Wnt signaling has recently been implicated in the pathogenesis of cancer. We studied the activity of Wnt signaling in peripheral blood CLL lymphocytes, and the methylation status of seven soluble Wnt antagonists including WIF1, DKK3, APC, SFRP1, SFRP2, SFRP4 and SFRP5 by methylation-specific PCR in the peripheral blood CLL lymphocytes and bone marrow samples of CLL patients at diagnosis. In the peripheral blood CLL lymphocytes, constitutive activation of Wnt signaling was detected, associated with hypermethylation of the soluble Wnt inhibitors. In the diagnostic CLL marrow samples, methylation of the seven genes was detected in up to 36.4%. Moreover, twenty-three (52.3%) patients had methylation of at least one of these 7 genes, of whom 14 (60.8%) had methylation of two or more Wnt inhibitors. Apart from an association of advanced age with DKK3 methylation, there was no association of gene hypermethylation with either clinical characteristics (including age, gender, lymphocyte count at diagnosis, Rai stage and poor-risk karyotype) or survival. In conclusion, Wnt signaling is constitutively activated in CLL B-lymphocytes in association with methylation of multiple soluble Wnt antagonists. Methylation of these soluble Wnt antagonists, occasionally multiple genes, in primary CLL marrow samples suggested an important role in CLL pathogenesis. Moreover, our study underscored the importance of studying methylation of a panel of but not individual genes regulating a cellular pathway.

Aims: To investigate the correlation of various diagnostic cytologic features demonstrated in SurePath liquid-based cell preparations with the infection of high-risk human papillomavirus (HPV).

Methods: A case-control study design. 510 cases of SurePath specimens that had been tested for HPV DNA by Hybrid Capture 2 assay were retrieved and re-examined for ten cytologic features. Distribution of these features in high- and low-risk HPV types was compared and risk statistics were estimated. Effects of cervicitis on the manifestation of HPV cytologic changes were adjusted by means of logistic regression.

Results: Cytologic features of nuclear hyperchromasia, multinucleation and atypical metaplastic cells were predominantly noted in high-risk HPV infection in the category of ASCUS/LSIL. The odds ratios of these three features were 6 to 12 times higher in high-risk than low-risk HPV infection.

Conclusions: Some diagnostic cytologic features can be used as markers in Pap smear screening for assessing the types of HPV infection.

Objectives: H. pylori infection is a major health problem world wide and effective eradication of the infection is mandatory. The efficacy of recommended eradication regimens is approximately 70%. In order to avoid treatment failure and the consequent development of secondary resistance(s) it is important to choose the most appropriate first line treatment regimen. This choice should also be made based on the knowledge of the antimicrobial resistance peculiar to a given geographical area. We evaluated the prevalence of antimicrobial resistant H. pylori strains isolated from naive patients and from patients with previous unsuccessful treatments.

Methods: We studied 109 H. pylori-infected subjects (Group 1) who had never received an eradication treatment and 104 H. pylori-infected subjects (Group 2) who had failed one or more eradication treatments. Resistance to amoxicillin (AMO) , tetracycline (TET) , clarithromycin (CLA), metronidazole (MET) and levofloxacin (LEV) was determined by epsilometer test. Significance of differences was evaluated by ² test.

Results: 1) The prevalence of antimicrobial resistance was 0% vs 3.1% to AMO, 0% vs 2% to TET, 27% vs 41.3% to MET (p<0.05), 18% vs 45.8% to CLA (p<0.05), 3% vs 14.6% to LEV (p<0.05) in Group 1 vs Group 2, respectively; 2) In Group 2 , there was an increased prevalence of H. pylori strains resistant to multiple antimicrobials.

Conclusions: This study confirms the high prevalence of H. pylori strains resistant to CLA and MET and indicates that unsuccessful treatments significantly increase resistance. Choosing eradication regimens other than standard triple therapy as first line therapy should be advisable in areas with high primary antimicrobial resistance prevalence.

Aims: The lymph node harvest from colorectal specimens is pivotal for colorectal cancer (CRC) patients, independent of N stage. This study was designed to determine whether the use of GEWF solution (glacial acetic acid, ethanol, destilled water, and formaldehyde) could improve the lymph node harvest in CRC specimens.

Methods: Consecutive fresh colonic (n=60) and rectal (n=60) specimens from patients with primary CRC resected at Aarhus University Hospital THG between March 2006 and July 2007 were randomized to either conventional preparation or GEWF preparation and examined in a standard manner.

Results: For colonic as well as rectal specimens, the GEWF solution increased the mean lymph node harvest from 9 and 10 to 16 and 17 lymph nodes per specimen compared to conventional prepared specimens, P<0.001. Using the recommended threshold of 12 lymph nodes to ensure adequacy of nodal harvest, the adequacy increased from less than half to almost three quarter independent of tumor origin, P<0.037. The proportion of node-negative specimens did not differ statistical significantly among the two preparation groups.

Conclusion: The use of GEWF solution may have diagnostic and therapeutic consequences for CRC patients, since the lymph node harvest of their resected specimens increased statistical significantly.

Chronic granulomatous disease (CGD) is characterized by granulomatous inflammation of multiple organ systems secondary to a defect in the ability to generate reactive oxidative species. The most common and severe form of CGD is an X-linked recessive disorder attributable to a defect in the gene encoding the gp91^phox subunit of NAPDH oxidase, which is involved in microbial killing. This defect predisposes individuals to severe and recurrent bacterial and fungal infections. Ocular manifestations include keratitis and chorioretinal lesions. The pathogenesis of the chorioretinal lesions is unknown. We describe the first case, in which Pseudomonas aeruginosa (P. aeruginosa) DNA is detected in the chorioretinal lesion of an 18-year old male with CGD who expired from multiple systemic infections including P. aeruginosa pneumonia following intensive immune suppression for inflammatory bowel disease. Our detection of P. aeruginosa molecular signature in the eye offers insights into the pathogenesis of ocular lesions seen in CGD.

Background: MicroRNAs have recently taken center stage as short noncoding RNAs that regulate mRNA expression.

Aim/Methods: To assess the feasibility of microRNA techniques in routinely processed tissues, we examined the accessibility of two representative microRNAs by real-time quantitative PCR in 86 human formalin-fixed paraffin-embedded (FFPE) samples from liver, breast, bone marrow, lymphatic tissues and colon. Murine liver was used to analyze the influence of fixation time and different fixatives.

Results: High quality microRNA was successfully extracted from routinely processed formalin-fixed tissues, resembling PCR amplification results from snap-frozen material analyzed in parallel. While fixation time does not affect microRNA accessibility, non-buffered formalin or fixative supplements like glutaraldehyde influence PCR results. Storage of human tissues for up to seven years did not deteriorate microRNA significantly. However, microRNA quality in human archival material following routine processing 10 to 20 years ago was decreased. Oxidation by ambient air during storage and fixation in unbuffered formalin are possible reasons for loss of microRNA quality.

Conclusion: The assessment of microRNAs in readily obtained FFPE samples is a highly promising tool in molecular pathology when similarly treated samples are analyzed. Therefore, microRNA analyses will gain wider acceptance as an adjunct to morphological tissue assessment in routine pathology and retrospective studies.

Aims: To determine what skills make a good consultant haematological microscopist; to explore how these skills develop during training and to determine whether these skills are maintained following training.

Methods: Twenty consultant haematologists underwent a semistructured interview to explore these issues. The interviews were transcribed and analysed for common themes using the N-vivo analytic package. This provides rich subjective qualitative data as opposed to hard objective quantitative data.

Results: Experience, methodicity and interest were the commonest skills mentioned. However, 25% of interviewees admitted they no longer followed a format when reporting. Interviewees agreed they had passed from a hypothetico-deductive to a scheme-inductive diagnostic reasoning model during acquisition of expertise. Only 20% had undertaken refresher training since becoming consultants, but the majority undertake some peer review of their work.

Conclusions: These skills could form the basis of vocational and revalidation assessments in the practice of haematological microscopy. The elucidation of such skill development can help refine standards and remedial training through the process of ‘deliberate practice’. Finally, the low uptake of refresher courses for established consultants needs serious consideration.

Peripheral T-cell lymphomas (PTCLs) account for about 12% of lymphoid tumours worldwide. Almost a half of them show such a morphologic and molecular variability as to hamper any further classification and to justify their inclusion in a waste-basket category termed "not otherwise specified (NOS)". The latter corresponds to neoplasms with aggressive presentation, poor response to therapy and dismal prognosis. Conversely to B-cell lymphomas, PTCLs have so far been the object of a limited number of studies aiming to elucidate their pathobiology and identify novel pharmacologic approaches. Herewith, the authors revise the most recent contributions on the subject, based on the experience they gained in the extensive application of micro-array technologies. PTCLs/NOS are characterised by erratic expression of T-cell associated antigens, including CD4 and CD52, recently proposed as targets for ad hoc immunotherapies. They also show variable Ki-67 marking, rates > 80% heralding a worse prognosis. Gene expression profiling (GEP) studies reveal that PTCLs/NOS derive from activated T-lymphocytes, more often of the CD4+ type, and bear a signature composed of 155 genes and related products that play a pivotal role for cell signalling transduction, proliferation, apoptosis and matrix remodelling. This observation seems to pave the way to the usage of innovative drugs, such as tyrosine kinase and histone deacetylase inhibitors whose efficacy has been proven in PTCL primary cell cultures. GEP does also allow better distinction of PTCL/NOS from angioimmunoblastic T-cell lymphoma, the latter being characterised by follicular T-helper lymphocyte derivation and CXCL13, PD1 and VEGF expression.

The placenta is the fetal organ providing the interchange between mother and fetus. This organ needs to provide its function such as transport and secretion even during its development and thus all developmental changes need to be in accordance with its function. Here the reader will find information on the development of the placenta during the first few weeks of pregnancy until the villous trees with their vasculature are established. Furthermore, there will be insights into the macroscopic anatomy of the delivered placenta as well as the microscopic anatomy and histology of this organ. This includes the different types of villi and the most important cellular components of the villi such as villous trophoblast, Hofbauer cells, mesenchymal cells and endothelium. Finally a short paragraph on fibrinoid and its localization is presented.

Rabies viral encephalitis, though one of the oldest recognized infectious disease remains an incurable, fatal encephalomyelitis despite significant advances in understanding of its pathobiology. Advances in science has led us to the trail of the virus in the host, but the sanctuaries in which the virus remains hidden or "latent" for its survival is unknown. Insights into host-pathogen interactions has facilitated evolving immunologic therapeutic strategies but we are far from finding a cure. To explain dichotomy in clinical presentation and uniform mortality in this viral encephalitis, various factors have been implicated that include both viral and host factors such as neuroanatomical distribution of viral antigen within brain, alteration in host immunity or viral strain in the former whereas apoptosis, neuronal dysfunction and neurotransmitter abnormalities in critical neuroanatomical areas are the popular explanations for the latter. Most of the present day knowledge has however evolved from invitro studies using fixed (attenuated) laboratory strains that may not be applicable in the clinical setting. Much has to be learnt about this elusive virus before effective therapeutic strategies can be evolved. This review attempts to address some of these questions that have remain unanswered in light of knowledge available from recent advances.

Aims: Although they are non specific, minimal intestinal lesions are at the end of the coeliac histological damage spectrum. To investigate whether minimal intestinal lesions in patients without endomysial antibodies are due to coeliac disease, we studied not only their prevalence and causes but also their risk of evolving into frank coeliac disease.

Methods: From Jan-2000 to Dec-2005, 645 duodenal biopsies were performed. In 209 patients, duodenal biopsies were performed independently of endomysial antibody results. Clinical data and HLA-typing of all the patients negative to endomysial antibodies but with minimal mucosal lesions were re-evaluated. Three years later, they were offered to be seen again and further investigations were proposed.

Results: 14 out of 209 patients had minimal mucosal lesions and negative endomysial antibodies. Two patients were lost to follow-up; in 7/12 patients, symptoms and histological lesions were due to a different condition, not related to coeliac disease. In 11/12 patients, HLA-typing made diagnosis of coeliac disease very unlikely. Only one patient was on a gluten-free diet because of gluten-sensitive symptoms and was DQ2+/DQ8+.

Conclusions: Minimal duodenal lesions in patients negative to endomysial antibodies are rare and are likely to be due to conditions unrelated to coeliac disease.

The gross examination is critical to making accurate diagnoses on placental specimens. An orderly evaluation of the cord, membranes and villous tissue allows maximal opportunity to recognize abnormalities. Many lesions have a pathognomonic gross appearance while other processes are best seen on histology. Quantitation of the volume of placental tissue involved in by an abnormal process is necessary to distinguish normal variation from significant pathology. Histologic sections must include cord, membranes and central villous tissue.

Solid pseudopapillary tumours (SPT) of the pancreas are uncommon, but with widespread and increased imaging several of these lesions are coming to light incidentally and are subject to needle biopsies. On limited material and especially the solid or clear cell variants of SPT can morphologically mimic most notably pancreatic neuroendocrine tumours and even metastatic renal cell carcinoma or melanoma. In this context, immunohistochemistry is important and useful in helping to reach the correct diagnosis.

Several antibodies have been used in the immunohistochemical evaluation of SPT. As with most tumours, no one marker is specific but rather a core panel is advocated. Recently, both β-catenin and E-cadherin have shown to be of value in SPT. Nuclear and cytoplasmic decoration of tumour cells by β-catenin is seen almost 100% of cases. This protein relocalization from the cell membrane is underscored by mutations of the β-catenin gene. Mutations of the E-cadherin gene are very uncommon in SPT but the immunohistochemically-detected changes to the protein are consistent and present in 100% of cases. Using an E-cadherin antibody to the extracellular domain of the molecule results in complete membrane loss, while the antibody directed to the cytoplasmic fragment produces distinct nuclear staining of the tumour cells. In addition, there is concordance of staining abnormalities between the two antibodies. When combined with CD10 and progesterone receptor positivity, a diagnosis of SPT can be rendered with confidence even in small biopsy samples.

Pancreatic intraductal papillary mucinous neoplasms (IPMNs) are mucin producing neoplasms with frequent papillary architecture that arise within the pancreatic ducts and are increasingly being recognized. Because they exhibit a spectrum of dysplasia ranging from low grade to high grade and may also have associated invasive carcinoma, and because they are clinically detectable, they are now intensively studied. There is marked overlap between IPMNs and pancreatic intraepithelial neoplasia (PanIN), such that the distinction between these two lesions is nearly impossible in certain cases. In addition, IPMNs sometimes can be confused with other primary cystic lesions of the pancreas. As a result, the correct diagnosis of IPMN can be challenging. This review addresses the clinical and pathological features of IPMNs, emphasizing their diagnostic criteria, differential diagnosis, and biologic behavior. Problematic issues in the pathologic evaluation of IPMNs are discussed.

Aims:Most staphylococci grown from blood cultures are contaminants. Since they are microscopically indistinguishable from non-contaminants, considerable time and resources may be spent following up all patients with positive blood cultures before the identification is made the following day. Since there is no formal guidance or standard available in this area, we surveyed practice in our region.

Methods: Telephonic interview using a standardized questionnaire. Results were analysed using descriptive techniques.

Results: The majority of microbiologists did not communicate all presumptive staphylococci but waited for identification in some cases.

Conclusion: There is a range of practice in our laboratories due to conflicting pressures: limited time, fear of criticism if results are not phoned, fear of causing confusion with provisional information, and lack of clarity concerning what is ‘good practice’. From this survey, we concluded that a decision not to telephone every presumptive staphylococcus in blood cultures on Day 1 is reasonable.

There have been recent major advances in obstetric ultrasound, both regarding technologies and expertise, such that high-resolution antenatal structural imaging, determination of maternal and fetal blood flow parameters and 3D and 4D ultrasound, are part of routine practice. This has resulted in changes in the way antenatal and obstetric care is now delivered. For example, antenatal and obstetric management of pregnancies complicated by intrauterine growth restriction (IUGR) and pre-eclamptic toxaemia (PET) is now dependent on several sonographic techniques including Doppler indices of the umbilical cord and maternal uterine arteries, hence ultrasound findings have become an increasingly common indication for placental pathological examination. The quality of specialist surgical pathology reports is related to pathologist expertise and, regarding the placenta, it has been reported that about 40% of placental diagnoses made by non-specialist pathologists were incorrect on specialist review, 90% being errors due to unrecognised lesions and 10% erroneous diagnoses,1 many of these differences possibly being related to pathologist unfamiliarity with current obstetric technologies. This review aims to provide an overview of relevant obstetric ultrasound techniques and their clinical relevance to the diagnostic pathologist, primarily focussing on conditions with specific placental implications. There are several detailed texts regarding histological findings and their implications of placental pathological lesions,2-4 and therefore this review will specifically discuss the pathological correlates of sonographic findings, with details of the specific histological entities being found elsewhere. The aim of pathological examination of the placenta is to determine the pathological basis for the clinical findings and advance understanding of the pathophysiology of pregnancy complications.

Microsatellite analysis is an important tool in clinical research and molecular diagnostics, because microsatellite instability (MSI) occurs frequently in various types of cancer. Approximately 10-15% of colorectal, gastric or endometrial carcinomas are associated with MSI, which has an impact on clinical prognosis.

The microsatellite loci Bat25, Bat26, D2S123, D5S346, and D17S250, recommended by the Bethesda guidelines, were analysed by microfluidic-based on-chip electrophoresis in 40 cases of colon carcinoma with known MSI status. In all cases, microfluidic separation of the PCR amplicons resulted in highly resolved, distinct patterns of each of the five microsatellite loci. Detection of MSI could be demonstrated by microsatellite loci-associated, well-defined deviations in the electropherogram profiles of tumour and non-tumour material and confirmed the classification of MSI cases performed by conventional technology.

In conclusion, microfluidic chip technology is a simple and reliable approach for MSI detection, which allows label-free and very fast analysis of microsatellite amplicons.

Background: The relationship between tumefactive lesions classified as sclerosing mesenteritis and IgG4-related sclerosing disorders (e.g. lymphoplasmacytic sclerosing pancreatitis/autoimmune pancreatitis) remains uncertain.

Aims: In this study, lesions coded as "sclerosing mesenteritis" were reviewed for findings in keeping with IgG4-related sclerosing disorders.

Methods: Inclusion in the study required available paraffin blocks for IgG4 staining and documentation of a mass lesion.

Results: A total of nine mesenteric lesions ranging from 3-14 cm were identified in 6 male and 3 female patients. On hematoxylin and eosin-stained sections, all were characterized as loosely marginated fibroinflammatory processes with variable amounts of fat necrosis. Lymphocytic venulitis/phlebitis was identified in 8 of 9 cases. IgG and IgG4 expression in lesional plasma cells was assessed by immunohistochemistry (IHC). IgG4-positive plasma cells were counted in the areas of greatest density in ³ 3 high power fields (HPFs). The highest number per HPF was recorded and a score assigned based on the following scale: <5/HPF- none/minimal; 5-10/HPF-mild; 11-30/HPF- moderate; >30/HPF- marked. The relative proportion of IgG4-reactive plasma cells to total IgG-positive plasma cells was assessed. IgG4-reactive plasma cells ranged from 0 to >100 in the most dense zones (3 cases- none/minimal, 4 cases- moderate, 2 cases- marked).

Conclusions: Although this study is limited by small numbers, our findings suggest that some tumefactive lesions regarded as sclerosing mesenteritis may be a subset of IgG4-related sclerosing disorders.

Hereditary breast cancer accounts for up to 5-10% of all breast carcinomas. Recent studies have demonstrated that mutations in two high penetrance genes, namely BRCA1 and BRCA2, are responsible for about 16% of the familial risk of breast cancer. Even though subsequent studies have failed to find another high-penetrance breast cancer susceptibility gene, several genes that confer moderate to low risk of breast cancer development have been identified; moreover, hereditary breast cancer can be part of multiple cancer syndromes. In this review we will focus on the hereditary breast carcinomas caused by mutations in BRCA1, BRCA2, Fanconi Anaemia (FANC) genes, CHK2 and ATM tumour suppressor genes. We describe the hallmark histological features of these carcinomas compared with non-hereditary breast cancers and show how an accurate histopathological diagnosis may help improve the identification of patients to be screened for mutations. Finally, novel therapeutic approaches to treat patients with BRCA1 and BRCA2 germline mutations, including cross-linking agents and PARP inhibitors, are discussed.

Aims: BRCA1-related breast cancer is associated with a basal-like phenotype, and is frequently estrogen receptor and HER2-negative. The expression of EGFR has been considered to be one component of the basal-like phenotype, but no standard criteria exist. We have studied the relationship between EGFR expression, BRCA1 status and basal markers with respect to clinico-pathological associations and prognosis, in addition to an evaluation of different criteria for EGFR assessment by immunohistochemistry.

Methods: A tissue microarray comprising 230 available cases from our series of primary invasive breast cancer diagnosed in Ashkenazi Jewish women during 1980-1995, was stained for EGFR using the Dako PharmDX kit, and evaluated by Webslide virtual microscopy.

Results: EGFR was positive in 9-19% according to different criteria. Expression was associated with BRCA1 carrier status and basal-like markers as negative ER, positive CK 5/6 and positive P-cadherin staining. EGFR was prognostically significant by univariate and multivariate analysis within the group carrying germ-line BRCA1 mutations. Histological grade, axillary lymph node status and P-cadherin status had significant independent value in the final multivariate model including all cases, whereas EGFR was not significant in this model. All five scoring systems gave comparable results concerning clinico-pathological associations and patient outcome, although the most restrictive criteria (EGFR-HI) tended to be most sensitive in predicting BRCA1-status, a basal phenotype, and patient prognosis.

Conclusions: EGFR expression, being present in 9-19% of the cases, was prognostically significant among BRCA1 mutated cases only. In multivariate survival analysis of all cases, no independent effect was seen. Still, EGFR immunostaining might be relevant to predict the response to targeted therapy, and this should be studied further.

MYCN is the most commonly amplified gene in human neuroblastomas. This proto-oncogene has been overexpressed in a mouse model of the disease in order to explore the role of MYCN in this tumour.

Aims: To report the histopathological features of neuroblastomas from MYCN transgenic mice.

Methods: 27 neuroblastomas from hemizygous transgenic mice and 4 tumours from homozygous mice were examined histologically, and Ki67 and MYCN immunocytochemistry performed in 24 tumours.

Results: Tumours obtained from MYCN transgenic mice resembled human neuroblastomas, displaying many of the features associated with stroma-poor neuroblastoma including heterogeneity of differentiation (but no overt ganglionic differentiation was seen), low levels of Schwannian stroma and a high mitosis karyorrhexis index. The tumours had a median Ki67 labelling index of 70% and all tumours expressed MYCN with a median labelling index of 68%. The most striking difference between the murine and human neuroblastomas was the presence of tingible body macrophages in the transgenic mouse tumours reflecting high levels of apoptosis. To our knowledge this has not previously been described in human or other murine neuroblastoma models.

Conclusions: These studies highlight the histological similarities between tumours from MYCN transgenic mice and human neuroblastomas, and reaffirm their role as a valuable model to study the biology of aggressive human neuroblastoma.

Disseminated Cryptococcosis is an uncommon occurrence in immunocompetent populations and occurs mainly in immunocompromised patients. We describe the first reported case of Cryptococcus meningitis and skin lesions in a 4 year old confirmed HIV negative boy who presented with fever, meningism and skin lesions. On examination he was confused, uncooperative, had neck stiffness and raised skin lesions. A septic screen, including skin scraping, was performed and he was on an empiric stat dose of Penicillin and Ceftriaxone for suspected meningococcal meningitis. The cerebrospinal fluid revealed normal protein, glucose and chloride levels; yeasts were observed on Gram stain from the CSF and skin scraping. The India ink stain and Cryptococcus neoformans latex agglutination test on the CSF were both positive. Bacterial culture of the skin biopsy, CSF and blood culture specimens was negative. He was treated with Amphotericin B based on preliminary results and had a gradual, recovery with no neurological sequelae. He continued oral Fluconazole.

Background: Endoscopy and biopsy are used to diagnose celiac disease. There are however, observer dependent interpretations of the degree of villous atrophy in biopsies. We performed a pilot study using quantitative image processing procedures to quantify the degree of villous atrophy in patients with celiac disease.

Method: The degree of villous atrophy in duodenal biopsy images was quantified by calculating the ratio of villous edge to piecewise arc length (E/P ratio) and this value was compared to the blinded assessment of Marsh score for degree of villous atrophy.

Results: Mean E/P ratios for N=32 biopsy images: 2.76±0.44 (Marsh IIIa), 1.91±0.50 (Marsh IIIb) and 1.18±0.22 (Marsh IIIc) were significantly different (p=0.006). Based on nonparametric tests, E/P ratios were inversely correlated with the Marsh scores (Spearman’s coefficient = ­0.798, Kendall’s = -0.681; p<0.0001).

Conclusions: Biopsy images quantified by image analysis correlated exceedingly well with the histopathologic grade of villous atrophy. Since quantified measurements are real-numbered values and lack observer bias, measurement of villous atrophy based on image analysis lends itself to standardization of histologic grading.

The incidence of placenta accreta, defined as the abnormal adherence of the placenta to the uterine wall, has been increasing alarmingly in the developed as well as the developing world. There is considerable maternal morbidity and mortality related to the condition. The pathophysiology focusses on the balance between decidualisation on the one hand and trophoblast invasion on the other. Pathological diagnosis relies on the finding of placental villi in direct apposition to myometrium, either in hysterectomy specimens or in placental basal plates.

Placental examination in obstetric cases complicated by maternal or fetal disorders can provide insight into chronicity and etiology. This review considers two common complications of pregnancy, pre-eclampsia toxemia and intrauterine growth restriction and describes the placental pathologic features often present.

We report a case where displaced non-neoplastic ovarian granulosa cells within the fallopian tube mimicked a small cell carcinoma. This peculiar phenomenon of displaced granulosa cells has been described previously in the ovary as a rare diagnostic pitfall which may be misinterpreted as metastatic carcinoma. To the best of our knowledge, this is the first documentation of its occurrence in the fallopian tube. Awareness of this rare phenomenon and immunostaining for markers of sex cord differentiation assist in diagnosis and in preventing a false positive diagnosis of malignancy.

NUT midline carcinoma (NMC) is a rare, highly lethal cancer that occurs in children and adults of all ages. NMCs uniformly present in the midline, most commonly in the head, neck, or mediastinum, as poorly differentiated carcinomas with variable degrees of squamous differentiation. This tumor is defined by rearrangement of the Nuclear protein in testis (NUT) gene on chromosome 15q14. In most cases, NUT is involved in a balanced translocation with the BRD4 gene on chromosome 19p13.1, an event that creates a BRD4-NUT fusion gene. Variant rearrangements, some involving the BRD3 gene, occur in the remaining cases. NMC is diagnosed by detection of NUT rearrangement by fluorescence in situ hybridization or RT-PCR. Due its rarity and lack of characteristic histologic features, most cases of NMC currently go unrecognized.

Brucella spp. is an uncommon class 3 pathogen isolated in laboratories serving nonendemic areas. We report four recent cases of brucellosis diagnosed at five different London laboratories which highlights the need to maintain a high index of suspicion for brucellosis in patients with a history of travel to and/or consumption of unpasteurised foods from endemic areas. We propose a protocol for risk categorisation, and describe the strategy adopted for serological follow-up of exposed staff and use of postexposure prophylaxis.

Background: Loss of control of mucosal crypt cell proliferation resulting in a hyperproliferative field change occurs early in the adenoma-carcinoma sequence. Ki-67, the current gold-standard marker of cellular proliferation, is a cell cycle protein that may lack sensitivity in demonstrating altered mucosal crypt cell dynamics. Minichromosome maintenance protein 2 (MCM2) has a specific role in DNA replication and has been proposed as a new marker for screening for colorectal cancer. Aim: To compare the expression of Ki-67 with MCM2 in colorectal mucosa associated with colorectal cancer. Methods: Ki-67 and MCM2 immunostaining was performed on serial sections taken from formalin-fixed, paraffin-embedded specimens. Labelling indices (LI’s) were calculated by counting the proportion of positively stained nuclei in representative areas of adenocarcinoma, and in equivalent superficial, middle, and basal crypt compartments of mucosa sampled 1cm from the tumour (Ca1) and 10cm from the tumour (Ca10). Results: Specimens were obtained from 43 patients. Most nuclei in specimens of adenocarcinoma stained positively for MCM2 and Ki-67. In Ca1 and Ca10 samples significantly greater staining was seen in all crypt compartments with MCM2 compared with Ki-67. Receiver operator characteristic curve analysis suggested that proliferation changes (assessed either by MCM2 or by Ki-67) in Ca10 but not Ca1 mucosa significantly predicted for origin from a carcinoma-associated colon. Conclusions: MCM2 was more sensitive than Ki-67 in identifying colorectal mucosal proliferation. Increased proliferation (assessed either by MCM2 or Ki-67) in mucosa at 10 cm but not at 1 cm from the carcinoma, significantly predicted for origin from a carcinoma-associated colon.

A previously healthy male with subacute onset right leg weakness is suspected to have an astrocytoma after a lesion is demonstrated via imaging. However a subsequent biopsy demonstrated the presence of foamy macrophages containing periodic acid-Schiff staining granules, suggesting Whipple’s disease as a possible diagnosis. We here present the case and the report on the patient’s current clinical status.

Result of the immunohistochemical reactions routinely used in diagnostic surgical pathology should be properly interpreted, since false results, related to technical and interpretative pitfalls may lead to incorrect diagnosis. We review of the main sources of such pitfalls, analytically described and related to different steps (fixation, tissue processing and embedding, decalcification, antigen retrieval) which may affect the accuracy of immunohistochemistry. In addition, presence of endogenous enzyme activity, improper binding of avidin to endogenous biotin, incorrect use of antibodies, chromogen and detection system, as well as incorrect interpretation may produce unreliable data. The high frequency and extension of such pitfalls make mandatory the use of internal and external controls and adoption of cross-validation programs. The present study, supported by an extensive review of the related literature is intended as a guideline leading to proper interpretation of immunohistochemical data, an essential component of the diagnostic process. Our experience on the antigen retrieval procedures for different antigens is also presented.

We present a broad overview, with examples, of the potential pitfalls encountered in the clinical immunology laboratory. Illustrative examples and cases are provided from autoimmunity, immunochemistry and cellular immunology, looking both at technical and interpretative pitfalls.

Background: In the United States, the lack of processes standardization in histopathology laboratories leads to less than optimal quality, errors, inefficiency, and increased costs. The effectiveness of large scale quality improvement initiatives rarely has been evaluated.

Aim: To measure the effect of implementation of a Lean quality improvement process on the efficiency and quality of a histopathology laboratory section.

Methods: We performed a non-concurrent interventional cohort study from January 1, 2003 to December 31, 2006 and implemented the Lean process on January 1, 2004. We also compared the productivity of the Lean histopathology section to a sister histopathology section that did not implement Lean processes. We measured pre- and post-Lean specimen turn-around time and productivity ratios (work units/full time equivalents). For 200 Lean interventions, we used a 5-part Likert scale to assess the impact on error, success, and complexity.

Results: In the Lean laboratory, the mean monthly productivity ratio increased from 3,439 and 4,074 work units/full time equivalents (P < 0.001) as the mean daily histopathology section specimen turn-around time decreased from 9.7 to 9.0 hours (P = 0.01). The Lean histopathology section had a higher productivity ratio compared to a sister histopathology section (1,598 work units/full time equivalents, P < 0.001) that did not implement Lean processes. The mean impact, success, and complexity of interventions were 2.4, 2.7, and 2.5, respectively. The mean number of specific error causes affected by individual interventions was 2.6.

Conclusion: We conclude that Lean process implementation improved histopathology section efficiency and quality.

This third best practice review examines four series of common primary care questions in laboratory medicine: (i) 'minor' blood platelet count and haemoglobin abnormalities, (ii) diagnosis and monitoring of iron deficiency anaemia , (iii) secondary hyperlipidaemia and hypertriglyceridaemia and (iv) HbA1c and microalbumin use in diabetes. The review is presented in question-answer format, referenced for each question series. The recommendations represent a précis of guidance found using a standardised literature search of national and international guidance notes, consensus statements, health policy documents and evidence-based medicine reviews, supplemented by MEDLINE EMBASE searches to identify relevant primary research documents. They are not standards but form a guide to be set in the clinical context. Most are consensus rather than evidence-based. They will be updated periodically to take account of new information.