Aims-To investigate the eVects of slide storage on immunohistochemical staining, since recent reports have indicated that storage of unstained paraYn slides for up to 12 weeks may lead to false negative immunostaining of tumour markers. Methods-11 antibodies (anti-cytokeratin, epithelial membrane antigen (EMA), vimentin, smooth muscle actin, PS100, chromogranin, CD45, CD20, CD3, CD30, and oestrogen receptor (OR)) were tested on unstained paraYn slides of breast carcinomas, lymphomas, and neuroendocrine tumours that had been stored for three to 10 years. All the paraYn blocks were recut less than one week before immunostaining. Immunostainings of years old slides were compared with those of recent slides in at least five cases for each antibody. For three antibodies (antichromogranin, anti-CD3, and anti-OR) we also tested one year old and three months old slides. Results-Intensity of staining on years old slides was strikingly reduced for chromogranin and CD3 in several cases and was slightly stronger for vimentin. In some cases a significant decrease of OR positivity was observed after three months storage, and a complete loss of OR immunostaining after 12 months. No significant diVerence was noted with the other antibodies. Conclusions-Immunohistochemical detection of some antigens located either in the nucleus, in the cytoplasm, or on the cytoplasmic membrane could be impaired by storage of paraYn slides as short a time as three months. One should be cautious of doing retrospective immunohistochemical studies on stored unstained slides.

Eighteen patients infected with human immunodeficiency virus and with chronic unexplained diarrhea were prospectively studied to investigate the prevalence and clinical and biologic features of intestinal microsporidiosis. All patients underwent extensive evaluation for bacterial, viral, and parasitic pathogens. Enterocytozoon bieneusi was found in 9 patients (50%; 95% confidence interval, 27-73) in stools and duodenal and jejunal biopsies. In 8 patients, it was the sole pathogen found. Other pathogens were also isolated from the intestinal tracts of 4 patients, but diarrhea remained unexplained in 6. Patients with intestinal microsporidiosis had significantly lower mean Karnofsky scores (69.4 vs. 85.5, P = .009), CD4 cell counts (18.6 vs. 209.8/microL, P = .02), and D-xylose absorption tests (0.13 vs. 0.36 g/L, P < .001) than did patients without intestinal microsporidiosis. Intestinal microsporidiosis appears to be a frequent cause of unexplained chronic diarrhea in patients with AIDS and is associated with diminished D-xylose absorption.

Although FS reliability was good, disparities were noted in the assessment methods used by local pathologists. The protocol for FS determination was not followed routinely, with the result that the FS was often overestimated. Germinal centre-like structures, which predict lymphoma, showed good reliability but were inconsistently reported.

BackgroundEvaluating lymphocytic infiltration of minor salivary gland biopsy in primary Sjögren’s syndrome is challenging. We developed and evaluated a digital method for quantifying B and T lymphocytes in whole minor salivary gland biopsy slides.MethodsMinor salivary gland biopsies were immunostained with anti-CD20/anti-CD3 antibodies using red/brown chromogens. Slides were digitised and spliced into mosaics of smaller JPEG format images in which red and brown pixels were counted. ImageJ Cell counter was used for validation. Agreement between the digital and manual methods was evaluated using Bland-Altman plots and the interclass correlation coefficient. External validation relied on the Chisholm-Mason, Tarpley, and focus-score methods.ResultsOf 62 minor salivary gland biopsy slides, 61.3 % had a Chisholm-Mason grade ≥ III or a focus score ≥1. The number of pixels correlated well with manual cell counts (r = 0.95 for red pixels vs. B cell count and r = 0.91 for brown pixels vs. T cell count). Interclass correlation coefficients between digital and manual counts were excellent (0.92 for B/T cells). B-cell proportion showed a significant positive correlation with the focus score (Spearman’s coefficient 0.463, p < 0.0001). Median B-cell proportion was lower in minor salivary gland biopsies with Chisholm grades I–II (2.5 % (0.2–13.9)) than III–IV (30.0 % (15.5–45.2)) and increased with Tarpley’s class (1, 2.2 % (0.2–6.6); 2, 27.2 % (13.0–38.9); and 3–4, 48.5 % (29.4–56.4); p < 0.001 for all comparisons). Minor salivary gland biopsy B-cell proportion was also significantly correlated with several markers of clinical and biological activity of the disease, especially with markers of systemic B-cell hyperactivation.ConclusionThe digital procedure proved accurate compared to the reference standard, producing reliable results for whole tissue sections.Trial registrationClinicalTrials.gov [NCT00740948]. Registered 22 August 2008.

The ureteral duplication is a relatively common malformation and usually has no pathologic consequences. On the contrary, congenital diverticula of the ureter are rare and often give rise to urinary complications. A double malformation combining left ureteral duplication and a congenital diverticulum of the right ureter is reported and discussed. This rare case illustrates one and the same malformational process arrested at different stages of development.