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D S A Sanders

Publications and source records attributed to D S A Sanders.

9 recordsLinked to original sources

The Warwick system of prospective workload allocation in cellular pathology--an aid to subspecialisation: a comparison with the Royal College of Pathologists' system.

BACKGROUND: Guidelines on staffing and workload for histopathology and cytopathology departments was published by the Royal College of Pathologists (RCPath) in July 2003. In this document, a system is provided whereby the workload of a cellular pathology department and individual pathologists can be assessed with a scoring system based on specialty and complexity of the specimens. A similar, but simplified, system of scoring specimens by specialty was developed in the Warwick District General Hospital. The system was based on the specimen type and suggested clinical diagnosis, so that specimens could be allocated prospectively by the laboratory technical staff to even out workload and support subspecialisation in a department staffed by 4.6 whole-time equivalent consultant pathologists. METHODS: The pathologists were asked to indicate their reporting preferences to determine specialist reporting teams. The workload was allocated according to the "prospective" Warwick system (based on specimen type and suggested clinical diagnosis, not affected by final diagnosis or individual pathologist variation in reference to numbers of blocks, sections and special stains examined) for October 2003. The cumulative Warwick score was compared with the "retrospective" RCPath scoring system for each pathologist and between specialties. Four pathologists recorded their time for cut-up and reporting for the month audited. RESULTS: The equitable distribution of work between pathologists was ensured by the Warwick allocation and workload system, hence facilitating specialist reporting. Less variation was observed in points reported per hour by the Warwick system (6.3 (range 5.5-6.9)) than by the RCPath system (11.5 (range 9.3-15)). CONCLUSIONS: The RCPath system of scoring is inherently complex, is applied retrospectively and is not consistent across subspecialities. The Warwick system is simpler, prospective and can be run by technical staff; it facilitates even workload distribution throughout the day. Subspecialisation within a small-sized or medium-sized department with fair distribution of work between pathologists is also allowed for by this system. Reporting times among pathologists were shown by time and motion studies to be more consistent with Warwick points per hour than with RCPath points per hour.

Cytodiagnosis↗

The outcome of surgery in fulminant Clostridium difficile colitis.

BACKGROUND: The clinical presentation of Clostridium difficile infection ranges from asymptomatic carriage, colitis with or without pseudomembranes, to fulminant colitis. Although not common, fulminant C. difficile colitis can result in bowel perforation and peritonitis with a high mortality rate. Colectomy is often indicated in these cases. METHODS: We retrospectively analysed the outcome of 14 patients who underwent surgery for fulminant C. difficile colitis in the period 1996-2003 in our Unit. RESULTS: The indications for surgery were systemic toxicity and peritonitis (n = 10), radiological and clinical evidence of progressive toxic colonic dilatation (n = 3) and progressive colonic dilatation with bowel perforation (n = 1). C. difficile infection as the cause of colitis was diagnosed pre-operatively in seven (50%) patients, six of whom underwent a total colectomy and one a right hemicolectomy. Overall mortality in our series was 35.7%. Total colectomy was associated with a lower mortality rate of 11.1% (1/9) when compared with left hemicolectomy was 100% (4/4) (P = 0.01). One patient who underwent a right hemicolectomy (on the basis of deceptively normal external appearance of the rest of the colon intra-operatively) survived after a prolonged hospital stay. CONCLUSIONS: Early or pre-operative microbiological diagnosis of C. difficile infection can be difficult in patients with a fulminant presentation. Those patients with C. difficile colitis, who develop signs of toxicity, peritonitis or perforation, should undergo a total colectomy as the operation of choice.

Adult↗

Subspecialisation in cellular pathology in the DGH setting: the Warwick experience.

A successful move towards subspecialised reporting in cellular pathology in the setting of a small to medium-sized district general hospital staffed by five consultant pathologists is described. This move has been facilitated by implementation of a prospective workload allocation system. Perceived benefits in service delivery and career progression are highlighted.

Cytodiagnosis↗

Mucosal integrity and barrier function in the pathogenesis of early lesions in Crohn's disease.

Crohn's disease aetiology is multifactorial and remains enigmatic. However, animal models show that disease heterogeneity is probable, in that more than one defective mucosal mechanism can produce the same clinical phenotype. For example, Crohn's-like lesions are reported after compromise of mucosal integrity per se in the presence of an intact immune system, through altered expression of mucosal adhesion molecules, such as cadherins and tight junction proteins, highlighting the importance of the mucosal barrier in the disease process. Key to mucosal damage is the trigger of an inflammatory cascade after luminal antigen processing, a role classically ascribed to M cells in the surface follicle associated epithelium. Direct luminal antigen sampling has recently been proposed, however, by extension of dendritic cell (DC) processes through the intact gut epithelium, and it follows that early mucosal damage could result from de novo lymphoid recruitment. Cytokines, such as tumour necrosis factor alpha (TNFalpha), are known to drive inflammation, but emerging data suggest additional important roles for TNFalpha influencing mucosal barrier efficacy by altering adhesion molecule expression, influencing epithelial apoptosis, and affecting tight junction functionality.

Cadherins↗

Dermatofibrosarcoma protuberans treated by micrographic surgery.

Dermatofibrosarcoma protuberans is an uncommon cutaneous tumour which rarely metastasises. However, local recurrence following apparently adequate surgical excision is well recognised, presumably as a result of sub-clinical contiguous growth, for which micrographically controlled excision would be a logical treatment. A retrospective study of all patients treated by micrographic surgery, from April 1995-March 2000, at a tertiary skin oncology centre. Twenty-one patients (11 males), age 14 to 71 years with dermatofibrosarcoma protuberans on the trunk (10 patients), groin (four), head and neck (four), and limbs (three) were treated. In 15 patients one micrographic layer cleared the tumour, and four were cleared with two layers. For one patient the second stage was completed by conventional excision guided by positive margins. Another patient with a multiply recurrent perineal dermatofibrosarcoma protuberans, not cleared in one area after two layers, died from a pulmonary embolus before total clearance could be achieved. There was no correlation between tumour size and lateral excision margin. No recurrence was observed during the follow-up, from 21 to 80 months, median 47 months. The study provides further support for micrographic surgery as the treatment of choice for dermatofibrosarcoma protuberans.

Adolescent↗

Progressive nodular histiocytosis in a child with a hypothalamic tumor.

We report a 13-year-old girl with multiple cutaneous histiocytic lesions, precocious puberty, growth hormone deficiency and a hypothalamic tumour. We conclude that she has progressive nodular histiocytosis, but this case illustrates the difficulty in differentiating the type II histiocytoses.

Adolescent↗

Multiple cutaneous plasmacytomas following an autologous peripheral stem cell transplant.

We describe the unusual development of multiple cutaneous plasmacytomas following treatment of IgA lambda myeloma with myeloablative therapy and a peripheral blood stem cell autograft. Cutaneous metastatic spread was evident despite bone marrow remission. Treatment with an autograft may have contributed to the cutaneous relapse.

Hematopoietic Stem Cell Transplantation↗

Aberrant P-cadherin expression is an early event in hyperplastic and dysplastic transformation in the colon.

BACKGROUND: Colorectal adenomatous and, probably, hyperplastic polyp development requires epithelial remodelling and stratification, with loss of E-cadherin expression implicated in adenoma formation. We have shown that P-cadherin, normally expressed in stratified epithelia and placenta, is aberrantly expressed in disturbed epithelial architecture associated with colitis. AIMS: (i) To investigate the role of P-cadherin in colonic polyp formation. (ii) To ascertain whether expression of P-cadherin is independent of or correlated with expression of its associated proteins--E-cadherin, beta-catenin, and gamma-catenin. (iii) To determine if P-cadherin is functional regarding catenin binding in polyps. METHODS: Expression and localisation of cadherins (E- and P-) and their associated catenins (beta- and gamma-) were determined in aberrant crypt foci (ACF), in polyps with hyperplastic morphology (hyperplastic polyps and serrated adenomas), and in adenomatous polyps by immunohistochemistry, western blotting, and mRNA in situ hybridisation. Assessment of cadherin-catenin binding was evaluated by co-immunoprecipitation. Adenomatous polyposis coli (APC) mutation was assessed in adenomatous polyps. RESULTS: P-cadherin was expressed from ACF through to hyperplastic and adenomatous polyps. Alterations in E-cadherin and catenin expression occurred later, with variant patterns in (i) ACF, (ii) hyperplastic polyps and serrated adenomas, and (iii) adenomatous polyps. P-cadherin present in adenomas was functional with regard to catenin binding, and its expression was independent of APC mutational status. CONCLUSIONS: P-cadherin is aberrantly expressed from the earliest morphologically identifiable stage of colonocyte transformation, prior to changes in E-cadherin, catenin, and APC expression/mutation. P-cadherin expression alone does not predict tissue morphology, and such expression is independent of that of associated cadherins and catenins.

Adenomatous Polyposis Coli↗