Culture-dependent and culture-independent characterization of microorganisms associated with Aedes aegypti (Diptera: Culicidae) (L.) and dynamics of bacterial colonization in the midgut

In this work we show that the lumen of Aedes aegypti midgut is highly colonized by bacteria that were identified by culture-dependent and culture-independent methods. rDNA sequences obtained were compared with those from GenBank and the main bacterial genera identified were: Serratia, Klebsiella, Asaia, Bacillus, Enterococcus, Enterobacter,Kluyvera and Pantoea. All genera were identified in midgut except Enterobacter that was observed only in eggs. Asaia and Pantoea were also identified in eggs and ovary, respectively. In addition two yeast genera were observed in A. aegypti: Pichia isolated from midgut and Candida identified in midgut and ovary. The genus Serratia was dominant in all isolation assays representing 54.5% of the total of microorganisms. Thirty-nine and 24 bacterial clones were successfully obtained from midguts 24 and 48 h after blood feeding (ABF), respectively. The majority of clones obtained were from Serratia sp. (48.7% and 50% for 24 and 48 h ABF, respectively). Light microscopy showed that bacteria were located preferentially in the posterior midgut, around the blood meal and associated with peritrophic matrix. Scanning electron microscopy images showed a high number of bacteria in midgut during blood digestion and the peak of bacterial enumeration was reached 48 h ABF, stage in which lumen was almost totally occupied by bacteria that were also interacting with epithelial microvilli. Our results show the dynamics of microbial colonization and their distribution in midgut during blood digestion.     

Midgut volvulus in an adult with congenital malrotation

Congenital midgut malrotation, a rare anatomic anomaly that can lead to duodenal or small-bowel obstruction, rarely is observed beyond the first year of life. Symptomatic patients present with either acute bowel obstruction and intestinal ischemia with a midgut or cecal volvulus or with chronic vague abdominal pain. Chronic symptoms often can make the diagnosis difficult. By using several modalities such as barium studies, computerized tomography, angiography, and emergency laparotomy, we diagnosed midgut volvulus and partial intestinal obstruction, which occur rarely in an adult with congenital midgut malrotation.     

Persistent low urinary excretion of 5-HIAA is a marker for favourable survival during follow-up in patients with disseminated midgut carcinoid tumours

Survival of patients with disseminated midgut carcinoid tumours varies. We investigated which factors predict survival at referral and during follow-up, with emphasis on urinary 5-hydroxyindolacetic acid (5-HIAA) levels.Between 1992 and 2003, 76 patients were studied; urine was prospectively collected over a 24 h period every 3 months in order to measure 5-HIAA levels. Uni- and multivariate analyses were performed.Median follow-up was 55 months with a median survival of 54 months. Prognostic factors for poor survival were high age, high gamma-glutamyltransferase levels and greatly increased 5-HIAA levels (>20 mmol/mol creatinine) The Hazard Ratio (HR) of a greatly increased 5-HIAA level was 3.33 (95% confidence interval (CI) 1.66–6.66, p = 0.001).In a multivariate survival analysis with the 5-HIAA level as time dependent covariable, the HR for the 5-HIAA level was 1.007 (95% CI 1.004–1.010, p = 0.000).In conclusion, patients with persistent moderately increased urinary 5-HIAA levels ( 20 mmol/mol creatinine) have favourable outcome.     

Non-traumatic causes of perianal hemorrhage and excoriation in the young

The discovery at autopsy or at a death scene of fresh perianal hemorrhage and/or cutaneous excoriation in a young child is always of concern as this raises the possibility of inflicted injury. Three cases are reported where perianal bleeding and excoriation that were initially considered due to possible sexual assault were subsequently found to be of a non-suspicious nature. Case 1: A previously well 18-month-old boy was accidentally hanged. Fresh perianal hemorrhage that had raised the possibility of sexual assault was subsequently shown to be due to perineal streptococcal dermatitis. Case 2: A 2-year-old girl vomited and then stopped breathing. Fresh blood at the anus, that was also thought to be patulous, raised suspicions of sexual assault. At autopsy, however, bleeding around the normally configured anus was due to a midgut volvulus associated with intestinal malrotation. Case 3: A 21-month-old girl was found dead in her cot. Sexual abuse was suspected when lacerations were allegedly found around her anus. These were, however, due to skin lesions from her previously diagnosed ectodermal dysplasia clefting syndrome. Death was due to upper airway obstruction from acute and chronic inflammation. There was no evidence of anogenital trauma or sexual assault in any of the cases. Although inflicted traumatic causes of perianal hemorrhage and excoriation must be judiciously sought in the young, the current cases demonstrate that organic etiologies must also be considered. Perianal infections, congenital malformations of the mesentery and intestines, and inherited disorders of the skin may all produce findings that may initially suggest that sexual assault has occurred. Careful examination with appropriate photography and/or microbiological testing are required.     

Is ultrasonography a good screening test for intestinal malrotation?

Background

Early diagnosis of malrotation can prevent fatal midgut volvulus. Abnormal orientation of the superior mesenteric artery (SMA) and vein (SMV) on ultrasonography (US) has been described in malrotation. We aimed to determine the accuracy of this technique.

Methods

All children undergoing both upper gastrointestinal series (UGI) and US for possible malrotation over a 3-year period were reviewed. Patients were excluded if US did not include SMV/SMA orientation or if the duodenojejunal flexure was not visualized on UGI.

Results

Of 211 eligible patients, UGI and US were both normal in 62% and both abnormal in 15%. Forty-four had abnormal US and normal UGI (false positive, 21%), and 5 patients had normal US and abnormal UGI (false negative, 2%). Of these 5, none were found to have a short mesenteric base, which put them at risk for volvulus. Among abnormal ultrasounds, inversion of SMV/SMA and a “whirlpool” sign were more predictive for malrotation and volvulus than anterior/posterior orientation.

Conclusions

Ultrasonography is a good screening tool that effectively rules out malrotation at risk for volvulus. Children with an abnormal ultrasound should have an UGI or go to the operating room, depending on clinical findings.     

A Case of Fetal Midgut Volvulus and Jejunal Atresia: Nutritional Support and Maintenance of Mucosal Function and Integrity

Fetal midgut volvulus is a quite rare disease. Here, we report a case of a preterm newborn with fetal peritonitis, jejunal atresia with volvulus of post-atresic small bowel since about 30 cm from ileo-cecal valve (ICV) followed by a not-used microileus and microcolon. The surgical intervention consisted in the resection of volvulated necrotic small bowel followed by primary anastomosis. After surgery, total parenteral nutrition (TPN) has been started since 16^th of post-operative days when enteral feeding (EN) was administered with a lactose-free formula containing hydrolyzed protein and medium-chain triglycerides (Pregestimil). Re-establishing intestinal continuity was preferred rather than stoma that would have required TPN. In fact, re-operation could have led to a shorter residual small bowel (RSB), since the anastomosis was at 15 cm from ICV. Our study provides evidence that not only the type of procedure (enteral versus parenteral) of nutritional support, but also the type of milk may modify the outcome. Early EN should be encouraged in newborn abdominal surgical patients because it is associated with reduced complications.     

Midgut malrotation: radiological features of a twist of nature

To make an inventory of the radiological findings involved in midget malrotation 62 consecutive patients with surgically proven isolated malrotation of the midget were evaluated. Findings at plain abdominal radiography, upper gastrointestinal series. barium enema, ultrasound and/or CT were reviewed, correlated with the findings at surgery and classified into clinical entities related to embryological development. Findings were normal in 21 of 47 plain abdominal radiographs, 3 of 49 upper gastrointestinal series, 10 of 49 barium enemas and 9 of 14 ultrasound and/or CT examinations. All other examinations showed a multitude of abnormalities. Complete radiological classification into the clinical entities was possible in 39 patients (62.9 %). Partial classification could be established in the remaining 23 patients (37.1 %). It is concluded that midget malrotation is a treacherous disease with a multitude of appearance.By using the classification described, interpretation of findings becomes easier.     

Value of laparoscopy in children with a suspected rotation abnormality on imaging

Background

Although imaging is usually used for the diagnosis of rotation abnormalities, significant false-positive and false-negative rates have been reported. We studied the utility of laparoscopy in the management of children with a suspected rotation abnormality on imaging.

Methods

The charts of all children undergoing laparoscopy for a suspected intestinal rotation abnormality from January 2000 to August 2009 were retrospectively reviewed.

Results

There were 51 patients. Preoperative diagnosis based on upper gastrointestinal contrast study with or without contrast enema or ultrasound was malrotation without volvulus in 47%, malrotation with volvulus in 10%, and nonrotation in 6%; the other 37% had equivocal or inconclusive imaging studies. Of the patients who had a “definitive” preoperative diagnosis, 41% had a discrepant finding at laparoscopy. For those with inconclusive imaging studies, 32% were found on laparoscopy to have a narrow mesenteric base, which put them at significant risk of midgut volvulus.

Conclusion

Imaging studies may be inaccurate in differentiating malrotation from nonrotation or normal rotation. Laparoscopy provides an excellent opportunity to assess the base of the mesentery. Those children without a narrow-based mesentery can undergo laparoscopy alone, and those with malrotation should undergo either laparoscopic or open Ladd procedure.     

Malrotation: Current strategies navigating the radiologic diagnosis of a surgical emergency

The most accurate and practical imaging algorithm for the diagnosis of intestinal malrotation can be a complex and sometimes controversial topic. Since 1900, significant advances have been made in the radiographic assessment of infants and children suspected to have anomalies of intestinal rotation. We describe the current methods of abdominal imaging of malrotation along with their pros and cons. When associated with volvulus, malrotation is a true surgical emergency requiring rapid diagnosis and treatment. We emphasize the importance of close cooperation and communication between radiology and surgery to perform an effective and efficient diagnostic evaluation allowing prompt surgical decision making.