Validation of screening instruments for common mental disorders and suicide risk in south African primary care settings.

INTRODUCTION: In South Africa, there is limited mental health infrastructure and resources. Valid screening tools are needed to facilitate identification and linkage to care. We evaluated the performance of Patient Health Questionnaire-9 (PHQ-9), Generalized Anxiety Disorder-7 (GAD-7), Primary Care Post Traumatic Stress Disorder Screen for DSM-5 (PC-PTSD-5), and the Columbia Suicide Severity Rating Scale (C-SSRS) among adults in South Africa against a diagnostic gold standard. METHODS: Adults present at healthcare facilities were screened with the PHQ-9, GAD-7, PC-PTSD-5, and the C-SSRS. Nurses used a structured diagnostic interview to identify depression, anxiety, panic disorder, PTSD and elevated suicide risk. We assessed the internal consistency, criterion validity, and the sensitivity and specificity of these tools. RESULTS: Of the 1885 participants, the prevalence of common mental disorders and suicide risk was 24.4 % and 14.9 %, respectively. The PHQ-9, GAD-7, and PC-PTSD-5 showed good internal consistency (0.80-0.89). All screeners demonstrated good criterion validity. For depression, a cut-off of ≥5 on the PHQ-9 yielded sensitivity of 84.24 %, while ≥10 yielded sensitivity of 48.77 %. For anxiety, the GAD-7 performed similarly. A cut-off of ≥4 on the PC-PTSD yielded sensitivity of 61.96 %. The C-SSRS yielded lower sensitivity than expected. LIMITATIONS: The prevalence data is not generalizable to the larger South African adult population given the use of a targeted, healthcare facility-based sampling and recruitment strategy. CONCLUSIONS: The performance of the PHQ-9, GAD-7, and PC-PTSD-5 demonstrated good internal consistency and criterion validity, though sensitivity and specificity trade-offs were enhanced with lower cut-offs. Further research into suicide risk screening is warranted.

Validation of a brief screener for broad-spectrum mental and substance-use disorders in South Africa.

In low-resource settings, valid mental health screening tools for non-specialists can be used to identify patients with psychiatric disorders in need of critical mental health care. The Mental Wellness Tool-13 (mwTool-13) is a 13-item screener for identifying adults at risk for common mental disorders (CMDs) alcohol-use disorders (AUDs), substance-use disorders (SUD), severe mental disorders (SMDs), and suicide risk (SR). The mwTool-13 is administered in two steps, specifically, only those who endorse any of the initial three questions receive the remaining ten questions. We evaluated the performance of mwTool-13 in South Africa against a diagnostic gold standard. We recruited a targeted, gender-balanced sample of adults, aged ≥18 years at primary and tertiary healthcare facilities in Eastern Cape Province. Of the 1885 participants, the prevalence of CMD, AUD, SMD, SR, and SUD was 24.4%, 9.5%, 8.1%, 6.0%, and 1.6%, respectively. The mwTool-13 yielded high sensitivities for CMD, SMD, and SR, but sub-optimal sensitivities for AUD and SUD (56.7% and 64.5%, respectively). Including a single AUD question in the initial question set improved the tool's performance in identifying AUD and SUD (sensitivity > 70%), while maintaining brevity, face-validity, and simplicity in the South African setting.

COVID-19 pandemic's effects and telehealth in Early Psychosis Services of Quebec, Canada: Will changes last?

AIM: To explore the impacts of the COVID-19 pandemic first wave in Quebec, Canada on practices in early intervention services (EIS) for first-episode psychosis, including reorganization of clinical and administrative practices and teleconsultation use. METHODS: Adopting a cross-sectional descriptive study design, a 41 questions online survey was sent to the team leaders of all the 33 Quebec EIS, of which 100% responded. Data were collected from 18 May to 4 June 2020 and analysed using descriptive statistics and content analysis. Programmes were categorized as urban/non-urban and results were compared between these. RESULTS: All 33 existing Quebec EIS (16 urban and 17 non-urban) completed the survey. Among them, 85% did not experience redeployment of EIS team staff and 58% reported stable frequency of patient interactions, either in-person or through telemedicine. During the studied period, 64% of programmes reported that all professionals used teleconsultation at least occasionally. However, 73% of programmes, mostly in non-urban areas, reported some limitations regarding clinicians' degree of ease with teleconferencing platforms and half of EIS could not access technical support to use them. The majority of EIS (94%) expressed interest to participate in a training program about the use of technologies for teleconsultations. Many smaller clinics reported interest in offering multiregional/multiclinics group teletherapy, therefore merging their pool of patients and clinical staff workforce. CONCLUSIONS: Further studies are warranted to improve access to and use of technology-mediated treatment, which seems to be a promising alternative to provide high-quality mental healthcare during the COVID-19 pandemic and beyond.

[From Kraepelin to McGorry: Scientific Vision and Experiential Narrative around a Major Paradigmatic Shift]. / De Kraepelin à McGorry : vision scientifique et récit expérientiel autour d'un changement de paradigme majeur.

Objectives Until the early 1990s, a pessimistic view of psychotic disorders, based on the Kraepelinian perspective, prevailed. Early intervention then introduced a new paradigm, approaching psychosis as a more dynamic phenomenon, for which recovery is possible, provided an appropriate approach is used. As this paradigm has not penetrated all fields of psychiatry, professionals starting in early intervention sometimes experience a real culture shock, the objective of this article being to map its contours in order to facilitate this transition. Methods Based on their knowledge of the literature and their clinical experience, the authors will highlight the aspects that distinguish early intervention practice from traditional practice with psychotic disorders. They adopt an experiential approach to these themes, addressing them not only in light of the scientific literature, but also and especially in the first person of the singular. Results The aspects identified and agreed upon by the three authors were grouped into seven themes: 1. the adoption of a recovery-oriented practice and the rejection of the pessimistic view of psychotic disorders, which refocuses practice on the person's life goals; this is accompanied by a different style of approach; 2. Transdisciplinarity and cross-fertilization of expertise with other team members, community organizations and families, which requires humility and openness; 3. Changes in the pharmacotherapeutic approach, characterized by increased attention to adverse effects (e.g., treatment-induced negative symptoms), the use of lower doses, and the proactive use of clozapine and long-acting injectable antipsychotics; 4. The need to tolerate some diagnostic uncertainty given the difficulties in making an accurate diagnosis, and the presence of complex co-morbidities that blur the picture; 5. The high stakes of the critical period, characterized by high stakes, such as the risk of suicide or social disinsertion, which put pressure on the clinician; 6. The importance of relays in the care trajectory, particularly between adolescent and adult psychiatry, and then between early intervention and other services; 7. The resistance to change that early intervention sometimes faces, as its importance is not always recognized, and its implementation can challenge existing services. Conclusion The differences between the traditional mode of practice with persons with a psychotic disorder and that of early intervention are numerous; while they represent challenges, they are also sources of considerable stimulation and satisfaction.

Crystal structures of the hexa-fluorido-phosphate salts of the isomeric 2-, 3- and 4-cyano-1-methyl-pyridinium cations and determination of solid-state inter-action energies.

The synthesis and crystal structures of the isomeric mol-ecular salts 2-, 3- and 4-cyano-1-methyl-pyridinium hexa-fluorido-phosphate, C7H7N2+·PF6-, are reported. In 2-cyano-1-methyl-pyridinium hexa-fluorido-phosphate, C-H⋯F hydrogen bonds form chains extending along the c-axis direction, which are associated through C-H⋯F hydrogen bonds and P-F⋯π(ring) inter-actions into stepped layers. For 3-cyano-1-methyl-pyridinium hexa-fluorido-phosphate, corrugated sheets parallel to [001] are generated by C-H⋯F hydrogen bonds and P-F⋯π(ring) inter-actions. The sheets are weakly associated by a weak inter-action of the cyano group with the six-membered ring of the cation. In 4-cyano-1-methyl-pyridinium hexa-fluorido-phosphate, C-H⋯F hydrogen bonds form a more open three-dimensional network in which stacks of cations and of anions are aligned with the b-axis direction. Dispersion-corrected density functional theory (DFT-D) calculations were carried out in order to elucidate some of the energetic aspects of the solid-state structures. The results indicate that the distribution of charge within a mol-ecular ionic cation can play a large role in determining the strength of a cation-anion inter-action within a crystal structure. Crystals of 2-cyano-1-methyl-pyridinium hexa-fluorido-phosphate are twinned by a 180° rotation about the c* axis. The anion in 3-cyano-1-methyl-pyridinium hexa-fluorido-phosphate is rotationally disordered by 38.2 (1)° in an 0.848 (3):0.152 (3) ratio.

How prevalent are anxiety disorders in schizophrenia? A meta-analysis and critical review on a significant association.

OBJECTIVE: The presence of anxiety disorders (AD) in schizophrenia (SZ) is attracting increasing interest. However, published studies have yielded very broad variations in prevalence rates across studies. The current meta-analysis sought to (1) investigate the prevalence of co-occurring AD in SZ by reporting pooled prevalence rates and (2) identify potential sources of variations in reported rates that could guide our efforts to identify and treat these co-occurring disorders in patients with SZ. METHODS: We performed a systematic search of studies reporting prevalence of AD in SZ and related psychotic disorders. Mean prevalence rates and 95% confidence intervals (CIs) were first computed for each disorder. We then examined the impact of potential moderators related to patient sampling or to AD assessment methods on these rates. RESULTS: Fifty-two eligible studies were identified. Pooled prevalence rates and CIs were 12.1% (7.0%-17.1%) for obsessive-compulsive disorders, 14.9% (8.1%-21.8%) for social phobia, 10.9% (2.9%-18.8%) for generalized AD, 9.8% (4.3%-15.4%) for panic disorders, and 12.4% (4.0%-20.8%) for post-traumatic stress disorders. For all disorders, we found significant heterogeneity in rates across studies. This heterogeneity could at least partially be explained by the effect of moderator variables related to patient characteristics or assessment methods. CONCLUSIONS: AD are highly prevalent in SZ, but important variations in rates are observed between studies. This meta-analysis highlights several factors that affect risk for, or detection of AD in SZ, and could, thus, have an important impact on treatment and outcome of SZ patients.

In vitro evaluation of Radachlorin sensitizer for photodynamic therapy.

This paper reports the evaluation of a new photosensitizer, Radachlorin in comparison with one of its well known components but used solely, Chlorin e(6). The photodynamic properties and cell uptake and localisation of the two drugs were compared. In vitro studies were conducted on human adenocarcinoma cells (HT29) and lung carcinoma cell line (A549). Both dyes showed an absorption maximum between 640 and 650 nm, but those absorption peaks are enhanced by interactions with serum, with a shifted maximum at 661 and 664 nm, and much higher absorbance. As Radachlorin is constituted of different products and as photoreactivity is dependent on absorbed light energy, we chose to adapt concentrations so that both drugs had the same absorption at the irradiation wavelength (664 nm) for photoreactivity tests, and express concentrations in optical density at 664 nm. The capacity of the two drugs to generate Reactive Oxygen Species was identical, but on HT29 cells, Radachlorin reaches its optimal LD50 sooner than Chlorin e(6). Radachlorin LD50 on HT29 cells was 0.0251 OD(664 nm) after 2 h and 0.0672 OD(664 nm) for Chlorin e(6) for a 20 J cm(-2) irradiation. Radachlorin gave very similar results on A549 cells, LD50 being 0.05 for 5 J irradiation, and 0.026 for 10 and 20 J cm(-2). Pharmacokinetics using fluorescence showed that, even if Radachlorin quickly crossed HT29 (a human colonic cancer line) cell membrane, cellular distribution evolved from a diffuse cytoplasmic repartition 1 hour after Radachlorin addition to a delimited localisation into organelles all around the nucleus. Radachlorin intracellular fluorescence decreased after 4 h, whereas we did not observe a decrease of Chlorin e(6) intracellular fluorescence for times up to 24 h. In both case, a quick decline was observed as soon as the culture medium was replaced with a drug-free one. Radachlorin appears to be an excellent photosensitizer, with similar phototoxicity to Chlorin e(6) on cell cultures, but with quicker kinetics, which could be an improvement if confirmed on further in vivo studies.

Secondary oxidants in human serum exposed to singlet oxygen: the influence of hemolysis.

Singlet oxygen (1O2) is produced by leucocytes during inflammatory reactions, various biochemical reactions and during photoreactions. It deactivates by reacting with a number of targets to produce reactive oxygen species (ROS) and peroxides (that in turn produce ROS). To verify whether serum had the same capability to deactivate secondary oxidants after exposure to 1O2, we provoked a photoreaction using rose bengal added to sera of 53 healthy donors and, after light delivery, reduced 2',7'-dichlorofluorescein (DCFH) was added at the end of irradiation and fluorescence of the oxidized derivative (DCF) was recorded. To avoid optical artifacts, we analyzed the influence of hemolysis. Deactivation capability of secondary oxidants after exposure to (1)O(2) was stable over a long period of time, slightly different between men and women, but standard biochemistry parameters had little influence. Hemolysis, age and platelet number reduced deactivation of 1O2-induced secondary oxidants. Addition of lysed cancer cells had no influence. Blood sampling in clot act tubes gave a better signal than in heparinized tubes. Red blood cells (RBCs) loaded with antioxidants strongly decreased deactivation of secondary oxidants. Assays are in progress to evaluate the clinical implications of these findings.

Photodynamic treatment of culture medium containing serum induces long-lasting toxicity in vitro.

Photodynamic therapy (PDT) produces singlet oxygen and reactive oxygen species (ROS) that damage tumor cells and the vasculature. The resulting effect is a balance between photo-oxidations through primary or secondary ROS and scavenging activity. Sensitizers are distributed in the extracellular space before and during cell sensitization, suggesting that PDT could act directly on cell structures and on extracellular compartments, including sera. In this study we endeavored to determine whether the application of PDT to culture medium could affect cell survival. Culture medium [RPMI 1640 supplemented with fetal calf serum (FCS)] was incubated with Rose Bengal and irradiated before being added to cells for various contact times as a replacement for untreated medium. Cells were then kept in darkness until the survival assay. Treated medium reduced cell survival by up to 40% after 30 min of contact for 10 microg/ml of Rose Bengal and 20 J/cm(2). Rose Bengal or m-THPC alone or irradiated in water had no effect. This effect was dependent on the doses of Rose Bengal and light and decreased when FCS was replaced by human serum mixed with FCS. The reduction in survival observed with treated medium was more pronounced when the cell doubling time was shorter. Analysis of ROS or peroxide production in treated medium by DCFH added at the end of irradiation of Rose Bengal in serum-containing medium revealed a long-lasting oxidizing activity. Our findings support the hypothesis of an ROS- or peroxide-mediated, PDT-induced, long-lasting cell toxicity.

In vitro and in vivo evaluation of Radachlorin(R) sensitizer for photodynamic therapy.

This paper reports the evaluation of a new photosensitizer, Radachlorin in comparison with one of its well known components but used solely, Chlorin e6. The photodynamic properties, cell uptake and localisation of the 2 drugs were compared. In vitro studies were conducted on human adenocarcinoma cells (HT-29) and lung carcinoma cell line (A549). Both dyes showed an absorption maximum between 640 and 650 nm, that were enhanced by serum, with a shifted maximum at 661 nm. In vitro, phototoxicities of Radachlorin and Chlorin e6 were nearly identical for HT29 and A549 cells. However, Radachlorin reached its optimal LD50 sooner (0.59 microg ml(-1) for 3 h incubation followed by 20 J cm(-2) of 664 nm light (0.02 W cm(-2))) than Chlorin e6 (0.60 microg ml(-1) for 4 h incubation). For in vivo studies, Swiss athymic mice were grafted with human lung carcinoma of the line A549 15 days before intravenous photosensitizer injection. Fluorescence was recorded through an optical fibre spectrofluorimeter using the 666 nm peak for detection. Maximum Radachlorin fluorescence in tumor was observed 2 h after injection (1412 +/- 313 AU). Selectivity was expressed by the calculated tumor-to-skin and tumor-to-muscle ratios. Maximum ratios (1.45 +/- 0.14 for tumor-to-skin and 1.95 +/- 0.29 tumor-to-muscle) were observed 7 h after injection with Radachlorin. Maximal Chlorin e6 fluorescence was observed 1 h (shortest time interval measured) after injection in all organs and highest tumor-to-muscle ratio (2.56 +/- 0.97) 8 h after injection. Chlorin e6 fluorescence in skin was always at least equivalent to tumor fluorescence. Complete response of grafted tumor was achieved (no recurrence observed during 15 days) after 20 mg kg(-1) IV injection and 200 J cm(-2) irradiation (0.3 W cm(-2)) with both drugs. Optimal delays between injection and light delivery were between 1 and 7 h with Radachlorin and 3 h for Chlorin e6 but severe adverse effects were noted for both drugs when drug-light intervals were shorter than 3 h. This suggests that clinical use would be easier with Radachlorin than Chlorin e6.

Photoreactivity of indirubin derivatives.

Twenty-nine analogs of indirubin, an isomer of indigo, have been synthesized to optimize its promising kinase inhibitory scaffold. These compounds being also pigmented, have been tested for their photoreactivity. Absorption maxima were between 485 nm and 560 nm. Addition of fetal calf serum induced fluorescence and time dependent absorption modifications. Appropriate illumination induced Reactive Oxygen Species (ROS) production for nineteen compounds out of twenty-nine. The relationship between fluorescence and ROS production is discussed. Six compounds showed an important toxicity on F98 cells, a murine glioma cell line. Three of these were found to be also phototoxic, as four other non-toxic compounds. All but one phototoxic compounds were detected as ROS producers by in vitro tests. Photoreactivity assessment is important to anticipate adverse reactions for compounds that might be clinically developed. The experimental assay was found to be the only way to evaluate the photoreactivity of this family of compounds since no predictive criteria on structures could be found. Combining the vascular tumor growth inhibition induced by kinase inhibitors with the massive local blood flow arrest following photodynamic treatment may be an efficient anti-cancer strategy. These data could orientate further syntheses of either non-photoreactive compounds or compounds displaying both kinase inhibitory activity and strong phototoxicity.

Photodynamic effects of SIM01, a new sensitizer, on experimental brain tumors in rats.

BACKGROUND: Glioblastomas are the third most common cause of cancer death in patients between 15 and 35 years old. Literature suggests that PDT could represent a promising treatment, providing that sensitizers could accumulate within the cancer tissues despite the blood-brain barrier. METHODS: Distribution and PDT effect of SIM01, a promising photosensitizer, have been evaluated on orthotopic C6 tumor model in rats by comparison with HPD and m-THPC. Pharmacokinetics had been analyzed with fluorescence and ROS. Photodynamic treatment was done using a 630-nm light with an energy density of 100 J cm(-2) for HPD and a 652-nm light with an energy density of 20 J cm(-2) for m-THPC and SIM01. RESULTS: The correlation between fluorescence and ROS dosimetry was found to be excellent. An optimal concentration was found after 12 hours for SIM01 (4 mg/kg), 24 hours for HPD (10 mg/kg), and 48 hours for m-THPC (4 mg/kg). The best normal tissue/cancer ratio of concentration had been found after 12 hours for SIM01 and 48 hours for HPD and m-THPC. Pathological examinations after PDT showed that the criteria for histology of glioblastic origin were absent in SIM01-treated rats 12 hours after injection but were present in 50% of rats treated 24 hours after injection and in all after a 48-hour delay. Mean survival of rats treated 12 or 24 hours after SIM01 injection was significantly improved compared with controls, HPD-, or m-THPC-treated groups. Survival of rats treated 12 or 24 hours after SIM01 injection reached 20 days but decreased for longer delays. On the contrary, survival reached 18 days at the maximum for rats treated 48 hours after m-THPC or HPD injection. CONCLUSIONS: Our results confirm that PDT is a promising treatment for glioblastomas. SIM01 efficacy is as efficient as m-THPC but with much more favorable pharmacokinetics.

Tobacco smoking within psychiatric inpatient settings: biopsychosocial perspective.

Tobacco smoking remains a neglected issue within general psychiatry despite high rates of associated morbidity and mortality. While there has been a coordinated community campaign to reduce tobacco smoking within the general population, mental health facilities have been reluctant to adopt such regulatory controls, and rarely target smoking prevention or treatment. This paper summarizes and discusses evidence relating to the clinical impact of tobacco smoking within inpatient psychiatric settings. A selective review of psychiatric and psychological research on smoking within inpatient settings was conducted, with a particular focus on the influence of smoking on the physical and mental health, pharmacotherapy, and social interactions of patients during their inpatient stay. Patients frequently alter their smoking habits during inpatient treatment, which can affect both their presentation and pharmacotherapeutic management. Smoking also appears to play a central role in social interactions on the ward, with staff frequently using cigarettes to reinforce certain behaviours. Despite current guidelines, mental health professionals rarely address nicotine use among their patients. Nevertheless, programmes that assist patients to quit during an inpatient stay have been shown to be both efficacious and cost-effective. Strategies that address staff concerns and assist in the implementation of effective smoking bans on psychiatric units are also available. Cessation should be a key component of inpatient treatment planning because this setting provides a safe and timely opportunity to help patients quit. A flowchart of interventions that could be incorporated within standard inpatient settings is proposed.

PDT in clinics: indications, results, and markets.

Photodynamic therapy (PDT) is based on the selective light activation of an exogenously given drug to patients. PDT acts mainly on cell membranes either of neovascular endothelial cells or of cancer cells leading to cancer cell death. Six drugs are now marketed based on clinical assays in various indications, which showed a clear cost efficiency as compared to other classical procedures. PDT is easy to handle and can be performed in medical installations fitting the conditions of health care in developing countries. Its cost effectiveness could represent an appropriate solution to the increasing number of cancers of various origin. However despite all the clinical results now available, PDT development remains slow. The reasons for this situation include cost of development, intellectual property, and competition between pharmaceutical companies.

The influence of storage conditions on delta amino levulinic acid induced toxicity and phototoxicity in vitro.

Delta amino levulinic acid photodynamic therapy (ALA-PDT) represents one of the most prominent advances in PDT. ALA itself or its derivatives are marketed for a variety of clinical indications. Despite the development of clinical applications, experimental ALA results are very heterogeneous and experimentally used parameters are still not standardized. This suggests that some problems remain unsolved that are likely to impair experiments to be performed but also that clinical results obtained could be greatly improved. Frequently unmentioned or imprecise data concern solvents, pH of ALA solutions, storage time, ALA degradation or ALA efficacy. In addition, diversity of experimental model is huge while capabilities of ALA transformation into PpIX are known to vary from one cell to the other. Thus, the aim of the present paper was to quantify the level of ALA degradation or changes in ALA efficacy using one single cell line without presuming of the mechanisms and determine the conditions of storage inducing the best transformation into PpIX and/or cell phototoxicity. We added ALA diluted in water, PBS or RPMI to C6 cells, a murine brain tumour cell line that can be used in vivo as an orthotopic graft. We measured in cells used as tools for final bio efficacy estimation, both the induced fluorescence and phototoxicity in various conditions of storage before use chosen to be as close as possible to the real lab conditions. Water had been found to better preserve ALA than, respectively, PBS and RPMI and this for any temperature or storage durations. The lowest temperature and the shortest duration for storage used had also been shown to better preserve ALA-induced fluorescence and phototoxicity. The fact that these properties were found to be better preserved in 7.4 buffered solvent could be in relationship with a fast ALA condensation occurring at neutral or lightly acidic pH modifying its availability for an optimal transformation into PpIX.

PDT for Barrett's esophagus: Status and unsolved problems.

PDT had been proposed in gastroenterology for various indications and the esophageal cancer treatment had been among the very first having been approved. However, PDT failed to be a real breakthrough. One reason for it was that although it had been approved for the palliative treatment of advanced tumors, PDT only has by nature a limited in-depth efficacy fitting better to the treatment and often the cure of "early cancers". For this reason PDT has also been proposed for the treatment of Barrett's esophagus (BE) with high-grade dysplasias. Barrett's mucosa (BM) is a field of a specialized metaplastic columnar epithelium replacing the normal stratified squamous epithelium or mucosa lining the distal esophagus. In this case, PDT has to destroy an area of thin tissues spread eventually over a wide area instead of a mass of tissues. Something important is that existing treatments allow the treatment of foci of dysplastic tissues but not the regression of the whole BM. BE is thus an unsolved medical problem having medical as well as economic consequences as BM being likely to transform into a cancer has to be carefully surveyed. The esophageal cancer, an adenocarcinoma, has to be surgically removed when it is possible something pretty heavy with a high morbidity. Economic burnt is also important with high survey costs independently to the additional surgical costs in case of diagnosed cancer. Treatments proposed for non or mild dysplastic BM regression have in common to have an inhomogenous impact on the target. Treatments for high-grade dysplasia (HGD, the ultimate pathological step before cancer) are based on mucosectomy and are limited to small areas of tissues. Recently circumferential mucosectomy had been proposed but at a higher risk making it suitable only to highly experienced hands in infrequent indications.

Variable phenotype related to a novel PAX 6 mutation (IVS4+5G>C) in a family presenting congenital nystagmus and foveal hypoplasia.

PURPOSE: Several ocular defects have been identified as a consequence of the PAX6 gene mutations. With regard to the implication of this gene in unusual phenotypes, we report a family presenting with congenital nystagmus, foveal hypoplasia, and iris hypoplasia or atypical coloboma. DESIGN: Observational case report. METHODS: The entire transcribed region of the PAX6 gene was submitted to mutation search at the DNA and mRNA levels in five affected members of a French family in test with 82 normal subjects. RESULTS: A novel heterozygous PAX6 gene splice mutation (IVS4 + 5G>C) was identified. The mutation is located in IVS4 within the consensus donor splice site. A mutant mRNA lacking exon 4 as the sole defect was evidenced. The resultant protein was predicted to contain a cryptic ATG initiation codon in exon 3 and a slightly altered paired-domain in an open reading frame extended by 13 amino acids. CONCLUSIONS: The association of anterior segment anomalies and foveal hypoplasia with one of the slightest alterations of the PAX6 protein described to date confirms the association of variant phenotypes with hypomorphic alleles. Mutation screening of the PAX6 gene could be useful in elucidating the origin of complex ocular malformations.

Screening for PAX6 gene mutations is consistent with haploinsufficiency as the main mechanism leading to various ocular defects.

PAX6, a paired box transcriptional factor, is considered as the master control gene for morphogenesis of the eye. Human PAX6 mutations have been associated with a range of eye abnormalities, including aniridia, various anterior segment defects and foveal hypoplasia. We carried out a mutational analysis of the PAX6 gene in 54 unrelated patients with aniridia or related syndromes. A deleterious variation was evidenced in 17 sporadic cases (50%) and in 13 (72%) familial cases. Twenty-four different mutations, 17 of which are novel, were found. The spectrum of PAX6 mutations was highly homogeneous: 23 mutations (96%) leading to premature stop codons (eight nonsense and four splice site mutations, 11 insertions and deletions) and only one (4%) missense mutation. Twenty-two mutations were associated with aniridia phenotypes whereas two were associated with atypical phenotypes. These latter encompassed a missense mutation (R19P) in an individual with a microphthalmia-sclerocornea and a splice site mutation (IVS4+5G > C) in a family presenting with a congenital nystagmus. Both represented the most probably hypomorphic alleles. Aniridia cases were associated with nonsense or frameshifting mutations. A careful examination of the phenotypes did not make it possible to recognise significant differences whenever the predicted protein was deprived of one or another of its functional domains. This strongly suggested that most of the truncating mutations generated null alleles by nonsense mediated mRNA decay. Our observations support the concept of dosage effects of the PAX6 mutations as well as presenting evidence for variable expressivity.