Quantitative Chest CT Analysis to Measure Short-Term Sequelae of COVID-19 Pneumonia: A Monocentric Prospective Study.

(1) Background: Quantitative CT analysis (QCT) has demonstrated promising results in the prognosis prediction of patients affected by COVID-19. We implemented QCT not only at diagnosis but also at short-term follow-up, pairing it with a clinical examination in search of a correlation between residual respiratory symptoms and abnormal QCT results. (2) Methods: In this prospective monocentric trial performed during the "first wave" of the Italian pandemic, i.e., from March to May 2020, we aimed to test the relationship between %deltaCL (variation of %CL-compromised lung volume) and variations of symptoms-dyspnea, cough and chest pain-at follow-up clinical assessment after hospitalization. (3) Results: 282 patients (95 females, 34%) with a median age of 60 years (IQR, 51-69) were included. We reported a correlation between changing lung abnormalities measured by QCT, and residual symptoms at short-term follow up after COVID-19 pneumonia. Independently from age, a low percentage of surviving patients (1-4%) may present residual respiratory symptoms at approximately two months after discharge. QCT was able to quantify the extent of residual lung damage underlying such symptoms, as the reduction of both %PAL (poorly aerated lung) and %CL volumes was correlated to their disappearance. (4) Conclusions QCT may be used as an objective metric for the measurement of COVID-19 sequelae.

Risk Factors for Early Cytomegalovirus Reactivation and Impact of Early Cytomegalovirus Reactivation on Clinical Outcomes after T Cell-Replete Haploidentical Transplantation with Post-Transplantation Cyclophosphamide.

Risk factors for cytomegalovirus (CMV) reactivation and the impact of CMV reactivation on patient outcomes have been extensively investigated after matched related or unrelated donor transplantation, but little is known in the setting of haploidentical stem cell transplantation (Haplo-SCT) with post-transplantation cyclophosphamide (PT-Cy), in which recipients are considered more severely immunocompromised. We retrospectively analyzed a cohort of 554 consecutive patients undergoing Haplo-SCT with PT-Cy at 3 different centers. Early CMV reactivation (occurring within the first 120 days post-transplantation) occurred in 242 patients, for an estimated cumulative incidence of 44%. Among those patients, 74 (30%) had recurrent CMV and 20 (8%) had CMV disease. On multivariable analysis, positive recipient CMV serostatus (hazard ratio [HR] >2.5; P < .001), disease histology (lymphoid versus myeloid: HR, 0.66; P = .003) and increasing recipient age (HR, 1.01; P = .015) were independent predictors of CMV reactivation. At a 4-month landmark analysis, CMV reactivation was associated with higher 1-year and 5-year cumulative incidence of nonrelapse mortality (NRM) relative to patients without reactivation: 13% versus 5% and 22% versus 9%, respectively (P < .001). On multivariable analysis, CMV reactivation was an independent negative predictor of NRM (HR, 2.69; P < .001) and was close to statistically significant for overall survival (HR, 1.38; P = .062). Our results suggest that CMV reactivation plays an important role at determining NRM. Because patient CMV serostatus is the main predictor of CMV reactivation, it should be considered when evaluating strategies for preventing CMV reactivation. 2022 American Society for Transplantation and Cellular Therapy. Published by Elsevier Inc.

Efficacy and safety of dalbavancin in the treatment of acute bacterial skin and skin structure infections (ABSSSIs) and other infections in a real-life setting: data from an Italian observational multicentric study (DALBITA study).

OBJECTIVES: We evaluated the efficacy and safety of dalbavancin in ABSSSI and 'other sites' infections' (OTA). METHODS: Observational study involving 11 Italian hospitals including patients that received ≥1 dose of dalbavancin in 2016-2019. The outcome was end-of-treatment efficacy and safety in ABSSSI and OTA in a real-life setting. RESULTS: 206 patients enrolled (males 50%, median age 62 [IQR 50-76] years), 60.2% ABSSSI, 39.8% OTA. 69.7% ABSSSI vs 90.7% OTA (p = 0.003) and 46.3% ABSSSI vs 37.2% OTA (p = 0.786) received previous and concomitant antibiotics, respectively. 82.5% reached clinical cure . Eleven (5.4%) patients had non-serious adverse events (AE). OTA patients showed longer hospitalization (13.5 days, 5.5-22 vs 3, 0-11.7; p<0.0001) and received longer previous (18 days, 9-30 vs 11, 7-19; p = 0.007)/concomitant antibiotic treatments (21 days, 14-52 vs 11, 8-14; p < 0.0001), compared to ABSSSI. ABSSSI and OTA showed similar efficacy (85.5% vs 75%, p = 0.459) and safety (no AE: 81.5% vs 64.3%, p = 0.258); efficacy was independent of previous/concomitant therapies. CONCLUSIONS: Dalbavancin demonstrated a success rate of >80%, with similar efficacy/safety in ABSSSI and off-label indications. The preferential use of dalbavancin as second-line or combination therapy would seem to suggest the need for in-depth studies focused on its off-label use.

Caspofungin for primary antifungal prophylaxis after T-cell-replete haploidentical stem cell transplantation with post-transplant cyclophosphamide.

OBJECTIVES: T-cell-replete haploidentical stem cell transplantation (Haplo-SCT) with post-transplant cyclophosphamide (PT-Cy) is at high risk of invasive fungal infections (IFI), and anti-mold-active drug is required for primary antifungal prophylaxis (PAP) according to international guidelines. No data are available on the efficacy of caspofungin as PAP in this setting. METHODS: Here, we report our retrospective experience with 103 consecutive patients treated with caspofungin as PAP after Haplo-SCT. Caspofungin was administered only during the pre-engraftment phase. RESULTS: Hundred-day cumulative incidence of proven-probable IFI (PP-IFI) was 8.7% and median day of onset was 19 post-SCT. No patient died of PP-IFI, and overall survival (OS) and non-relapse mortality (NRM) hazard ratio (HR) for patients experiencing IFI were 1.02 (P = 0.9) and 0.7 (P = 0.7), respectively. Three-year overall survival (OS) and 1-year non-relapse mortality (NRM) were 55% and 19%, respectively. By univariate analysis, duration of neutropenic phase and partial remission pre-transplant disease status were associated with increased incidence of IFI, but were not confirmed by multivariate analysis. CONCLUSION: In summary, PAP with caspofungin is an effective strategy for preventing IFI in the context of Haplo-SCT with PT-Cy. Further efforts are required in order to identify more potent strategies able to avoid the occurrence of breakthrough infections.

Efficacy of intraventricular amikacin treatment in pan-resistant Pseudomonas aeruginosa postsurgical meningitis.

BACKGROUND: We describe a case of pan-resistant Pseudomonas aeruginosa postsurgical meningitis associated with the presence of an external ventricular device. We changed therapy twice; finally, by using amikacin and a continuous infusion of cefepime, we obtained clinical improvement. CASE PRESENTATION: A female patient, who underwent surgery for a cavernous angioma, presented with meningitis. Cerebrospinal fluid culture revealed a multidrug-resistant Pseudomonas aeruginosa, initially sensitive only to colistin. We successfully used intrathecal amikacin and intravenous cefepime continuous infusion plus intravenous amikacin after two previous ineffective therapeutic approaches. CONCLUSION: The evaluation of the antibiotic concentration and the bactericidal activity in cerebrospinal fluid may contribute to the choice of the drug in cases of multidrug-resistant meningitis.

A reduced dose of fluconazole as primary antifungal prophylaxis is not associated with increased risk of invasive fungal infections after allogeneic stem cell transplantation from a HLA identical sibling.

BACKGROUND: Invasive fungal infections (IFI) represent a common side effect of allogeneic hematopoietic stem cell transplant (allo-SCT), resulting in increased non relapse mortality (NRM) and reduced overall survival (OS) rates. Seventy-five days of Fluconazole 400 mg/d represents the standard primary antifungal prophylaxis (PAP) after allo-SCT, especially for low-risk transplants. However, the ideal dosage of fluconazole has never been tested. METHODS: Here, we report the experience of our institution on 113 consecutive patients receiving an allo-SCT from a HLA identical sibling between 1999 and 2015, where PAP consisted of fluconazole 100 mg/d only during the pre-engraftment phase. At the time of transplant, all patients were considered at low-risk for mold infection according to ECIL-5 guidelines. RESULTS: Cumulative incidence of possible-probable-proven IFI was 11.7%, while proven-probable (PP-IFI) occurred in 5.5% of patients by day 100 post transplant. Of note, only 1 patient developed invasive Candidiasis due to a non-albicans strain and stool-screening tests were negative for colonization by Candida albicans species. The incidence of 1-year acute and 2-year chronic graft-versus-host-disease (GVHD) was 30% and 45%, respectively. Three-year OS and 1-year NRM were 53% and 11.3%, respectively. CONCLUSION: In summary, fungal prophylaxis with fluconazole 100 mg/d results in very low incidence of PP-IFI, GVHD and NRM in low-risk allo-SCT.

Genomic Integration of HHV-6 Mimicking Viral Reactivation after Autologous Stem Cell Transplantation.

The monitoring of Human Herpesvirus 6 (HHV-6) after allogeneic stem cell transplantation has proven to be useful in preventing life-threatening complications; however, the pathogenic role of HHV-6 after autologous transplantation is not well-characterized, although viral reactivation might be responsible for significant complications even after this type of transplant. Here we report, for the first time to our knowledge, the case of a patient with chromosomally integrated HHV-6 (ciHHV-6), presenting with high titers of HHV-6 DNA copies after autologous transplantation, mimicking HHV-6 reactivation. The presence of viral DNA in the follicle bulb confirmed the ciHHV-6 and allowed for the discontinuation of the antiviral treatment. Due to the increasing awareness of HHV-6 potential pathogenicity and the fact that ciHHV-6 is expected in 1-2% of the population, such a case might be helpful in recognizing ci HHV-6, thus avoiding unnecessary and potentially toxic antiviral therapy once the viral genomic integration is confirmed.

Steatohepatitis in HIV-infected subjects: pathogenesis, clinical impact and implications in clinical management.

Antiretroviral medications have significantly improved the prognosis of subjects infected by human immunodeficiency virus (HIV). However, long-term complications of these drugs are increasingly recognized as significant causes of morbidity and mortality. Non-alcoholic fatty liver disease (NAFLD), which can evolve into non-alcoholic steato-hepatitis (NASH), cirrhosis and ultimately hepatic failure is one of the more often observed complications in the current clinical practice and the correlation with liver enzyme elevations is controversial. Multiple factors have been considered as possibly correlated to this event in the HIV-infected population, including metabolic abnormalities (such as hyperlipidaemia, hyperglycaemia and being overweight), chronic inflammation, concurrent infection with hepatitis C and B viruses, and treatment with certain nucleoside reverse transcriptase inhibitors (NRTI). HIV-associated syndromes such as lactic acidosis and lypodystrophy are frequently associated with fatty liver disease and a mitochondrial injury has been considered as its possible pathogenetic factor. In particular, treatment containing stavudine and didanosine have proven to be the most commonly implicated in the occurrence of mitochondrial abnormalities. Epidemiologic data to better define the role of predictive factors and drugs associated with the development of NAFLD are still lacking. Furthermore, it remains unclear the better therapeutic management for this condition, even if the current best therapeutic option for NAFLD is the treatment of the underlying disease. Other studies are mandatory to better elucidate the pathogenesis of NAFLD and the optimal therapeutic strategy for the underlying conditions.

Long-term immunologic outcome in HAART-experienced subjects receiving lopinavir/ritonavir.

The long-term immunological efficacy of regimens including lopinavir/ritonavir (LPV/r) has not been assessed in HIV-infected HAART-experienced subjects. The present study included 452 consecutive HIV-infected outpatients starting LPV/r before May 2003 after failing (HIV-RNA > 1000 copies/ml) HAART. Four groups were considered according to CD4 cell counts at LPV/r initiation: group 1 (G1, n = 115) < 100 cells/mm(3); group 2 (G2, n = 113) 100-199 cells/mm(3); group 3 (G3, n = 115) 200-349 cells/mm(3); group 4 (G4, n = 109) >/= 350 cells/mm(3). The majority of patients were males (n = 320, 70.8%), the median age was 38 years, and 180 (39.6%) were on CDC stage C. The median time of previous HAART was 51.1 months (12-81.7) and a median of 7 antiretroviral regimens and of 3 protease inhibitors was changed before LPV/r. The mean CD4 cell count increase was 105, 113, 128, and 144 cells/mm(3) after 12 months (p < 0.01 for each group) and 128, 106, 90, and 100 cells/mm(3) at month 48 (p < 0.01 for each group) in G1, G2, G3, and G4, respectively. The mean increase was comparable among the four groups. The on treatment analysis showed a better immunologic response among G1 and G2 patients from month 36. Forty-seven patients (10.4%), mainly in G1 and G2, maintained LPV/r despite persistent HIV-RNA > 1000 copies/ml. A mean increase of 64 and 65 cells/mm(3) and of 88 and 56 cells/mm(3) at month 12 and 48 was observed in G1 and G2, respectively. The use of LPV/r-based regimens also provided a durable immunologic recovery in highly pretreated HIV-infected subjects.

Tenofovir plus didanosine as Nrti backbone in HIV-infected subjects.

Nucleoside reverse transcriptase inhibitors (NRTI) are essential components of highly active antiretroviral treatment (HAART). Although several combinations can be used as NRTI backbones, not all are associated with good virological and/or immunological results. In particular, some NRTI combinations should be avoided due to antagonism (zidovudine plus stavudine) or to high rate of toxicity (didanosine plus stavudine). Tenofovir (TDF) and didanosine (ddI) are among the more often prescribed NRTI for their convenient posology (one pill each per day), relatively high genetic barrier for resistance, quite acceptable safety profile and remarkable antiviral potency when such drugs have been used as single drug or in combinations with other NRTIs. However, antiretroviral regimens containing TDF and ddI have been associated with a high rate of virological failure in HIV-infected naïve patients due to possible drug-interactions. The virological efficacy of this backbone in HIV-infected, HAART pre-treated subjects, is still controversial. Aim of this review is to assess the possible role that antiretroviral regimens containing TDF and ddI can have in the treatment of HIV-positive subjects, focusing on their plasmatic and/or intracellular interactions to optimize the antiretroviral efficacy and minimize the toxicities of this combination.

Subclinical hypothyroidism in HIV-infected subjects.

OBJECTIVES: The correlation between subclinical hypothyroidism [thyroid stimulating hormone (TSH)>4 mIU/L with normal free triiodothyroxine and free thyroxine levels], HIV infection and HAART is still unclear. PATIENTS AND METHODS: To evaluate the predictive factors of subclinical hypothyroidism in an HIV-infected population, we identified three groups of subjects: G1, subjects on stable highly active antiretroviral therapy (HAART) (for at least 1 year) at baseline and at month 24 (n=97); G2, subjects naive at both baseline and month 24 (n=47); G3, subjects starting HAART at baseline (n=46). RESULTS: The three groups were comparable with respect to age, gender, body weight and prevalence of HCV infection. At baseline, subclinical hypothyroidism was detected in 14 subjects in G1 (14.4%), 5 in G2 (10.6%) and 4 in G3 (8.7%) (P=0.18) and these were excluded from the analysis. At month 24, 15 subjects had developed subclinical hypothyroidism: 4 in G1 (4.8%), 3 in G2 (7.1%) and 8 in G3 (19.0%). In the multivariable analysis, the higher increase in total cholesterol was predictive of subclinical hypothyroidism (RR: 1.53 for each additional 10 mg/dL, 95% CI 1.23-1.90; P<0.01); other variables, which were statistically significant in the univariate analysis, such as G3 group, body weight and higher increase in CD4+ cell count and in triglyceride serum levels were not confirmed to be associated with TSH alterations. CONCLUSIONS: The occurrence of subclinical hypothyroidism in HIV-positive patients seems to be related to the increase in total cholesterol serum levels occurring after HAART initiation. Thyroid function should be monitored in all HIV-infected subjects, especially in those starting HAART.

Predictive factors of hyperlipidemia in HIV-infected subjects receiving lopinavir/ritonavir.

We studied 382 multiexperienced HIV-infected patients followed up for > or =3 months after starting lopinavir/ritonavir (LPV/r) to identify the factors predicting hypertriglyceridemia and high non-HDL cholesterol levels (triglycerides > or =200 mg/dl and/or non-HDL cholesterol > or =190 mg/dl) after 6 and 12 months of LPV/r exposure. The predictors of hypertriglyceridemia were higher baseline triglyceride levels [OR: 2.28 (95% CI: 1.67-3.12) for each additional 100 mg/dl; p = 0.001], the total duration of antiretroviral treatment [OR: 1.26 (95% CI: 1.12-1.41) for each additional year; p = 0.01], CDC stage C (OR: 2.06; 95% CI: 1.24-3.88; p = 0.02), and male gender (OR: 2.52; 95% CI: 1.42-4.74; p = 0.02); intravenous drug abusers seem less likely to develop the event (OR: 0.52; 95% CI: 0.37-0.92; p = 0.03). The predictors of high non-HDL cholesterol levels were higher baseline levels [OR: 3.92 (95% CI: 1.92-6.24) for each additional 100 mg/dl; p = 0.001) and the combination of NRTIs and NNRTIs with LPV/r (OR: 1.83; 95% CI: 1.10-3.69; p = 0.03). The 75 patients stopping LPV/r showed a significant reduction in median triglyceride and non-HDL cholesterol levels after 3 months of 39 mg/dl and 20 mg/dl (p = 0.01 for both), respectively. Patients with high triglyceride and non- HDL cholesterol levels at the start of LPV/r treatment are at higher risk of developing hyperlipidemia.

Predictive factors of lopinavir/ritonavir discontinuation for drug-related toxicity: results from a cohort of 416 multi-experienced HIV-infected individuals.

The objective of this study was to find predictive factors of lopinavir/ritonavir (LPV/r) discontinuation for drug-related toxicities in highly pre-treated human immunodeficiency virus (HIV)-infected subjects. The study was an observational study of HIV patients starting LPV/r with HIV RNA > 3log10 copies/mL and a follow-up > or = 6 months. Parameters studied were HIV RNA, CD4+ cell counts, metabolic parameters and drug-related adverse events. Acquired immune deficiency syndrome (AIDS) events and deaths were recorded. The Kaplan-Meier (KM) model was used to estimate time-dependent probability, and the multivariable Cox model to identify predictors of LPV/r discontinuation for adverse events. The study evaluated 416 HIV-infected patients. Seventy-seven patients (18.5%) discontinued LPV/r for toxicities. Adverse events leading to LPV/r discontinuation were gastrointestinal symptoms in 40 cases, hyperlipidaemia in 27 and increase of aspartate aminotransferase (AST)/alanine aminotransferase (ALT) in 10 patients. Nineteen patients (4.6%) developed an AIDS event during observation and 15 (3.6%) died. The KM probability of LPV/r discontinuation for toxicities was 5.3% (range 3.1-7.5%) at month 12 and 15.7% (range 12.1-19.3%) at month 24. Subjects with hepatitis C virus (HCV)-HIV co-infection (odds ratio (OR) 7.40; 95% confidence interval (CI) 3.73-14.66 versus HCV-negative; P = 0.001) and receiving LPV/r plus nucleoside reverse transcriptase inhibitors (NRTIs) and protease inhibitor (PI)/non-nucleoside reverse transcriptase inhibitor (NNRTI) (OR 1.74; 95% CI 1.04-2.91 versus LPV/r plus only NRTIs; P = 0.04) showed a higher risk of LPV/r discontinuation by a Cox analysis, whereas non-intravenous drug abusers (IVDUs) (OR 0.40; 95% CI 0.24-0.67 versus IVDUs; P = 0.001) had a lower risk. The rate of discontinuation for toxicity decreased by 17% for each additional month of LPV/r exposure (OR 0.83; 95% CI 0.80-0.86 for each additional month; P < 0.001). LPV/r was substantially well tolerated. Diarrhoea was the most frequent adverse event leading to discontinuation. HCV-HIV co-infected patients and patients with a short exposure to LPV/r have a higher risk of discontinuing LPV/r and should be strictly monitored.

Use of lopinavir/ritonavir in HIV-infected patients failing a first-line protease-inhibitor-containing HAART.

OBJECTIVES: The long-term virological efficacy of lopinavir/ritonavir-containing highly active antiretroviral therapy (HAART) in HIV-infected patients failing a first-line protease inhibitor (PI)-based regimen is still unclear. METHODS: An observational study was carried out from December 2000-December 2002 on 111 consecutive patients starting lopinavir/ritonavir. The primary end-point was virological success (HIV RNA <50 copies/mL in two consecutive determinations). CD4 outcome, lipid levels and adverse events were recorded. The Kaplan-Meier method and log-rank test were used to estimate the time-dependent probability of reaching the end-point using intention-to-treat and on-treatment approaches. RESULTS: Ninety-six patients obtained virological success during follow-up; Kaplan-Meier analysis showed that the time-dependent probability of obtaining this end-point was 78.4% at month 12 and 85.8% at month 24. The median CD4+cell count increased by 118 cells/mm(3) from baseline to month 12 and by 153 cells/mm(3) to month 24. Thirty-one patients discontinued lopinavir/ritonavir: 16 because of drug-related toxicities, six for simplification, five because of virological failure, one patient was lost at follow-up and three died. An elevation in lipid parameters was observed, but only a minority of patients developed a grade 3 or higher hypertriglyceridaemia and/or hypercholesterolaemia. Among the 15 patients not reaching virological success, five had < or =5 mutations in the protease region known to reduce susceptibility to lopinavir/ritonavir (one discontinued lopinavir/ritonavir because of gastrointestinal intolerance), five had no mutations (two discontinued lopinavir/ritonavir because of gastrointestinal intolerance) and five showed > or =6 mutations (all discontinued lopinavir/ritonavir); however, of the patients who discontinued lopinavir/ritonavir none achieved HIV RNA <50 copies/mL on subsequent regimens. CONCLUSIONS: Lopinavir/ritonavir was highly effective and well tolerated in HIV-infected patients failing a first-line PI-based HAART.

Monitoring of human cytomegalovirus (HCMV)-specific CD4+ T cell frequency by cytokine flow cytometry as a possible indicator for discontinuation of HCMV secondary prophylaxis in HAART-treated AIDS patients.

OBJECTIVE: Absolute CD4+ T cell count and human cytomegalovirus (HCMV)-specific CD4+ T cell frequency (as determined by cytokine flow cytometry, CFC) were compared for their ability to predict HCMV disease and safe discontinuation of HCMV secondary prophylaxis. STUDY DESIGN: Three groups of AIDS patients with previous nadir CD4+ T cell count <100/microl were studied. Group A included 48 HAART-treated patients with no HCMV disease. Group B included 11 HAART-treated patients with previous HCMV disease who discontinued HCMV prophylaxis. Group C included 23 HAART-treated (n = 16) or -naive (n = 7) patients with previous HCMV disease either continuing or starting HCMV prophylaxis. Patients underwent follow-up for detection of HCMV viremia or disease (groups A and B) and for discontinuation of HCMV secondary prophylaxis on the basis of either HCMV-specific or absolute CD4+ T cell count (group C). RESULTS: During follow-up, while some patients showed a stable HCMV-specific CD4+ T cell response, others had a fluctuating response (unstable responders) or showed no response at all. In detail, 13/48 group A patients were either HCMV non-responders or unstable responders and 2 of them developed HCMV viremia; 3/11 group B patients were unstable responders, none developing either HCMV viremia or disease; finally, 9 group C patients discontinued HCMV prophylaxis based on absolute CD4+ T cell count > 150 cells/microl, but in 2 of them lacking HCMV-specific response HCMV retinitis relapsed. None of the seven group C patients discontinuing HCMV prophylaxis on the basis of CFC showed HCMV disease relapse. CONCLUSIONS: CFC may support absolute CD4+ T cell count for both guiding HCMV prophylaxis discontinuation and better monitoring HCMV infection in AIDS patients with no previous HCMV disease or having discontinued HCMV prophylaxis.

Virological success of lopinavir/ritonavir salvage regimen is affected by an increasing number of lopinavir/ritonavir-related mutations.

We evaluated the virological outcome of lopinavir/ritonavir (LPV/RTV) in 224 HIV-1-infected and protease inhibitor (PI)-experienced patients showing virological failure to a highly active antiretroviral therapy (HAART) regimen and followed up for at least 3 months. At baseline, the median level of plasma viraemia was 4.61 log10 copies/ml (range 3-6.48) and the median CD4 cell count was 219 cells/mm3 (range 1-836). During a median follow-up of 272 days (range 92-635), we observed an increase in the number of CD4 cells (P=0.02) and a dramatic decrease in plasma viraemia levels (P=0.0001), which became undetectable in 122 patients (54.5%). The closely related predictive factors were baseline plasma viraemia levels and the number of mutations known to reduce susceptibility to LPV/RTV. Thirty-one patients (13.8%) discontinued LPV/RTV during the follow-up, and one AIDS event and three deaths were recorded. Of the 134 patients (59.8%) who underwent a baseline genotype resistance test, 22 (16.4%) had > or = 6 mutations known to reduce LPV/RTV susceptibility; plasma viraemia became undetectable in 76 patients (56.7%), only five of whom harboured > or = 6 mutations at baseline (P=0.0001). The independent predictive factors related to virological success were plasma viraemia levels and the number of mutations reducing susceptibility to LPV/RTV at baseline; each additional log10 copies/ml of HIV RNA reduced the probability of virological success by 34.0% and each extra mutation by 14.5%.