Atypical 22q11.2 deletion in a patient with DGS/VCFS spectrum

Deletions in region 22q11.2 usually occur between two low copy repeat regions (LCRs), which are preferred chromosome sites for rearrangements. Most of the deletions encompass the same 3 or 1.5 Mb region, with breakpoints at LCR A and D or at LCR A and B, respectively. We report on a patient with clinical features of the 22q deletion syndrome who presents a novel, atypical deletion, smaller than 1.5 Mb, with distal breakpoint in LCR B and proximal breakpoint within no known LCR site.     

New fimbrial gene cluster of S-fimbrial adhesin family

Fimbrial adhesins that mediate attachment to host cells are produced by most virulent Escherichia coli isolates. These virulence factors play an important role in the initial stages of bacterial colonization and also in determination of the host and tissue specificity. Isolates belonging to serotype O78 are known to cause a large variety of clinical syndromes in farm animals and humans and have been shown to produce several types of adherence fimbriae. We studied the fimbrial adhesin from an avian septicemic E. coli isolate of serotype O78. Analysis of the genetic organization of the fac (fimbria of avian E. coli) gene cluster indicates that it belongs to the S-fimbrial adhesin family. Seven open reading frames coding for major and minor structural subunits were identified, and most of them showed a high degree of homology to the corresponding Sfa and Foc determinants. The least-conserved open reading frame was facS, encoding a protein known to play an important role in determining adherence specificity in other S-fimbrial gene clusters.     

No benefit from combining HE4 and CA125 as ovarian tumor markers in a clinical setting

Objective

About 70% of epithelial ovarian cancer patients (EOC) are diagnosed at advanced stage with a five-year survival rate of only 30%. Whilst CA125 detects peritoneally-spread disease, it has limited sensitivity for early cancers, many of which are potentially curable.

Methods

We compared the new commercially available tumor marker HE4 with CA125 individually, in combination, within the risk of malignancy index (RMI) and the newly defined risk of malignancy algorithm (ROMA). Our prospectively-collected cohort of 160 patients consisted of healthy controls, benign diseases, and borderline tumors/adenocarcinomas of ovarian, tubal, peritoneal and endometrial origin. HE4 and CA125 were measured in serum using standardized ELISA.

Results

Both markers showed similar diagnostic performance in the detection of EOC at clinically defined thresholds (CA125 35 U/ml; HE4 70 pM) but HE4 was not elevated in endometriosis. Comparison of non-malignant diagnoses (n = 71) versus early stage ovarian and tubal cancers (n = 19) revealed that HE4 and ROMA displayed the best diagnostic performance (AUC 0.86/0.87, specificity 85.9%/87.3% and sensitivity 78.9%/78.9%, respectively). Whilst RMICA125 detects peritoneal cancer better than all other models (AUC 0.99, specificity 97.2%, sensitivity 80.0%), there is no other detection benefit from RMI compared to HE4 alone or included in ROMA.

Conclusions

The major advantage of HE4 lies in its specificity and improved detection of borderline tumors and early stage ovarian and tubal cancers. HE4 is superior to CA125 with or without RMI and ROMA indices. However, we see no benefit from combining both markers in clinical practice.     

Molecular Basis of Commensalism in the Urinary Tract: Low Virulence or Virulence Attenuation?

In some patients, Escherichia coli strains establish significant bacteriuria without causing symptoms of urinary tract infection (UTI). These asymptomatic-bacteriuria (ABU) strains have been shown to express fewer virulence factors than the uropathogenic E. coli (UPEC) strains that cause severe, symptomatic UTI. Paradoxically, ABU strains carry many typical UPEC virulence genes, and the molecular basis of their low virulence therefore remains unclear. This study examined whether ABU strains might evolve from UPEC by genome loss and virulence gene attenuation. The presence of conserved E. coli K-12 genes was examined using an E. coli K-12 strain MG1655-specific DNA array and the distribution of UPEC virulence-related genes was examined with the E. coli pathoarray. Two groups of strains could be distinguished. Several ABU strains were shown by multilocus sequence typing and by comparative genomic analyses to be related to UPEC but to have smaller genome sizes. There were significant alterations in essential virulence genes, including reductive evolution by point mutations, DNA rearrangements, and deletions. Other strains were unrelated to UPEC and lacked most of the virulence-associated genes. The results suggest that some ABU strains arise from virulent strains by attenuation of virulence genes while others are nonvirulent and resemble commensal strains. We propose that virulence attenuation might constitute a general mechanism for mucosal pathogens to evolve toward commensalism.     

Trends in drug resistance mutations in antiretroviral-naïve intravenous drug users of Rio de Janeiro

DNA sequencing of a pol gene fragment from drug-naive injecting drug users samples obtained at two time points of the Brazilian AIDS epidemic (Pre-HAART era: 1994 to early 1997, n = 27; post-HAART era: 1999-2001, n = 38) was undertaken to assess HIV-1 antiretroviral drug resistance mutations and subtyping profiles. Genotypic analysis revealed the presence of PR primary L90M, D30N, M46I, and V82A mutations in 7.9% of the post-HAART group, and a high frequency of secondary mutations (84.2%). Nucleoside RT-associated mutations were observed in 13.2%. In the pre-HAART group, a higher frequency of RT mutations was observed (22.2%) and no PR primary mutations were found, in agreement with the introduction of protease inhibitors (PIs) in therapy during the same period. The identification of 7.9% of drug-naive injecting drug users already bearing RT/PR primary resistance mutations in the post-HAART era group constitutes a major concern in terms of dissemination of drug resistant viruses. The resistance mutations profile of the individuals may reflect the context of antiretroviral treatment in Brazil at the sample collection periods (1994-1997 and 1999-2001). In spite of the differences observed in the drug resistance profiles, similar frequencies of subtype B (63.0 vs. 73.7%), F (22.2 vs. 10.5%), and recombinant B/F (14.8 vs. 15.8%) viruses were found, respectively, in the pre- and post-HAART groups.     

Multiple cryopreservation–warming cycles,coupled with blastocyst biopsy,negatively affect IVF outcomes

Research questionDo multiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes?DesignPatients undergoing IVF with homologous single embryo transfer, and who underwent trophectoderm biopsy for preimplantation genetic testing for aneuploidy (PGT-A) between 2013 and 2017, were divided into three groups based on degree of embryonic micromanipulation: once-biopsied, once-cryopreserved (group BC, n = 2603), once-biopsied, twice-cryopreserved (group CBC, n = 95) and twice-biopsied, twice-cryopreserved (group BCBC, n = 15). The primary outcome was live birth; secondary outcomes included positive serum pregnancy test, clinical pregnancy and miscarriage.ResultsGroup CBC had a significantly lower chance of live birth (adjusted RR 0.57, 95% CI 0.41 to 0.79) and clinical pregnancy (adjusted RR 0.67, 95% CI 0.53 to 0.85) compared with group BC. Miscarriage rates were similar between groups BC and CBC (adjusted RR 1.3, 95% CI 0.64 to 2.7).ConclusionsMultiple cryopreservation–warming cycles, coupled with blastocyst biopsy, negatively affect IVF outcomes. Although PGT-A is thought to improve reproductive outcomes on a per transfer basis, caution must be exercised in counselling patients on the possibility of diminishing returns owing to further embryonic micromanipulation after an embryo has been cryopreserved.     

Radiotherapy is not indicated in patients with vulvar squamous cell carcinoma and only one occult intracapsular groin node metastasis

ObjectiveMost guidelines advise no adjuvant radiotherapy in vulvar squamous cell carcinoma and a single occult intracapsular lymph node metastasis. However, several recent studies have questioned the validity of this recommendation. The aim of this study was to analyze the groin recurrence rate in patients with a single intracapsular positive lymph node treated without adjuvant radiotherapy.MethodsPatients with a single clinically occult intracapsular lymph node metastasis, treated without adjuvant radiotherapy, formed the basis for this study. Groin recurrences, and the risk of death, were analyzed in relation to the size of the metastasis in the lymph node and the lymph node ratio. Data were analyzed using SPSS, version 26.0 for Windows.ResultsAfter a median follow-up of 64 months, one of 96 patients (1%) was diagnosed with an isolated groin recurrence and another two (2.1%) were diagnosed with a combination of a local and a groin recurrence. The only isolated groin recurrence occurred in a contralateral lymph node negative groin. Size of the metastasis and lymph node ratio had no impact on the groin recurrence risk, nor on survival. The 5-year actuarial disease-specific and overall survivals were 79% and 62.5% respectively. The 5-year actuarial groin recurrence-free survival was 97%.ConclusionBecause of the low risk of groin recurrence and the excellent groin recurrence-free survival, we recommend that adjuvant radiotherapy to the groin in patients with vulvar squamous cell carcinoma and a single occult intracapsular lymph node metastasis can be safely omitted to prevent unnecessary toxicity and morbidity.     

Cervical carcinoma after negative Pap smears: evidence against rapid-onset cancers

Recently, suggestions have been made that a 'rapid-onset' type of cervical cancer is emerging. Evidence for this entity is based on the diagnosis of invasive cervical carcinoma within 2 or 3 years of a 'normal' Pap smear. Analysis of 237 patients presenting to our unit between November 1986 and July 1990 with the histologic diagnosis of invasive carcinoma of the cervix revealed 51 patients (21.5%) who reported having had a 'normal' Pap smear within 2 years of diagnosis. Strenuous efforts were made to verify and retrieve these smears in an attempt to isolate a group of 'rapid-onset' cancers. Despite the patients' claim to the contrary, there was no record of a smear being performed in 15 patients (29%). The slides of six patients could not be located either due to lack of laboratory co-operation or because the slides had been destroyed: four of these patients had very early adenocarcinomas. The slides of 30 patients were retrieved and reviewed: 16 slides reported as negative contained cells consistent with either invasive carcinoma or carcinoma in-situ; four cases had virtually no cellular material on the slide; four cases contained atypical cells but requests for further material were not followed-up. Six patients had previously been treated for pre-invasive lesions over a range of 3–18 years. We found no case of invasive carcinoma in a patient with a confirmed adequate negative smear within 2 years of diagnosis. At most, six patients (2.52%) could have had 'rapid-onset' cancers but this could not be confirmed as these slides could not be reviewed. In summary, this study suggests that in our patient population, 'rapid-onset' cervical carcinoma is rare.