Lisch Epithelial Corneal Dystrophy Is Caused by Heterozygous Loss-of-Function Variants in MCOLN1

PURPOSE

To report the genetic etiology of Lisch epithelial corneal dystrophy (LECD).

DESIGN

Multicenter cohort study.

METHODS

A discovery cohort of 27 individuals with LECD from 17 families, including 7 affected members from the original LECD family, 6 patients from 2 new families and 14 simplex cases, was recruited. A cohort of 6 individuals carrying a pathogenic MCOLN1 (mucolipin 1) variant was reviewed for signs of LECD. Next-generation sequencing or targeted Sanger sequencing were used in all patients to identify pathogenic or likely pathogenic variants and penetrance of variants.

RESULTS

Nine rare heterozygous MCOLN1 variants were identified in 23 of 27 affected individuals from 13 families. The truncating nature of 7 variants and functional testing of 1 missense variant indicated that they result in MCOLN1 haploinsufficiency. Importantly, in the homozygous and compound-heterozygous state, 4 of 9 LECD-associated variants cause the rare lysosomal storage disorder mucolipidosis IV (MLIV). Autosomal recessive MLIV is a systemic disease and comprises neurodegeneration as well as corneal opacity of infantile-onset with epithelial autofluorescent lysosomal inclusions. However, the 6 parents of 3 patients with MLIV confirmed to carry pathogenic MCOLN1 variants did not have the LECD phenotype, suggesting MCOLN1 haploinsufficiency may be associated with reduced penetrance and variable expressivity.

CONCLUSIONS

MCOLN1 haploinsufficiency is the major cause of LECD. Based on the overlapping clinical features of corneal epithelial cells with autofluorescent inclusions reported in both LECD and MLIV, it is concluded that some carriers of MCOLN1 haploinsufficiency-causing variants present with LECD.

Sustained effect of simulation-based ultrasound training on clinical performance: a randomized trial

OBJECTIVE

To study the effect of initial simulation-based transvaginal sonography (TVS) training compared with clinical training only, on the clinical performance of residents in obstetrics and gynecology (Ob-Gyn), assessed 2 months into their residency.

METHODS

In a randomized study, new Ob-Gyn residents (n = 33) with no prior ultrasound experience were recruited from three teaching hospitals. Participants were allocated to either simulation-based training followed by clinical training (intervention group; n = 18) or clinical training only (control group; n = 15). The simulation-based training was performed using a virtual-reality TVS simulator until an expert performance level was attained, and was followed by training on a pelvic mannequin. After 2 months of clinical training, one TVS examination was recorded for assessment of each resident's clinical performance (n = 26). Two ultrasound experts blinded to group allocation rated the scans using the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale.

RESULTS

During the 2 months of clinical training, participants in the intervention and control groups completed an average ± SD of 58 ± 41 and 63 ± 47 scans, respectively (P = 0.67). In the subsequent clinical performance test, the intervention group achieved higher OSAUS scores than did the control group (mean score, 59.1% vs 37.6%, respectively; P < 0.001). A greater proportion of the intervention group passed a pre-established pass/fail level than did controls (85.7% vs 8.3%, respectively; P < 0.001).

CONCLUSION

Simulation-based ultrasound training leads to substantial improvement in clinical performance that is sustained after 2 months of clinical training. © 2015 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology.

Reliable and valid assessment of ultrasound operator competence in obstetrics and gynecology

OBJECTIVES

To explore the reliability and validity of a recently developed instrument for assessment of ultrasound operator competence, the Objective Structured Assessment of Ultrasound Skills (OSAUS).

METHODS

Three groups of 10 doctors with different levels of ultrasound experience in obstetrics and gynecology were included. The novices had less than 1 month of experience, the intermediate group had 12-60 months of experience and the senior participants were all consultants. Fifteen participants performed transabdominal fetal biometry and the other 15 participants performed systematic transvaginal gynecological ultrasound scans. All scans were video-recorded and assessed by two blinded consultants using the OSAUS scale. The OSAUS scores were compared between the groups using the Kruskal-Wallis test, and pass/fail scores were determined using the contrasting-groups method of standard setting.

RESULTS

For the transabdominal fetal biometry examinations, the mean ± SD OSAUS scores of the novices, intermediates and senior participants were 1.5 ± 0.4, 3.3 ± 0.6 and 4.4 ± 0.4, respectively (P = 0.003). For the systematic transvaginal scans, the mean ± SD OSAUS scores of the novices, intermediates and senior participants were 1.8 ± 0.2, 3.1 ± 0.1 and 3.9 ± 0.5, respectively (P = 0.003). Post-hoc comparisons showed significant differences between each of the groups for both types of scans. The pass/fail score was 2.5 for the transvaginal scan and 3.0 for the transabdominal biometry examinations. The inter-rater reliability was 0.89.

CONCLUSIONS

Ultrasound competence can be assessed in a reliable and valid way using the OSAUS scale. The pass/fail scores may be used to help determine when trainees are qualified for independent practice.

Value of endometrial thickness measurement for diagnosing focal intrauterine pathology in women without abnormal uterine bleeding

OBJECTIVE

To assess the diagnostic value of transvaginal sonographic (TVS) measurement of endometrial thickness for diagnosing focal intrauterine pathology in women without abnormal uterine bleeding (AUB).

METHODS

A random selection from the Danish Civil Registration System was made: 1660 women aged 20-74 years were invited to participate and 686 women were eligible and accepted inclusion (429 pre- and 257 postmenopausal). The women underwent TVS measurement of endometrial thickness and saline contrast sonohysterography (SCSH). Hysteroscopic resection with histopathology (gold standard) was performed when focal intrauterine pathology was suspected at SCSH. We excluded women with AUB (n = 237), failure of SCSH (n = 50), a scan that was not in the follicular phase (n = 11), hysteroscopy contraindicated (n = 2), and users of sequential hormone therapy (n = 9) or selective estrogen receptor modulators (n = 2). Thus, 375 women without AUB were included (217 pre- and 158 postmenopausal). Receiver-operating characteristics (ROC) curves for endometrial thickness and focal lesion were analyzed.

RESULTS

Focal intrauterine pathology was confirmed in 41 women (35 with polyps, five with submucosal myomas and one with polypoidal growing cancer). For premenopausal women, the area under the ROC curve (AUC) was 0.79 (95% CI, 0.68-0.89) and for postmenopausal women it was 0.84 (95% CI, 0.76-0.92). For premenopausal women, the best negative likelihood ratio (LR- = 0.11) was obtained at an endometrial thickness of 5.2 mm, with a negative predictive value (NPV) of 99% and a positive predictive value (PPV) of 10%. For postmenopausal women the best LR- (0.08) was obtained at an endometrial thickness of 2.8 mm, with a NPV of 99% and a PPV of 26%.

CONCLUSIONS

In women without AUB, TVS measurement of endometrial thickness is a poor diagnostic test, but is apparently efficacious in excluding focal intrauterine pathology, especially in postmenopausal women. The 4-5-mm threshold conventionally used to exclude endometrial malignancy in women with postmenopausal bleeding is not transferable to women without AUB for excluding focal intrauterine pathology.

Prevalence of endometrial polyps and abnormal uterine bleeding in a Danish population aged 20-74 years

OBJECTIVE

To estimate the prevalence of endometrial polyps and to investigate associated abnormal uterine bleeding in a Danish population aged 20-74 years.

METHODS

This was a study of a random selection of women from the Danish Civil Registration System: 1660 women were invited of whom 686 were included (429 pre- and 257 postmenopausal). AUB was assessed by a validated questionnaire. The women underwent transvaginal sonography (TVS) and saline contrast sonohysterography (SCSH). Hysteroscopic resection was performed in cases with suspected focal intrauterine pathology. Full evaluation was performed in 619 women (two failures of TVS and 60 failures of SCSH, in two women SCSH was contraindicated (endometrial cancer), in two women hysteroscopy was contraindicated, and one polyp was lost before histology). World Health Organization histopathological criteria were used for diagnosing true endometrial polyps.

RESULTS

On final diagnosis there were 48 women with polyps, eight with submucosal myomas, four with other benign findings and one with polypoidal growing endometrial cancer. Complex hyperplasia without atypia was diagnosed in two women with polyps. The prevalence of endometrial polyps was 7.8% (48/619; 95% CI, 5.6-9.9%). The prevalence was influenced significantly by age (P<0.005); in women below the age of 30 years, the prevalence was 0.9%. Polyps were diagnosed in 5.8% of pre- and 11.8% of postmenopausal women (P<0.01). Thirty-nine (82%) of the women who had histopathologically verified polyps were asymptomatic. In asymptomatic premenopausal women the prevalence of polyps was 7.6%, while it was 13% in asymptomatic postmenopausal women. AUB, in particular intermenstrual bleeding, was more frequent among women without polyps (38%). By ultrasound examination, submucosal myomas were diagnosed in 4.2% (26/622; 95% CI, 2.6-5.8%) and intramural myomas in 11.1% (76/684; 95% CI, 8.8-13.5%) of women. Polyps were diagnosed in 2% of oral-contraceptive and 25% of hormone-therapy users.

CONCLUSIONS

The overall prevalence of endometrial polyps was 7.8% and the prevalence increased with age. Polyps were rare (0.9%) in women below the age of 30 years. Surprisingly, AUB was less frequent among women with polyps than among those without polyps.

Completeness and accuracy of voluntary reporting to a national case registry of laparoscopic cholecystectomy

OBJECTIVE

To validate completeness and accuracy of registry data reported from three randomly chosen departments contributing to The Danish National Registry of Laparoscopic Cholecystectomy, covering all departments offering chole cystectomy.

DATA SOURCES

A total of 431 case reports representing cases of laparoscopic cholecystectomy in a 2-year period in three surgical departments.

DESIGN

Comparison of case reports with reported data in The Danish National Registry of Laparoscopic Cholecystectomy.

MAIN OUTCOME MEASURES

Rates of discrepancies, comparison of complication rates for cases in the registry and cases not reported to the registry.

RESULTS

Completeness of registration was 69%, 80% and 99% respectively. A significantly higher degree of completeness was found in the only department with a formalized registration procedure. Inaccuracies were found in 28-49% of the cases, but none regarding serious complications such as bile duct injury or perioperative death.

CONCLUSIONS

The information in the national registry may be accurate if the present findings can be extrapolated to the remaining departments in the country. The number of non-reported cases should be minimized by introducing a formalized procedure of handling and forwarding information to the registry. Continuous validation through external visits by registry staff to contributing departments may also be advisable.