Polycystic lipomembranous osteodysplasia with sclerosing leukoencephalopathy should be considered in adult patients under age 50 years with dementia and basal ganglia calcification. Radiographs of ankles and wrists, and DNA test in uncertain cases, confirm the diagnosis.

Niemann-Pick disease type C (NP-C) is a rare, progressive, irreversible disease leading to disabling neurological manifestations and premature death. The estimated disease incidence is 1:120,000 live births, but this likely represents an underestimate, as the disease may be under-diagnosed due to its highly heterogeneous presentation. NP-C is characterised by visceral, neurological and psychiatric manifestations that are not specific to the disease and that can be found in other conditions. The aim of this review is to provide non-specialists with an expert-based, detailed description of NP-C signs and symptoms, including how they present in patients and how they can be assessed. Early disease detection should rely on seeking a combination of signs and symptoms, rather than isolated findings. Examples of combinations which are strongly suggestive of NP-C include: splenomegaly and vertical supranuclear gaze palsy (VSGP); splenomegaly and clumsiness; splenomegaly and schizophrenia-like psychosis; psychotic symptoms and cognitive decline; and ataxia with dystonia, dysarthria/dysphagia and cognitive decline. VSGP is a hallmark of NP-C and becomes highly specific of the disease when it occurs in combination with other manifestations (e.g. splenomegaly, ataxia). In young infants (<2 years), abnormal saccades may first manifest as slowing and shortening of upward saccades, long before gaze palsy onset. While visceral manifestations tend to predominate during the perinatal and infantile period (2 months–6 years of age), neurological and psychiatric involvement is more prominent during the juvenile/adult period (>6 years of age). Psychosis in NP-C is atypical and variably responsive to treatment. Progressive cognitive decline, which always occurs in patients with NP-C, manifests as memory and executive impairment in juvenile/adult patients. Disease prognosis mainly correlates with the age at onset of the neurological signs, with early-onset forms progressing faster. Therefore, a detailed and descriptive picture of NP-C signs and symptoms may help improve disease detection and early diagnosis, so that therapy with miglustat (Zavesca®), the only available treatment approved to date, can be started as soon as neurological symptoms appear, in order to slow disease progression.

Niemann-Pick type C disease is a fatal neurovisceral disorder linked to dysregulation in cholesterol processing. A medication for this disease is currently being tested in clinical trials. However, there is a lack of information on neuropsychological testing parameters for this disease. One aim of this pilot study was to evaluate a test battery that could be used to assess cognitive deficits in different stages of the disease. A second aim was to determine whether specific functional deficits are associated with certain disease stages. Eight men and two women (19-40 years of age) harbouring mutations in the gene coding for the cholesterol trafficking protein NPC1 were put through the same test battery independently of their disease stage. The external staging criterion was based on a five-step clinical scale. Trail Making tests A & B and verbal fluency were sensitive indicators at early stages of NPC. Corsi Block-Tapping, Mini Mental Status, Find Similarities and Clock Drawing showed abnormal results in patients with advanced disease. The Grooved Pegboard, Trail Making and Mosaic tests were unsuitable in advanced disease due to impaired fine motor skills. We observed that visuospatial working memory was less affected by the neurodegenerative process than verbal working memory. The series of tests used here could be supplemented by the severe impairment battery and Raven matrices tests for patients with advanced disease.

The present study evaluated the effects of once-daily memantine (20 mg) treatment on cognition and communication in patients with moderate to severe Alzheimer's disease (AD). In a multicenter, single-arm open-label study, outpatients diagnosed with AD (MMSE < 20; n = 97) were titrated from 5 mg to 20 mg once-daily memantine over 4 weeks. Once-daily memantine treatment (20 mg) was then continued for 8 weeks, followed by a 4-week wash-out period. The primary efficacy endpoint was the change from baseline in the Consortium to Establish a Registry for Alzheimer's Disease -Neuropsychological Battery (CERAD-NP) total score. Secondary efficacy endpoints included change from baseline in Functional Communication Language Inventory (FLCI) and ADCS-ADL19 total score, and the response from baseline in Clinical Global Impression of Change (CGI-C). The CERAD-NP total score improved significantly after 12 weeks of once-daily memantine treatment compared with baseline (5.9 ± 8.8; p < 0.0001). The FLCI total score improved significantly after 12 weeks compared with baseline (4.4 ± 6.8; p < 0.0001). These significant improvements were already observed after 4 and 8 weeks of once-daily memantine treatment and persisted after a 4-week wash-out period. ADCS-ADL19 total scores showed only slight increases from baseline, and CGI-C indicated that the majority of patients experienced an improvement or stabilization of the disease after 12 weeks. At least one Treatment-Emergent Adverse Event was reported by 38 (39.2%) patients. In patients with moderate to severe AD, once-daily memantine (20 mg) treatment significantly improved cognition and functional communication and was found to have a favorable safety and tolerability profile.

NPC should be considered as a possible cause of psychiatric manifestations in patients with an atypical disease course, acute-onset psychosis, treatment failure, and/or certain combinations of psychiatric/neurological/visceral symptoms.

Several clinical niches have been identified that harbor patients at increased risk of NP-C.

Organic causes of psychoses may have an unrecognised yet notable prevalence, particularly in adolescent or adult patients. Several inherited metabolic disorders can present with psychiatric signs. In some disorders, such as Niemann-Pick type C (NP-C), the disease may remain unrecognised for many years due to a heterogeneous and subtle clinical presentation. In patients presenting with psychoses, subtle signs such as vertical supranuclear gaze palsy, ataxia and splenomegaly should raise the suspicion of NP-C. Miglustat is so far the only approved treatment for NP-C. Miglustat can stabilise neurological disease, particularly in adolescent or adult-onset patients who are detected as early as possible, before irreversible neurological damage occurs.

To examine the relationship between apolipoprotein E ε4 (ApoE ε4) and psychiatric symptoms, we compared ε4/ε4, ε3/ε3, and ε3/ε4 subjects. 659 outpatients with memory complaints underwent comprehensive neuropsychiatric assessment interview and neurological examination and ApoE genotyping: 98 were ε4/ε4. 18.4% (n = 18) ε4/ε4, 19.3% (n = 45) ε3/ε4, and 5.4% (n = 14) ε3/ε3 presented with symptoms of anxiety (p = 0.00001). ε4/ε4 patients with mild cognitive impairment (MCI; p < 0.0001) and those with Alzheimer's disease with late onset (p = 0.0175) were the most frequently affected. For anxiety, there were no gender dependent differences in the two homozygous groups, however, in the ε3/ε4 group, anxiety symptoms were evident in 7.3% (n = 8) of the male versus 30.1% (n = 37) of the female ε3/ε4 heterozygotes (p < 0.0001). Depression was found in 20.4% (n = 20) ε4/ε4 and 21.0% (n = 49) ε3/ε4 compared to 17.1% (n = 44) ε3/ε3 (p = 0.5181). Visual hallucinations were reported in 5.1% (n = 5) ε4/ε4 as opposed to 3.8% (n = 9) ε3/ε4 and 2.3% (n = 6) ε3/ε3 (p = 0.5278). We have seen a higher association of anxiety with the ApoE ε4 allele across all stages of disease and what may be a dosing effect in the early stage (MCI) for this ostensible risk, since we see a significantly higher frequency in the ApoE ε4 homozygotes when compared to the heterozygotes.