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Luis Uscanga

Publications and source records attributed to Luis Uscanga.

12 recordsLinked to original sources
PubMed2006

Perinuclear anti-neutrophil cytoplasmic antibodies (p-anca) in chronic ulcerative colitis: experience in a Mexican institution.

AIM: To assess the prevalence and clinical value of p-ANCA in a sample of Mexican ulcerative colitis (UC) patients. METHODS: In a prospective, IRB-approved protocol, p-ANCA was determined in 80 patients with UC (mean age, 32 +/- 12.9 years). The severity and extension of disease were determined by clinical methods, searching a statistical association with p-ANCA status. RESULTS: p-ANCA were detected in 41 (51%) patients. Severity of disease was the only clinical variable statistically associated with their presence (P < 0.0001; OR = 9; CI 95% = 3.2-24.7). CONCLUSION: The prevalence of p-ANCA was similar to that reported in other countries. Their presence was associated to UC severity, but offered no more information than the obtained by clinical methods.

Adult↗
PubMed2006

Clinical characteristics of a group of adults with nodular lymphoid hyperplasia: a single center experience.

AIM: To describe the clinical and histological characteristics of a group of adults with small-bowel nodular lymphoid hyperplasia (NLH). METHODS: Patients were searched for five years in pathology records of our institution. The biopsy material was reassessed using strict histopathological criteria. Clinical data were obtained from medical records. RESULTS: Small-bowel NLH was diagnosed in 18 cases. The female: male ratio was 2:1. The most frequent symptoms were diarrhea (72%), involuntary weight loss (72%) and abdominal pain (61%). Nine patients (50%) had immunodeficiency. Small-bowel bacterial overgrowth was found in three (17%) cases. At small-bowel NLH diagnosis, three (17%) had associated lymphoma: two intestinal and one extra-intestinal lymphomas. In two patients with villous atrophy and anti-endomysial antibodies the diagnosis of celiac disease was established. Giardia lamblia infection was found in only one patient with hypogammaglobulinemia (Herman's syndrome). CONCLUSIONS: NLH is uncommon in adult patients. Associated diseases are immunodeficiency and lymphoid tissue malignancies.

Adolescent↗
PubMedDate not supplied

Effect of ulcerative colitis in the bursting strength of colonic anastomoses in rats.

Inflammatory bowel disease may have a deleterious effect on bowel healing, but its role is difficult to demonstrate in clinical practice because of the association of multiple factors. An experiment was conducted in rats. They were divided into two groups: group I, a model of acetic acid induced colitis, and group II, the control group. Both groups underwent a rectal resection and primary anastomosis. On postoperative day 7, the bursting strength of the anastomosis was evaluated. There were 44 rats in group I and 38 in group II. In 91% of group I rats there were histopathological changes compatible with inflammatory bowel disease (IBD). Mean bursting pressure was significantly reduced in rats with acetic-acid induced IBD (142.18 +/- 18.22 mm Hg in group I, and 208.85 +/- 14.8 mm Hg in group II; p < .05). These results suggest the deleterious effect of IBD on bowel healing.

Acetic Acid↗
PubMedDate not supplied

[Surgical treatment of lower digestive tract hemorrhage. Experience at the Instituto Nacional de Ciencias Médicas y Nutrición Salvador Zubirán].

BACKGROUND: Lower gastrointestinal bleeding is usually self-limiting in about 80% of cases; however, surgical treatment may be required in selected cases. Preoperative precise identification of the bleeding source is crucial for a successful outcome. OBJECTIVE: To determine the most frequent diagnoses, as well as short and long-term results in a series of patients who underwent a surgical procedure for lower gastrointestinal bleeding. MATERIAL AND METHODS: Retrospective analysis of 39 patients operated upon for lower gastrointestinal bleeding from 1979 through 1997 in a referral center. Demographic data, history, physical examination, laboratory tests, resuscitative measures, preoperative work-up for identification of bleeding source, definitive cause of bleeding, surgical procedure, operative morbidity and mortality, as well as long-term status and recurrence of bleeding were recorded. RESULTS: There were 54% women and 46% men. Mean age was 56 years (range, 15-92). Most patients presented hematochezia (69%). Colonoscopy was the most used diagnostic procedure (69%). The bleeding source was located in 90% of patients. Diverticular disease was the most frequent cause of bleeding. A segmental bowel resection was the treatment in 97% of cases. Morbidity was 23% with 18% of mortality. Recurrence occurred in 9% of survivors. CONCLUSIONS: Morbidity and mortality were high. Patients who require a surgical operation should be carefully selected and evaluated with a complete work-up to determine the site and cause of bleeding.

Academies and Institutes↗
PubMedDate not supplied

[Endoscopic cholangiography in mild acute biliary pancreatitis: when and for whom?].

BACKGROUND: Endoscopic retrograde cholangiopancreatography (ERCP), with or without sphincterotomy, has been widely used in patients with severe biliary acute pancreatitis (BAP) or those with cholangitis and/or obstruction of the biliary tree. Its use in subjects with mild BAP is more controversial. AIM: To optimize use of ERCP in patients with mild pancreatitis due to gallstones by identifying clinical and biochemical predictors of choledocholithiasis. MATERIAL AND METHOD: The clinical and biochemical data, images, and outcomes of 83 patients with mild BAP hospitalized at the Instituto Nacional de Ciencias Medicas y Nutricion "Salvador Zubiran" from January 1, 1988 to May 30, 2000 were retrospectively analyzed. All patients received elective cholecystectomy at hospital admission. In 35 cases, ERCP was performed before cholecystectomy (group A). The remaining 48 were operated on without ERCP (group B). In 30, transcystic-cholangiography was done. Forty-seven (57%) were female. Mean age was 47 years (19-90). Mean time between onset of AP and hospital admission was 2.2 days (1-15), and between clinical onset and cholecystectomy, eight days (1-26). Statistical differences were evaluated by non-parametric methods. An univariated and multivariated analysis was performed looking for data to identify choledocholithiasis. RESULTS: Choledocholithiasis was found in 27 cases (32%), 18 from group A (51%), and nine for group B (19%) (RR = 4.58, IC 95% = 1.7-12.25, p = 0.004). ERCP was performed in all cases because of clinical suspicion of choledocholithiasis (jaundice, bilirubin, and alkaline phosphatase alteration and/or choledochal dilation); however, none of the patients of group B in whom choledocholithiasis was operatively diagnosed showed biochemical or radiologic alterations. Subjects with choledocolithiasis presented more frequently a history of biliary pain (RR = 5.75, IC 95% = 1.76-18.7), jaundice (RR = 3.07, IC 95% = 1.15-8.16) and/or alkaline phosphatase elevation (RR = 4.11, IC 95% = 1.3-12.7). CONCLUSION: The high frequency of choledocholithiasis in subjects with mild biliary pancreatitis warranted radiologic exploration of the biliary tree in all patients submitted to cholecystectomy. In those with jaundice, alkaline phosphatase elevation and/or a history of biliary pain, ERCP should be performed prior to the operation; in others, choledocholithiasis can be discharged by operative transcystic cholangiography. Therapeutic measures for treating choledocholithiasis should be adapted to hospital facilities.

Acute Disease↗
PubMedDate not supplied

[Predictors of colectomy in patients with ulcerative colitis. A cohort analysis of 184 cases].

BACKGROUND: At the present time procto-colectomy is the only potentially curative therapeutic measure for patients with ulcerative colitis (UC). Due to its morbidity and mortality, several prognostic indexes have been proposed to identify subjects in whom surgery could be beneficial. However, they have limited availability or they are very cumbersome for the individual patient. AIM: To analyze demographic, clinical and biochemical variables in a group of 184 Mexican patients with UC in order to identify predicting factors for procto-colectomy. PATIENTS AND METHODS: Subjects were divided into two groups: A. Those in whom a procto-colectomy was performed (n = 52) and B. Patients on medical treatment in = 132). Continuous variables were analyzed by means of the Student's t test and categorical variables by means of chi-square statistic. A multivariate analysis was performed using logistic regression. RESULTS: The main indication for surgery was failure to medical treatment (78%). Procto-colectomy was elective in 28 cases and an emergency procedure in 14 (7 failures to medical treatment, 4 colonic perforations, 2 toxic megacolons and 1 uncontrolled hemorrhage). All operated subjects had pancolitis and showed more bloody bowel movements per day (> 10), fever (> 38.5 degrees C), tachycardia, hipoalbuminemia and hospitalizations. Only hypoalbuminemia in subjects with universal colitis was consistently associated to procto-colectomy. CONCLUSION: Pancolitis, hypoalbuminemia and previous hospitalizations were the strongest predictors of procto-colectomy in our cohort. Thus, serum protein determinations can be useful in patients with universal UC to decide surgical therapy.

Adult↗
PubMedDate not supplied

Gastrointestinal stromal tumors: clinical and pathological analysis of 24 cases.

BACKGROUND: Gastrointestinal stromal tumors (GISTs) are mesenchymal neoplasms of the gastrointestinal tract. They are positive for the expression of c-Kit protein at immunohistochemistry and their clinical presentation is variable. We conducted a study to identify true GISTs with known pathological and immunohistochemical criteria from other tumors of the gastrointestinal tract. METHODS: The clinical records of patients with the diagnosis of schwannoma, leiomyoma, leiomyosarcoma and tumor of uncertain biological behavior of the gastrointestinal tract were identified and the slides of paraffin obtained for review by two experienced pathologists in the diagnosis of GISTs. The clinical presentation, treatment and outcomes were analyzed. RESULTS: Twenty four GISTs (11 low-risk and 13 high-risk) were identified from 76 cases reviewed. All the confirmed GISTs were positive at immunohistochemistry for c-Kit expression. The two predominant location of the tumors were the stomach and small intestine. The outcome was good for benign and completely resected tumors. CONCLUSIONS: True GISTs can be recognized from other tumors by histological analysis. Immunohistochemistry to identify c-Kit protein expression is useful to confirm the diagnosis. Physicians must consider GISTs in patients with a lesion of the gastrointestinal tract resembling a smooth muscle tumor or/and in association with chronic or acute bleeding.

Adult↗
PubMedDate not supplied

[Peutz-Jeghers syndrome].

OBJECTIVE: To describe the demographic, clinical characteristics and associated diseases in eight patients with the Peutz-Jeghers syndrome seen at the INCMNSZ and literature review. SETTING: National Institute of Health. DESIGN: Description of eight cases of Peutz-Jeghers syndrome and literature review. MATERIAL AND METHODS: A retrospective review of all the discharge diagnosis was doing between January 1987 to February 2004. The diagnosis of Peutz-Jeghers syndrome was made on clinical and anatomical grounds. The clinical features, follow-up, treatment and last visit clinical status were analyzed in all the patients. PRESENTATION OF CASES: Eight patients with the Peutz-Jeghers syndrome were investigated, five women and three men. The median of time at diagnosis was 31 years-old (range, 26-37). All the patients had mucocutaneous pigmentation and hamartomatous polyps. The ileum and large bowel were the most frequent sites of the polyps, and there were generally sessile and pedunculated. The major abdominal symptoms were abdominal pain, GI bleeding, intestinal obstruction, weight loss and intussusception. One case of small-bowel cancer and one of serous cystadenoma of the ovary were detected. Surgical interventions were doing in five patients; the most frequent indication was polyp-induced bowel obstruction. All the patients are alive to date.

Adult↗
PubMedDate not supplied

[Pancreatoduodenectomy: results in a large volume center].

OBJECTIVE: Analyze the experience with pancreaticoduodenectomy (PD) at the INCMNSZ. BACKGROUND DATA: PD has become a popular procedure in hospitals throughout the USA and Europe in the last 25 years, where mortality is < 5% y morbidity remains around 40%. Nonetheless there are very few reports on PD in Latin America. METHODS: The data of all PD's performed at the INCMNSZ between 1999 and 2005 was gathered prospectively and analyzed retrospectively. RESULTS: 133 PDs where performed; 47.5% where men and 52.5% where women. Median of age was 57.7 years. 81.5% underwent classical resection and 18.5% a pylorus preserving procedure. Intraoperative variables include: blood loss: 940 mL. (1,000). transfusion requirements: 1.9 U, median operative time: 5:49 (+/- 1:02) and median hospital stay: 14 days. Most frequent diagnosis include ampulary adenocarcinoma and pancreatic cancer Mortality in the entire series was 9.2%, decreased to 2.7% in the 2002-2005 period and from April 2003 has remained in 0. A total of 14 portal-superior mesenteric vein resections where performed. CONCLUSIONS: To our knowledge this is the largest series of PD in Latin America. Popularity and indications for PD are expanding. Mortality is acceptable and morbidity remains high despite much effort. This procedure is performed with a satisfactory outcome in high volume centers. Involvement of the portal-superior mesenteric vein is not a contraindication of PD.

Adenocarcinoma↗