The impact of race and ethnicity on diffuse large B-cell lymphoma outcomes within the veterans health administration (VHA)

We performed a retrospective chart review of 6266 randomly selected DLBCL patients treated in the VHA nationwide between 1/1/2011 and 12/31/2021. The 3178 patients who met inclusion criteria were predominantly male (97%) and white (75%). Median age of diagnosis for Black patients was 63 years vs 69 years for the entire cohort (p < 0.001). However, patients in each race/ethnicity subgroup presented with similar rates of stage I/II and III/IV disease, IPI score, cell of origin and HIT status. Outcomes analysis revealed similar treatment, response rates, median overall survival, and 1-, 3-, and 5-year survival across all subgroups. Hispanic patients had a 21% lower risk of death (HR = 0.79) than white patients, and Black patients had no significant difference in survival (HR = 0.98). This large retrospective study shows that when standard of care therapy is given within an equal access system, short-term treatment and survival outcomes are the same for all races.

Impact of equal access by race and ethnicity on patients in the Veterans Health Administration (VHA) treated for diffuse large B-cell lymphoma (DLBCL)

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Background: Racial and ethnic disparities in access to care and outcomes are well-established and are critical issues across several malignancies, including DLBCL. Previous studies from national registry datasets have shown racial disparities in DLBCL disease characteristics, treatment and outcomes. The VHA is an equal access system providing a unique environment to investigate cancer disparities across the disease continuum. Methods: This is a retrospective chart review of 4033 randomly selected patients with an ICD code for lymphoma treated within the VHA between 01/01/2011 and 12/31/2017. Data abstractors collected baseline patient and disease characteristics and treatment responses for those with an initial diagnosis of DLBCL in that time frame. Survival time was determined via electronic health record query on 11/30/2021. Chi-square tests were used to analyze relationship between race and variables of interest. Cox proportional hazards model was used to estimate hazard ratios (HR) for race and controlling factors. Results: 2141 DLBCL patients met our inclusion criteria. 97% were male. Majority were Non-Hispanic Whites (NHW 75%) followed by Non-Hispanic Blacks (NHB 12.5%), Hispanics (H 5.7%) and others (O 6.8%). NHB were diagnosed at younger median age (63 years) when compared to the NHW, H and O (68 years). There was no statistically significant difference in stage at diagnosis, IPI score, cell of origin (COO) and hit status amongst racial subgroups. Outcomes analysis (Table) revealed similar treatment and response rates, median OS, 1- and 2- year survival across all racial subgroups. However, after adjusting for age, IPI, COO, and exposure to agent orange, and including up to 10-years of survival data, H had 36% lower risk of death (HR=0.64, 95% CI 0.44-0.93) than NHW, while NHB and O had similar outcomes to NHW. Conclusions: This large retrospective study is a continuation of our group’s work (Williams et al, 2020) that doubles the cohort size and confirms that when standard of care therapy is given with equal access to care, short-term treatment and survival outcomes are same for all races. Further studies are needed to analyze risk factors associated with differences in long term outcomes.[Table: see text]

Does ethnicity matter? A two-statewide population based analysis of outcomes of primary mediastinal B-cell lymphoma in Hispanics

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Background: Primary mediastinal B-cell lymphoma (PMBCL) is considered a rare distinct clinicopathological and molecular subtype of diffuse large B-cell lymphoma (DLBCL), mainly affecting females in their 4th and 5th decades [1,2,3]. Since the 1960s, there has been a significant increase in the number of immigrants to the US; and the states of Florida (FL) and Texas (TX) are well known for their Hispanic (HI) enriched population. Since there is scarce data of PMBCL in HI; we researched demographics, treatment patterns and outcomes in H compared to Non-Hispanics (NH) from FL and TX. Methods: This is a retrospective study of patients diagnosed with PMBCL from the Texas Cancer Registry (TCR) and the Florida Cancer Data System (FCDS), with years of analysis 2006-2017. Patients were identified by the International Classification of Diseases for Oncology Third Edition (ICD-O-3). Key variables collected included gender, race, ethnicity, dates at diagnosis and death, primary payer at diagnosis, stage, type of treatment, poverty index, and vitality status. The significance of variation in the distribution of categorical outcomes with ethnicity (H, NH) was assessed with Fisher’s Exact tests or Pearson’s Chi-square tests as appropriate. Survival distributions were described with Kaplan-Meier curves, and the significance of variation in median survival with ethnicity was assessed with log-rank testing. All statistical testing was two-sided with a significance level of 5%. Results: We had 2 cohorts; cohort A (A) includes 19 H vs. 89 NH from TX, cohort B (B), 27 H vs. 121 NH from FL. The median age at diagnosis in A was 33 years (y) in H vs 40 y in NH ( p-value = 0.091); while median age in B was 36 y in H vs 46 y in NH ( p-value = 0.005). Regarding poverty index; in A, most of H were in the 10-20% bracket, and most NH were in the 5-10% bracket. On the contrary, in B, most of H were in the 5-10%, and most NH were in the 10-20% bracket. Lack of insurance was more prevalent in H in A vs. NH, 42% vs. 12%, respectively, where it was less prevalent in H vs. NH in B, 8% vs. 5%. Multiple agents of chemotherapy were delivered to 74% of H, 70% of NH vs. 82% of H and 65% of NH with p-value = 0.292 and 0.635 in A and B, respectively. In A, the NH had better median survival (m) than H, not reached vs. 10.3 y, respectively. In B, H had better m than the NH, 10.7 y vs. not reached, respectively. The 5 y survival probability in A was even among H and NH; 0.702 [95% CI 0.49-1] and 0.732 [95% CI 0.578 - 0.9280], respectively. While 5 y survival probability in B was higher in H compared to NH, 0.923 [95% CI 0.675 -0.869] and 0.766 [95% CI 0.434 - 0.615], respectively. The overall survival (OS) difference in A and B, H vs. NH was not statistically significant. Conclusions: Despite some identified demographic differences in patients diagnosed with PMBCL, comparing H vs. NH on each cohort, there was no statistically significant difference in the overall survival probability.

Optimizing Small, Low-Risk, Unruptured Intracranial Aneurysm Treatment Using Game Theory

The incidental diagnosis of unruptured intracranial aneurysms has been increasing in the past several decades. A significant proportion represent small, low-risk, unruptured intracranial aneurysms for which there is equipoise on whether to offer treatment or conservative management. Given this uncertainty, patients may not always be comfortable with their physicians' recommendations. Herein, we use game theory to study the interactions between physicians and patients to determine how conflict and cooperation affect the management of small, low-risk, unruptured intracranial aneurysms. We constructed a game theory model of the interaction between physicians and patients with respect to decision-making for a small, low-risk, unruptured intracranial aneurysm in an asymptomatic patient when there is perceived equipoise between whether to treat or manage conservatively. Assuming that both the physician and patient are rational and eliciting individual patient preferences is not practical, the physician should play the game based on an ex ante probability of meeting a patient with a certain type of preference. This recommendation means that the expectations of the physician regarding the patient's preferences should guide the decision to offer treatment or conservative management as a first option for a small, asymptomatic, low-risk, unruptured intracranial aneurysm for which there is clinical equipoise.

Low vitamin D levels and prognosis in a COVID-19 pediatric population: a systematic review

We aim to study the relationship between vitamin D level, risk and severity of Coronavirus disease of 2019 (COVID-19) infection in pediatric population through systematic review. We searched PubMed, CINAHL, EMBASE, Cochrane Library and Google Scholar from December 2019 to June 2021 for retrieving articles studying association between vitamin D deficiencies with COVID-19. Qualitative details were synthesized in evidence table and quantitative data was used for deriving pooled estimate through meta-analysis. After initial search of 2261 articles, eight eligible studies (two reviews) were included in the systematic review. Meta-analysis of the quantitative data (six studies) showed pooled prevalence of vitamin D deficiency as 45.91% (95% CI: 25.148-67.450). In infected pediatric patients, low levels of vitamin D increased the risk of severe disease (odds ratio-5.5; 95% CI: 1.560-19.515; P = 0.008). It was also found that children and adolescents having vitamin D deficiency had greater risk of COVID infection as compared to patients with normal vitamin D levels. Improvement in disease severity with vitamin D supplementation was also noted. The systematic review showed that almost half of the pediatric COVID patients suffer from vitamin D deficiency. It is also clear that the low level of vitamin D is associated with greater risk of infection and poorer outcome in pediatrics.

Rescan Time Delays in Ischemic Stroke Imaging: A Retrospective Observation and Analysis of Causes and Clinical Impact

BACKGROUND AND PURPOSE

Delays to reperfusion negatively impact outcomes of patients with ischemic stroke, yet current guidelines recommend selective sequential imaging for thrombectomy candidates. We aimed to quantify and analyze time delays associated with rescanning in sequential acute stroke imaging.

MATERIALS AND METHODS

This was a retrospective cohort study of consecutive patients with acute ischemic stroke who underwent imaging for treatment decision-making from January 1, 2017, to June 30, 2020. Rescan time delay was defined as ≥10-minute difference between initial NCCT and CTA ± CTP. Mean rescan time delays in comprehensive and primary stroke centers were compared. Bivariate and multivariable regression analyses assessed clinical and imaging factors associated with rescanning time delays and early outcomes.

RESULTS

A total of 588 patients with acute ischemic were included in statistical analyses. Rescanning occurred in 27.9% (164/588 patients), with a mean time delay of 53.7 (SD, 43.4) minutes. For patients presenting at primary compared with comprehensive stroke centers, rescan time delays were more common (59.6% versus 11.8%, P < .001), with longer delays (65.4 [SD, 45.4] minutes versus 23.6 [SD, 14.0] minutes, P < .001). Independent predictors of rescan time delays included primary stroke center presentation, intravenous thrombolysis administration, black race, admission NIHSS ≥10, baseline independent ambulation, and onset-to-comprehensive stroke center arrival in ≥6 hours. Protocols for early simultaneous comprehensive CT (NCCT + CTA + CTP) were associated with lower odds of time delays (OR = 0.34; 95% CI, 0.21-0.55). Rescanning was associated with lower odds of home discharge (OR = 0.53; 95% CI, 0.30-0.95).

CONCLUSIONS

A sequential approach to CT-based imaging may be significantly associated with prolonged acute stroke evaluations. Adoption of early simultaneous comprehensive CT could minimize treatment delays and improve outcomes.

Assessing the demographics of fertility preservation discussions in cancer patients

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Background: Young adults undergoing cancer treatment often face increased risk of infertility. Despite current ASCO guidelines recommending prompt fertility preservation education, knowledge about prevalence and barriers to oncofertility care is lacking. This is particularly true for patients in medically underserved and minority communities. This study sought to characterize the utilization of oncofertility counseling in a major Hispanic serving institution. Methods: Retrospective chart review was performed at the University of Texas Mays Cancer Center San Antonio and included patients diagnosed with testicular, early stage breast cancer or leukemia/lymphoma between age 18-40 from 2015-2019. Demographic data including ethnicity, race, funding, zip code were collected. Chart reviewed determined if fertility counseling was provided and which patients elected for oncofertility treatments. Results: Of 304 evaluable patients, only 120 had documented fertility discussions. There was no significant difference in the odds of counseling between gender, funding, or race. However, the odds of receiving fertility discussions was higher in non-Hispanic whites compared to Hispanic whites with an odds ratio of 1.94 (P value of 0.032). For those who opted for fertility treatment there was no statistically significant difference between diagnosis, race, ethnicity, or payment status. Conclusions: Our study demonstrates oncofertility discussions occur in a relatively small proportion of eligible patients. Additionally, patients who self -identify as Hispanic were less likely to receive fertility discussions. This study demonstrates that more research is necessary to evaluate the barriers to fertility discussion and treatment, and how these barriers result in decreased oncofertility education in Hispanic young adults with curable malignancies. [Table: see text]

Effects of Radiation Exposure on the Cost-Effectiveness of CT Angiography and Perfusion Imaging in Aneurysmal Subarachnoid Hemorrhage

BACKGROUND AND PURPOSE

CT angiography and perfusion imaging is an important prognostic tool in the management of patients with aneurysmal subarachnoid hemorrhage. The purpose of this study was to perform a cost-effectiveness analysis of advanced imaging in patients with SAH, incorporating the risks of radiation exposure from CT angiography and CT perfusion imaging.

MATERIALS AND METHODS

The risks of radiation-induced brain cancer and cataracts were incorporated into our established decision model comparing the cost-effectiveness of CT angiography and CT perfusion imaging and transcranial Doppler sonography in SAH. Cancer risk was calculated by using National Cancer Institute methodology. The remaining input probabilities were based on literature data and a cohort at our institution. Outcomes were expected quality-adjusted life years gained, costs, and incremental cost-effectiveness ratios. One-way, 2-way, and probabilistic sensitivity analyses were performed.

RESULTS

CT angiography and CT perfusion imaging were the dominant strategies, resulting in both better health outcomes and lower costs, even when incorporating brain cancer and cataract risks. Our results remained robust in 2-way sensitivity analyses varying the prolonged latency period up to 30 years, with either brain cancer risk up to 50 times higher than the upper 95% CI limit or the probability of cataracts from 0 to 1. Results were consistent for scenarios that considered either symptomatic or asymptomatic patients with SAH. Probabilistic sensitivity analysis confirmed our findings over a broad range of selected input parameters.

CONCLUSIONS

While risks of radiation exposure represent an important consideration, CT angiography and CT perfusion imaging remained the preferred imaging compared with transcranial Doppler sonography in both asymptomatic and symptomatic patients with SAH, with improved health outcomes and lower health care costs, even when modeling a significantly higher risk and shorter latency period for both cataract and brain cancer than that currently known.

CT angiographic features of symptom-producing plaque in moderate-grade carotid artery stenosis

BACKGROUND AND PURPOSE

Emerging evidence indicates that plaque imaging can improve stroke risk stratification in patients with carotid artery atherosclerosis. We studied the association between soft and hard (calcified) plaque thickness measurements on CTA and symptomatic disease status (ipsilateral stroke or TIA) in patients with moderate-grade carotid artery stenosis.

MATERIALS AND METHODS

We measured soft-plaque and hard-plaque thickness on CTA axial source images in each carotid artery plaque in subjects with NASCET 50%-69% ICA stenosis. We used logistic regression and receiver operating characteristic analyses to assess the strength of the association between thickness measurements and prior stroke or TIA.

RESULTS

Twenty of 72 vessels studied (27.7%) had ischemic symptoms ipsilateral to the side of moderate-grade carotid stenosis. Each 1-mm increase in soft plaque resulted in a 3.7 times greater odds of a prior ipsilateral ischemic event (95% CI, 1.9-7.2). Conversely, for each 1-mm increase in hard plaque, the odds of being symptomatic decreased by approximately 80% (OR, 0.22; 95% CI, 0.10%-0.48%). Receiver operating characteristic analysis showed an area under the curve of 0.88 by using soft-plaque thickness measurements to discriminate between asymptomatic and symptomatic plaques. Sensitivity and specificity were optimized by using a maximum soft-plaque thickness of 2.2 mm, which provided a sensitivity of 85% and a specificity of 83%.

CONCLUSIONS

Simple CTA plaque-thickness measurements might differentiate symptomatic and asymptomatic moderate-grade carotid artery plaque. With further prospective validation, CTA plaque measures could function as an easily implementable tool for risk stratification in carotid artery disease.

Cost-effectiveness of CT angiography and perfusion imaging for delayed cerebral ischemia and vasospasm in aneurysmal subarachnoid hemorrhage

BACKGROUND AND PURPOSE

Delayed cerebral ischemia and vasospasm are significant complications following SAH leading to cerebral infarction, functional disability, and death. In recent years, CTA and CTP have been used to increase the detection of delayed cerebral ischemia and vasospasm. Our aim was to perform comparative-effectiveness and cost-effectiveness analyses evaluating CTA and CTP for delayed cerebral ischemia and vasospasm in aneurysmal SAH from a health care payer perspective.

MATERIALS AND METHODS

We developed a decision model comparing CTA and CTP with transcranial Doppler sonography for detection of vasospasm and delayed cerebral ischemia in SAH. The clinical pathways were based on the "Guidelines for the Management of Aneurysmal Subarachnoid Hemorrhage: A Guideline for Healthcare Professionals from the American Heart Association/American Stroke Association" (2012). Outcome health states represented mortality and morbidity according to functional outcomes. Input probabilities of symptoms and serial test results from CTA and CTP, transcranial Doppler ultrasound, and digital subtraction angiography were directly derived from an SAH cohort by using a multinomial logistic regression model. Expected benefits, measured as quality-adjusted life years, and costs, measured in 2012 US dollars, were calculated for each imaging strategy. Univariable, multivariable, and probabilistic sensitivity analyses were performed to determine the independent and combined effect of input parameter uncertainty.

RESULTS

The transcranial Doppler ultrasound strategy yielded 13.62 quality-adjusted life years at a cost of $154,719. The CTA and CTP strategy generated 13.89 quality-adjusted life years at a cost of $147,097, resulting in a gain of 0.27 quality-adjusted life years and cost savings of $7622 over the transcranial Doppler ultrasound strategy. Univariable and multivariable sensitivity analyses indicated that results were robust to plausible input parameter uncertainty. Probabilistic sensitivity analysis results yielded 96.8% of iterations in the right lower quadrant, representing higher benefits and lower costs.

CONCLUSIONS

Our model results suggest that CTA and CTP are the preferred imaging strategy in SAH, compared with transcranial Doppler ultrasound, leading to improved clinical outcomes and lower health care costs.

Oxygen extraction fraction and stroke risk in patients with carotid stenosis or occlusion: a systematic review and meta-analysis

BACKGROUND AND PURPOSE

Increased oxygen extraction fraction on PET has been considered a risk factor for stroke in patients with carotid stenosis or occlusion, though the strength of this association has recently been questioned. We performed a systematic review and meta-analysis to summarize the association between increased oxygen extraction fraction and ipsilateral stroke risk.

MATERIALS AND METHODS

A comprehensive literature search was performed. We included studies with baseline PET oxygen extraction fraction testing, ipsilateral stroke as the primary outcome, and at least 1 year of follow-up. A meta-analysis was performed by use of a random-effects model.

RESULTS

After screening 2158 studies, 7 studies with 430 total patients with mean 30-month follow-up met inclusion criteria. We found that 6 of 7 studies were amenable to meta-analysis. Although 4 of the 6 studies independently did not reach statistical significance, meta-analysis revealed a significant positive relationship between abnormal oxygen extraction fraction and future ipsilateral stroke, with a pooled OR of 6.04 (95% CI, 2.58-14.12). There was no statistically significant difference in OR in the subgroup analyses according to testing method or disease site.

CONCLUSIONS

Abnormal oxygen extraction fraction remains a powerful predictor of stroke in carotid stenosis or occlusion and is a valuable reference standard to compare and validate MR imaging-based measures of brain oxygen metabolism. However, there is a need for further evaluation of oxygen extraction fraction testing in patients with high-grade but asymptomatic carotid disease.

Intraplaque high-intensity signal on 3D time-of-flight MR angiography is strongly associated with symptomatic carotid artery stenosis

BACKGROUND AND PURPOSE

Intraplaque hemorrhage in carotid artery atherosclerotic plaque has been shown to be a marker of risk, associated with prior and future ischemic events, and has been associated with regions of intraplaque high-intensity signal on 3D-TOF MRA. We assessed the association of intraplaque high-intensity signal determined on 3D-TOF MRA with the incidence of prior ipsilateral stroke or TIA.

MATERIALS AND METHODS

We assessed intraplaque hemorrhage by evaluating for intraplaque high-intensity signal adapting a recently validated technique on 3D-TOF source images in participants with high-grade (≥ 70%) extracranial carotid stenosis. Logistic regression analyses were used to assess the strength of association between the presence of intraplaque high-intensity signal on routine MRA sequences and prior stroke or TIA.

RESULTS

Intraplaque high-intensity signal was present in 22 (41.5%) of 53 carotid arteries studied in 51 patients. Ipsilateral ischemic events occurred in 15 (68.1%) of 22 in the intraplaque high-intensity signal-positive group (10 strokes, 5 TIAs) and in 4 (12.9%) of 31 in the intraplaque high-intensity signal-negative group (3 strokes, 1 TIA). Ischemic events occurred within the 6-month period preceding imaging in 18 (94.7%) of 19 cases. The univariate odds ratio of the association of intraplaque high-intensity signal with any prior ischemic event was 14.5 (95% CI, 3.6-57.6), and the multivariate age- and sex-adjusted odds ratio was 14.2 (95% CI, 3.3-60.5). The association remained present across 1.5 T and 3T magnet field strengths.

CONCLUSIONS

Intraplaque high-intensity signal determined from MRA sequences already in place to measure luminal stenosis is strongly associated with prior ipsilateral ischemic events. Prospective validation of these findings to predict outcome in carotid artery stenosis could provide a valuable and widely accessible stroke risk stratification tool.

A novel DFNB1 deletion allele supports the existence of a distant cis-regulatory region that controls GJB2 and GJB6 expression

Eleven affected members of a large German-American family segregating recessively inherited, congenital, non-syndromic sensorineural hearing loss (SNHL) were found to be homozygous for the common 35delG mutation of GJB2, the gene encoding the gap junction protein Connexin 26. Surprisingly, four additional family members with bilateral profound SNHL carried only a single 35delG mutation. Previously, we demonstrated reduced expression of both GJB2 and GJB6 mRNA from the allele carried in trans with that bearing the 35delG mutation in these four persons. Using array comparative genome hybridization (array CGH), we have now identified on this allele a deletion of 131.4 kb whose proximal breakpoint lies more than 100 kb upstream of the transcriptional start sites of GJB2 and GJB6. This deletion, del(chr13:19,837,344-19,968,698), segregates as a completely penetrant DFNB1 allele in this family. It is not present in 528 persons with SNHL and monoallelic mutation of GJB2 or GJB6, and we have not identified any other candidate pathogenic copy number variation by arrayCGH in a subset of 10 such persons. Characterization of distant GJB2/GJB6 cis-regulatory regions evidenced by this allele may be required to find the 'missing' DFNB1 mutations that are believed to exist.

Transpupillary thermotherapy (TTT) for age-related macular degeneration

PURPOSE

To review the results of transpupillary thermotherapy (TTT) on choroidal neovascular membranes associated with age-related macular degeneration (AMD).

MATERIALS AND METHODS

35 eyes of 35 patients with AMD and choroidal neovascularization and exudation were treated with TTT and had fundus photographs and fluorescein angiography (FA) before and at least six months after TTT. 28 eyes had predominantly occult lesions as seen on FA, while 7 demonstrated primarily classic lesions. All were treated with 650mw power or less using the 810 nm diode laser (3000 micron spot, duration of 60 seconds). Visual acuity, lesion size, and amount of subretinal fluid were determined by results of examination and review of photographs and fluorescein angiograms.

RESULTS

A 50% reduction in subretinal fluid was achieved in 67% of treated eyes overall, with stabilization of vision (less than three lines of visual acuity lost) in 86%. Complications from treatment were infrequent (9%) and involved hemorrhage noted in the region of treatment upon follow-up.

CONCLUSION

TTT promotes resolution of subretinal fluid and appears to stabilize visual acuity in patients with exudative AMD.

Connective tissue and related disorders and preterm birth: clues to genes contributing to prematurity

To identify candidate genes contributing to preterm birth, we examined the existing literature on the association between known disorders of connective tissue synthesis and metabolism and related diseases and prematurity. Our hypothesis was that abnormal matrix metabolism contributes to prematurity by increasing risk of preterm premature rupture of membranes (PPROM) and cervical incompetence. Based on this review, we identified gene mutations inherited by the fetus that could predispose to preterm birth as a result of PPROM. The responsible genes include COL5A1, COL5A2, COL3A1, COL1A1, COL1A2, TNXB, PLOD1, ADAMTS2, CRTAP, LEPRE1 and ZMPSTE24. Marfan syndrome, caused by FBN1 mutations, and polymorphisms in the COL1A1 and TGFB1 genes have been associated with cervical incompetence. We speculate that an analysis of sequence variation at the loci noted above will reveal polymorphisms that may contribute to susceptibility to PPROM and cervical incompetence in the general population.

Guidelines for clinical trials in melasma. Pigmentation Disorders Academy

There have been very few well-conducted trials in melasma and this makes the process of comparing treatment outcome between trials difficult. The Pigmentary Disorders Academy has examined the issues relating to clinical trials on melasma, and has proposed recommendations on how they should be conducted. This covers all aspects including correct diagnosis of the condition, evaluation of efficacy and safety outcome, and overall clinical trial design. It is anticipated that the establishment of accepted guidelines on the conduct of clinical trials in melasma will greatly assist the dermatological community.

A novel locus for autosomal dominant non-syndromic deafness, DFNA53, maps to chromosome 14q11.2-q12

BACKGROUND

Non-syndromic hearing loss is among the most genetically heterogeneous traits known in humans. To date, at least 50 loci for autosomal dominant non-syndromic sensorineural hearing loss (ADNSSHL) have been identified by linkage analysis.

OBJECTIVE

To report the mapping of a novel autosomal dominant deafness locus on the long arm of chromosome 14 at 14q11.2-q12, DFNA53, in a large multigenerational Chinese family with post-lingual, high frequency hearing loss that progresses to involve all frequencies.

RESULTS

A maximum multipoint LOD score of 5.4 was obtained for marker D14S1280. The analysis of recombinant haplotypes mapped DFNA53 to a 9.6 cM region interval between markers D14S581 and D14S1021. Four deafness loci (DFNA9, DFNA23, DFNB5, and DFNB35) have previously been mapped to the long arm of chromosome 14. The critical region for DFNA53 contains the gene for DFNA9 but does not overlap with the regions for DFNB5, DFNA23, or DFNB35. Screening of the COCH gene (DFNA9), BOCT, EFS, and HSPC156 within the DFNA53 interval did not identify the cause for deafness in this family.

CONCLUSIONS

Identifying the DFNA53 locus is the first step in isolating the gene responsible for hearing loss in this large multigeneration Chinese family.

Adhesive retention dressings are more comfortable than alginate dressings on split-skin-graft donor sites

Painful split-skin-graft donor sites remain a common problem for patients. We undertook a prospective randomised trial to examine the comparative comfort and ease of care of two different donor-site dressings. One dressing is the alginate Kaltostat, the standard plastic-surgical dressing in the UK and abroad, and the other is the adhesive retention tape Mefix, a novel use of a readily available dressing. We randomised 50 patients requiring split-skin grafts to receive either alginate (Kaltostat) or retention (Mefix) donor-site dressings. Dressings were assessed by interview and questionnaire at 24, 72 h and 2 weeks, and by wound review at 2 weeks. Retention dressings were found to be more comfortable, required less nursing intervention and allowed patients easier mobility with a greater range of daily activities, especially washing, without compromising wound healing. We recommend adhesive retention dressings as cost-effective comfortable dressings, which readily conform to any donor site.

Origins and frequencies of SLC26A4 (PDS) mutations in east and south Asians: global implications for the epidemiology of deafness

Recessive mutations of SLC26A4 (PDS) are a common cause of Pendred syndrome and non-syndromic deafness in western populations. Although south and east Asia contain nearly one half of the global population, the origins and frequencies of SLC26A4 mutations in these regions are unknown. We PCR amplified and sequenced seven exons of SLC26A4 to detect selected mutations in 274 deaf probands from Korea, China, and Mongolia. A total of nine different mutations of SLC26A4 were detected among 15 (5.5%) of the 274 probands. Five mutations were novel and the other four had seldom, if ever, been identified outside east Asia. To identify mutations in south Asians, 212 Pakistani and 106 Indian families with three or more affected offspring of consanguineous matings were analysed for cosegregation of recessive deafness with short tandem repeat markers linked to SLC26A4. All 21 SLC26A4 exons were PCR amplified and sequenced in families segregating SLC26A4 linked deafness. Eleven mutant alleles of SLC26A4 were identified among 17 (5.4%) of the 318 families, and all 11 alleles were novel. SLC26A4 linked haplotypes on chromosomes with recurrent mutations were consistent with founder effects. Our observation of a diverse allelic series unique to each ethnic group indicates that mutational events at SLC26A4 are common and account for approximately 5% of recessive deafness in south Asians and other populations.

The re-attachment of tendon and ligament avulsions

This paper presents our experience of a new technique for the reattachment of tendons in the hand. A percutaneous Kirschner wire is fashioned into a hoop to support an intratendinous suture. This mechanism maintains continuous traction upon the avulsed tendon. The technique avoids extensive dissection of the fingertip and the direct application of pressure on the dorsal surface of the digit, which might cause skin breakdown.

A novel locus for autosomal dominant non-syndromic deafness (DFNA41) maps to chromosome 12q24-qter

We have studied 36 subjects in a large multigenerational Chinese family that is segregating for an autosomal dominant adult onset form of progressive non-syndromic hearing loss. All affected subjects had bilateral sensorineural hearing loss involving all frequencies with some significant gender differences in initial presentation. After excluding linkage to known loci for non-syndromic deafness, we used the Center for Inherited Disease Research (CIDR) to test for 351 polymorphic markers distributed at approximately 10 cM intervals throughout the genome. Analysis of the resulting data provided evidence that the locus designated DFNA41 maps to a 15 cM region on chromosome 12q24.32-qter, proximal to the marker D12S1609. A maximum two point lod score of 6.56 at theta=0.0 was obtained for D12S343. This gene is distal to DFNA25, a previously identified locus for dominant adult onset hearing loss that maps to 12q21-24. Positional/functional candidate genes in this region include frizzled 10, epimorphin, RAN, and ZFOC1.

Mutations in GJA1 (connexin 43) are associated with non-syndromic autosomal recessive deafness

Mutations in four members of the connexin gene family have been shown to underlie distinct genetic forms of deafness, including GJB2 [connexin 26 (Cx26)], GJB3 (Cx31), GJB6 (Cx30) and GJB1 (Cx32). We have found that alterations in a fifth member of this family, GJA1 (Cx43), appear to cause a common form of deafness in African Americans. We identified two different GJA1 mutations in four of 26 African American probands. Three were homozygous for a Leu-->Phe substitution in the absolutely conserved codon 11, whereas the other was homozygous for a Val-->Ala transversion at the highly conserved codon 24. Neither mutation was detected in DNA from 100 control subjects without deafness. Cx43 is expressed in the cochlea, as is demonstrated by PCR amplification from human fetal cochlear cDNA and by RT-PCR of mouse cochlear tissues. Immunohistochemical staining of mouse cochlear preparations showed immunostaining for Cx43 in non-sensory epithelial cells and in fibrocytes of the spiral ligament and the spiral limbus. To our knowledge this is the first alpha connexin gene to be associated with non-syndromic deafness. Cx43 must also play a critical role in the physiology of hearing, presumably by participating in the recycling of potassium to the cochlear endolymph.

De novo inverted tandem duplication of the short arm of chromosome 12 in a patient with microblepharon

We present a patient with a de novo inverted duplication of nearly the entire short arm of chromosome 12 [inv dup(12)(p13.3p12)], which was characterized using GTG-banding and spectral karyotyping. The patient was noted to have microblepharon, which has not been previously described in children with a similar chromosomal rearrangement. This patient represents one of the few examples of complete and pure trisomy 12p due to inverted duplication of the short arm of chromosome 12 and expands the clinical spectrum.

Waardenburg syndrome type 3 (Klein-Waardenburg syndrome) segregating with a heterozygous deletion in the paired box domain of PAX3: a simple variant or a true syndrome?

Klein-Waardenburg syndrome or Waardenburg syndrome type 3 (WS-III; MIM 148820) is characterized by the presence of musculoskeletal abnormalities in association with clinical features of Waardenburg syndrome type 1 (WS-I). Since the description of the first patient in 1947 (D. Klein, Arch Klaus Stift Vererb Forsch 1947: 22: 336-342), a few cases have been reported. Only occasional families have demonstrated autosomal-dominant inheritance of WS-III. In a previous report, a missense mutation in the paired domain of the PAX3 gene has been described in a family with dominant segregation of WS-III. In this report, we present a second family (mother and son) with typical clinical findings of WS-III segregating with a heterozygous 13-bp deletion in the paired domain of the PAX3 gene. Although homozygosity or compound heterozygosity has also been documented in patients with severe limb involvement, a consistent genotype-phenotype correlation for limb abnormalities associated with heterozygous PAX3 mutations has not previously been apparent. Heterozygous mutations could either reflect a unique dominant-negative effect or possibly the contribution of other unlinked genetic modifiers in determining the phenotype.

Advances in hereditary deafness

Progress in the Human Genome Project, availability of cochlea-specific cDNA libraries, and development of murine models of deafness have resulted in rapid discovery of many loci and corresponding genes for deafness. Up to now, the chromosomal locations of about 70 genes for non-syndromic deafness have been mapped, and the genes of more than 20 loci have been identified and characterised. Mutations in one gene, connexin 26 (CX26GJB2), are responsible for most cases of recessive non-syndromic deafness, accounting for 30-40% of all childhood genetic deafness in some populations (eg, white people of western European descent). We summarise advances in identification of genes for deafness and provide a guide to the clinical approach to diagnosis of patients with hearing loss.

Haplotype analysis of the USH1D locus and genotype-phenotype correlations

Usher syndrome (USH) is characterised by hearing impairment and progressive pigmentary retinopathy. USH can be divided into three subtypes based on the severity and progression of the major clinical findings. These subtypes are genetically heterogeneous, with at least six loci for USH1, three for USH2 and one for USH3. In the present study, five unrelated consanguineous families with USH1 were analysed for linkage to markers flanking the six USH1 loci. Two of these families, one Pakistani and one Turkish, demonstrated linkage to the USH1D locus. In another family, haplotype segregation was consistent with linkage to USH1C. The remaining families were not linked to any of the six USH1 loci, providing support for the existence of at least one additional USH1 locus. Analysis of these two new USH1D families allowed us to narrow the USH1D candidate region to a 7.3-cM interval with a telomeric flanking marker at D10S1752. Comparison of the affected haplotypes in our Pakistani family with the original Pakistani USH1D family yielded no evidence for a founder effect. The identification of two additional affected families suggests that the USH1D may be a more common form of USH1 than originally suspected. The USH1D (CDH23) gene has recently been cloned. Mutation analysis has shown two different CDH23 mutations in the two Pakistani USH1D families studied, which confirmed our finding that there was no evidence for a founder effect by haplotype analysis. The interesting correlations between genotype and phenotype in CDH23 are also summarised.