Bowel and mesenteric injury following blunt abdominal trauma: evaluation with CT

Computed tomography (CT) used in cases of blunt abdominal trauma has been found sensitive in detection of bowel and mesenteric injuries and discrimination of operable from nonoperable candidates. In 51 patients with suspected bowel or mesenteric injury following blunt abdominal trauma, CT correctly depicted bowel hematoma or mesenteric injury in 17 of 19 nonoperable patients (89%) and severe injuries in one patient who died preoperatively. In 26 of 28 patients who underwent therapeutic laparotomy (93%), initial CT enabled identification of surgically confirmed injuries. In two cases, initial scan misinterpretation delayed diagnosis of serious bowel injuries. The correct interpretation was rendered preoperatively and at blind retrospective review. CT findings that correlated with bowel or mesenteric injury requiring surgery were free peritoneal fluid (27 of 28, 96%), mesenteric infiltration (24 of 28, 86%), thick-walled bowel (17 of 28, 61%), associated abdominal injuries (12 of 28, 43%), and free air (nine of 28, 32%). In nonoperable cases, CT scans demonstrated bowel thickening (84%) but less frequently peritoneal fluid (21%), mesenteric infiltration (26%), or associated injuries (5%). In three of four patients who underwent nontherapeutic laparotomy, preoperative CT correctly imaged the limited abdominal injuries.     

The rare alpha-thalassemia-1 of blacks is a zeta alpha-thalassemia-1 associated with deletion of all alpha- and zeta-globin genes

Restriction endonuclease mapping with alpha and zeta-globin gene probes showed differences between the alpha-thalassemia-1 (alpha-thal-1) condition in two patients with HbH disease. One patient had the rare black type of alpha-thal-1 together with alpha-thal-2 and HbS heterozygosities. The second patient was a Laotian child with HbE, Hb Constant Spring (alpha-thal-2), and alpha-thal-1 heterozygosities. The diagnoses were based on clinical, hematologic, and biochemical data. Whereas DNA fragments hybridizing to a zeta-probe were obtained from the Laotian type of alpha-thal-1, neither alpha nor zeta-gene fragments could be identified deriving from the black type of alpha-thal-1. Therefore, the black type of alpha-thal-1 is associated with a deletion of the entire zeta 2-psi zeta-psi alpha-alpha 2-alpha 1 gene complex and can be considered a zeta alpha-thal-1. It is likely that homozygosity for such a condition will lead to embryonic wastage, explaining the absence of hydrops fetalis in blacks.     

A prospective study of wound infection in coronary artery surgery.

OBJECTIVE: The incidence of wound infection in coronary artery surgery is low, but there is an appreciable mortality associated with sternal infection. In other fields of surgery there is evidence that an all disposable paper gown and drape system has protective advantages over a fabric system. Using an established wound scoring system (ASEPSIS), we investigated this in a prospective, randomised trial of patients undergoing cardiac surgery. METHODS: 505 patients undergoing isolated coronary artery surgery in a single hospital over an 18 month period were randomised to either a disposable, paper drape system or re-usable fabric drapes. Allocation was stratified according to whether or not the patient had had previous coronary artery surgery. Patients were followed for 3 months. Total infection scores for each wound were calculated from daily scores collected in hospital together with the scores at six weeks and three months. RESULTS: The two randomised groups were otherwise well matched. Full follow-up information was available for 464 (92%) patients. There was no evidence of any difference in rates of sternal or leg wound infection between the two groups (P = 0.87 and 0.62, respectively). Women were more likely to have infected sternal wounds (P = 0.17) and significantly more likely to have infected leg wounds (P = 0.04). Patients with sternal wound infections had a significantly higher body mass index (P = 0.001). High Parsonnet scores and increased time on ventilation were significantly associated with leg wound but not sternal infections. For both wound sites, patients with infections had spent longer in the operating theatre. CONCLUSION: In a randomised controlled study of patients undergoing coronary artery surgery we found that the use of paper drapes and gowns conferred no benefit over a reusable fabric in terms of post-operative wound infection. Although females and diabetics are more likely to experience this complication, an important additional risk factor is an extended operating time.     

Dental stem cells and their potential role in apexogenesis and apexification

Injury to an immature permanent tooth may result in cessation of dentine deposition and root maturation leaving an open root apex and thin dentinal walls that are prone to fracture. Endodontic treatment is often complicated and protracted with an uncertain prognosis frequently resulting in premature tooth loss. Postnatal stem cells, which are capable of self‐renewal, proliferation and differentiation into multiple specialized cell lineages have been isolated and identified within the dental pulp, apical papilla and periodontal ligament. The ability of these cells to produce pulp‐dentine and cementum‐periodontal ligament complexes in vivo suggest potential applications involving stem cells, growth factors and scaffolds for apexification or apexogenesis. Similar protein expression amongst dental stem cells possibly implicates a common origin; however, the dominant cells to repopulate an open apex will be directed by local environmental cues. A greater understanding of the structure and function of cells within their environment is necessary to regulate and facilitate cellular differentiation along a certain developmental path with subsequent tissue regeneration. This review focuses on development of the apical tissues, dental stem cells and their possible involvement clinically in closing the open root apex. MEDLINE and EMBASE computer databases were searched up to January 2009. Abstracts of all potentially relevant articles were scanned and their contents identified before retrieval of full articles. A manual search of article reference lists as well as a forward search on selected authors of these articles was undertaken. It appears that dental stem cells have the potential for continued cell division and regeneration to replace dental tissues lost through trauma or disease. Clinical applications using these cells for apexogenesis and apexification will be dependent on a greater understanding of the environment at the immature root end and what stimulates dental stem cells to begin dividing and then express a certain phenotype.     

Pancreatic abscess: predictive value of early abdominal CT

The value of a recently reported grading system of early abdominal computed tomography (CT) for predicting development of pancreatic abscess in patients with acute pancreatitis was reassessed. When the previously described CT grading system was used in another patient population, it did not demonstrate the same degree of prognostic value of baseline CT. In this series pancreatic abscess occurred in only eight of 29 patients (28%) with grade E CT scans (with grade E representing the most severe involvement), compared with 60% in the previous series. Of 44 patients with either grade D or E baseline CT scans, abscesses developed in only 30%, with a minimum clinical follow-up of 3 months. A second grading system, which used a semiquantitative analysis of the degree of peripancreatic inflammation (a "CT severity score"), also did not strongly correlate with the future risk of abscess, The authors conclude that early abdominal CT should be performed selectively in patients with acute pancreatitis and reserved for patients who are either diagnostic dilemmas or who fail to respond to supportive treatment and have clinically suspected surgical complications such as pancreatic abscess.     

AIDS-related cholangitis: radiographic findings in nine patients

Acalculous inflammation of the biliary tract is a recently reported complication of the acquired immunodeficiency syndrome (AIDS). In a 33-month period, nine men with AIDS were evaluated because of right upper quadrant and/or epigastric pain, jaundice, or abnormal liver function test results. Each patient underwent ultrasonography and endoscopic retrograde cholangiopancreatography; seven also underwent computed tomography. In eight of nine patients the imaging studies disclosed intrahepatic and extrahepatic bile duct changes identical to those seen in sclerosing cholangitis (strictures, focal dilatation, thickened duct walls). Isolated papillary stenosis and ductal dilatation were present in one patient, while eight patients had some stricturing of the distal common duct. The combination of papillary stenosis and intrahepatic ductal strictures appears unique to AIDS-related cholangitis. Endoscopic papillotomy provided variable relief to symptoms and biochemical abnormalities. Cholangitis caused by cytomegalovirus and/or Cryptosporidium infection is the proposed pathophysiologic mechanism.