Patrick J. Dean
University of Tennessee Health Science Center
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Featured researches published by Patrick J. Dean.
The American Journal of Surgical Pathology | 1996
Lydia M. Makapugay; Patrick J. Dean
A clinical syndrome of chronic colitis unique to the sigmoid colon harboring diverticular was recently reported; its histopathological appearance has not been fully elucidated. In this study, the authors analyzed the clinical and pathological features of 23 patients (age range, 38-87 years; median age, 72 years) with diverticular disease-associated chronic colitis. Nineteen presented with hematochezia; four had abdominal pain. Colonoscopic visualization of the mucosa showed patchy or confluent granularity and friability affecting the sigmoid colon encompassing diverticular ostia. Colonic mucosae proximal and distal to the sigmoid were endoscopically normal. Mucosal biopsy specimens showed features of idiopathic inflammatory bowel disease that included plasmacellular and eosinophilic expansion of the lamina propria (100%), neutrophilic cryptitis (100%) with crypt abscesses (61%), basal lymphoid aggregates (100%), distorted crypt architecture (87%), basal plasmacytosis (61%), surface epithelial sloughing (61%), focal Paneth cell metaplasia (48%), and granulomatous cryptitis (26%). Concomitant rectal biopsies obtained in five patients demonstrated histologically normal mucosa. Fourteen patients treated with high-fiber diet or antibiotics or both improved clinically, as did nine patients administered sulfasalazine or 5-aminosalicylic acid. Five patients underwent sigmoid colonic resection, three for stricture with obstruction and two for chronic blood loss anemia. Among a control population of 23 age- and gender-matched patients with diverticular disease without luminal surface mucosal abnormality, none required resection during the same follow-up period. By Fishers exact test, a statistically significant difference in outcome for patients with and without colitis was detected (p = 0.049). In addition, three patients developed ulcerative proctosigmoiditis 6, 9, and 17 months after the onset of diverticular disease-associted colitis. The data indicate that diverticular disease-associated chronic sigmoid colitis expresses morphological features traditionally reserved for idiopathic inflammatory bowel disease. Its clinical and endoscopic profiles permit distinction from Crohns disease and ulcerative colitis. Patients with chronic colitis in conjunction with diverticula are at increased risk for sigmoid colonic resection. Diverticular disease-associated chronic colitis may also precede the onset of conventional ulcerative proctosigmoiditis in some cases.
The American Journal of Surgical Pathology | 1995
Daniel G. Deana; Patrick J. Dean
Ischemic colitis, a condition of middle-aged to elderly patients, occurs uncommonly in younger persons. In this study, we describe the clinical and pathological features of 18 young adults (mean age, 29 years; age range, 17–39 years) with spontaneous ischemic colitis, 17 of whom were women. All presented with abrupt onset of severe, cramping abdominal pain followed by hematochezia. Colonoscopic visualization of the mucosa showed segmental hyperemia, friability, and erosion affecting the distal transverse colon (three cases), splenic flexure (three cases), descending colon (five cases), and sigmoid (seven cases). Mucosal biopsy documented superficial ischemic necrosis in seven patients; 11 patients had fullthickness mucosal necrosis with regeneration. Colonic mucosa proximal and distal to the ischemic segment was endoscopically normal in all patients and histologically normal in the eight patients in whom biopsies were obtained. All patients recovered with supportive care. Median duration of illness was 2.1 days (range, 1–4 days). Ten women (59%) were using low-dose estrogenic oral contraceptive agents, compared with the 1988 national average of 18.5% oral contraceptive users among females aged 15 to 44 years. The calculated odds ratio yielded a greater than sixfold relative risk for the occurrence of ischemic colitis among oral contraceptive users. In addition, four women not currently on hormonal contraceptive therapy had a past history of oral contraceptive use: the three remaining women were taking estrogen as replacement therapy after oophorectomy. In one patient, documented reversible ischemic colitis recurred on resumption of oral contraceptive use; four women reported symptoms and signs of recurrent ischemia but did not seek further medical evaluation. Our data indicate that transient colonic ischemia represents a form of acute segmental colitis in young adults; before the 5th decade of life, spontaneous ischemic colitis is a disorder found almost exclusively in women and is associated with the clinical use of exogenous estrogenic agents.
The American Journal of Surgical Pathology | 2001
Laura W. Lamps; Kunapuli T. Madhusudhan; Joel K. Greenson; Robert H. Pierce; Nicole A. Massoll; Melissa C. Chiles; Patrick J. Dean; Margie A. Scott
Granulomatous appendicitis is an enigmatic entity. Purported causes include Crohns disease, foreign body reactions, sarcoidosis, and infectious agents; however, most cases remain idiopathic. Yersinia enterocolitica (YE) and Y. pseudotuberculosis (YP) have been implicated as causes of appendicitis, ileocolitis, and mesenteric adenitis. The authors examined the potential role of YE and YP in granulomatous appendicitis using histologic and molecular methods. Forty cases of granulomatous appendicitis were evaluated for histologic features including transmural inflammation, number and character of granulomas, and mucosal changes. Twort Gram, Grocott methenamine-silver (GMS), and Ziehl–Neelsen stains were evaluated, and polymerase chain reaction (PCR) analysis was performed to identify pathogenic YP and YE. Twenty-five percent (10 of 40) of the cases were positive for pathogenic Yersinia by PCR (four YE, four YP, and two with both species). Prominent histologic features included epithelioid granulomas with lymphoid cuffing, transmural inflammation with lymphoid aggregates, mucosal ulceration, and cryptitis. One Yersinia-positive case contained mural Gram-negative bacilli; fungal and acid-fast bacilli stains were all negative. Except for one culture-negative case, serologies and cultures were not done or results were unavailable. Two Yersinia-positive patients were diagnosed subsequently with Crohns disease, suggesting a possible relationship between the two entities. No other patients developed significant sequelae. YE and YP are important causes of granulomatous appendicitis, and Yersinia infection may mimic Crohns disease. No histologic features distinguish reliably between Yersinia species, or between Yersinia-positive and Yersinia-negative cases. Because special stains and cultures are often not diagnostic, PCR analysis is an excellent technique for the diagnosis of Yersinia.
The American Journal of Surgical Pathology | 1986
William M. Murphy; Patrick J. Dean; John A. Brasfield; Leslie Tatum
A prospective study of 386 consecutive transurethral prostatic resections from 383 patients with clinically benign glands was undertaken to determine the optimal sampling of chips required for the histologic detection of all clinically significant prostatic carcinomas. Cancers were graded according to two systems and staged by counting involved chips as well as estimating volume density. All Stage A2 prostatic carcinomas were detected by histologic examination of 6 g of randomly selected chips. Although additional tumors were detected in direct proportion to the amount of tissue examined, they were small, well-differentiated, Stage Al lesions. Histologic sampling of 12 g of randomly selected prostatic chips detected almost 90% of incidental carcinomas, including all clinically significant neoplasms.
Journal of Clinical Gastroenterology | 2010
Bergein F. Overholt; Patrick J. Dean; Joseph A. Galanko; Charles J. Lightdale
Background Photodynamic therapy (PDT) and radiofrequency ablation (RFA) are associated with high rates of complete eradication of Barrett esophagus (BE). However, if ablation were to induce fibrosis in the regenerated squamous epithelium, then postablation biopsies may not penetrate deeply enough to detect subsquamous intestinal metaplasia (SSIM) and, therefore, complete response rates could be over-estimated. Goals To assess the depth of esophageal biopsies from the squamous epithelium of ablation-naive controls and from the neosquamous epithelium of post-PDT and post-RFA patients to determine if prior ablation results in a reduced proportion of biopsies containing lamina propria (LP) as compared with controls. Study Review of archived esophageal specimens from a prospective multicenter cohort study (post-RFA) and 2 retrospective consecutive case series (ablation-naive controls, post-PDT). Setting Eight US centers and 1 US gastrointestinal pathology laboratory. Patients Ablation-naive controls with GERD, dyspepsia, and/or BE. Post-PDT and post-RFA BE patients with biopsies more than 6 months after achieving complete eradication of BE. Interventions Review of endoscopic biopsies from ablation-naive controls, post-PDT patients, and post-RFA patients. Main Outcome Measurements One GI pathology lab processed all tissue and slides. One expert GI pathologist, blinded to cohort, graded the depth of each esophageal specimen as: partial epithelium, full epithelium, LP, muscularis mucosae, or submucosa. Each specimen was also evaluated for SSIM. Results There were 82 patients [ablation-naive (12), post-PDT (10), post-RFA (60)] with 899 biopsy specimens. The proportion of specimens containing “LP or deeper” was similar between groups: ablation-naive (88%), post-PDT (88%), post-RFA (91%) (P>0.05). No SSIM was detected in any group. Conclusions There is no difference in esophageal biopsy depth between ablation-naive squamous epithelium and post-PDT/post-RFA neo-squamous epithelium, thus refuting the concern of ablation-induced mucosal resistance to procurement of adequate biopsy specimens. Most biopsies (88% to 91%) from both ablation cohorts were deep enough to detect SSIM, in that they included “LP or deeper.”
Gastroenterology | 1986
Larry W. Schmidt; Patrick J. Dean; Robin T. Wilson
Superficially invasive squamous cell carcinoma of the esophagus, defined as carcinoma with invasion limited to the mucosa or submucosa regardless of the presence of lymph node metastasis, is being increasingly recognized. We found 7 cases (13%) of this entity among 54 cases of esophageal squamous cancer resected between 1981 and 1984 in Memphis, Tennessee. Three patients presented with dysphagia, 1 with odynophagia, and 3 with nonesophageal symptoms. Barium esophagram demonstrated the tumor in 2 cases. Endoscopically, four lesions were identified as tumor and three were attributed to inflammation. Two tumors were nodules, three were plaques, one was polypoid, and one was grossly inapparent. Two patients died without evidence of disease. One patient with lymph node metastasis died of disease at 17 mo. Four patients have survived from 16 to 52 mo after resection without evidence of disease. Timely diagnosis of this early form of esophageal neoplasia provides the opportunity for curative resection.
Cancer Research | 1991
Patricia L. Blount; Stig Ramel; Wendy H. Raskind; Rodger C. Haggitt; Carissa A. Sanchez; Patrick J. Dean; Peter S. Rabinovitch; Brian J. Reid
The American Journal of Surgical Pathology | 1985
Patrick J. Dean; Rodger C. Haggitt; Carl J. O'hara
The American Journal of Surgical Pathology | 1994
Shari Taylor; Patrick J. Dean; Caroline A. Riely
American Journal of Clinical Pathology | 1987
Patrick J. Dean; Kenneth Groshart; James G. Porterfield; David H. Iansmith; Emmel Golden