The use of Raman spectroscopy to identify and characterize transitional cell carcinoma in vitro

OBJECTIVE

To determine whether Raman spectroscopy can be used to differentiate between normal, inflammatory and malignant bladder pathologies in vitro, and secondly if it can used to grade and stage transitional cell carcinoma (TCC).

MATERIALS AND METHODS

In all, 1525 Raman spectra were measured from 75 bladder samples comprising normal bladder, cystitis, carcinoma in situ (CIS), TCC and adenocarcinoma. Multivariate analysis was applied to the spectral dataset to construct diagnostic algorithms; these were then tested for their ability to determine the histological diagnosis of each sample from its Raman spectrum.

RESULTS

The diagnostic algorithms could be used to accurately differentiate among the pathological groups, in particular, a three-group algorithm differentiated among normal bladder, cystitis and TCC/CIS with sensitivities and specificities of > 90%. Algorithms could also accurately characterize TCC in terms of splitting them into low (G1/G2) or high (G3) grade and superficial (pTa) or invasive (pT1/pT2) stage.

CONCLUSION

Raman spectroscopy can be used to accurately identify and grade/stage TCC in vitro. The technique therefore shows promise for use as an objective method to assist the pathologist in assessing bladder pathologies. Raman spectroscopy also has potential to provide immediate pathological diagnoses during surgical procedures. Following the promising results of this in vitro study, in vivo cystoscopic studies are planned.

The use of Raman spectroscopy to identify and grade prostatic adenocarcinoma in vitro

Raman spectroscopy is an optical technique, which provides a measure of the molecular composition of tissue. Raman spectra were recorded in vitro from both benign and malignant prostate biopsies, and used to construct a diagnostic algorithm. The algorithm was able to correctly identify each pathological group studied with an overall accuracy of 89%. The technique shows promise as a method for objectively grading prostate cancer.

The significance of cagA(+) Helicobacter pylori in reflux oesophagitis

BACKGROUND

Helicobacter pylori is a gastroduodenal pathogen associated with ulceration, dyspepsia, and adenocarcinoma. Recent preliminary studies have suggested that H pylori may be protective for oesophageal adenocarcinoma. In addition, strains of H pylori identified by the presence of the cytotoxin associated gene A (cagA) are shown to have a significant inverse association with oesophageal adenocarcinoma. Given that cagA(+) H pylori may protect against oesophageal carcinoma, these strains may be protective for oesophagitis, a precursor of oesophageal carcinoma.

AIMS

The aim of this study was to investigate the association between cagA(+) H pylori and endoscopically proved oesophagitis.

PATIENTS

The study group included 1486 patients attending for routine upper gastrointestinal tract endoscopy.

METHODS

At endoscopy the oesophagus was assessed for evidence of reflux disease and graded according to standard protocols. Culture and histology of gastric biopsy specimens determined H pylori status. The prevalence of cagA was identified by an antibody specific ELISA (Viva Diagnostika, Germany).

RESULTS

H pylori was present in 663/1485 (45%) patients and in 120/312 (38%) patients with oesophagitis. Anti-CagA antibody was found in 499/640 (78%) H pylori positive patients. Similarly, anti-CagA antibody was found in 422/521 (81%) patients with a normal oesophagus and in 42/60 (70%) with mild, 24/35 (69%) with moderate, and 11/24 (46%) with severe oesophagitis. The risk of severe oesophagitis was significantly decreased for patients infected with cagA(+) H pylori after correction for confounding variables (odds ratio 0.57, 95% confidence interval 0.41-0.80; p=0.001).

CONCLUSIONS

These results suggest that infection by cagA(+) H pylori may be protective for oesophageal disease.

A comparison of six commercial kits for Helicobacter pylori detection

The British Society of Gastroenterologists suggests that dyspeptic patients under 45 years of age should be screened serologically for Helicobacter pylori infection, to reduce endoscopy workload. We have compared the sensitivity, specificity, and predictive value of six commercial serological kits intended for pre-endoscopy screening for H. pylori with histopathology and culture in 82 dyspeptic patients, 35 of whom were H. pylori positive. The kits' sensitivities were as follows: Bio-Rad GAP 100%, Helico-G 100%, Premier 97%, and Pyloriset EIA-G 94%. Poor specificity of the ELISA kits--Bio-Rad GAP 67%, Helico-G 67%, Premier 85%, and Pyloriset EIA-G 76%--was due to previous treated or cleared H. pylori infection. Allowing for previously documented H. pylori infection or peptic ulcer improved specificity--Bio-Rad GAP 84%, Helico-G 84%, Premier 100%, and Pyloriset EIA-G 90%. The Pyloriset Dry latex kit had a higher specificity (86%) but a lower sensitivity (75%) than the Oxoid latex kit (specificity 70%, sensitivity 94%). The qualitative Premier Launch kit had the best overall results (and was the easiest ELISA to perform). Reliable serological diagnosis of H. pylori is now suitable for screening dyspeptic patients.

Preservation of gastric antral mucus is associated with failure of eradication of Helicobacter pylori by bismuth, metronidazole and tetracycline

METHODS

Forty-three patients positive for Helicobacter pylori by histology and culture of antral biopsies (n = 40) or histology alone (n = 3) were investigated. They received either regimen 1--tripotassium dicitrato bismuthate 120 mg q.d.s. and tetracycline 250 mg q.d.s. for 4 weeks, with metronidazole 200 mg q.d.s. for the first 2 weeks, or regimen 2--omeprazole 20 mg b.d., amoxycillin 500 mg t.d.s., tetracycline 500 mg q.d.s. each for 3 weeks. Gastric antral biopsies were scored (0-3) histologically for mucus depletion, polymorphonuclear and mononuclear cell infiltrate. H. pylori eradication was assessed by biopsy and culture 1 month after the cessation of treatment.

RESULTS

With regimen 1, pre-treatment mucus depletion was significantly higher where eradication was successful (median score 2) compared to where it was not (median score 1, P < 0.01); there were no differences in the scores for polymorphonuclear or mononuclear cell infiltrates. In patients receiving regimen 2, there were no differences in either mucus depletion or polymorphonuclear or mononuclear cell infiltrate, between those where eradication was successful and those where it was not. Metronidazole minimum inhibitory concentrations rose when eradication with regimen 1 was unsuccessful (median before 0.19 mg/L, median after treatment 16 mg/L; P = 0.04).

CONCLUSION

Pre-treatment mucus depletion is identified as a factor affecting H. pylori eradication. Preservation of mucus may facilitate acquisition of metronidazole resistance.

Long-term follow up of patients with gastritis associated with Helicobacter pylori infection

The aim of this study was to evaluate the long-term prognosis for patients suffering from gastritis associated with Helicobacter pylori infection, and in particular the proportion of cases progressing to peptic ulcer. The study was carried out in one urban general practice. One hundred and three patients who had presented with dyspepsia over the 1973-80 period and who were found to have a macroscopically normal endoscopy were reassessed between seven and 14 years later. Gastric antral biopsies had been taken routinely at endoscopy and were subsequently re-examined for the presence of H pylori. The patients' medical records were examined to establish their consulting rates over the follow-up period and whether they suffered from any other medical conditions. Patients were interviewed to assess the course of their dyspeptic symptoms. Comparison of patients who were unequivocally H pylori positive with those who were negative revealed no significant differences in the consultation rate for gastroenterological symptoms, in the proportion of patients referred to a hospital consultant or for further gastroenterological investigations or in the proportion reporting that their symptoms had improved. However, a statistically highly significant relationship was found between H pylori infection and hypertension. The results of this study have shown that there is a good prognosis for non-ulcer dyspepsia whether or not H pylori infection is present. The association between H pylori gastritis and hypertension clearly merits further investigation.

Detection of Campylobacter pylori by the biopsy urease test: an assessment in 1445 patients

The presence of C pylori infection was determined in 1445 patients undergoing upper gastrointestinal endoscopy over a 12 month period. The presence of C pylori was detected in gastric mucosal biopsy specimens by the biopsy urease test, microscopy (Gram stained smears and histology) and culture. Two media were used for the biopsy urease test: Christensen's urea broth (for the first 600 patients) and the Christensen's urea broth modified by increasing the concentration of phenol red and omitting the nutrients, glucose and peptone (for the remaining patients). Both the Christensen's urea broth and modified urea broth were almost 100% specific when compared with detection of C pylori by Gram, culture and histopathology. The modified broth was more sensitive (96% sensitivity compared with culture) than the Christensen's broth (92% sensitivity) but this difference was not statistically significant. The modified broth gave significantly more positive results (58%) in less than 30 minutes than the Christensen's broth (48%). Seventy four per cent of positive results were available in less than two hours. Specimens from patients with extensive C pylori infection gave more rapid results: 86% of specimens that yielded a profuse growth of C pylori and 76% that contained numerous organisms on histological sections had a positive urease test in less than one hour. There was no significant difference between the specificity and sensitivity of our modified urea broth and the other modified broths described in the literature. This test is a cheap and rapid alternative to the diagnosis of C pylori by Gram stained smears or culture.

New spiral bacterium in gastric mucosa

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."

Proliferative glomerulonephritis in mice given intravenous Corynebacterium parvum

Mice given a killed suspension of Corynebacterium parvum (C.p.) developed nephritis as part of an immune complex disease. The nephritis was dose-related. After a single dose of 70 microgram (a human-equivalent dose) or of 466 microgram there was a mesangiopathic glomerulonephritis and after repeated human-equivalent doses there was a mesangiocapillary glomerulonephritis. Antibodies to C.p. increased and circulating immune complexes were detected. Mice receiving repeated doses also developed an arteritis. Study of this model may help in the understanding of human immune complex disease and the pathogenesis of glomerulonephritis.

In vitro fixation of guinea pig complement by renal biopsies

The in vitro fixation of heterologous complement by cryostat sections of human renal biopsy material was studied to determine the mechanism of complement activation. Various types of guinea pig sera with different parts of the complement system inhibited were used, the fixation of complement being detected by direct immunofluorescence. Cases of idiopathic focal nephritis with mesangial IgA (mesangial IgA disease), Henoch-Schönlein purpura (HSP) and mesangio-capillary glomerulonephritis (MCGN) fixed complement by the alternative pathway alone and in systemic lupus erythematosus (SLE) both the classical and alternative pathways were involved. Only one of the seven cases of membranous glomerulonephritis fixed complement and this was by the classical pathway. After prior treatment with C3b inactivator, the in vitro complement fixation in mesangial IgA disease, HSP and MCGN was greatly reduced. In SLE it was slightly reduced and in membranous glomerulonephritis there was no change. This is a convenient method of studying the biological properties of complexes which is believed to reflect the in vivo behaviour of the tissue deposited complex.

"Blue bodies" in a case of cryptogenic fibrosing alveolitis (desquamative type) an ultra-structural study

A patient with cryptogenic fibrosing alveolitis, with both mural and desquamative features, had two lung biopsies at the times of coronary artery surgery. These lung specimens were studied, using light and electron microscopy, with immunofluorescence techniques and electron microanalysis. In addition to the typical changes of cryptogenic fibrosing alveolitis previously reported, we found "blue-staining bodies" within alveolar macrophages and giant cells. These bodies were 15--25 micrometer in diameter with an iron rich outer rim and core of connective tissue mucin--possibly chondroitin sulphate or dermatan sulphate. It seems unlikely that these "blue bodies" were due to fibreglass dust to which the patients had had a trivial exposure, but their exact nature and significance remains unclear.

Renal histology and immunopathology in distal renal tubular acidosis

Renal biospy studies are reported from 10 patients with distal renal tubular acidosis (DRTA). On the biopsies from 6 patients who had associated immunological abnormalities immunofluorescent studies for immunoglobulins, complement, and fibrin were performed. Interstitial cellular infiltration and fibrosis were common findings in patients with and without immunological abnormalities, and were usually associated with nephrocalcinosis and/or recurrent urinary infection. No immune deposits were demonstrated in association with the renal tubules. This study shows that DRTA in immunologically abnormal patients is not caused by tubular deposition of antibody or immune complexes. The possibility of cell mediated immune damage is discussed.

Blue naevus of the cervix: report of two cases and review of the literature

Two cases are described of blue naevi occurring in the uterine cervix. These showed a histological appearance identical to that seen in the commoner cutaneous examples. Electron microscopy of both lesions showed the presence of melanosomes in the dendritic cells. No Schwann cell elements were identified. Previous reports of cases are reviewed and discussed.

Anal neurofibrosarcoma treated with fast neutron irradiation

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Acute pleurisy in sarcoidosis

A 47-year-old white man with sarcoidosis presented with a six-week history of acute painful pleurisy. On auscultation a loud pleural rub was heard at the left base together with bilateral basal crepitations. The chest radiograph showed hilar enlargement as well as diffuse lung shadowing. A lung biopsy showed the presence of numerous epithelioid and giant-cell granulomata, particularly subpleurally. A patchy interstitial pneumonia was also present. He was given a six-month course of prednisolone, and lung function returned to normal.

Mesangio-capillary glomerulonephritis associated with Q-fever endocarditis

A patient with nephrotic syndrome and Q-fever endocarditis (confirmed serologically and ultrastructurally) was found to have mesangio-capillary glomerulonephritis with parietal deposits of C3 and IgM and some IgM in the mesangium. Elution studies showed that IgM antibodies reactive against insoluble Coxiella antigens were present in the kidney. Review of the literature suggests that this type of immune complex nephritis may be associated with Q-fever. Possible reasons for the variability of the nephritis associated with infective endocarditis are discussed.