The hairy polyp: a benign teratoma of the colon

A 76-year-old female presented with bright red rectal bleeding. Endoscopic evaluation revealed a polypoid lesion sprouting hair in the sigmoid colon. Histologically the resected polyp was composed of elements of all three germ layers, fulfilling the criteria for a teratoma. The differential diagnosis of this benign polyp and its significance are discussed.     

Does hormonal therapy have any benefit for bleeding angiodysplasia?

Sixty-four patients took part in a cohort study measuring the efficacy of daily hormonal therapy in diminishing intestinal bleeding from small bowel angiodysplasia. Thirty patients received 5-10 mg norethynodrel either with mestranol, 0.075-0.15 mg (24 patients) or with conjugated estrogens, 0.625 mg (six patients). The cohort group consisted of 34 patients who either refused hormonal therapy (six patients) or were diagnosed early in our experience, before the resurgence of hormonal therapy (28 patients). Mean follow-up was 15.6 months (range 2-31 months) for the treated group and 13.4 months (range 1-23 months) for the untreated group. In addition, the change in monthly transfusion requirement with therapy was analyzed ("within group" analysis). Fifty percent (15 of 30) of the treated group required no further transfusion during therapy, while 44% (15 of 34) of the untreated group required no further therapy (not significant). During therapy, the mean monthly transfusion requirement of packed red blood cells in the treated group was not significantly different from that found before therapy (1.5 vs. 2.2 units, NS) or from that of the control group (1.5 vs. 1.6 units, NS). The findings do not support the use of hormonal therapy for bleeding from small intestinal angiodysplasia.     

DHCR7 genotypes of cousins with Smith-Lemli-Opitz syndrome

Smith-Lemli-Opitz syndrome (SLOS) is an autosomal recessive disorder of cholesterol biosynthesis caused by mutations of the 7-dehydrocholesterol reductase gene (DHCR7). We report on three cousins with SLOS, all of whom were found to be compound heterozygotes for the common splice site mutation IVS8-1G-->C and the missense mutation T289I. DNA analysis of one set of parents demonstrated that the father carried the missense mutation and the mother carried the IVS8-1G-->C mutation. By extension, the two unrelated mothers were both heterozygous for IVS8-1G-->C. This finding supports the notion of a high carrier frequency of the IVS8-1G-->C null mutation in Northern European Caucasians.     

Colonoscopy 'my way': preparation, anticoagulants, antibiotics and sedation.

Colonoscopy was introduced in the 1960s. The facility with which this technique is performed has been enhanced by vast improvements in instrumentation. In spite of this, physician attitudes concerning colonoscopy have changed little over the past several decades. The diet for precolonoscopic preparation has not been altered for 30 years. Colonoscopists have a great reluctance to use a new preparation instead of the 4 L electrolyte solution, perhaps because this was such a significant advance in colonoscopic cleansing, its predecessor being castor oil and enemas. Physicians continue to be wary of the patient who is taking acetylsalicylic acid in the absence of any studies that show that this is detrimental for polypectomy. The management of the patient on warfarin anticoagulation remains a subject for debate. As for antibiotic prophylaxis, most endoscopy units do not have a standardized approach, although there are good guidelines that, if followed, should decrease the risk of infective endocarditis. Sedation for the endoscopic examination is usually administered by the colonoscopist, although anesthesiologists may, in some countries (and in some defined areas of the United States) be the primary administrators of sedation and analgesia. The present article is a personal approach to the following issues: the preparation of the colon for an examination, current thoughts about anticoagulation and acetylsalicylic acid, antibiotic prophylaxis for colonoscopy and the technique for sedation out of the hospital.     

Fluoridation cessation and oral health equity: a 7-year post-cessation study of Grade 2 schoolchildren in Alberta,Canada

ObjectiveCommunity water fluoridation, because of its universal scope and passive mechanism of uptake, is one component of a multifaceted approach to promoting equity in dental health. The objective of this study was to examine social inequities in children’s dental health in the Canadian cities of Calgary (fluoridation cessation in 2011) and Edmonton (still fluoridated).MethodsWe analyzed data from surveys of population-based samples of Grade 2 (approx. age 7) children in Calgary in 2009/2010 (pre-cessation; n=557) and in both Calgary and Edmonton in 2013/2014 (Calgary, n=3230; Edmonton, n=2304) and 2018/2019 (Calgary, n=2649; Edmonton, n=2600) (post-cessation). We estimated associations between several socioeconomic indicators and dental caries indicators (i.e., dental caries experience [deft, DMFT] and untreated decay in two or more teeth [untreated decay]) using zero-inflated Poisson, binary logistic regression, and the concentration index of inequality. We compared those associations over time (between survey waves) and between cities at post-cessation.ResultsPersistent social inequities in deft and untreated decay were evident; for example, having no dental insurance was significantly associated with higher odds of untreated decay across city and survey wave. In most (but not all) cases, differences between cities and survey waves were consistent with an adverse effect of fluoridation cessation on dental health inequities. For example, the association between no dental insurance and higher odds of untreated decay in Calgary was greater in 2018/2019 (later post-cessation) than in 2009/2010 (pre-cessation; odds ratio [OR] for comparison of coefficients = 1.89 [1.36–2.63], p<0.001) and 2013/2014 (early post-cessation; OR for comparison of coefficients = 1.67 [1.22–2.28], p=0.001); that same association in 2018/2019 was greater in Calgary (fluoridation cessation) than in Edmonton (still fluoridated) (OR for comparison of coefficients = 1.44 [1.03–2.02], p=0.033).ConclusionSocial inequities in dental caries were present in both Calgary and Edmonton. Those inequities tended to be worse in Calgary where fluoridation was ceased. Our findings may be relevant to other settings where income inequality is high, dental services are costly, and dental public health infrastructure is limited.     

Wide view and retroview during colonoscopy

Colonoscopy is the best imaging device currently available for the detection of lesions in the large bowel, but may be an imperfect tool against colon cancer. Because recent guidelines for colorectal cancer screening and surveillance depend on whether polyps are found on colonoscopy and on their size, the need to identify all the neoplasia in the colon has assumed greater importance. This article reviews and assesses the latest developments in colonoscopy including wide-angle optics, endoscope caps and hoods, retroflexion and the use of the third eye retroscope.     

Colonoscopy and endoscopic therapy for delayed post-polypectomy hemorrhage.

Nine consecutive patients in whom endoscopic management of delayed post-polypectomy hemorrhage was attempted are described. Each patient presented with active rectal bleeding 12 hours to 12 days after snare resection of a colon polyp. In each patient, repeat colonoscopy identified the bleeding site and various combinations of injection therapy, electrocautery, or thermal injury led to cessation of hemorrhage. No complications resulted from repeat colonoscopy and endoscopic therapy. Colonoscopy and endoscopic therapy is feasible, effective, and safe in selected patients with active delayed post-polypectomy hemorrhage.     

The prenatal identification of fetal compatibility in neonatal alloimmune thrombocytopenia using amniotic fluid and variable number of tandem repeat (VNTR) analysis

Summary. Most severe episodes of neonatal alloimmune thrombocytopenic purpura (NATP) are caused by antiplatelet alloantibodies against the HPA-la (Pl^A1) antigen. However, half of subsequent fetuses produced from a HPA-la/b father (genotypic frequency 28%) will result in a child who is not affected. Some investigators manage NATP by confirming the fetal platelet phenotype using percutaneous umbilical cord sampling, a procedure that carries a low but real risk of fetal morbidity and mortality. More recently, physicians determine the fetal platelet antigen genotype using DNA derived from amniotic fluid or chorionic villus samples. All therapy is withdrawn for a fetus who genotypes as HPA-lb/b. However, since the fetus is the same genotype as the mother, there can be uncertainty about the origin of the genetic material and thus the validity of the fetal genotype. The inappropriate withdrawal of therapy for a erroneously genotyped fetus could be fatal, and consequently many physicians advocate fetal HPA-1 phenotyping with confirmation using percutaneous umbilical blood sampling. In this report we describe the management of two pregnancies with previously affected infants due to anti-HP A-la alloantibodies. Both husbands were HPA-la/b. For the current pregnancies, amniotic fluid was collected at 20 or 29 weeks of gestation, and the platelet genotype indicated that the fetuses were HPA-lb/b. The fetal origin of the amniotic fluid derived DNA was confirmed by the forensic technique of DNA profiling using variable number of tandem repeat (VNTR) analysis. All therapy was withdrawn, percutaneous umbilical blood sampling was not performed, and both women vaginally delivered healthy non-thrombocytopenic infants. The application of platelet alloantigen genotyping using DNA from amniotic fluid cells identified the HPA-lb/b fetus, and VNTR analysis confirmed that the tissue was fetal derived, thus avoiding the necessity for percutaneous umbilical blood sampling. The use of this approach in patients at risk will avoid additional investigation and treatment in approximately one-seventh of all NATP pregnancies involving the HPA-la antigen.     

Human beta satellite DNA: genomic organization and sequence definition of a class of highly repetitive tandem DNA

We describe a class of human repetitive DNA, called beta satellite, that, at a most fundamental level, exists as tandem arrays of diverged approximately equal to 68-base-pair monomer repeat units. The monomer units are organized as distinct subsets, each characterized by a multimeric higher-order repeat unit that is tandemly reiterated and represents a recent unit of amplification. We have cloned, characterized, and determined the sequence of two beta satellite higher-order repeat units: one located on chromosome 9, the other on the acrocentric chromosomes (13, 14, 15, 21, and 22) and perhaps other sites in the genome. Analysis by pulsed-field gel electrophoresis reveals that these tandem arrays are localized in large domains (50-300 kilobase pairs) that are marked by restriction fragment length polymorphisms. In total, beta satellite sequences comprise several million base pairs of DNA in the human genome. Analysis of this DNA family should permit insights into the nature of chromosome-specific and nonspecific modes of satellite DNA evolution and provide useful tools for probing the molecular organization and concerted evolution of the acrocentric chromosomes.     

Examining the clinical use of hemochromatosis genetic testing

BACKGROUND:Hereditary hemochromatosis leads to an increased lifetime risk for end-organ damage due to excess iron deposition. Guidelines recommend that genetic testing be performed in patients with clinical suspicion of iron overload accompanied by elevated serum ferritin and transferrin saturation levels.OBJECTIVE:To evaluate guideline adherence and the clinical and economic impact of HFE genetic testing.METHODS:The electronic charts of patients submitted for HFE testing in 2012 were reviewed for genetic testing results, biochemical markers of iron overload and clinical history of phlebotomy.RESULTS:A total of 664 samples were sent for testing, with clinical, biochemical and phlebotomy data available for 160 patients. A positive C282Y homozygote or C282Y/H63D compound heterozygote test result was observed in 18% of patients. Patients with an at-risk HFE genotype had significantly higher iron saturation, serum iron and hemoglobin (P<0.001), without higher ferritin or liver enzyme levels. Fifty percent of patients referred for testing did not have biochemical evidence of iron overload (transferrin saturation >45% and ferritin level >300 μg/L). Patients were four times more likely to undergo phlebotomy if they were gene test positive (RR 4.29 [95% CI 2.35 to 7.83]; P<0.00001).DISCUSSION:One-half of patients referred for testing did not exhibit biochemical evidence of iron overload. Many patients with biochemical evidence of iron overload, but with negative genetic test results, did not undergo phlebotomy. A requisition to determine clinical indication for testing may reduce the use of the HFE genetic test. Finally, improvement of current genetic test characteristics would improve rationale for the test.CONCLUSION:A significant proportion of hemochromatosis genetic testing does not adhere to current guidelines and would not alter patient management.