Packed with pills - obstructing duodenal web in the setting of intestinal malrotation: A case report.

BACKGROUND: The incidence of intestinal malrotation in adults has been reported to only be about 0.2%. Duodenal web as a cause of intestinal obstruction is rare, with an incidence of about 1:20000-1:40000. Furthermore, when described, these conditions are usually seen in early life and very infrequently in adulthood. CASE SUMMARY: We report a case of a middle-aged woman with intestinal malrotation who presented with a three-month history of right-sided abdominal pain, early satiety, and a 22-pound weight loss. Patient underwent an esophagogastroduodenoscopy, which demonstrated numerous retained pills in a deformed first portion of the duodenum, concerning for a partial gastric outlet obstruction. An upper gastrointestinal series showed marked distention of the proximal duodenum with retained debris and the presence of a windsock sign, increasing the suspicion of a duodenal web. The patient subsequently underwent surgical intervention where a duodenal web with two lumens was noted and resected, opening the duodenum. There were over 150 pill capsules that were removed. The patient is doing well after this intervention. CONCLUSION: Both intestinal malrotation and duodenal webs are infrequently encountered in the adult population. These pathologies can also present with nonspecific abdominal symptoms such as chronic abdominal pain and nausea. Hence, providers might not consider these pathologies in the differential for patients who present with vague symptoms which can lead to delay in management and increased mortality and morbidity.

A Peculiar Peritoneum: A Case of Tuberculosis in a Male Without Known Risk Factors.

Peritoneal tuberculosis is an uncommon diagnosis in developed countries and most commonly presents in patients with known risk factors for tuberculosis. We report a case of a patient without tuberculosis risk factors who presented with 4 years of intermittent fevers, several weeks of increasing abdominal distention, and newly discovered elevated liver tests. The diagnosis of peritoneal tuberculosis was confirmed following an extensive workup with a positive ascitic fluid culture for Mycobacterium tuberculosis. The patient's fevers resolved with antibiotic therapy, and antibiotic therapy was subsequently de-escalated based on the susceptibility profile.

α satellite DNA variation and function of the human centromere.

Genomic variation is a source of functional diversity that is typically studied in genic and non-coding regulatory regions. However, the extent of variation within noncoding portions of the human genome, particularly highly repetitive regions, and the functional consequences are not well understood. Satellite DNA, including α satellite DNA found at human centromeres, comprises up to 10% of the genome, but is difficult to study because its repetitive nature hinders contiguous sequence assemblies. We recently described variation within α satellite DNA that affects centromere function. On human chromosome 17 (HSA17), we showed that size and sequence polymorphisms within primary array D17Z1 are associated with chromosome aneuploidy and defective centromere architecture. However, HSA17 can counteract this instability by assembling the centromere at a second, "backup" array lacking variation. Here, we discuss our findings in a broader context of human centromere assembly, and highlight areas of future study to uncover links between genomic and epigenetic features of human centromeres.

Genomic variation within alpha satellite DNA influences centromere location on human chromosomes with metastable epialleles.

Alpha satellite is a tandemly organized type of repetitive DNA that comprises 5% of the genome and is found at all human centromeres. A defined number of 171-bp monomers are organized into chromosome-specific higher-order repeats (HORs) that are reiterated thousands of times. At least half of all human chromosomes have two or more distinct HOR alpha satellite arrays within their centromere regions. We previously showed that the two alpha satellite arrays of Homo sapiens Chromosome 17 (HSA17), D17Z1 and D17Z1-B, behave as centromeric epialleles, that is, the centromere, defined by chromatin containing the centromeric histone variant CENPA and recruitment of other centromere proteins, can form at either D17Z1 or D17Z1-B. Some individuals in the human population are functional heterozygotes in that D17Z1 is the active centromere on one homolog and D17Z1-B is active on the other. In this study, we aimed to understand the molecular basis for how centromere location is determined on HSA17. Specifically, we focused on D17Z1 genomic variation as a driver of epiallele formation. We found that D17Z1 arrays that are predominantly composed of HOR size and sequence variants were functionally less competent. They either recruited decreased amounts of the centromere-specific histone variant CENPA and the HSA17 was mitotically unstable, or alternatively, the centromere was assembled at D17Z1-B and the HSA17 was stable. Our study demonstrates that genomic variation within highly repetitive, noncoding DNA of human centromere regions has a pronounced impact on genome stability and basic chromosomal function.