Showing papers in "Journal of Clinical Pathology in 1989"

New method for detecting slime production by coagulase negative staphylococci.

Abstract: An alternative method for detecting the production of slime by coagulase negative staphylococci was compared with the routinely used Christensen method on 124 isolates of coagulase negative staphylococci from carriage sites, blood cultures, and infected peritoneal dialysis fluids. The alternative method requires the use of a specially prepared solid medium--brain heart infusion broth, supplemented with 5% sucrose, and Congo red stain. Of the 124 tests, there was complete agreement between methods in 107 and only one strain was clearly negative by Christensen's method while positive on Congo red agar. The Congo red method is rapid, sensitive, and reproducible and has the advantage that colonies remain viable on the medium. It is also not subject ot interbatch variation of media which sometimes affects the reproducibility of the Christensen method.

Proposals for the classification of chronic (mature) B and T lymphoid leukaemias. French-American-British (FAB) Cooperative Group.

Abstract: Peripheral blood, bone marrow films, and bone marrow biopsy specimens from 110 patients, well characterised by clinical and laboratory studies, including electron microscopy, were reviewed, to determine proposals for the classification of chronic (mature) B and T cell leukaemias. On the basis of cytology and membrane phenotype the following disorders were defined: (i) B cell type: chronic lymphocytic leukaemia (CLL); CLL of mixed cell type, which includes cases with more than 10% and less than 55% prolymphocytes (CLL/PL), and a less well defined form with pleomorphic lymphocytes but less than 10% prolymphocytes; prolymphocytic leukaemia (PLL); hairy cell leukaemia (HCL); HCL variant; splenic lymphoma with circulating villous lymphocytes; leukaemic phase of non-Hodgkin's lymphoma (follicular lymphoma, intermediate, or mantle zone lymphoma and others); lymphoplasmacytic lymphoma with peripheral blood disease (mostly Waldenstrom's macroglobulinaemia); and plasma cell leukaemia. (ii) T cell type: T/CLL, which was differentiated from reactive T/lymphocytosis; T/PLL; adult T cell leukaemia/lymphoma; and Sezary's syndrome. The recognition of distinct entities within the B and T cell leukaemias seems to have clinical and epidemiological connotations. It is hoped that these proposals may serve as the basis for further work, discussion, and improved management of patients.

KP1: a new monoclonal antibody that detects a monocyte/macrophage associated antigen in routinely processed tissue sections.

Abstract: A new monoclonal antibody, KP1, raised against a lysosomal fraction of human lung macrophages, recognises a fixation-resistant epitope in a wide variety of tissue macrophages (such as Kupffer cells germinal centre, splenic, and lamina propria macrophages), and in granulocyte precursors. Its broad reactivity with cells of the mononuclear phagocytic lineage was established by testing on routinely processed samples of normal and reactive lymphoid tissues. Interdigitating reticulum cells were unstained or showed limited cytoplasmic staining while Langerhans' cells and follicular dendritic reticulum cells were unreactive. KP1 recognises a molecule of about 110 kilodaltons in macrophage-rich human tissue when tested by either immunoprecipitation or Western blotting (although the latter procedure also shows two additional components with molecular weights of 70 and 40 kilodaltons). KP1 should be of considerable value for studying disorders of the monocyte/macrophage system, including both reactive and neoplastic states (such as true histiocytic proliferations).

Practical Medical Microbiology

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Observer variability in histopathological reporting of cervical biopsy specimens.

Abstract: Sections from 100 cervical biopsy specimens were studied by 12 consultant histopathologists to determine the robustness of the existing pathology terminology and classification. Analysis by kappa statistics showed good agreement in the diagnosis of CIN 3 and squamous carcinoma but an inability to distinguish accurately between the lesser grades of CIN. It is recommended that the classification be changed to low grade (present CIN 1 and 2) and high grade (present CIN 3) categories alone. There was very poor agreement in the identification of cellular changes associated with human papilloma virus (HPV) infection.

Lymphoid follicles in antral mucosa: immune response to Campylobacter pylori?

Abstract: The prevalence of lymphoid follicles in endoscopic biopsy specimens from normal antral mucosa (n = 220), mucosa with reflux gastritis (n = 104), and in cases with Campylobacter pylori-associated gastritis (n = 2544) was studied. In the latter group whether there were associations between degree and activity of gastritis and the prevalence of lymphoid follicles and between the occurrence of lymphoid follicles and the presence of intestinal metaplasia in the antrum were investigated. In cases with normal mucosa and in those with reflux gastritis lymphoid follicles were not detected, but mucosal lymphoid follicles were found in 1297 (54%) of the cases with C pylori-associated gastritis. The prevalence of lymphoid follicles in the antral mucosa depended on the degree and activity of the gastritis and also correlated with the presence of intestinal metaplasia. The development of lymphoid follicles in the mucosa of the antrum probably represents, primarily, an immune response to the colonisation of the mucosa by C pylori.

New spiral bacterium in gastric mucosa.

Abstract: A new spiral bacterium, distinct from Campylobacter pylori, was found in the gastric mucosa of six patients with gastrointestinal symptoms. All patients had chronic active type B gastritis and four had oesophagitis. Culture and microscopy for C pylori infection was negative. These unculturable spiral organisms were probably an incidental finding in patients presenting for upper gastrointestinal endoscopy, but it is not possible to say from this small series whether these organisms cause chronic active gastritis. The organism is helical, 3.5-7.5 microns long and 0.9 micron in diameter with truncated ends flattened at the tips, and up to 12 sheathed flagella 28 nm in diameter at each pole. It is proposed that this spiral bacterium should be called "Gastrospirillum hominis Gen.nov., Sp.nov."

Topographic association between active gastritis and Campylobacter pylori colonisation.

Abstract: One thousand biopsy specimens obtained from 10 sites in the stomachs of 50 patients were examined for the presence of active chronic gastritis and Campylobacter pylori. All 32 patients with active chronic gastritis at 234 out of 320 sites were positive for C pylori: 227 showed colonisation with C pylori by the Warthin-Starry stain; and 222 were positive by culture. C pylori was not found in 18 patients with inactive chronic gastritis or histologically normal mucosa. The area of C pylori colonisation was larger than the area of active chronic gastritis in 289 positive specimens on culture and 261 on staining, respectively, suggesting that C pylori colonisation may precede the development of active chronic gastritis. It is concluded that patchy distribution of active chronic gastritis and C pylori colonisation must be considered, particularly in serology or breath test studies where the histological examination serves as a reference. Furthermore, it may have important implications for the follow up of patients after antibacterial treatment. The topographic and specific association of C pylori and active chronic gastritis provides further evidence for the pathogenic role of C pylori in active chronic gastritis.

Association between invasiveness, inflammatory reaction, desmoplasia and survival in colorectal cancer.

Abstract: Five hundred and twenty seven colorectal carcinomas were reviewed histologically. A multivariate analysis (Cox) was used to test the prognostic importance of certain histological features (invasiveness, inflammatory reaction, and amount of fibrous tissue) at the tumour edge after allowance had been made for clinicopathological stage, tumour site, and histological type and grade. A poorly defined tumour border, lack of inflammatory reaction, and a pronounced fibrosis (desmoplasia) at the tumour edge were associated with unfavourable stage distributions, but each of these features also had an independent effect on prognosis.

Detection of T cells in paraffin wax embedded tissue using antibodies against a peptide sequence from the CD3 antigen.

Abstract: Rabbit polyclonal antibodies were raised against a proline rich, peptide sequence, comprising 13 amino acids, in the cytoplasmic domain of the CD3 epsilon chain. Immunoprecipitation experiments showed that this antibody preparation recognised the CD3 antigen on human T lymphoblasts. The antibody stained normal T cells strongly in tissue sections which had been fixed in formalin or Bouin's solution and embedded in paraffin wax. Its reactivity with T cell lymphoma, when evaluated on a series of 96 previously phenotyped cases, closely agreed with the results obtained on cryostat sections. These results indicate that the specific detection of T cells in routinely processed tissue biopsy specimens is now technically feasible on a wide scale in diagnostic laboratories using CD3 peptide antibodies, and they also suggest that in future the use of anti-peptide antibodies may detect other lineage specific antigenic markers in paraffin wax sections.

Comparison of clinical and postmortem diagnosis of pulmonary embolism.

Abstract: The incidence of pulmonary embolism and the number of clinically missed diagnoses of it in necropsies carried out between 1960 and 1984 at this department were investigated. Pulmonary embolism primarily affects elderly people with serious underlying disease; in this study it was found more often in women. The incidence of pulmonary embolism (9% of all necropsies) was unchanged during the period studied. In contrast, pulmonary embolism as the "sole" cause of death increased (p less than 0.0005). Although most pulmonary emboli were the immediate cause of death, the clinical diagnosis was often missed (in 84% of all cases). Furthermore, such clinically missed diagnoses increased over the years (p less than 0.005), especially in patients with heart disease and cancer. Without necropsy there will be considerable underdiagnosis of pulmonary embolism, therefore providing a misleading figure in the death statistics for this often fatal disease.

Identification of Pseudomonas pseudomallei in clinical practice: use of simple screening tests and API 20NE.

Abstract: The API 20NE kit and a simple screening system involving Gram's stain, the oxidase reaction, colistin and gentamicin resistance, and colonial characteristics on a differential agar medium, were used to test 400 strains of Pseudomonas pseudomallei. The API kit identified 390 (97.5%) strains correctly on first testing and all but one of the remainder on second testing. Only one strain was initially misidentified (as Ps cepacia). The screening system was 100% accurate in identifying Ps pseudomallei. In non-endemic areas the API 20NE kit may be used to identify sporadic imported strains of Ps pseudomallei. Such kits may also help to delineate the geographical distribution of melioidosis. In endemic areas the screening tests described offer a cheap, simple, and accurate means of presumptively identifying Ps pseudomallei from clinical specimens.

Jejunal enteropathy associated with human immunodeficiency virus infection: quantitative histology.

Abstract: Jejunal biopsy specimens from 20 human immunodeficiency virus (HIV) positive male homosexual patients were analysed and compared with those of a control group to determine whether the abnormalities were caused by the virus or by opportunistic infection. The degree of villous atrophy was estimated with a Weibel eyepiece graticule, and this correlated strongly with the degree of crypt hyperplasia, which was assessed by deriving the mean number of enterocytes in the crypts. The density of villous intraepithelial lymphocytes fell largely within the normal range, either when expressed in relation to the number of villous enterocytes or in relation to the length of muscularis mucosae. Villous enterocytes showed mild non-specific abnormalities. Pathogens were sought in biopsy sections and in faeces. Crypt hyperplastic villous atrophy occurred at all clinical stages of HIV disease and in the absence of detectable enteropathogens. An analogy was drawn between HIV enteropathy and the small bowel changes seen in experimental graft-versus-host disease. It is suggested that the pathogenesis of villous atrophy is similar in the two states, the damage to the jejunal mucosa in HIV enteropathy being inflicted by an immune reaction mounted in the lamina propria against cells infected with HIV.

Botulism. The Organism, Its Toxins, The Disease

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Proliferative activity in endometrial stromal granulocytes throughout menstrual cycle and early pregnancy.

Abstract: The proliferative activity in endometrial stromal granulocytes was studied using two approaches. Firstly, mitotic activity was studied in paraffin wax embedded sections of normal non-pregnant endometrium and early pregnancy decidua stained with phloxine-tartrazine. Secondly, the monoclonal antibody Ki67 was applied to cryostat sections of similar tissues. Endometrial stromal granulocytes were identified by their labelling with NKH1, Dako T11, UCHL1 or Dako-LC. The percentage of cases in which endometrial stromal granulocytes showed mitosis was 25%, 75%, 86%, and 93%, respectively in proliferative, early secretory, mid secretory, and late secretory phases, and 14% in early decidua. There were at most one or two endometrial stromal granulocytes in mitosis per 10 high power fields. Double labelled cells were present in small numbers in proliferative endometrium and in moderate numbers in secretory endometrium. Only a few cells in early decidua double labelled with Ki67/T11; moderate numbers of cells double labelled with Ki67/Dako-LC. It is concluded that proliferative activity does occur in endometrial stromal granulocytes and is particularly prominent in the late secretory phase.

Toxoplasmosis in heart and heart and lung transplant recipients.

Abstract: Of the first 250 heart and 35 heart and lung transplant recipients at Papworth Hospital, Cambridge, who survived for more than one month after transplantation, 217 heart and 33 heart and lung patients were investigated serologically for evidence of Toxoplasma gondii infection. Six patients acquired primary T gondii infection, most probably from the donor organ. Five patients experienced T gondii recrudescence, two of whom had recovered from primary infection a few years earlier. Two patients died from primary T gondii infection and the severity of symptoms in the other patients with primary infection was related to the amount of immunosuppressive treatment. Prophylaxis with pyrimethamine (25 mg a day for six weeks) was introduced for T gondii antibody negative transplant recipients who received a heart from a T gondii antibody positive donor after the first four cases of primary toxoplasmosis. Of the seven patients not given pyrimethamine, four (57%) acquired primary T gondii infection. This compared with two of the 14 patients (14%) given prophylaxis.

Fatal head injury in children.

Abstract: A comprehensive neuropathological study was undertaken on 87 children aged between 2 and 15 years with fatal head injuries to identify those features which occurred at the time of head injury (fractured skull, contusions, intracranial haematoma and diffuse axonal injury) and those which were subsequently produced by complicating processes (hypoxic brain damage, raised intracranial pressure, infection and brain swelling). The types of brain brain damage identified were remarkably similar to those seen in adults. The only difference was the prevalence of diffuse brain swelling in children.

Diurnal variations in serum biochemical and haematological measurements.

Abstract: Twenty five biochemical and haematological measurements were determined on nonfasting blood and serum samples collected between 9 am and 7 pm from a representative group of 7685 British middle-aged men. Most measurements showed significant diurnal variations, but only for bilirubin, phosphate, and triglyceride did time of day account for more than 5% of the between subject variance. Serum bilirubin concentrations showed a pronounced downward trend in the afternoon, the mean value after 6 pm being 30% lower than the mean value in the morning. Mean serum triglyceride and phosphate concentrations increased steadily through the day. Mean concentrations of potassium, haemoglobin, and haematocrit and red cell count were higher in the morning, while urea and creatinine concentrations and white cell count had higher means in the afternoon. Glucose showed a pattern consistent with short term response to meals. The effects of these diurnal trends on routine use of biochemical tests needs careful consideration, and a greater understanding of their biological mechanisms is required.

Distribution of glutathione S-transferase isoenzymes in human kidney: basis for possible markers of renal injury.

Abstract: To determine whether the tissue distribution of glutathione S-transferase (GST) isoenzymes could define the precise nature of renal injury, 13 adult kidneys were studied, using specific antibodies raised against purified isoenzymes Basic GST stained strongly proximal convoluted tubules and some medullary tubules; acidic GST stained strongly distal convoluted tubules and medullary tubules; neutral GST stained similarly to acidic GST, but weaker, and microsomal GST stained glomerular and interstitial endothelium and collecting ducts deep in the medulla, although there was considerable variation in staining intensity among cases It is suggested that the measurement of these isoenzymes in serum and urine may help to elucidate the localisation of tissue damage, which may be particularly valuable in patients with cyclosporine toxicity following renal transplantation

Campylobacter pylori infection in biopsy specimens of gastric antrum: laboratory diagnosis and estimation of sampling error.

Abstract: Campylobacter pylori infection was sought in 382 consecutive patients referred for upper gastrointestinal endoscopy. Five antral biopsy specimens were taken from each patient: one was inserted into a CLO-test to detect the urease activity of C pylori, two were sent for histological analysis where multiple sections were stained by the Warthin-Starry silver method, and two were sent for microbiological evaluation by Gram stain and culture. A patient was deemed to be infected when C pylori was cultured or seen in either the histological sections or the Gram stain of the biopsy smear. One hundred and seventy four (46%) patients were infected. Culture, Gram stain, histological examination and the CLO-test showed sensitivities of 92%, 87%, 93% and 90%, respectively. In 27 (15%) infected patients an uneven distribution of C pylori was seen between samples in the biopsy pair sent for histology. Examination of multiple sections stained with Warthin-Starry silver was more sensitive at detecting infection (93%) than examination of multiple sections from only one biopsy specimen (84%). Fifty seven of 80 patients, biopsied a median seven days (range 5 to 55) after completing colloidal bismuth subcitrate treatment, were still infected with C pylori. There was no decrease in the sensitivities of the above tests to detect infection after treatment. It is concluded that at least two antral biopsy specimens should be examined when attempting to diagnose C pylori infection by histological methods.

Cytomegalovirus infection in gastrointestinal tracts of patients infected with HIV-1 or AIDS.

Abstract: All gastrointestinal tract biopsy specimens from 190 patients positive for HIV-1 or with AIDS were reviewed to assess the prevalence of cytomegalovirus (CMV) infection, morphology of infected cells, and the associated histopathological features. Eighteen patients (10 (7.7%) of 129 HIV antibody positive and eight (13.1%) of 61 with AIDS) had CMV identified in 35 biopsy specimens from the following sites: oesophagus (n = 3); stomach (n = 6); small intestine (n = 4); colorectum (n = 18) and perianal area (n = 4). Eleven patients had CMV alone as the potential cause of symptoms and in seven there were coexistent pathogens or Kaposi9s sarcoma. The appearance and type of infected cells at different sites was highly variable. Immunocytochemical techniques and electron microscopic examination were performed to confirm the presence of CMV antigen and CMV virus particles and to exclude the possibility of an adenovirus producing similar cytopathic changes. It is important to recognise the different morphological forms of infected cells, and the use of immunocytochemical techniques is recommended in patients at risk for CMV or in whom CMV infection is suspected.

Prevalence of pulmonary embolism at necropsy in patients with cancer.

Abstract: The series studied comprised 6197 patients who had died of or who had cancer at death and represents all patients with cancer from 21,530 necropsies performed at this department from 1960-84 Pulmonary embolism was significantly more common among cancer patients than in those with non-neoplastic diseases Among those palliatively treated, patients with ovarian cancer, cancer of the extrahepatic bile duct system, and cancer of the stomach had the highest prevalence of pulmonary embolism (346%, 317%, and 152%, respectively) Necropsy patients with cancer of the oesophagus and larynx, together with leukaemia, myelomatosis, and malignant lymphoma had the lowest prevalence (0-56%) Palliatively treated cancers in organs of the peritoneal cavity had a significantly higher incidence than all other cancers combined Cancer of the peritoneal cavity may impede venous drainage from the lower limbs and thus be an important factor in the onset of deep calf vein thrombosis and pulmonary embolism It is concluded that cancer represents an increased risk factor for onset of pulmonary embolism, in particular in patients with ovarian cancer and cancer of the extrahepatic bile duct system

Pathology of tropical appendicitis.

Abstract: Over the past 25 years, 2921 appendicectomies were performed at this hospital. All were subjected to routine histopathological examination. In 95% of cases, histopathological examination did not add any further information but in 153 (5%) cases, clinically important pathological findings were detected for the first time. Seventy (2.3%) specimens showed typical evidence of tuberculosis. Parasitic infestation was detected in 75 (2.5%), including enterobiasis (1.4%), amoebiasis (0.5%), ascariasis (0.5%), ascariasis with trichuriasis (0.05%), and taeniasis (0.05%). Other lesions found were mucocele (0.1%) and carcinoid tumour (0.1%). It is concluded that routine histopathological examination of all appendicectomy specimens should be performed to avoid missing any clinically important and treatable condition.

Leukaemic phase of mantle zone (intermediate) lymphoma: its characterisation in 11 cases.

Abstract: Sixteen patients presented with B cell leukaemia (white cell count 26-269 x 10(9)/l) which could not be classified as chronic lymphocytic (CLL), prolymphocytic leukaemia, or follicular lymphoma in leukaemic phase Eleven patients (10 men, one woman) corresponded histologically to intermediate (INT) or mantle zone lymphoma, and five, with less well defined features, were designated small lymphocytic lymphoma with cleaved cells The blood films showed a pleomorphic picture with lymphoid cells of predominantly medium size with nuclear irregularities and clefts The membrane phenotype of the circulating cells showed strong immunoglobulin staining and reactivity with CD5 and FMC7 in all cases tested; CD10 was positive in six out of nine cases The membrane phenotype of two of the five cases of small lymphocytic lymphoma was close to those of B-CLL and three resembled INT lymphoma Bone marrow trephine biopsy specimens showed a diffuse pattern of infiltration in INT lymphoma The median survival of these patients was less than two years, suggesting that a leukaemic presentation is associated with poor prognosis By combining data from histology, membrane markers, and peripheral blood morphology, the leukaemic phase of typical INT lymphoma can be defined in most cases

Clinical importance of squamous metaplasia in invasive transitional cell carcinoma of the bladder.

Abstract: One hundred cases of transitional cell carcinoma of the bladder were studied to determine whether squamous metaplasia and other histological features within the bladder can be of value in predicting outcome of treatment with radiotherapy. Sixty cases showed the changes of squamous metaplasia, and of this group 46 (78%) failed to respond to radiotherapy. A significant response rate of 90% was seen in the 40 tumours without squamous metaplasia. It is concluded that transitional cell carcinomas of the bladder showing squamous metaplasia are mainly resistant to radiotherapy and alternative treatment methods should be sought.

Interphase cytogenetics using biotin and digoxigenin labelled probes I: relative sensitivity of both reporter molecules for detection of HPV16 in CaSki cells.

Abstract: This study was undertaken to develop technology for the detection of nucleic acid using two different DNA probe reporter molecules, the ultimate aim being to differentially label two nucleic acids within the same nucleus. Digoxigenin and biotin were used to label DNA probes. The absolute and relative sensitivity of digoxigenin and biotin labelled DNA probes for detecting integrated human papilloma virus 16 (HPV16) was investigated in CaSki cells by non-isotopic in situ hybridisation (NISH). Several methods for the detection of labelled probes were also investigated. The optimal sensitivity of digoxigenin labelled probe was equivalent to that of biotin when alkaline phosphatase was used as the final detector. The median number of discrete viral signals discernible in each cell with the most sensitive detection system was seven to eight with both labelled probes. The average number of HPV16 genomes in each CaSki cell, derived by dot blot hybridisation, was about 270. The calculated absolute sensitivity of NISH for viral detection in this system is complex because of variation of signal size and number. Nevertheless, one signal per nucleus equates to as little as 30 to 40 viral copies, and probably much less. The ability to distinguish up to 15 discrete signals with both digoxigenin and biotin labelled probes in the nuclei of CaSki cells indicates that these methods will be useful in interphase cytogenetics in material routinely fixed in aldehyde.

Aspergillosis of the nose and paranasal sinuses.

Abstract: Fulminant aspergillosis was diagnosed on nasal biopsy in a 49 year old man who had features of an aspergilloma. Further postmortem examination of this area was performed and the results were contrasted with the histological features of other Aspergillus infections. The nasal biopsy specimen and postmortem examination showed infiltrating Aspergillus hyphae with tissue necrosis and little inflammatory response. The hyphae were easily seen with routine stains. This contrasts with the findings in invasive aspergillosis where there is fibrosis and a granulomatous response to the Aspergillus hyphae. The hyphae are seen in giant cells using fungal stains. In the saprophytic infections aspergilloma and allergic Aspergillus sinusitis there is no tissue invasion or destruction. Aspergillus infections of the nose and paranasal sinuses often require biopsy for accurate diagnosis. As treatment varies pathologists need to be able to distinguish the different patterns of infection.

Clinical importance of DNA content in rectal cancer measured by flow cytometry.

Abstract: The DNA content of 369 rectal cancers was measured by flow cytometry. One hundred and four (28%) were diploid, 252 (68%) were aneuploid, and 13 (3.5%) were tetraploid. Diploid cancers were associated with an improved 5 year survival (p less than 0.001) and were more likely to present at an early stage. DNA content, however, did not confer independent prognostic information in a Cox model based on four discrete pathological variables. Patients were classified by a new system of prognostic grouping and those with a very good or a very poor outlook were removed leaving 137 prognostic group III patients. No further substratification of this group by DNA content or by four additional pathological variables could be achieved. As the new prognostic system is not improved by the addition of ploidy, routine adoption of flow cytometry in the assessment of rectal cancer cannot be recommended.