Piergiovanni Grigolato

Severe hepatotoxicity during combination antiretroviral treatment: Incidence, liver histology, and outcome

Objectives: To assess incidence, risk factors, histology, and outcome of severe hepatotoxicity (SH) during antiretroviral treatment (ART). Methods: Seven hundred fifty‐five HIV‐seropositive patients consecutively prescribed new ART were selected. Liver function tests were assessed at baseline, after 1 month, and every 4 months thereafter. Liver biopsy was recommended in case of SH (i.e., increase in liver enzymes ≥10 times the upper limit of normal or 5 times baseline if markedly abnormal). Results: Twenty‐six cases of SH were observed with an incidence of 4.2% personyears. Liver failure (LF) was rarely seen (1.1 per 100 person‐years). Liver damage was invariably observed in patients with chronic viral hepatitis. Liver histology showed exacerbation of viral hepatitis in all 16 patients for whom a liver biopsy was available at the time of SH. A direct correlation was found between alanine aminotransferase increase and increase in CD4+ T‐cell count in patients with SH (r = 0.53, p < .001). Death occurred during follow‐up in 7 of 26 (27%) patients, all of whom showed LF and baseline CD4+ count less than 200 cells/mm3 (7/7 patients = 100% vs. 8/19 patients without LF; p < .01). Relapse of SH was observed after ART was recommenced in 7 of 17 (41%) patients. Five of these 7 patients did not show further SH relapse after treatment with interferon. Conclusions: This study provides estimates of SH and LF in a large populationbased setting where hepatitis C virus coinfection is highly prevalent and provides indications that liver damage may be caused by immune reconstitution and related exacerbation of viral hepatitis. A strict follow‐up for hepatotoxicity is mandatory when ART is initiated in patients with <200 CD4+ T cells/mm3. Antihepatitis pre‐ or comedication could be an effective preventive or curative measure.

Dilated Intercellular Spaces as Markers of Reflux Disease: Histology, Semiquantitative Score and Morphometry upon Light Microscopy

Background and Aims: A recent electron microscopy study suggested that dilated intercellular spaces (DIS) are specific for acid reflux-damaged esophageal epithelium. Electron microscopy is, however, expensive and difficult to apply to routine biopsies. The aims of this study are to establish a method for assessing DIS on light microscopy of esophageal biopsies and to estimate its association with current clinicopathological parameters of esophagitis. Materials and Methods: 21 patients with reflux symptoms were investigated. Light microscopy biopsies were assessed for DIS size by a semiquantitative method and computer-assisted, static morphometry. A DIS score accounting for DIS size and distribution was assigned to each patient and its association with 30 clinicopathological variables investigated by univariate and multivariate logistic regression. Results: Both the semiquantitative method and static morphometry identified 4 different classes of DIS size. The DIS score was significantly and independently associated with the esophageal symptoms score, the histological score of esophagitis and the relevant morphometry data. Conclusions: DIS may be efficiently assessed during light microscopy of routine esophageal biopsies. Since correlation with both the histology and the symptoms of esophagitis, the DIS score may be considered a novel parameter of esophagitis and is suggested for the routine evaluation of esophageal biopsies in patients with reflux disease.

Dilated intercellular spaces : A major morphological feature of esophagitis

Objectives: Dilated intercellular spaces (DIS) in the esophageal epithelium have been identified by electron microscopy as marker of acid reflux damage in experimental animals and adults with gastroesophageal reflux disease (GERD). We aimed to identify and quantify DIS by light microscopy in pediatric GERD and esophagitis. Methods: We prospectively took esophageal biopsies in 70 consecutive pediatric patients, 48 of whom had GERD symptoms. On hematoxylin and eosin-stained sections esophagitis was scored histologically, and DIS were graded as 0 (absent), + (small and focal), ++ (moderate) or +++ (large and diffuse). A computerized image analysis identified total, cellular and nuclear areas and DIS were quantified as percentage of total minus cellular area. Results: Forty of 48 GERD patients had histological esophagitis (33 G1, 4 G2, 3 G3, 1 of which with Barrett esophagus), and all 40 had DIS (33 +, 4 ++, 3 +++) with 100% interobserver agreement; 15 of 29 (55%) had abnormal pH study (reflux index, 5.7%-36%). In 30 patients the esophagus was histologically normal. DIS values were 2.21% ± 2.60% (range, 0.11%-12%) in patients with esophagitis and 0.44% ± 0.13% (0.2%-0.7%) in patients with normal histology (P < 0.00001), with 0.71% bearing 70% sensitivity and 100% specificity for GERD versus controls. Five other children with esophagitis unrelated to GERD (eosinophilic, Candida, food allergy) also had DIS + to +++, and median DIS area was 5% (1.3%-12%). Conclusions: DIS can be detected and evaluated by light microscopy, and the image analysis used provides an objective quantification of DIS and supports the light microscopy evaluation. DIS are a morphological feature of GERD and esophagitis in infancy and childhood.

Nodal and extranodal tumor-forming accumulation of plasmacytoid monocytes/interferon-producing cells associated with myeloid disorders

Nodal tumor-forming accumulations of plasmacytoid monocytes/interferon-producing cells (PMs/IPCs) have been described in patients with myeloproliferative disorders. Here we report a series of 9 additional cases of such association. The patients were predominantly adult (median, 62 years), males (male/female ratio, 7:2), who presented with chronic myelomonocytic leukemia (4 cases), acute myeloid leukemia (1), acute monocytic leukemia (2), unclassifiable chronic myeloproliferative (1), or myeloproliferative/myelodysplastic disease (1). The prognosis was poor (median survival, 24 months) and related to progression of the underlying myeloid neoplasm. We found that in addition to lymph nodes, PMs/IPCs accumulated to bone marrow (8 cases) and skin (4 cases). Immunohistochemical markers typically expressed by PMs/IPCs (CD68, CLA/HECA452, CD123) were found in all cases and shown useful to identify cells with variations from classic morphology. In addition, PMs/IPCs expressed the interferon-α (IFN-α) inducible protein MxA, the B-cell oncogene TCL1, and granzyme B. The biologic and clinical significance of the association between PMs/IPCs and myeloid disorders remains not clarified. Using fluorescence in situ hybridization analysis in a case known to harbor monosomy 7 in the myeloid leukemia, we demonstrated that PMs/IPCs share the same chromosomal abnormality, thus indicating that they are clonal, neoplastic in nature, and closely related to the associated myeloid tumor. Recently, a novel CD56+ hematologic neoplasm has been reported and retained to stem from PMs/IPCs. The majority of PMs/IPCs in the present series failed to express CD56, thus indicating that variants of PMs/IPCs neoplasms exist, which might represent parts of a spectrum.

The spleen in the Wiskott-Aldrich syndrome : Histopathologic abnormalities of the white pulp correlate with the clinical phenotype of the disease

The Wiskott-Aldrich syndrome (WAS) is a X-linked hematologic disorder characterized by thrombocytopenia, eczema, and immunodeficiency of variable severity. Reported here are the results of a morphologic, morphometric, and immunophenotypic analysis of splenic lymphoid tissue in 12 WAS patients with documented molecular defect and with different disease severity. Spleens from 29 age-matched patients with different diseases were used as controls. Paraffin-embedded tissue (from all cases) and fresh-frozen samples (from 5 WAS patients and 4 control subjects) were used to study the different white pulp compartments by classic morphologic, immunophenotyping, and image analysis techniques. Data were statistically analyzed by both parametric and nonparametric tests. Spleens from WAS patients showed a significant depletion of the total white pulp (p = 0.0008), T cell (p < 0.05), and B cell (p = 0.0002) areas and marginal zone (MZ) thickness (p < 0.0001). Among WAS patients, a negative correlation was found between the score of severity of the disease and all variables considered (Spearmans rank correlation coefficient, r = -0.79, r = -0.73, r = -0.68, and r = -0.56, respectively). In conclusion, this study shows that in WAS a general depletion of the splenic white pulp occurs, supporting the evidence that WAS is characterized by a combined immune defect. The significant reduction of the MZ may explain the inability of WAS patients to mount a response to T-independent antigens.

Malignancy-associated allelic losses on the X-chromosome in foregut but not in midgut endocrine tumours

Information on genetic changes involved in the progression of gastroenteropancreatic (GEP) endocrine tumours is scanty. On the other hand, the identification of molecular markers of malignancy could be crucial for the prognostic evaluation of these neoplasms, which is hardly predictable on the basis of conventional histological criteria. An association of X‐chromosome deletions with malignancy has already been found in gastric endocrine tumours. To investigate this further, a comparative loss of heterozygosity (LOH) analysis was performed on 17 pancreatic endocrine tumours (PETs) and 17 intestinal (ten ileal, six appendiceal, and one rectal) carcinoids from female patients. The relationship of X‐chromosome LOH with the ploidy status of the neoplasms was also investigated. LOH was found in six of eight malignant PETs (60% of the informative markers), but was infrequent in the nine benign ones (4.5%). In contrast, although retention of heterozygosity was consistently observed in benign midgut tumours, LOH was infrequent in malignant carcinoids (15%). No correlation was found between LOH and the ploidy status. These results indicate an association between X‐chromosome LOH and malignancy in foregut endocrine tumours. The lack of such an association in midgut carcinoids suggests that different molecular mechanisms are involved in the progression of these two categories of endocrine neoplasms, which are otherwise considered to be closely related. These findings emphasize the need for further molecular studies on GEP endocrine tumours, carefully subdivided according to their anatomical site of origin. Copyright

p53 is dispensable for apoptosis but controls neurogenesis of mouse dentate gyrus cells following γ-irradiation

Mammalian cells respond to DNA insults by activating cell-cycle checkpoints. This may result in a temporary cell growth arrest which allows DNA repair before proliferation or induces apoptosis. p53 is one of the main contributors in regulating these activities. To get a better insight on the molecular mechanism underlying these activities we studied the role of p53 in apoptosis and neurogenesis of brain cells from adult p53(+/+) or p53(-/-) mice exposed to gamma-irradiation. Apoptosis and neurogenesis were assessed up to 14 days following the injury. Five-ten hours following gamma-irradiation, cells with TUNEL positive nuclei were identified within the subgranular zone of dentate gyrus (DG) of both p53(+/+) and p53(-/-) mice. At the same time-points, pyknotic and shrinking nuclei were visualized by Hoechst 33258 staining. Furthermore, gamma-irradiation increased the number of proliferating cell nuclear antigen (PCNA) positive cells with a peak at 5-10 h in both animal groups. PCNA immunoreactivity was detected in cells exhibiting condensed nuclei as visualized by Hoechst 33258 staining. Neurogenesis, assessed by mitotic marker p34(cdc2) immunoreactivity, showed a biphasic response to gamma-irradiation both in p53(+/+) and p53(-/-) mice which was characterized by an early inhibition and a delayed stimulation. In p53(-/-) mice, the time required by DG granule cells to recover from the lesion and to stimulate proliferation was significantly shortened in comparison with wild-type mice thus resulting in an accelerated neurogenesis. Our data indicate that following gamma-radiation p53 plays a role in regulating cell-cycle progression rate but it is dispensable for promoting apoptosis of DG granule cells.

Application of alternative fixatives to formalin in diagnostic pathology.

Fixation is a critical step in the preparation of tissues for histopathology. The objective of this study was to investigate the effects of different fixatives vs formalin on proteins and DNA, and to evaluate alternative fixation for morphological diagnosis and nucleic acid preservation for molecular methods. Forty tissues were fixed for 24 h with six different fixatives: the gold standard fixative formalin, the historical fixatives Bouin and Hollande, and the alternative fixatives Greenfix, UPM and CyMol. Tissues were stained (Haematoxylin-Eosin, Periodic Acid Schiff, Trichromic, Alcian-blue, High Iron Diamine), and their antigenicity was determined by immunohistochemistry (performed with PAN-CK, CD31, Ki-67, S100, CD68, AML antibodies). DNA extraction, KRAS sequencing, FISH for CEP-17, and flow cytometry analysis of nuclear DNA content were applied. For cell morphology the alternative fixatives (Greenfix, UPM, CyMol) were equivalent to formalin. As expected, Hollande proved the best fixative for morphology. The morphology obtained with Bouin was comparable to that with formalin. Hollande was the best fixative for histochemistry. Bouin proved equivalent to formalin. The alternative fixatives were equivalent to formalin, although with greater variability in haematoxylin-eosin staining. It proved possible to obtain immunohistochemical staining largely equivalent to that following formalin-fixation with the following fixatives: Greenfix, Hollande, UPM and CyMol. The tissues fixed in Bouin did not provide results comparable to those obtained with formalin. The DNA extracted from samples fixed with alternative fixatives was found to be suitable for molecular analysis.

Rectal localization of metastatic lobular breast cancer

The incidence of extrahepatic gastrointestinal metastases from breast cancer is reported in the literature only as necroscopy studies (6–18 percent); they usually originate from lobular or a mixed ductal-lobular subtype. Nonspecific presenting symptoms, death of the patients caused by other more frequent metastases, and variable radiographic features mimicking primary neoplasms cause a clinical underestimation of this pathology. We report here a case of rectal metastasis from a lobular carcinoma eight years after mastectomy.

Defective migration of monocyte-derived dendritic cells in LAD-1 immunodeficiency

β2 Integrins (CD18) are required for leukocyte migration. In fact, the absence of CD18 results in type‐1 leukocyte adhesion deficiency (LAD‐1). We analyzed the distribution phenotype and function of dendritic cells (DCs) in three LAD‐1 patients with homozygous mutations of CD18. Two of them did not express CD18 (Patients A and C), and the other subject (Patient B) displayed reduced expression of β2 integrins because of a missense mutation. Analysis of DCs derived from Patients A and B showed an abnormal morphology and a severe impairment in transendothelial migration and chemotactic response to CCL19/macrophage inflammatory protein‐3β, suggesting that CD18 is required for migration of monocyte‐derived DCs. Nevertheless, DCs displayed normal macropinocytosis and underwent normal maturation after addition of tumor necrosis factor α. Finally, immunohistochemical analysis of lymph nodes from subjects B and C revealed a significant reduction in the number of factor‐XIIIa+ interstitial DCs in the interfollicular area in both patients, suggesting that CD18 plays a role in the migration of these cells in vivo.