Biliodigestive fistulae and gallstone ileus: diagnostic and therapeutic considerations. Our experience.

The biliodigestive fistula is not a rare affection in the context of acute pathology of the gastrointestinal tract. It often affects patients between 63 and 85 years old , particularly the female sex, and the most common cause is acute or chronic cholecystolithiasis. Open issues are the delayed in the pre-operative diagnosis, and controversies exist regarding the best surgical approach. The choice of treatment options is influenced by the age of the patients and their clinical conditions and also by the presence of comorbidities and of a delayed right diagnosis. In the 1 to 3% of cases, the biliodigestive fistula presents a gallstone ileus as complication, whose diagnosis is particularly difficult for the lack of specific signs and symptoms. The contrast-enhanced CT is considered the gold standard for a specific pre-operative diagnosis, as it directly shows the fistula. Surgical treatments include one-stage procedure or two-stage procedure. Many studies seem to favor a deferred definitive procedure. The Authors describe 4 cases: in 3 cases, women between 70 and 80 years old presenting an history of recurrent cholecystitis, in 2 cases, and in 1 case presenting a bowel obstruction; in 1 case a 50-years-old man, with no significant past medical history, presenting a bowel obstruction. The Authors have performed in the 2 cases of gallstone ileus an enterolithotomy with cholecysto-duodenal fistula repair and cholecystectomy, in one-stage, and this has been possible because of the good clinical conditions of the patients and their low operative risk. In the case of fistula without the complication of gallstone ileus, the treatment approach has been cholecysto-gastric fistula closure with a gastroplastic using separate stitches and cholecystectomy, in one-stage. We are in agreement with data in the literature regarding the delay into the diagnosis of biliodigestive fistula and with the importance to suspect it or gallstone ileus presence, although the clinical presentation is extremely non-specific. In our experience, cholangiopancreatography-CT and CECT have made easier the pre-operative diagnosis and so reducing the delay of the treatment.

Small bowel intussussception due to metastatic melanoma of unknown primary site. Case report.

Malignant melanoma is characterized by metastases also to the gastrointestinal tract, especially in the small bowel. The diagnosis is often delayed because unspecific clinical presentation (frequently as chronic iron deficiency anemia, rectal bleeding or intestinal obstruction). We present a case of melanoma of unknown primary site, with clinical presentation of intestinal obstruction. A segmental resection of the ileum was performed including mesentery with lymph nodes. Histology revealed metastatic melanoma from unknown primary. PET and MRI confirmed disseminated disease without brain metastasis.

Risk management in surgery.

Malpractice is the responsible for the greatest number of legal claims. At the present time, legal actions against physicians in Italy are 15,000 per year, and a stunning increase about costs to refund patients injured by therapeutic and diagnostic errors is expected. The method for the medical prevention is "Risk Management", that is the setting-up of organizational instruments, methods and actions that enable the measurement or estimation of medical risk; it allows to develop strategies to govern and reduce medical error. In the present work, the reconstruction about the history of risk management in Italy was carried out. After then the latest initiatives undertaken by Italy about the issue of risk management were examined.

Single-incision laparoscopic appendectomy is comparable to conventional laparoscopic and laparotomic appendectomy: our single center single surgeon experience.

Several studies have demonstrated the clinical and technical benefits of the laparoscopic surgery for complicated and uncomplicated appendicitis. Our retrospective study included 12 patient who underwent SILS appendectomy (SILS-A), 14 who received conventional laparoscopic surgery (VL-A), and 12 who received laparotomic appendectomy (OA); performed in all cases by the same surgeon (C.F.). The aim of this study was the comparison between this three different surgical techniques on same features: post operative leukocytosis, post operative pain, need abdominal drainage, esthetic viewpoint, incidence of complication, hospital stay. The results showed no significant differences between SILS-A and VLS-A, while an evident improvement shows versus O-A, even though not statistically significative. SILS was more effective in decreasing the risk of postoperative wound infection.

Technique and outcomes about a new laparoscopic procedure: the Pelvic Organ Prolapse Suspension (POPS).

Pelvic organ prolapse suspension (POPS) is a recent surgical procedure for one-stage treatment of multiorgan female pelvic prolapse. This study evaluates the preliminary results of laparoscopic POPS in 54 women with a mean age of 55.2 and a BMI of 28.3. Patients underwent at the same time stapled transanal rectal resection (STARR) to correct the residual rectal prolapse. We had no relapses and the preliminary results were excellent. We evaluated the patients after 1 year follow-up and we confirmed the validity of our treatment. The technique is simpler than traditional treatments with an important reduction or completely disappearance of the pre-operative symptomatology.

Undifferentiated connective tissue disease - an unsolved problem:revision of literature and case studies.

In clinical practice, patients with a range of signs and symptoms suggestive of connective tissue disease, but who do not fulfil the classification criteria for a defined disease are often found. This condition is defined as, Undifferentiated Connective Tissue Disease (UCTD). Most of the authors consider UCTD as a distinct clinical entity, generally stable during follow-up. Despite this, no mutual agreement regarding criteria for its diagnosis has been reached. The clinical, serological, therapeutical and evolutional patterns of 41 patients initially diagnosed as having early UCTD during a 3-year followup are described in this study. At the end of the observational period, 21 percent of the enrolled patients, followed throughout the follow-up, demonstrated clinical evolution to a defined connective tissue disease (CTD), whereas 52 percent of the observed subjects maintained an undifferentiated profile with variable clinical findings and presenting a generally stable disease over time. The remaining patients showed clinical improvement or complete regression of the symptoms associated with normalization of the inflammatory indexes. The role of therapy in these different clinical courses is discussed.

[Health care and infective aspects in patients affected by common variable immunodeficiency assisted in the Lazio Regional Authority Reference Centre for Primary Immunodeficiencies]. / Aspetti infettivologici ed assistenziali di pazienti con Immunodeficienza Comune Variabile afferenti al Centro di Riferimento della Regione Lazio per le Immunodeficienze Primitive.

Common variable immunodeficiency (CVID) is a chronic condition characterised by a predominant defect of humoral immunity. In most cases the diagnosis of CVID is made during adulthood; the main clinical features of CVID are chronic and relapsing infections (mainly of respiratory and gastroenteric tracts). CVID patients may also develop neoplastic and autoimmune diseases. In our centre (the Regional Centre for Primary Immunodeficiencies of the Lazio Regional Authority) we administered a 23-item questionnaire to 60 patients with CVID undergoing substitutive therapy with intravenous immunoglobulins (IVIG) about their demographic characteristics, time of clinical onset, time of diagnosis of CVID, clinical features, IVIG doses and administration intervals, and self-assessment of health status. In addition, the clinical history of all patients was reviewed, and the levels of serum IgG, IgA and IgM were evaluated and compared with the pre-therapy serum concentration. Moreover, an analysis of the treatment costs was performed. At onset, 67.2% of patients presented recurrent respiratory infections, and 50% had infections of the lower respiratory tract; 39.6% of the patients had gastroenteric infections. Most patients (57%) had recurrent infections of at least 2 of the respiratory, gastroenteric and/or urogenital tracts. In 37.9% of the group the diagnosis of CVID was made in less than 2 years after the beginning of symptoms, but in many cases (22.4%) the diagnosis took more than 10 years. 93% of patients are treated with a dose of IVIG between 6 and 15 g per administration, with intervals between 2 and 3 weeks. The review of patients'clinical history showed that 43% of patients have had respiratory infections during the follow-up in our Centre, 43% have splenomegaly (3% were also subjected to splenectomy) and 18.3% have autoimmune diseases. The mean concentration of IgG before the beginning of IVIG therapy was 235 mg/dl, while during the follow-up it was 664 mg/dl. Given the long time often required for diagnosis, general physicians and specialists should be better informed in order to make diagnosis swifter. The substitutive therapy with IVIG is effective in preventing recurrent infections and complications. A thorough follow-up is important for diagnosing neoplastic and autoimmune complications; in addition, immunologic analysis of peripheral blood and bone marrow are useful in identifying subgroups of patients with more severe clinical features. Finally, in selected patients, treatment costs may be controlled by modifying the dosage of IVIG or the intervals between administrations.

Effects of nandrolone decanoate compared with placebo or testosterone on HIV-associated wasting.

Objectives Current research is unclear about the most effective pharmacological agents for managing the loss of weight and fat-free mass common in HIV/AIDS. The aim of this study was to compare nandrolone decanoate with placebo and testosterone. Methods The study was a multicentre randomized double-blind placebo-controlled trial. Three hundred and three adult HIV-positive male patients with a weight loss of 5-15% in the last 12 months, or a body mass index of 17-19 kg/m(2), or a body cell mass/height ratio lower than 13.5 kg/m, were randomly assigned to receive nandrolone decanoate (150 mg), testosterone (250 mg) or placebo intramuscularly every 2 weeks for 12 weeks. Fat-free mass, weight, immune markers and perception of treatment were the main outcome measures. Results Treatment with nandrolone resulted in significantly greater increases in fat-free mass [mean increase 1.34 kg; 95% confidence interval (CI) 0.60; 2.08 kg] and in weight (mean increase 1.48 kg; 95% CI 0.82; 2.14 kg) compared with placebo. The mean increase in weight with nandrolone of 1.00 kg (95% CI 0.27; 1.74 kg) when compared with testosterone was significant, although the difference in fat free mass did not reach significance (mean increase 0.69 kg; 95% CI-0.13; 1.51 kg). Patient perception of benefit was significantly greater in the nandrolone group when compared with both the placebo and the testosterone groups. Conclusions Treatment with nandrolone decanoate increased body weight when compared with placebo and testosterone. Nandrolone decanoate treatment resulted in greater increases in fat-free mass than placebo and demonstrated a trend for a significant increase when compared with testosterone.

Lymphomononuclear cells from multiple sclerosis patients spontaneously produce high levels of oncostatin M, tumor necrosis factors alpha and beta, and interferon gamma.

Proinflammatory cytokines are deemed to play a pivotal role in the pathogenesis of multiple sderosis (MS). They provide signals for T-cell activation and inflammatory cell recruitment in the brain and might directly alter neuroglial and neuronal cell survival and function. We found that peripheral blood mononuclear cells (PBMCs) from MS patents spontaneously produce high levels of TNFalpha, TNFbeta, IFNgamma, and oncostatin M (oncM), a proinflammatory cytokine actng on cells of neural, vascular, hematopoietic, and lymphoid origin. Spontaneous production of these cytokines was significantly higher (p < 0.01) in PBMC short-term culture supernatants from MS patients than in blood donors (HC). On average, lectin-induced production of these cytokines by PBMC was higher in MS patents than in HC significantly so only for TNFalpha (p = 0.013). Determination of TNFalpha, TNFbeta IFNgamma, and oncM in corresponding sera showed that on average, oncM levels were higher in MS patients than in HC, though the results were not statistically significant whereas levels of TNFalpha, TNFbeta and IFNgamma were below the assay threshold in most patients. The finding that MS PBMCs are primed in vivo to produce and release high levels of proinflammatory cytokines suggests the presence of a basal activation of the immune system which, in turn, may play a role in the complex circuitry of molecular and cellular interactions responsible for neurologic damage in MS.

Assessment of thymic output in common variable immunodeficiency patients by evaluation of T cell receptor excision circles.

Common variable immunodeficiency (CVID) is a heterogeneous syndrome characterized by repeated infections and hypogammaglobulinaemia. Additionally, T-cell abnormalities including lymphopenia, decreased proliferation to mitogens and antigens, and the reduced production and expression of cytokines, have also been observed. In this study we have investigated the expression of naive, memory and activation markers in T-cell subpopulations in 17 CVID patients in comparison to age-matched normal controls. The numbers of CD4+ T cells, including CD45RA+CD62L+ and, to a lesser extent, CD45RA-CD62L+/RA+CD62L- were significantly reduced in patients, whereas CD8+ T cells were within normal range. In contrast, HLA-DR+ cells were increased both in CD4+ and CD8+ T cells. To assess the thymic output, we analysed the presence of T-cell receptor excision circles (TRECs) in CD4+ and CD8+ T cells by quantitative PCR. TRECs were decreased significantly in patients and the rate of TREC loss was higher with increasing age. TRECs correlated with naive CD4+ T cells, whereas there was an inverse relationship between TRECs and CD8+HLA-DR+ and CD8+CD45RA-CD62L+/RA+CD62L- T cells. Our results suggest the presence of a defect in the naive T cell compartment with origin at the thymic level in CVID, and indicate that TREC may be a useful marker to monitor thymic function in this primary immunodeficiency.

Endogenous cytokine production protects T cells from spontaneous apoptosis during highly active antiretroviral therapy.

BACKGROUND: The availability of therapeutic regimens that effectively interfere with HIV-1 replication provides novel opportunities to investigate mechanisms of T-cell depletion as well as repopulation in infected individuals. METHODS: Nineteen HIV-1-infected individuals were investigated during one-year follow-up of highly active retroviral therapy (HAART). The frequencies of apoptotic T cells, as determined by propidium iodide, staining, TUNEL assay and analysis of annexin V, were assessed either in the absence or in the presence of anti-interleukin (IL)2 and anti-IL-4 neutralizing Ab. Spontaneous and lectin-induced cytokine production were assessed by ELISA. RESULTS: Increments of both naive and memory CD4 and CD8 T cells during HAART are accompanied by a decrease of T-cell apoptosis that, after 12 months of HAART, reaches normal levels. This is associated with increments of both spontaneous and activation-induced production of IL-2 and IL-4 by peripheral blood mononuclear cells (PBMCs), though only the latter was found defective at enrolment. During HAART, blocking of either IL-2 or IL-4 production by PBMCs using neutralizing Ab restores levels of T-cell apoptosis consistent with those determined at enrolment. These data suggest that both IL-2 and IL-4 produced by PBMCs during HAART provide anti-apoptotic signals that can contribute to an increased survival of T cells and may thus play a part in long-term immune reconstitution. CONCLUSIONS: An effective viral suppression and, possibly, effects of PI on molecular targets other than viral components, can support a progressive normalization of T-cell survival that, at least in part, depends upon the restoration of proper soluble signals. These results provide evidence of a supporting role of endogenous cytokine production in peripheral T-cell repopulation during an effective and prolonged viral suppression. This may be relevant for the definition of immune-intervention targets aimed at immune reconstitution in HIV-1-infected patients.

Spreading of HIV-specific CD8+ T-cell repertoire in long-term nonprogressors and its role in the control of viral load and disease activity.

Long-term non-progressors (LTNP) represent a minority of human immunodeficiency virus (HIV) infected individuals characterized by stable or even increasing CD4+ T-cell count and by stronger immune responses against HIV than progressors. In this study, HIV-specific effector CD8+ T cells, as detected by both a sensitive ex vivo enzyme-linked immunospot (ELISPOT) assay and specific major histocompatibility complex (MHC) peptide tetramers, were at a low frequency in the peripheral blood of LTNP, and recognized a lower number of HIV peptides than their memory resting cell counterparts. Both factors may account for the lack of complete HIV clearance by LTNP, who could control the viral spread, and displayed a higher magnitude of cytotoxic T lymphocyte (CTL) responses than progressors. By combining cell purification and ELISPOT assays this study demonstrates that both effector and memory resting cells were confined to a CD8+ population with memory CD45RO+ phenotype, with the former being CD28- and the latter CD28+. Longitudinal studies highlighted a relatively stable HIV-specific effector repertoire, viremia, and CD4+ T-cell counts, which were all correlated with maintenance of nonprogressor status. In conclusion, the analysis of HIV-specific cellular responses in these individuals may help define clear correlates of protective immunity in HIV infection.

Impaired nutritional status in common variable immunodeficiency patients correlates with reduced levels of serum IgA and of circulating CD4+ T lymphocytes.

BACKGROUND: Common variable immunodeficiency (CVI) is a primary defect of the immune system. Infections, persistent diarrhoea and malabsorption may result in malnutrition, which may in turn contribute to increased morbidity. In this paper, the prevalence of malnutrition in CVI was evaluated. PATIENTS AND METHODS: Forty CVI patients (20 male, 20 female, aged 17-75 years) underwent anthropometric measurements from which body mass index, arm fat and muscle area were calculated. Body mass index values < 18.5 and arm fat and muscle area values < 10th percentile were considered indicative of malnutrition. Patients were divided into four groups according to circulating CD4+ T cells (lower or greater than 300 microL(-1)) and serum immunoglobulin A (IgA) levels (detectable and undetectable). RESULTS: Body mass index < 18.5, arm fat and muscle area < 10th percentile were observed in 23%, 58% and 44%, respectively, of patients. Lower values of body mass index, arm fat and muscle area were more frequent in patients with low CD4+ cells and undetectable IgA. Low arm fat values were more frequent in patients with diarrhoea (P = 0.03). Infectious episodes were more frequent in undetectable IgA than in detectable IgA patients (P = 0.04). CONCLUSIONS: Anthropometric measurements revealed an increased rate of malnutrition in CVI patients, particularly in those with low CD4+ and undetectable IgA, suggesting that selected CVI subjects could be considered for standard or specialized nutritional support.

T-Cell immune activation in children with vertically transmitted hepatitis C virus infection.

Little is known concerning the clinical features, the histological outcome, and the effects on the maturation of immune system of children with vertically-transmitted hepatitis C virus (HCV) infection. Specifically, no data are available on the peripheral distribution of T-cell subsets. The frequency of naive and memory cells, activated T cells, and cytokine-producing T cells was analyzed in nine HCV-infected children born to HCV-positive mothers. In HCV-infected children, the distribution of naive and memory cells was not significantly altered in the CD4 subset whereas within the CD8 subset, an increase of memory and a decrease of naive cells was observed. The frequency of HLA-DR-positive and Fas-positive T cells was increased in HCV-infected children in both CD4 and CD8 subsets. The distribution of Fas-expressing T cells was directly related to that of HLA-DR cells and inversely related to the frequency of naive T cells. In regard with cytokine production we found increased levels of both CD4 and CD8 interferon-gamma (IFN-gamma)-producing cells whereas no difference in the percentage of interleukin-2 (IL-2)-producing T cells was observed. No meaningful correlation was observed between individual T cell subsets and ALT levels or HCV viral load. In conclusion, our results indicate an increased T-cell activation and a shift to a T(H)1 pattern of cytokine production in children with vertically transmitted HCV infection. The cause of this kind of immune response could reside in the persistent antigenic stimulation by chronic HCV infection.

T cell responses to highly active antiretroviral therapy defined by chemokine receptors expression, cytokine production, T cell receptor repertoire and anti-HIV T-lymphocyte activity.

The immunological correlates of highly active antiretroviral therapy (HAART)-induced suppression of human immunodeficiency virus type 1 (HIV-1) replication have been investigated. 20 HIV-1-infected patients with mean CD4+ T cell count of 298/microl, plasma viral load of 4.7 log10 copies/ml and naive for protease inhibitors (PI) were studied during12 months of HAART. An increased number of both CD4+ and CD8+ naive T cells and a normalization of the frequency of CCR5- and CXCR4-expressing CD4+ T cells were readily observed after starting therapy. Single cell analysis of cytokine production after 12 months of HAART showed an increased number of interleukin (IL)-2-, but not IL-4- and (IFN)-gamma-, producing T cells and a decreased percentage of CD8+ IFN-gamma + cells. A correlation between the frequency of IFN-gamma-producing T cells and that of memory, CCR5+ and CD95+ T cells was demonstrated in both CD4+ and CD8+ subsets. The diversity of T cell receptor (TCR) variable beta (BV) chain repertoire significantly increased after 12 months of HAART within the CD4+ but not the CD8+ T cell subset. However, the level of perturbation of the third complementarity-determining region (CDR3), was not significantly modified by effective therapy. The number of anti-HIV Gag and Pol cytotoxic T lymphocytes precursors (CTLp) decreased during HAART and highly correlated with the CD8 IFN-gamma response. Ameliorated clinical conditions were observed in all patients in absence of any opportunistic infections during all the study period. These observations indicate that a better restoration of immunity may be obtained in patients starting HAART at less advanced stages of the disease.

Distribution of the natural killer-related receptor for HLA-C during highly active antiretroviral therapy for human immunodeficiency virus infection.

Receptors interacting with Major Histocompatibility Complex class I molecules have been initially found on the surface of human natural killer (NK) cells, where they deliver inhibitory signals to the lysis, being thus defined killer inhibitory receptors (KIR). Subsequently, they were detected also on the surface of T-CD8(+) lymphocytes and are particularly expanded during human immunodeficiency virus (HIV) infection, where they downregulate HIV-specific cytolysis. The expression of KIR recognizing human leukocyte antigen-C alleles was assessed in HIV-infected patients, undergoing highly active antiretroviral therapy (HAART). To this end, the combined expression of CD16/CD56, of CD3 and CD8 as well as of KIR (CD158a and CD158b) surface molecules was analyzed on peripheral blood mononuclear cells by monoclonal antibodies, and flow cytometry. An increase of CD3(+)CD8(+)CD158b(+) cells was found after 6 months of HAART. This finding may have implications for the regulation of T-cell mediated cytolysis during HAART.

A randomized trial comparing the introduction of ritonavir or indinavir in 1251 nucleoside-experienced patients with advanced HIV infection.

ISS-IP1, a multicenter, randomized, 48-week open trial, was designed to compare the introduction of ritonavir or indinavir in patients with previous nucleoside experience and CD4+ cell counts below 50/mm3. Concomitant antiretroviral treatment with nucleoside analogs was allowed. Primary efficacy measures were survival and time to a new AIDS-defining event or death, analyzed through the whole period of observation by the intention-to-treat approach. Primary toxicity measures were time to treatment discontinuation and adverse events, grade at least 3/serious, analyzed by an on-treatment approach. Evaluation-of efficacy also included CD4+ cell and RNA response. The trial enrolled 1251 patients in 5 months. At baseline, mean CD4+ cell count was about 20 cells/mm3 and mean HIV RNA copy number was 4.9 log10/ml in both groups. Overall, 402 patients in the ritonavir group and 250 patients in the indinavir group permanently discontinued the assigned treatment (relative risk, 1.96; 95% CI, 1.68-2.30; p = 0.0001), with most of this difference dependent on a higher number of discontinuation for adverse events in the ritonavir group. After a mean follow-up of 307 days (ritonavir, 304; indinavir, 309), 124 deaths (ritonavir, 61; indinavir, 63; relative risk, 0.96; 95% CI, 0.67-1.36; p = 0.80) and 330 new AIDS-defining events (ritonavir, 170; indinavir, 160; relative risk, 1.05; 95% CI, 0.85-1.31; p = 0.60) were observed. CD4+ cell counts increased in both groups in patients still receiving treatment, with about 100 cells gained by week 24 and 150 cells gained by week 48. Body weight also increased over time in both groups. Analysis of RNA response showed a decrease of 1.5 log10 or higher in both treatment groups. Overall, 400 patients in the ritonavir group and 338 patients in the indinavir group developed at least one grade 3/serious new adverse event during follow-up (relative risk, 1.48; 95% CI, 1.28-1.72; p = 0.0001). Favorable CD4+ cell and RNA responses at 24 and 48 weeks were observed in both groups of patients remaining on treatment. Indinavir showed slightly better effects in sustaining RNA, CD4+ cell, and body weight responses. Ritonavir and indinavir results were comparable in terms of clinical outcome (survival and AIDS-defining events).

Role of immune-derived diffusible mediators in AIDS-associated neurological disorders.

Neurologic abnormalities are common in HIV-1 infected patients and often represent the dominant clinical manifestation of pediatric AIDS. Although the neurological dysfunction has been directly related to CNS invasion by HIV-1, the pathogenesis of neurologic disorders remains unclear. This review will first discuss the spectrum of potential interactions between HIV-1 and neural (neuronal and glial) cells, in the face of experimental data. Next, we will focus on the role of immune-derived cytokines and other soluble compounds which have been proposed to act as neurotoxic mediators and appear to play a role in the pathogenesis of AIDS-associated neurodegeneration.

Recovery of hematopoietic activity in bone marrow from human immunodeficiency virus type 1-infected patients during highly active antiretroviral therapy.

The mechanisms responsible for the hematopoietic failure in human immunodeficiency virus type 1 (HIV-1)-infected patients are still unknown. Several findings indicate that the in vitro proliferative potential of precursor cells from AIDS patients is reduced. The changes seen in bone marrow (BM) morphology and the defective BM functions associated with cytopenias have both been proposed as potential explanations. In patients treated with highly active antiretroviral therapy (HAART) an immune reconstitution associated with increased whole blood cell counts has been described. We have investigated the effects of HAART on the number of colony-forming cells (CFCs) and long-term culture-initiating cells (LTC-ICs), using long-term BM cell cultures (LTBMC) in a group of subjects with HIV-1 infection enrolled in an open study to evaluate the mechanisms of immune reconstitution during HAART. In each patient, the increase in colony growth was homogeneous, regardless of the type of hematopoietic progenitor cells assayed; in four subjects an increase in the most primitive progenitor cells (LTC-ICs) was observed. These findings were associated with the in vivo data showing increased numbers of BM mononuclear cells (BMMCs) after HAART and with a rise in peripheral CD4(+) T cell counts and decreased levels of plasma HIV-1 RNA. A decreased number of hematopoietic progenitor cells and/or a defective modulation of progenitor cell growth might be the cause of the hematological abnormalities in AIDS patients. Controlling HIV-1 replication by HAART could determine a restoration of stem cell activity, probably because of the suppression of factors that inhibit normal hematopoiesis.