Altered functional connectivity of the subthalamus and the bed nucleus of the stria terminalis in obsessive-compulsive disorder

BACKGROUND

The assessment of inter-regional functional connectivity (FC) has allowed for the description of the putative mechanism of action of treatments such as deep brain stimulation (DBS) of the nucleus accumbens in patients with obsessive-compulsive disorder (OCD). Nevertheless, the possible FC alterations of other clinically-effective DBS targets have not been explored. Here we evaluated the FC patterns of the subthalamic nucleus (STN) and the bed nucleus of the stria terminalis (BNST) in patients with OCD, as well as their association with symptom severity.

METHODS

Eighty-six patients with OCD and 104 healthy participants were recruited. A resting-state image was acquired for each participant and a seed-based analysis focused on our two regions of interest was performed using statistical parametric mapping software (SPM8). Between-group differences in FC patterns were assessed with two-sample t test models, while the association between symptom severity and FC patterns was assessed with multiple regression analyses.

RESULTS

In comparison with controls, patients with OCD showed: (1) increased FC between the left STN and the right pre-motor cortex, (2) decreased FC between the right STN and the lenticular nuclei, and (3) increased FC between the left BNST and the right frontopolar cortex. Multiple regression analyses revealed a negative association between clinical severity and FC between the right STN and lenticular nucleus.

CONCLUSIONS

This study provides a neurobiological framework to understand the mechanism of action of DBS on the STN and the BNST, which seems to involve brain circuits related with motor response inhibition and anxiety control, respectively.

Brain structural correlates of obsessive-compulsive disorder with and without preceding stressful life events

Objectives There is growing evidence supporting a role for stressful life events (SLEs) at obsessive-compulsive disorder (OCD) onset, but neurobiological correlates of such effect are not known. We evaluated regional grey matter (GM) changes associated with the presence/absence of SLEs at OCD onset. Methods One hundred and twenty-four OCD patients and 112 healthy controls were recruited. Patients were split into two groups according to the presence (n = 56) or absence (n = 68) of SLEs at disorder's onset. A structural magnetic resonance image was acquired for each participant and pre-processed with Statistical Parametric Mapping software (SPM8) to obtain a volume-modulated GM map. Between-group differences in sociodemographic, clinical and whole-brain regional GM volumes were assessed. Results SLEs were associated with female sex, later age at disorder's onset, more contamination/cleaning and less hoarding symptoms. In comparison with controls, patients without SLEs showed GM volume increases in bilateral dorsal putamen and the central tegmental tract of the brainstem. By contrast, patients with SLEs showed specific GM volume increases in the right anterior cerebellum. Conclusions Our findings support the idea that neuroanatomical alterations of OCD patients partially depend on the presence of SLEs at disorder's onset.

Brain regions related to fear extinction in obsessive-compulsive disorder and its relation to exposure therapy outcome: a morphometric study

BACKGROUND

The size of particular sub-regions within the ventromedial prefrontal cortex (vmPFC) has been associated with fear extinction in humans. Exposure therapy is a form of extinction learning widely used in the treatment of obsessive-compulsive disorder (OCD). Here we investigated the relationship between morphometric measurements of different sub-regions of the vmPFC and exposure therapy outcome in OCD.

METHOD

A total of 74 OCD patients and 86 healthy controls underwent magnetic resonance imaging (MRI). Cortical thickness and volumetric measurements were obtained for the rostral anterior cingulate cortex (rACC), the medial orbital frontal cortex and the subcallosal cortex. After MRI acquisition, patients were enrolled in an exposure therapy protocol, and we assessed the relationship between MRI-derived measurements and treatment outcome. Baseline between-group differences for such measurements were also assessed.

RESULTS

Compared with healthy controls, OCD patients showed a thinner left rACC (p = 0.008). Also, left rACC thickness was inversely associated with exposure therapy outcome (r - 0.32, p = 0.008), and this region was significantly thinner in OCD patients who responded to exposure therapy than in those who did not (p = 0.006). Analyses based on regional volumetry did not yield any significant results.

CONCLUSIONS

OCD patients showed cortical thickness reductions in the left rACC, and these alterations were related to exposure therapy outcome. The precise characterization of neuroimaging predictors of treatment response derived from the study of the brain areas involved in fear extinction may optimize exposure therapy planning in OCD and other anxiety disorders.

Interaction of SLC1A1 gene variants and life stress on pharmacological resistance in obsessive-compulsive disorder

Genetic and environmental factors seem to interact and influence both the onset and the course of obsessive-compulsive disorder (OCD), but the role of glutamate transporter variants (SLC1A1) in pharmacological resistance is not known. We aimed to assess whether genetic variants in SLC1A1 and life stress at onset of the disorder interact and modulate pharmacological resistance in OCD. A single-marker association study of several single-nucleotide polymorphisms in the SLC1A1 genomic region was performed in a sample of 238 OCD patients. For the most strongly associated SNP (rs3087879), one copy of the risk allele increased the probability of higher treatment resistance (odds ratio=2.42; 95% confidence interval=1.39-4.21; P=0.0018), but only in OCD patients without life stress at onset of the disorder. These results suggest a gene-by-environment interaction effect on treatment resistance in OCD and strengthen the existing evidence of the role of the glutamatergic system in the phenomenology of OCD.

Allogeneic stem cell transplantation with reduced-intensity conditioning is potentially feasible as an outpatient procedure

Allogeneic stem cell transplantation (allo-SCT) after a reduced-intensity conditioning (RIC) protocol is associated with decreased short-term toxicity. This suggests that the procedure could be performed on an outpatient basis. We analysed the incidence and risk factors of grade >or=2 conditioning-related toxicities (CRTs) as a hallmark for hospital admission, in 41 consecutive patients allografted from an HLA identical sibling after RIC. The RIC regimen consisted of fludarabine plus melphalan for lymphoid malignancies, and fludarabine plus busulphan for myeloid malignancies. In all, 11 patients (27%) did not experience any toxicity. The more frequent CRTs observed were neutropenic fever and gastrointestinal toxicity. The median duration of hospitalisation was 27 (range, 17-50) days. If allo-SCT had been planned as an outpatient procedure and admission indicated only in the case of >or=2 CRTs, the inpatient period would have decreased to 9 (range, 0-33) days (P<0.001). No risk factors for CRTs were identified. Allo-SCT after an RIC regimen is a well-tolerated procedure. Our results warrant a prospective pilot trial of nonmyeloablative allo-SCT performed in the outpatient setting.

Clinical applicability of the new EORTC/MSG classification for invasive pulmonary aspergillosis in patients with hematological malignancies and autopsy-confirmed invasive aspergillosis

Diagnosis of invasive pulmonary aspergillosis (IPA) is often difficult. Recently, the European Organization for Research and Treatment of Cancer/Mycoses Study Group (EORTC/MSG) has proposed new criteria for the classification of invasive fungal infections. We have studied the clinical applicability of this classification in 22 patients with hematological malignancies who had IPA at autopsy. While alive, according to the EORTC/MSG criteria, only 2 patients were classified as having proven IPA, 6 as probable, 13 as possible, and 1 was unclassifiable. Of the patients, 64% had no microbiological or major clinical criteria before death. Although the EORTC/MSG criteria are an important step forward in the standardization of definitions used for IPA in clinical research studies, most patients who die with extensive lung disease only reach a level of possible or probable IPA during life, further highlighting that these guidelines should not be used for clinical decision-making.

Invasive fungal infections in hematology: new trends

Invasive fungal infections (IFI) are among the most feared complications of patients being treated for a hematological malignancy. Currently, most serious IFI occur in patients with acute leukemia and after allogeneic hematopoietic stem cell transplantation. Although Candida albicans and Aspergillusspp. continue to be the main pathogens, the proportion of patients infected by non-albicans species of Candida and other yeasts and by other filamentous fungi is rising in most institutions. Risk factors for the various IFI differ, and it is thus of utmost importance to realize that not all patients are the same with respect to the risk for developing the various IFI. Recent advances in diagnosis now allow the use of very sensitive imaging techniques with an extremely low negative predictive value. Among the novel microbiologic methods, the galactomannan antigen test is now commercially available for routine use in the diagnosis of aspergillosis, while DNA fungal detection is still experimental. For the first time, clinicians now have a broad range of antifungals to chose from, with special emphasis on amphotericin B preparations, novel broad-spectrum azoles, and the echinocandins. However, the exact place of these agents in treating different IFI will need to be found in the near future.

Safety and efficacy of low-dose amphotericin B lipid complex for empirical antifungal therapy of neutropenic fever in patients with hematologic malignancies

Amphotericin B lipid complex (ABLC) has been investigated as an empirical antifungal treatment for neutropenic patients with persistent fever of unknown origin (FUO). We studied the safety and efficacy of low dose ABLC (1 mg/kg/day) for empirical treatment of neutropenic FUO. Sixty-one patients with hematologic malignancies developing 69 episodes of neutropenic FUO after chemotherapy or hematopoietic stem cell transplantation were included in the study. The median patient age was 47 years (18-68). The median duration of neutropenia (< 0.5 x 10(9)/l) was 17 days (7-45) and the median duration of ABLC therapy was 8 days (2-19). Thirteen patients (19%) suffered from mild to moderate infusion-related adverse events. Creatinine levels were stable in 42 cases (61%), improved in 9 (13%) and deteriorated in 18 (26%), with no other significant toxicities. Among 67 evaluable episodes, the response rate (resolution of fever during the period of neutropenia without developing a fungal infection) was 67%, while 33% were treatment failures. Low-dose ABLC is safe, well tolerated and seems to be at least as effective as c-AmB for empirical antifungal therapy of FUO. Randomized trials at this dose level comparing ABLC with c-AmB or other lipid formulations are warranted.

Autologous stem cell transplantation for high-risk Hodgkin's disease: improvement over time and impact of conditioning regimen

BACKGROUND AND OBJECTIVE

High-dose chemo/radiotherapy with autologous stem cell support is increasingly being used in Hodgkin's disease (HD) patients who do not respond to or who relapse after conventional chemotherapy. In this work we analyze the results of 56 consecutive high-risk HD patients autografted in our institution and the role of possible prognostic factors.

DESIGN AND METHODS

There were 34 males and 22 females with a median age of 31 years. At transplantation, 24 patients (43%) were in complete remission and 32 (57%) were autografted while with active disease. Twenty-nine patients were autografted before January 1993. Bone marrow was used as the source of stem cells in 40 patients (71%) and peripheral blood (PB) in 16 (29%). Forty-five patients received chemotherapy-based conditioning regimens (40 CBV and 5 BEAM) while the remaining 11 received cyclophosphamide (Cy) and total body irradiation (TBI).

RESULTS

Two bone marrow transplantation (BMT) recipients did not engraft. Hematologic recovery was significantly faster in patients transplanted with PB progenitor cells. Early transplant-related mortality (early TRM) (before day 100 after transplantation) was 9%; it was higher in patients transplanted before January 1993 than in patients transplanted afterwards (14% vs 4%) and in patients receiving TBI (18% vs 7%), although these differences did not reach statistical significance. Overall TRM (before and after day 100) was 14%. TBI-containing regimens significantly increased overall TRM (36% and 9%, p = 0.03). Actuarial 3.5-year overall survival (OS), event-free survival (EFS) and progression-free survival (PFS) were 57%, 58% and 65%, respectively. On multivariable analysis, TBI containing regimens and transplantation before 1993 significantly reduced OS and EFS.

INTERPRETATION AND CONCLUSIONS

Our results confirm that high-dose therapy followed by autologous stem cell transplantation is associated with sustained PFS in a remarkable proportion of patients with HD unlikely to be cured with standard chemotherapy. Results improved over time and TBI containing regimens had a negative effect on post-transplant outcome.

Intensified prophylaxis of febrile neutropenia with ofloxacin plus rifampin during severe short-duration neutropenia in patients with lymphoma

To analyse the impact of intensified prophylaxis with ofloxacin plus rifampin (O+R) in neutropenic patients we used this combination in 40 consecutive cycles of ifosfamide, cytarabine, prednisolone and etoposide (IAPVP-16). This salvage chemotherapy regimen for lymphoma usually produces four to six days of severe neutropenia without significant extrahematologic toxicities. We compared the infectious morbidity during neutropenia under O+R with 58 consecutives cycles using either norfloxacin or no prophylaxis (control group). Fifty-three percent of control group patients and 20% of the O+R group developed febrile neutropenia that required hospital admission (p<0.001, 95% CI for the difference between both proportions of 16% to 51%). Bacteremia was documented in two patients in the O+R group and six in the control group (p=0.08). Gram-positive cocci (GPC) accounted for all six bacteremias in the control group, while both cases in O+R group were due to a quinolone-resistant gram-negative bacteria (GNB) (p<0.01 for GPC). Five patients (13%) who received O+R and 23 (40%) in control group developed fever of unknown origin, p<0.001, while the total duration of hospitalization due to febril neutropenia was 42 days and 158 days, respectively (p<0.001). In conclusion, intensified prophylaxis with O+R appears to reduce the rate of febrile neutropenia and GPC bacteremia in patients with short and severe neutropenia, which translates into a reduction in the need for hospitalization.

Lack of association between venous thrombosis and subsequent malignancy in a retrospective cohort study in young patients

Since the publication of Trousseau in 1865, several studies have documented an increased incidence of cancer in patients with deep venous thrombosis (DVT) especially those with idiopathic or recurrent DVT, but in young patients this association is not clear and is therefore a subject of controversy. We performed a retrospective study in a consecutive cohort of 40 young patients (age <40 years) with a DVT and without a known cancer. All patients were diagnosed in our hospital during the period of 1988-1992. At the time of diagnosis, a routine examination to detect the presence of malignant disease was made. For the follow-up, all patients included in the study were asked to return to our unit and were interviewed for symptoms that could suggest a malignant disease. The mean follow-up was five years (from three to eight years). Twenty-four patients had DVT in the lower limbs and three in the upper extremities, nine had pulmonary embolism (six of them with DVT) and four had DVT in other sites. Sixteen patients (40%) had secondary DVT due to nonbiological causes, abnormalities in hemostasis were found in 14 patients (35%), and biological or environmental triggering factors were not identified in 10 patients (25%). Malignancies were not detected at diagnosis and in the follow-up. In our experience, venous-thrombotic patients under the age of 40 have a low incidence of subsequent cancer. Further studies should be performed to confirm this observation and to ascertain whether extensive screening for cancer is a cost-effective approach.

Chlorambucil-induced inappropriate antidiuresis in a man with chronic lymphocytic leukemia

The syndrome of inappropriate antidiuretic hormone (SIADH) has been described in patients suffering from leukemia or lymphoma involving the central nervous system. Several alkylating agents have also been associated with this syndrome. We describe a patient with chronic lymphocytic leukemia, without evidence of central nervous system involvement, who suffered from SIADH presumably caused by small doses of chlorambucil.

Bone marrow involvement in lymphoblastic lymphoma and small non-cleaved cell lymphoma: the role of trephine biopsy

Trephine biopsy (TB) combined with bone marrow aspiration (BMA) is the most common method for evaluating bone marrow (BM) involvement in non-Hodgkin's lymphomas. Nevertheless, the role of TB in high-grade lymphomas remains controversial. We reviewed the results of 42 consecutive BMAs and TBs performed simultaneously in 29 patients with lymphoblastic lymphoma (LL) and small, non-cleaved cell lymphoma (SNCL). In LL, 8M involvement was documented in 35.4% of the cases by BMA and 22.5% of the cases by TB. In SNCL it was documented in 45.4% of the cases by BMA and 36.3% by TB. There were no statistically significant differences (p > 0.05) in the rates of BM involvement found by TB or BMA in the two types of lymphoma, although BMA appeared to be more sensitive than TB. These observations suggest that routine TB may not be necessary in assessing BM involvement in patients with LL and SNCL.