 cells. Both double and triple therapies caused a clear decrease in memory (CD45RA-CD45RO+) CD8 cells as well as a significant increase in the CD28 subset of CD8 cells. At baseline, there was an important increase in cells producing interferon-gamma (IFNgamma) with no significant abnormalities in T lymphocytes producing interleukin 2 (IL-2), tumour necrosis factor alpha and interleukin 4. Both types of therapy reduced IFNgamma- and IL2-producing CD4 T lymphocytes while IFNgamma-producing CD8 cells remained increased. Even before therapy, these HIV-1-positive patients lacked significant abnormalities in the T cell responsiveness to polyclonal stimuli as well as in the secretion of CCR5 chemokines by peripheral blood mononuclear cells.

CONCLUSIONS

Initiating highly active antiretroviral therapy at very early stages of chronic HIV-1 infection allows rapid and almost complete normalization of T cell subsets and preservation of T cell functions. These early-treated patients could be excellent candidates for receiving additional HIV-specific immune-based therapies, which might be essential for the control of HIV infection.

Comparison of immunologic restoration and virologic response in plasma, tonsillar tissue, and cerebrospinal fluid in HIV-1-infected patients treated with double versus triple antiretroviral therapy in very early stages: The Spanish EARTH-2 Study. Early Anti-Retroviral Therapy Study

The objective of antiretroviral therapy is to obtain an almost complete and durable suppression of viral replication in all compartments to facilitate recovery of the immune system. We assessed the virologic effect in plasma, tonsillar tissue, and cerebrospinal fluid (CSF) in 94 HIV-1-infected patients with CD4 counts >500 x 106 cells per liter and viral load >5000 copies/ml randomly assigned to triple antiretroviral therapy (two nucleoside reverse transcriptase inhibitors (NRTIs) plus one protease inhibitor) versus double therapy (two NRTIs). We also analyzed the immunologic recovery in this cohort of patients. Lymphoid tissue and cerebrospinal fluid viral load, development of genotypic resistance, proliferative responses to HIV-1 specific antigens, and other immunophenotypic markers were analyzed. The proportion of patients who achieved a decrease in HIV RNA levels to <200 copies/ml was significantly greater in the triple therapy group than in the two drug groups (p =.0002 for each pair-wise difference). At week 52, tonsillar tissue HIV RNA from 5 patients treated with triple therapy was lower than the limit of detection, whereas the mean +/- standard error in patients with double therapy (n = 5) was 5.03 +/- 0.34 copies/mg/tissue. In all 10 patients, CSF viral load (VL) was <20 HIV-1 RNA copies/ml at week 52. CSF cell counts and protein levels tended to decrease after 52 weeks of antiretroviral therapy. After 1 year of therapy, 13 of 21 patients (62%) in the double-therapy groups (zidovudine plus lamivudine [n = 9] and stavudine plus lamivudine [n = 12]) had evidence of M184V mutation. None of the 10 samples of patients receiving triple therapy could be amplified because of low HIV RNA levels. The mean increase in CD4 cells at week 52 was greater in the stavudine and lamivudine and indinavir group than in the double-treatment arms (186 versus 67 and 102, respectively; p =.03). In patients treated with triple therapy, the increase in naive T cells (CD4 and CD8) was greater than in patients treated with double therapy. Markers of activation decreased further in patients treated with the regimen that included protease inhibitors. Proliferative responses to HIV-1 p24 antigen were never recovered after double or triple therapy. Our study suggests that even in very early stages of HIV-1 disease only therapy with two NRTIs and one protease inhibitor reduces plasma, lymphoid tissue, and CSF VL to undetectable levels. HIV-1-related immune system abnormalities improved but were still defective after 1 year of antiretroviral therapy.

[Recommendation of GESIDA (AIDS Study Group)/National Plan on AIDS with respect to the anti-retroviral treatment in adult patients infected with the human immunodeficiency virus in the year 2000 (I)]

OBJECTIVE

To update the recommendations for antiretroviral therapy in adult HIV-infected persons according to the new scientific advances and the existence of new antiretroviral drugs in the last two years.

METHODS

The antiretroviral therapy recommendations have been condensed by a panel of experts from the Spanish AIDS Study Group (Grupo de Estudio de sida-GESIDA) of the Spanish Infectious Diseases and Clinical Microbiology Society (SEIMC) and from the Clinical Advisory Panel of the Secretariat of the Spanish National Plan on AIDS (SPNS) of the Ministry of Health. Three levels of evidence have been established depending if the data came from randomised and controlled studies, from cohort or case-control studies or from descriptive studies and expert opinions. For that purpose we have reviewed the advances in HIV pathophysiology and results of efficacy (clinical, virologic and immunologic) and security (toxicity) from clinical trials involving antiretroviral therapy lasting at least 12 months, from cohort studies and pharmacokinetic and security data of antiretroviral drugs, presented in international conferences or published in biomedical journals in the last two years. In each situation we have established either to recommend or to consider or not recommend antiretroviral therapy.

RESULTS

Nowadays, antiretroviral therapy consisting of at least three drugs constitutes the election therapy for chronic HIV infection, since it delays clinical progression, increases significantly the survival and diminishes hospital admissions and associated costs. The decision to start antiretroviral therapy must be based upon three elements: presence or absence of symptoms, plasma viral load and CD4+ cells counts. Thus, in asymptomatic cases with a high CD4+ cells count (> 500/microL) and low viral load (< 10,000 copies/ml by branched DNA [bDNA] or < 20,000 copies/ml by reverse-transcription polymerase chain reaction [RT-PCR] or nucleic acid sequence based amplification [NASBA]) we recommend to delay antiretroviral therapy. In symptomatic patients we recommend to start it, and in asymptomatic patients, we could recommend or consider antiretroviral therapy initiation depending on the risk of progression, established by the viral load and the CD4+ cells count. In any case, if therapy is started, the objective must be to reach an undetectable viral load (< 50 copies/ml). The adherence to antiretroviral therapy plays a key role for its initial moment and for the duration of the antiviral response, antiretroviral therapy can achieve a restoration of cellular immunity in the advanced patients. There are few therapeutic options in failing patients due to cross-resistance. Resistance studies can be useful in this setting. The toxicity is a new and limiting factor of antiretroviral therapy which requires to look for new therapeutic options. Antiretroviral therapy criteria for acute infection, pregnancy, post-exposure prophylaxis and when to use resistance testing are discussed.

CONCLUSIONS

In this moment, there is a more conservative attitude towards starting antiretroviral therapy than in previous recommendations in which a virus eradication was considered. On the other hand, the high number of disposable drugs, the more sensitive monitorization methods (plasma viral load) and the possibility of performing resistance studies make therapeutic strategies more dynamic and individualised for each patient and situation. In any case, it is mandatory to ensure a perfect adherence to antiretroviral therapy from the patients.

Correlation between electrocardiographic and ultrasonographic time-interval measurements in fetal lamb heart

The objective of this study was to establish the echocardiographic modality that best correlates with electrical events in the fetal heart. No documentation on the relationship between electrical events recorded with a surface ECG and fetal M-mode or Doppler echocardiographic measurements is available. The following ultrasound tracings were recorded simultaneously with a surface ECG on six exteriorized near-term fetal lambs: 1) M-mode echocardiography of atrial and ventricular contractions; and 2) Doppler flow velocity waveforms in the right superior vena cava (SVC) either alone or 3) in association with those of the ascending aorta. In the SVC, the onset of the retrograde A wave and the beginning of the forward wave during ventricular systole were used as markers for the start of the P wave and QRS complex, respectively. For the simultaneous SVC and ascending aorta tracings, the beginnings of the A and of the aortic ejection waves were used as markers. On average, the atrioventricular interval was 84 ms longer than the PR interval with the M-mode, corresponding to an increase of 107%. A similar observation was made for the simultaneous Doppler signals from SVC and ascending aorta, but the difference between the atrioventricular and PR intervals was smaller, averaging 35 ms. When the SVC Doppler was taken alone, no significant difference was found between atrioventricular and ventriculoatrial compared with PR and RP intervals, respectively, and a strong correlation was found between the two methods of measurement, both for the atrioventricular (r = 0.91) and ventriculoatrial (r = 0.89) intervals. Doppler interrogation of the SVC alone and, to a lesser degree, of the SVC and ascending aorta are reliable indirect markers for the timing of electrical events of the fetal lamb heart in sinus rhythm.

Thrice-weekly sulfadiazine-pyrimethamine for maintenance therapy of toxoplasmic encephalitis in HIV-infected patients. Spanish Toxoplasmosis Study Group

An open, randomised, multicentre trial was conducted to evaluate the efficacy of thrice-weekly versus daily therapy with sulfadiazine-pyrimethamine in the prevention of relapses of toxoplasmic encephalitis in HIV-infected patients. Between February 1994 and July 1997, 124 patients with HIV infection were enrolled after resolution of the first acute episode of toxoplasmic encephalitis treated with sulfadiazine-pyrimethamine. Patients were randomly assigned to receive either a daily regimen consisting of sulfadiazine (1 g) twice a day plus 25 mg pyrimethamine and 15 mg folinic acid daily (n = 58), or a thrice-weekly regimen consisting of the same doses of sulfadiazine and folinic acid plus 50 mg pyrimethamine (n = 66). After a median follow-up period of 11 months (range 1-39 months), no differences were found in the incidence of toxoplasmic encephalitis relapses between the groups, there being 14.9 episodes per 100 patient-years (95% CI: 2.8-20.2) in the daily-regimen group versus 14.1 episodes (95% CI: 2.3-17.2) in the intermittent-regimen group. The estimated cumulative percentages of relapse at 12 months were 17% and 19%, respectively (P = 0.91). In a Cox multivariate analysis, not taking antiretroviral therapy was the only variable independently associated with relapse (adjusted risk ratio: 4.08; 95%CI: 1.32-12.66). Baseline CD4+ cell counts, prior AIDS, mental status, sequelae and allocated maintenance therapy regimen were not independent predictors of relapse. No differences were observed in the survival rate (P = 0.42), or in the incidence of severe adverse effects (P = 0.79). The efficacy of the thrice-weekly regimen was similar to that of the daily regimen in the prevention of relapses of toxoplasmic encephalitis. Administration of antiretroviral therapy was the only factor associated with a lower incidence of relapse.

[The recommendations of GESIDA/SEFH/PNS for improving adherence to antiretroviral treatment. AIDS Study Group of the Spanish Society of Hospital Pharmacy and the National Plan on AIDS of the Minister of Health and Consumers]

The main objective of HAART is to achieve a complete suppression of the viral replication for long time. However, when the therapeutic drug levels are low, HIV can replicate and it can develop resistances. This fact can be the reason of treatment failure, HIV transmission of resistant strains and therefore an inappropriate use of the economical resources. In order to get the adequate therapeutic drug levels it is necessary to have a good adherence to the treatment. We review the factors that influence the adherence, the evaluation methods and we recommend the possible intervention strategies which should be given by a multidisciplinary team, integrated by physicians, pharmacists, nurses, psychologists and other personal support. To start HAART is not an emergency. For this reason is very important to prepare to the patient and to identify the non-adherence factors in order to correct it. Once the HAART is indicated it is very important to offer information during the medical prescription and when the drugs are dispensed. During the therapy is necessary to follow actively all patients on HAART. In order to make therapeutical decisions we need to know the patient drug adherence rate. We recommend to use several methods to calculate the drug adherence rate, being the most commonly used the patient interview, the patient questionnaire, the refill count, the pharmacy visits rate together with the viral load evolution of the patient. In order to get all this information it is necessary to have a very good communication between all the people involved in HIV infected patients care. If non-adherence is detected it is necessary to start the intervention strategies to correct it and if they fail it might be necessary in some cases to stop HAART. The potential benefits of the adherence programs can justify the economical spend in human and hospital facilities resources.

A randomized study comparing triple versus double antiretroviral therapy or no treatment in HIV-1-infected patients in very early stage disease: the Spanish Earth-1 study

BACKGROUND

Most current guidelines state that antiretroviral therapy should be considered for HIV-infected patients with plasma HIV RNA > 5000-10000 copies/ml and CD4 cells > 500 x 10(6) cells/l. However, there is increasing concern about whether this is the optimal point to begin treatment or whether it is better to delay the initiation to more advanced stages.

OBJECTIVE

To study the immunological and virological benefits of starting antiretroviral therapy at these early stages.

METHODS

A total of 161 HIV-infected asymptomatic patients with CD4 cell count > 500 x 10(6) cells/l and viral load > 10000 copies/ml were randomly assigned to one of five treatment groups: no treatment, twice daily zidovudine and thrice daily zalcitabine (ZDV-ddC), twice daily zidovudine and didanosine (ZDV-ddI), twice daily stavudine and didanosine (D4T-ddI), or a twice daily three-drug regimen with stavudine and lamivudine and ritonavir. The endpoints were progression to < 350 x 10(6) cells/l CD4 cells, to < 500 x 10(6) cells/l with either two Centers for Disease Control class B symptoms or an increase of viral load > 0.5 log10 copies/ml above baseline, or to AIDS or death. In various substudies, the lymphoid tissue and cerebrospinal fluid viral load, development of genotypic resistance, proliferative responses to mitogens and cytomegalovirus, and HIV-1 specific antigens and other immunophenotypic markers were also analysed.

RESULTS

Progression rates to study endpoints within 1 year were greater in the control group (31%) than in all groups receiving antiretroviral therapy pooled together (5%; estimated hazard ratio 7.41; 95% confidence interval 5.72-74.55; P < 0.001). The peak mean viral load decrease was greater in the three-drug group when compared with any of the three groups with a two-drug regimen (2.32, 1.65, 1.72 and 1.84, respectively; P < or = 0.001). At 1 year, viral load remained below 20 copies/ml in 30 out of 33 patients in the three-drug group (91%) and in only eight out of 94 patients (9%) in two-drug groups (P = 0.001). The peak mean increase in CD4 cells was also greater in the three-drug group than in the double treatment arms (259 versus 85, 144 and 145 x 10(6) cells/l, respectively; P = 0.001). By comparison, 36% of patients in the three-drug group regimen had to change the therapy as a result of adverse events. Substudies were performed in 60 patients recruited at two sites. Tonsillar tissue HIV RNA was measured in seven patients (two in the two-drug groups and five in the three-drug group) in whom plasma HIV RNA was < 20 copies/ml at 1 year. It was 15151 and 133333 copies/mg tissue in the two patients from the two-drug group, < 40 copies/mg tissue in four patients in the three-drug group, and 485 copies/mg in one patient in the three-drug group. At 1 year there was a mean increase of 4.21+/-2.94% in CD8+CD38+ cells in the control group and a decrease of 9.48+/-3.36% in the two-drug groups (P = 0.01), and 19.87+/-3.64 in the three-drug group (P = 0.001 and P = 0.05, for comparisons with control group and two-drug groups, respectively). Although proliferative responses to cytomegalovirus antigens were significantly greater in those receiving antiretroviral therapy, response to HIV-1 p24 antigen was not detected in any patient in either treatment group.

CONCLUSIONS

This study supports the recommendation to start antiretroviral therapy with a three-drug combination during very early stages of HIV-1 disease, at least if viral load is above a cut-off point (10000 copies/ml in our study). The risk of progression was sevenfold higher in non-treated patients at 8 months of follow-up. Some immune system parameters improved toward normal values after 1 year of antiretroviral therapy, but the proliferative response of CD4 T lymphocytes against the p24 HIV-1 antigen was not recovered. Therapeutic approaches with more potent, better-tolerated and more convenient regimens will increasingly favour early intervention with antiretroviral t

Internal hernias and gastric perforation after a laparoscopic gastric bypass

A 27-year-old woman underwent laparoscopic Rouxen-Y gastric bypass. A retrocolic-retrogastric herniation of most of the small bowel and later a gastric perforation due to internal hernia at the mesenteric defect of the jejuno-jejunostomy occurred. These unusual, but not rare, complications are directly related to the neoanatomy that follows gastric bypass and can lead to rapidly progressing and life-threatening situations. Proper evaluation of clinical signs and symptoms, early abdominal CT scan, and urgent operative intervention are mandatory to achieve a successful outcome.

[Electroencephalographic and hemodynamic monitoring at various desflurane concentrations]

OBJECTIVES

To assess the electroencephalographic patterns and hemodynamic changes produced by desflurane at 0.5, 1 and 1.5 MAC.

MATERIAL AND METHODS

Twenty-four patients undergoing gynecological surgery under general anesthesia were enrolled prospectively. We monitored electroencephalographic (EEG) patterns and hemodynamic parameters as well as inspired and expired desflurane fractions. Anesthetic induction was with 2 mg/kg of propofol, 2 to 3 mg/kg of fentanyl and 0.1 mg/kg vecuronium. Spectral edge frequency (SEF90) and the EEG delta ratio were recorded along with mean systolic and diastolic pressures, heart rate, oxygen saturation and expired CO2 fraction during induction, intubation, 5 min after intubation and at 0.5, 1 and 1.5 MAC during weaning from anesthesia and extubation.

RESULTS

Blood pressure fell significantly at 1.5 MAC and increased when anesthesia was withdrawn; heart rate did not change significantly. SEF90 and the delta ratio changed, however, at each phase. SEF90 fell notably at the moment of induction but gradually increased, rising upon intubation, 5 min later, at 0.5 MAC and upon withdrawal of anesthesia. A significant decrease in SEF90 appeared when 1.5 MAC was reached, related to achievement of a deeper plane of anesthesia.

CONCLUSIONS

Automated EEG processing can provide a good measure of depth of anesthesia, as it reflects significant changes related to level of anesthesia at each phase. These differences are not always observable with routine monitoring of hemodynamic parameters.

Design of a one-tube hemi-nested PCR for detection of Toxoplasma gondii and comparison of three DNA purification methods

The aims of the present study were to design an easy and sensitive DNA amplification method for detection of Toxoplasma gondii with low risk of accidental contamination, and to find a rapid method for purification of clinical samples containing potential inhibitors of the amplification reaction. With a pair of primers amplifying a 619-bp fragment of the B1 gene of this parasite it was possible to detect DNA equivalent to 10 parasites. When a third primer was added to the same tube, sensitivity increased to 0.1 parasite. In a comparison of different DNA purification methods, the High Pure PCR Template Preparation Kit (Boehringer Mannheim, Germany) gave the best results. With this purification method and the one-tube hemi-nested PCR, T. gondii DNA was detected in 14 (87.5%) of 16 clinical specimens (amniotic fluid, broncho-alveolar lavage, bone marrow, blood, liver biopsy) in which the parasite was demonstrated by cell culture.

Cerebrospinal fluid HIV-1 RNA levels in asymptomatic patients with early stage chronic HIV-1 infection: support for the hypothesis of local virus replication

OBJECTIVE

To assess HIV-1 RNA levels in cerebrospinal fluid (CSF) and their potential correlation with plasma viral load and central nervous system (CNS) HIV-1 infection markers in stable asymptomatic patients with a CD4 T cell count >500x10(6) cells/l.

PATIENTS AND METHODS

Consecutive patients screened for two trials were eligible for lumbar puncture assessment. At day 0, simultaneous samples of CSF and plasma were obtained and levels of total proteins, albumin, IgG, antibodies against HIV-1 p24 antigen, HIV-1 RNA (using the polymerase chain technique) and white cells were measured.

RESULTS

The integrity of the blood-brain barrier was preserved (albumin index > or =7) in 59 out of 70 patients (84%). Intrathecal production of antibodies against HIV-1 p24 antigen was demonstrated in 55 out of 70 individuals (78%). Viral load in CSF was significantly lower than plasma values (3.13+/-0.95 versus 4.53+/-0.53, P = 0.0001). HIV-1 RNA was not detected in CSF in only three of the 70 patients (4%). Overall, there was a significant correlation between plasma and CSF HIV-1 RNA levels (r = 0.43, P = 0.0001); however, in 29 patients (41%) there were significant differences (>1.5 log10 copies/ml) between the viral loads in plasma and CSF. In the multivariate analysis, a high level of protein and white cells in CSF, but not the HIV-1 RNA plasma level, were factors independently associated with a higher level of HIV-1 RNA in CSF (P = 0.0001).

CONCLUSIONS

HIV-1 RNA can be detected almost always in CSF of asymptomatic patients in early stages of HIV-1 infection including those with a preserved integrity of the blood-brain barrier. The important discrepancies between plasma and CSF viral load, and the independent association between CSF abnormalities and CSF viral load, support the hypothesis of local production of HIV-1.

Influence of environmental temperature on incidence of indinavir-related nephrolithiasis

We analyzed the influence of temperature, humidity, and atmospheric pressure on the 1-year incidence of nephrolithiasis among human immunodeficiency virus type 1-infected patients treated with indinavir. One hundred three patients (13.6%) developed 326 episodes of nephrolithiasis. Eighty-two patients (79.6%) had more than one episode (range, two to seven episodes). The overall incidence ranged from 0 to 10.2 episodes per 100 patients exposed per month. There was a significant correlation between temperature and the overall incidence of nephrolithiasis and the incidence of recurrences but not with the incidence of first episodes. Nephrolithiasis was not related to humidity or atmospheric pressure. Our data support the standard recommendation of drinking at least 1.5 L of water daily to prevent nephrolithiasis in most patients treated with indinavir irrespective of meteorologic factors. However, the risk of nephrolithiasis is higher for a certain subgroup of patients when the environment is hot irrespective of adequate water intake.

Dynamics of viral load rebound and immunological changes after stopping effective antiretroviral therapy

BACKGROUND

This study addresses the dynamic of viral load rebound and immune system changes in a cohort of eight consecutive HIV-1-infected patients in very early stages [all the patients were taking highly active antiretroviral therapy (HAART} and were recruited in the coordinating center from a larger study] who decided to discontinue HAART after 1 year of treatment and effective virologic response. The safety of this procedure and the outcome with reintroduction of the same treatment was also investigated.

METHODS

Plasma, cerebrospinal fluid (CSF), and lymphatic tissue viral loads were measured at baseline; lymphocyte immunophenotyping and CD4 lymphocyte proliferative responses to mitogens and specific antigens were assessed. The same antiretroviral therapy was reintroduced as soon as plasma viral load became detectable (above 200 copies/ml).

RESULTS

At day 0, plasma viral load was below 20 copies/ml in all eight patients (and below 5 copies/ml in five of eight patients). A rebound in plasma viral load was detected in all patients from day 3 to day 31 with a mean doubling time of 2.01 (SE 0.29) days. Three out of eight patients achieved a peak plasma viral load at least 0.5 log10 above baseline, pretreatment values. Mutations associated with resistance to reverse transcriptase or protease inhibitors were not detected. After 31 days off therapy, CD4 lymphocytes decreased [mean 45% (SE 4) to 37% (SE 3); P = 0.04], CD8+CD28+ lymphocytes decreased [mean 59% (SE 5) to 43% (SE 4); P = 0.03], and CD8+CD38+ lymphocytes increased [mean 55% (SE 3) to 66% (SE 4); P = 0.009]. Mean stimulation indices of lymphocytes treated with phytohemagglutinin (PHA) and CD3 decreased from day 0 to day 31 from 34% (SE 8) to 17% (SE 9) (P = 0.06) and from 24% (SE 8) to 5% (SE 2) (P = 0.02), respectively. These changes were mainly contributed by the group of five patients with plasma viral load below 5 copies/ml at day 0. Viral load dropped below 20 copies/ml in all patients after 1 month of restarting the same antiretroviral regimen.

CONCLUSIONS

Discontinuation of HAART after 1 year of successful treatment is followed by a rapid rebound of viral load; this rapidly returns to undetectable levels following reintroduction of the same treatment. In patients with more effective control of virus replication (viremia below 5 copise/ml), discontinuation of treatment was associated with more severe impairment of immunologic parameters.

[Disseminated cryptococcosis in patients with AIDS. Prognostic factors of poor outcome]

BACKGROUND

The objectives of this study were to analyze the changes in the incidence of cryptococcal disease in the last 10 years (1987-1997) and to assess the factors of poor prognosis in HIV-1 infected patients.

PATIENTS AND METHODS

Clinical records of HIV-1 infected patients diagnosed with cryptococcal infection from June 1987 to December 1997 at Hospital Clinic i Provincial in Barcelona, Spain, were examined. An univariate and multivariate analysis of the predictors of poor outcome was performed.

RESULTS

Sixty clinical records were analyzed. The number of cases per 100 exposed patients per year decreased from 1991 to 1993 and, afterwards, decreased again from 1996. Fifty patients had a resolution of clinical symptoms, 17 out of this 50 patients (34%) had a relapse. Factors associated with a higher risk of relapse were a positive blood culture and cryptococcal antigen title in cerebrospinal fluid above 1/1.024.

CONCLUSIONS

The decrease in the number of cases of cryptococcal infection coincides with the broad use of triazole antifungal drugs for oral candidiasis (1990-1991) and, afterwards, with the initiation of highly active antiretroviral therapy (1996). The best predictors of relapse are a positive blood cryptococcal culture and a high titter of cryptococcal antigen.

Influence of human immunodeficiency virus 1 infection and degree of immunosuppression in the clinical characteristics and outcome of infective endocarditis in intravenous drug users

BACKGROUND

Immunosuppression caused by human immunodeficiency virus 1 (HIV) infection appears to modify the clinical characteristics and to increase the severity of several bacterial infections. The impact of HIV infection and the degree of immunosuppression on the clinical characteristics and outcome of infective endocarditis (IE) in intravenous (IV) drug users has not been well characterized.

METHODS

Prospective cohort study among 292 consecutive IV drug users with IE diagnosed in 2 academic institutional hospitals in Barcelona, Spain, from January 1, 1984, to October 31, 1995. Serostatus of HIV infection was documented in 283 patients. We measured demographics, clinical and biological data, cause, echocardiographic findings, HIV serostatus and classification, CD4 cell count, complications, and mortality.

RESULTS

Among the 283 episodes of IE, 216 (76.3%) were in HIV-infected patients and 67 (23.7%) in non-HIV-infected patients. Rate of IE per 1000 admissions ranged from 0.17 to 0.82 per year, peaking in 1989. Characteristics of IE independently associated with HIV infection were right-side involvement (odds ratio [OR], 7.6; 95% confidence interval [CI], 3.5-16.7), a micro-organism different from viridans streptococci (OR, 2.5; 95% CI, 1.1-5.9), duration of drug abuse longer than 5 years (OR, 5.0; 95% CI, 2.4-10.3), and white blood cell count of no more than 10 X 10(9)/L (OR, 2.2; 95% CI, 1.1-4.2). There were no significant differences in mortality due to IE according to HIV serostatus. Among the 216 patients with HIV infection, the variables independently associated with worse outcome were CD4 cell count lower than 0.200 x 10(9)/L and left-sided or mixed IE.

CONCLUSIONS

Although there is a difference in clinical presentation in IE in IV drug users, outcome was similar according to their HIV status. However, among HIV-infected patients, severe immunosuppression and mixed or left-side valvular involvement were strong risk factors for mortality.