#3112 Acquired aphantasia in 88 cases: a preliminary report

Aims

For most of us, visual imagery is a fundamental feature of day-to-day subjective experience. It is thought to play multiple cognitive roles.1 However, there is widespread variation in the subjective intensity of visual imagery, ranging from extreme vividness to complete absence. The term aphantasia was coined recently to describe the latter, which is usually lifelong. While rarer, cases of acquired aphantasia can provide mechanistic insight. Isolated cases have long been reported,2 with some attempts at theoretical synthesis.3 4 We give a preliminary description of 88 such cases identified from among ~14,000 people contacting us in the wake of publicity surrounding Aphantasia.

Methods

Cases were selected from individuals contacting us spontaneously reporting reduced or absent intensity of visual imagery. Contacts were asked to complete two measures of visual imagery, the Vividness of Visual Imagery Questionnaire (VVIQ) and Imagery Questionnaire (IQ).5

Results

Cases were divided into those in with a strong probability of a neurological cause (n=39), a psychological cause (n=20) and those about which we cannot yet be confident (n=29). Functional aphantasia appears likely to account for some of the cases in the third category. The commonest precipitating events were head injury (n=19), affective disorder (n=17) and stroke (n=13). Other causes included surgery (postoperative) (n=7), drugs (n=6), infectious or inflammatory disease (n=3), neurodegenerative disease (n=3), and seizure disorders (n=2). For subjects completing the VVIQ (n=29), the mean score was 20.1/80 (range 16-32,) indicating marked reduction of imagery vividness. Localizable lesions were predominantly right sided (n=6) and occurred in posterior cortical areas, particularly occipital and parietal, as well as two cases associated with damage to temporal cortex. Some cases reported other impairments, including impaired memory (n=12), prosopagnosia (n=5) and navigational difficulties (n=2). Of cases who reported on their dreams (n=28), around half had lost visual dreaming, a third had preserved visual dreaming and the remainder had visual dreaming of reduced intensity.

Conclusions

To our knowledge, this is the largest reported case series of acquired loss of visual imagery. Both neurological and psychological disorders can be responsible for acquired aphantasia. Our series includes cases of probable functional aphantasia. Further detailed analysis of these cases is required.

References

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Do anti-tumour necrosis factor-α biologics affect subclinical measures of atherosclerosis and arteriosclerosis? A systematic review

AIMS

Inflammatory cytokines, particularly tumour necrosis factor-α (TNFα), are thought to promote arterial disease through a variety of mechanisms leading to arteriosclerosis and atherosclerosis. We reviewed the existing evidence of the effect of anti-TNFα treatment on arteriosclerosis and atherosclerosis in chronic inflammatory disease.

METHODS

We performed a systematic review of studies examining effects of monoclonal antibodies against TNFα on subclinical measures of arteriosclerosis (arterial pulse wave velocity) and atherosclerosis (endothelial function measured by flow-mediated dilation or forearm blood flow responses to endothelium-dependent agonists, and common carotid intima-media thickness).

RESULTS

We identified 60 studies (of 854 potential studies identified using a systematic search) in which effects of anti-TNFα biologics on these measures were assessed in patients receiving anti-TNFα therapy for a clinical indication (usually an inflammatory disease such as an inflammatory arthritis, psoriasis or inflammatory bowel disease). Of these, only 6 were randomised clinical controlled trials. Whilst many observational studies and noncontrolled studies reported positive findings, positive finding were reported in only 1 of 6 randomised clinical controlled trials.

CONCLUSIONS

There is no strong evidence for an effect of anti-TNFα biologics on the subclinical measures of arteriosclerosis or atherosclerosis examined in this review. This does not exclude a positive effect of TNFα biologics on clinical outcomes through alternate pathways including those induced by remission of the primary inflammatory disease.

Outcomes in coeliac disease: a qualitative exploration of patients' views on what they want to achieve when seeing a dietitian

BACKGROUND

Coeliac disease (CD) is managed by life-long adherence to a gluten-free diet and dietitians have the potential to facilitate this. Patient involvement through shared decision-making is central to behaviour-change skills used by dietitians, although there is little evidence supporting its inclusion in evaluating dietetic interventions. The present study aimed to explore patients' preferences for diet and nutrition-related outcomes in CD.

METHODS

Adults with CD or adult carers of children with CD were invited through support networks. Participants took part in a telephone, face-to-face interview or focus group which was audio-recorded and transcribed. Themes were developed using a framework method. Ethical approval was obtained.

RESULTS

Twenty-nine adult patients and five parents of CD children participated 0-34 years after diagnosis. Four main outcome-related themes emerged: (i) Participants wanted information specific to their lifestyle and time since diagnosis, focussing on food containing gluten, practical issues, prescribable items and general nutrition. (ii) The degree of satisfaction with the consultation process impacted on participants' experience, including the dietitian's CD expertise, consistency of the dietitian seen, and the frequency and length of appointments. (iii) Health concerns were important to participants and focussed on risk of osteoporosis, unwanted weight gain, and the fat and sugar content of manufactured gluten-free products. (iv) Clinical monitoring, including bone scans and antibody measurements, was mentioned but was not described as being of importance for most participants.

CONCLUSIONS

The outcomes preferred by CD patients and carers focussed primarily on information and resources received and satisfaction with their dietetic consultation.

Treatment with Mefolinate (5-Methyltetrahydrofolate), but Not Folic Acid or Folinic Acid, Leads to Measurable 5-Methyltetrahydrofolate in Cerebrospinal Fluid in Methylenetetrahydrofolate Reductase Deficiency

S-adenosyl methionine, which is formed from methionine, is an essential methyl donor within the central nervous system. Methionine is formed by the enzyme methionine synthase for which 5-methyltetrahydrofolate (5-MTHF) and homocysteine are substrates. Patients with severe methylenetetrahydrofolate reductase (MTHFR) deficiency cannot make 5-MTHF and have extremely low levels in the CSF. As a consequence, methylation reactions in the CNS are compromised, and this is likely to play an important role in the neurological abnormalities that occur in MTHFR deficiency. Although treatment with oral betaine can remethylate homocysteine to methionine in the liver, betaine crosses the blood-brain barrier poorly, and CSF levels of methionine remain low. We report three patients with severe MTHFR deficiency (enzyme activity ≤1% of controls) who had undetectable levels of CSF 5-MTHF at diagnosis and while on treatment with either folic acid or calcium folinate. Only treatment with oral 5-MTHF given as calcium mefolinate at doses of 15-60 mg/kg/day resulted in an increase in CSF 5-MTHF.

Assessment of nurse-led screening of pigmented lesions using SIAscope

The incidence of malignant melanoma in the UK is rising. Increased awareness of melanoma has led to an increase in patients presenting with pigmented lesions to their general practitioner (GP) and to pigmented lesion clinics. The sensitivity and specificity of the general practitioner in diagnosing melanoma remains poor.

OBJECTIVES

A trial was conducted to establish the effectiveness of SIAscope in triaging patients referred by GPs on suspicion of melanoma.

MATERIALS AND METHODS

After Ethical Committee approval, all consenting patients attending the Pigmented Lesion Clinic at Frenchay Hospital were scanned with the SIAscope. The consultant then examined all the patients and all suspicious lesions were excised and examined.

RESULTS

Eight hundred and eighty-six patients were included in the trial. The SIAscope had a sensitivity of 94.4% with a false negative rate of 3.7% for malignant melanoma.

CONCLUSIONS

The SIAscope could be useful in reducing the number of benign lesions seen by the consultant while still identifying most melanomas.

Activation of extracellular signal-regulated protein kinase 5 downregulates FasL upon osmotic stress

Extracellular signal-regulated protein kinase (ERK) 5 is a mitogen-activated protein kinase (MAPK) that is activated by dual phosphorylation via a unique MAPK/ERK kinase 5, MEK5. The physiological importance of this signaling cascade is underscored by the early embryonic death caused by the targeted deletion of the erk5 or the mek5 genes in mice. Here, we have found that ERK5 is required for mediating the survival of fibroblasts under basal conditions and in response to sorbitol treatment. Increased Fas ligand (FasL) expression acts as a positive feedback loop to enhance apoptosis of ERK5- or MEK5-deficient cells under conditions of osmotic stress. Compared to wild-type cells, erk5-/- and mek5-/- fibroblasts treated with sorbitol display a reduced protein kinase B (PKB) activity associated with increased Forkhead box O3a (Foxo3a) activity. Based on these results, we conclude that the ERK5 signaling pathway promotes cell survival by downregulating FasL expression via a mechanism that implicates PKB-dependent inhibition of Foxo3a downstream of phosphoinositide 3 kinase.

Incorporating a social networking approach to enhance contact tracing in a heterosexual outbreak of syphilis

OBJECTIVE

This report describes the outcomes of a social networking approach (SNA) in a heterosexually transmitted syphilis epidemic by street nurses in British Columbia, Canada.

METHODS

Street nurses used SNA interviewing cues, environmental observation, peer outreach, serial interviewing, conducted blood tests, and offered treatment on the street. Rates of cases of syphilis identified by outreach nurses and cases linked to another case were compared before and after adoption of an SNA.

RESULTS

SNA resulted in a significantly increased proportion of cases identified by the street nurses (p = 0.01) and increased the percentage of cases linked to a previous case (p = 0.03).

CONCLUSION

This preliminary study confirms that SNA can increase the number of cases and contacts identified in an epidemic of a sexually transmitted disease in a vulnerable, hard to reach population.

Law and policy in the era of reproductive genetics

The extent to which society utilises the law to enforce its moral judgments remains a dominant issue in this era of embryonic stem cell research, preimplantation genetic diagnosis, and human reproductive cloning. Balancing the potential health benefits and diverse moral values of society can be a tremendous challenge. In this context, governments often adopt legislative bans and prohibitions and rely on the inflexible and often inappropriate tool of criminal law. Legal prohibitions in the field of reproductive genetics are not likely to reflect adequately the depth and diversity of competing stakeholder positions. Rather, a comprehensive and readily responsive regulatory policy is required. Such a policy must attend to the evolving scientific developments and ethical considerations. We outline a proposal for effective, responsive, and coherent oversight of new reproductive genetic technologies.

Ovarian stimulation of marmoset monkeys (Callithrix jacchus) using recombinant human follicle stimulating hormone

To reduce the number of animals required for controlled studies of marmoset oocytes and early embryos, a superovulation protocol was developed for the common marmoset. Females were given up to 50 i.u./day recombinant human follicle stimulating hormone (FSH)--(r-hFSH) for 6 days. Ovaries were visualized by a modified laparoscopic technique and follicular aspiration was performed using a needle and suction apparatus inserted directly through an otoscope speculum. The number of follicles + ovulation points (+/- S.E.) was 2.9 (+/- 0.2) in controls and 14.1 (+/- 1.6; P < or = 0.001) in the 50 i.u. r-hFSH per day animals. Oocytes, typically at the germinal vesicle stage at collection, extruded a first polar body within 26 hours. In vitro fertilization was performed and embryos developed to the hatched blastocyst stage (34%). With many high quality oocytes and the ability to synchronize cycles, the marmoset is a valuable primate model for examining nuclear reprograming and early embryonic events.

Pregnancy and live birth from nonsurgical transfer of in vivo- and in vitro-produced blastocysts in the rhesus monkey

Embryo transfer in the rhesus monkey has been historically limited to transfer of cleavage stage embryos. In order to allow genetic manipulation of rhesus embryos in vitro, without using invasive surgical techniques, it is important to explore the transfer of morula and blastocyst stage embryos. Embryos were produced by in vitro fertilization from gonadotropin-stimulated monkeys, or were obtained by nonsurgical uterine flushing of naturally mated or artificially inseminated females. Nonsurgical transfer was accomplished by inserting a metal guide through the cervix into the uterus, after which a hollow cell sampler was inserted over the guide. The guide was removed and a catheter was inserted containing one to five embryos. Several pregnancies resulted from in vitro- and in vivo-derived blastocysts, and two pregnancies were carried to term resulting in one live birth. Blood samples were collected regularly to monitor plasma levels of chorionic gonadotropin, luteinizing hormone, and progesterone. The recipients received progesterone as a subcutaneous implant or daily injections from the day of transfer. The approach described in this study provides the opportunity to explore transgenic and chimeric models in the monkey by the development of noninvasive methods to transfer late-stage embryos that have been manipulated in vitro.

A population-based survey of tuberculosis symptoms: how atypical are atypical presentations?

There is scant information on tuberculosis symptoms from a population-based perspective. We prospectively identified 526 tuberculosis cases reported in Los Angeles County over a 6-month period. Of 313 persons who completed our questionnaire, 72.7% had cough, 48.2% for >2 weeks, and 52.3% had fever, 29.4% for >2 weeks. Among those with pulmonary disease, only 52.4% had cough for >2 weeks. In a multivariate model, persons with significant symptoms typical of tuberculosis disease (defined as cough or fever for >2 weeks, weight loss, or hemoptysis) were associated with lack of medical insurance, negative tuberculin skin test, diagnosis during a process other than screening, and non-Asian race. In summary, classic symptoms of prolonged cough and fever are insensitive predictors of tuberculosis. Our data suggest that Asians may need to be added to the list of persons who present with tuberculosis atypically. We believe that the Infectious Diseases Society of America guidelines for community-acquired pneumonia should emphasize demographic features in addition to clinical symptoms when suggesting which patients require evaluation for Mycobacterium tuberculosis.

Foci of tuberculosis transmission in central Los Angeles

To identify sites of tuberculosis transmission and to determine the contribution of HIV-infected patients to tuberculosis morbidity in an urban area, we prospectively evaluated 249 patients with culture-proven tuberculosis in central Los Angeles. Restriction fragment length polymorphism (RFLP) analysis was performed on Mycobacterium tuberculosis isolates to identify patients infected with the same strain. Using RFLP and clinical and epidemiologic data, we identified the most likely source case and site of transmission for 79 patients. Homelessness, birth in the United States and Native American ethnicity were independent predictors of being a source case, but HIV infection was not. Three homeless shelters were sites of tuberculosis transmission for 55 (70%) of the 79 patients. HIV-infected patients constituted 27% (66/249) of the study population, but only 17% (13/79) of patients were infected by an HIV-infected source case. We conclude that transmission of tuberculosis in central Los Angeles was highly focal, and that the major transmission sites were three homeless shelters. HIV- infected tuberculosis patients did not play a major role in spread of tuberculosis. Tuberculosis control measures targeted at specific homeless shelters can reduce tuberculosis morbidity in urban areas where homelessness is common and the incidence of tuberculosis is high.

Tuberculosis in homeless patients: potential for case finding in public emergency departments

STUDY OBJECTIVES

Previous studies have had difficulty evaluating the optimal clinical site for screening homeless patients for active tuberculosis (TB). We hypothesized that homeless patients with TB would not frequently reside in shelters at the time of their diagnosis and would be more likely than other patients with TB to seek care in public hospitals, thus presenting an opportunity for screening radiography.

METHODS

This registry-based survey included 743 consecutive patients with confirmed active TB in Los Angeles County. No therapeutic intervention was involved.

RESULTS

When compared with patients with TB who were not homeless, homeless patients with TB were more likely to be male (93% versus 63%, P<.001), black (44% versus 15%, P<.001), living in the inner city (55% versus 7%, P<.001), and born in the United States (67% versus 32%, P<.001). They were more infectious than other patients with TB as evidenced by a trend toward more cavitary radiographic lesions (24% versus 16%, P=.11) and significantly more positive sputum smears (56% versus 41%, P=.009). Less than a third lived in congregate facilities such as shelters at the time of their diagnosis. Instead, their disease was diagnosed more often at county hospitals (54% versus 23%, P<.001) than patients with TB who were not homeless.

CONCLUSION

Widespread screening for TB in shelters may miss most homeless patients with TB. Because most county-hospital homeless patients with TB initially present to emergency departments and many do not live in shelters, future cost-effectiveness studies should evaluate chest radiograph screening for all homeless ED patients.

Relationship of isoniazid resistance to human immunodeficiency virus infection in patients with tuberculosis

To investigate the relationship between isoniazid resistance and HIV infection in patients with tuberculosis, we evaluated data in the Los Angeles County tuberculosis registry on 1,506 patients for whom drug susceptibility results were available. Among 235 HIV-infected patients, isoniazid resistance was less common than in 1,271 patients who were HIV-seronegative or who had not been tested for HIV, with an unadjusted odds ratio of 0.3. After adjustment for other factors that affect drug resistance (ethnicity, country of birth, prior diagnosis of tuberculosis, and cavitation), the frequency if isoniazid resistance remained lower than that in patients without HIV infection, with an odds ratio of 0.4 (95% confidence interval, 0.2 to 0.8; p = 0.02). We conclude that in Los Angeles, a setting where there is no ongoing outbreak of drug-resistant tuberculosis, isoniazid-resistant tuberculosis is not more common in HIV-infected patients.

Processes underlying young children's spatial orientation during movement

Children between 1.5 and 4 years old were tested for their ability to relocate a hidden object after a 180 degrees self-produced movement around an array of four locations. In one task the object's location relative to the other locations could be uniquely defined within one dimension, while in another two dimensions were needed to do this. No differences emerged between conditions, and by 3 years few errors occurred, despite the fact that children were unable to view the array during movement. This indicates either that young children encounter no specific difficulty in coordinating dimensions or that they solved the task without recourse to such a system. An error analysis supports the second possibility. Children apparently tackled the task by a system directly related to body movement, since errors were frequently the result of incomplete compensation for movement around the array. In a second study in which the four containers were placed in contact, children's performance declined and the relation between direction of movement and error was replaced by some evidence for updating on the near-far dimension accompanied by failure to update the left-right dimension. Thus children appear to change strategy when the problem requires more precise specification of target location.

Unsatisfactory performance of the leukocyte esterase test of first voided urine for rapid diagnosis of urethritis

BACKGROUND AND OBJECTIVES

The objective of this study was to determine the performance characteristics of a dipstick test for leukocyte esterase (LE), (Chemstrip 2LN, Boehringer Mannheim) in predicting the presence of urethritis and urethral pathogens in men presenting to a busy sexually transmitted disease clinic and to street outreach facilities.

METHODS

Urethral swabs for polymorphonuclear (pmn) cell count, gonorrhoea culture and chlamydia enzyme immunoassay (EIA) as well as 15 ml of first voided urine (FVU) were collected from 737 symptomatic and 726 asymptomatic men. Gonorrhoea cultures and pmn counts were processed according to standard methods. Either Abbott Chlamydiazyme EIA (confirmed) or Syva Microtrak EIA (confirmed) test was employed to detect C trachomatis. The LE test was immediately dipped in FVU, read after 60-120 seconds by the clinician and considered positive if trace, 1+ or 2+.

RESULTS

Microscopic evidence of urethritis (> or = = 4 pmn cells per 1000 x field) was found on urethral smear of 782 (53.5%) patients. Chlamydia, gonorrhoea or both were present in 104 (7.1%) patients. Performance characteristics of the LE test were as follows: (table below)

CONCLUSION

The LE test did not have adequate sensitivity to be considered a reliable rapid diagnostic test for urethritis or urethral pathogens, particularly in the asymptomatic portion of this STD clinic population.

Faecal incontinence due to perianal cellulitis

A 4-year-old boy presented with a 6-week history of painful defaecation and faecal incontinence due to streptococcal perianal cellulitis. After treatment with a 10-day course of oral penicillin his symptoms had fully resolved. Early diagnosis and treatment of this under-recognised condition is essential.

Electromyographic study of the rigidospasticity of athetosis

The static and dynamic components of the tonic stretch reflex and shortening reactions have been studied in 10 patients with athetosis. EMG activity could be recorded only from the biceps muscle when the patient was at rest. The dynamic stretch reflex increased with the velocity of stretching in all muscles examined except the biceps. The biceps stretch reflex was found to be inhibited by increasing muscle length, whereas the stretch reflexes of triceps, hamstrings, and quadriceps muscles were facilitated by increasing muscle length. Reinforcement increased resting activity in the biceps and the dynamic shortening reaction of the triceps muscle. Both these effects were suppressed by the action of phenoxybenzamine. Although phenoxybenzamine was shown to reduce muscle tone in a double-blind controlled trial, no corresponding improvement was detected in involuntary movements or the patients' performance in a tracking test. The differences between the pattern of hypertonus in athetosis, Parkinson's disease, spasticity, and activated normal subjects are presented in discussion.