Prosopagnosia as the Presenting Symptom of Whipple Disease.

Whipple disease is a rare, chronic multisystem infectious disease. The central nervous system (CNS) is secondarily involved in 43% of patients; 5% of patients have isolated or primary CNS involvement. The most frequent CNS symptoms are cognitive changes. Prosopagnosia is an inability to recognize familiar faces, in a person who does not have vision impairments or cognitive alterations. This relatively rare condition is usually related to vascular, traumatic, degenerative, or infectious lesions. We report a 54-year-old woman who presented subacutely with fever, headache, and seizures that led to a diagnosis of infectious meningoencephalitis. She improved temporarily on broad-spectrum antibiotics, but then developed a chronically evolving cognitive impairment with associative prosopagnosia as the major complaint. She had a history of sporadic abdominal pain and mild sacroiliac arthralgia. After a negative duodenal biopsy, we confirmed primary CNS Whipple disease by polymerase chain reaction and brain biopsy. We treated the patient with ceftriaxone for 15 days and then co-trimoxazole for 2 years. At 8-year follow-up, she had no further impairments, but continuing prosopagnosia. To our knowledge, this is the first description of isolated prosopagnosia in a patient with primary CNS Whipple disease. Because CNS Whipple disease can lead to serious, irreversible lesions if not promptly treated, clinicians must suspect the diagnosis, treat with long-term antibiotics, and follow patients carefully to prevent recurrence.

Intranasal inhalation of oxytocin improves face processing in developmental prosopagnosia.

Developmental prosopagnosia (DP) is characterised by a severe lifelong impairment in face recognition. In recent years it has become clear that DP affects a substantial number of people, yet little work has attempted to improve face processing in these individuals. Intriguingly, recent evidence suggests that intranasal inhalation of the hormone oxytocin can improve face processing in unimpaired participants, and we investigated whether similar findings might be noted in DP. Ten adults with DP and 10 matched controls were tested using a randomized placebo-controlled double-blind within-subject experimental design (AB-BA). Each participant took part in two testing sessions separated by a 14-25 day interval. In each session, participants inhaled 24 IU of oxytocin or placebo spray, followed by a 45 min resting period to allow central oxytocin levels to plateau. Participants then completed two face processing tests: one assessing memory for a set of newly encoded faces, and one measuring the ability to match simultaneously presented faces according to identity. Participants completed the Multidimensional Mood Questionnaire (MMQ) at three points in each testing session to assess the possible mood-altering effects of oxytocin and to control for attention and wakefulness. Statistical comparisons revealed an improvement for DP but not control participants on both tests in the oxytocin condition, and analysis of scores on the MMQ indicated that the effect cannot be attributed to changes in mood, attention or wakefulness. This investigation provides the first evidence that oxytocin can improve face processing in DP, and the potential neural underpinnings of the findings are discussed alongside their implications for the treatment of face processing disorders.

Galactose uncovers face recognition and mental images in congenital prosopagnosia: the first case report.

A woman in her early 40s with congenital prosopagnosia and attention deficit hyperactivity disorder observed for the first time sudden and extensive improvement of her face recognition abilities, mental imagery, and sense of navigation after galactose intake. This effect of galactose on prosopagnosia has never been reported before. Even if this effect is restricted to a subform of congenital prosopagnosia, galactose might improve the condition of other prosopagnosics. Congenital prosopagnosia, the inability to recognize other people by their face, has extensive negative impact on everyday life. It has a high prevalence of about 2.5%. Monosaccharides are known to have a positive impact on cognitive performance. Here, we report the case of a prosopagnosic woman for whom the daily intake of 5 g of galactose resulted in a remarkable improvement of her lifelong face blindness, along with improved sense of orientation and more vivid mental imagery. All these improvements vanished after discontinuing galactose intake. The self-reported effects of galactose were wide-ranging and remarkably strong but could not be reproduced for 16 other prosopagnosics tested. Indications about heterogeneity within prosopagnosia have been reported; this could explain the difficulty to find similar effects in other prosopagnosics. Detailed analyses of the effects of galactose in prosopagnosia might give more insight into the effects of galactose on human cognition in general. Galactose is cheap and easy to obtain, therefore, a systematic test of its positive effects on other cases of congenital prosopagnosia may be warranted.

Cortical activation during cholinesterase-inhibitor treatment in Alzheimer disease: preliminary findings from a pharmaco-fMRI study.

OBJECTIVE: Cholinesterase inhibitors improve cognitive functioning in Alzheimer disease (AD). The authors studied, with functional magnetic resonance imaging (fMRI), the neural mechanism by which this cholinergic enhancement improves memory encoding in AD over longer time periods. METHODS: Brain activation was measured in 10 patients with AD and 10 healthy elderly comparison subjects with fMRI while they were encoding novel faces. Patients were scanned again after a 10-week open treatment with the cholinesterase-inhibitor donepezil. RESULTS: Neuropsychologically-tested memory performance improved during the treatment phase in the patients. During the encoding of novel faces, elderly comparison subjects showed more activation in the right fusiform gyrus than the group of AD patients. After a 10-week treatment with donepezil, the fusiform gyrus was also activated in patients, similar to the comparison group. CONCLUSIONS: The right fusiform gyrus is associated with the processing of faces. Cholinergic enhancement augments selective attention by increased selectivity of perceptual responses in patients with AD. This mechanism may contribute to a more efficient processing of the attended stimulus and thus be a mechanism underlying clinical improvement of cognitive functioning. These promising preliminary findings need to be confirmed in a larger, controlled trial in which both fMRI and attention measures serve as outcomes.